Cardiac troponin t quantification

Abstract

The present invention refers, inter alia, to a method of determining the amount of cardiac Troponin T (cTnT) in a sample, said method comprising a) contacting the sample with an anti-cTnT antibody and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT, wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT, thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT; as well as to uses of said antibodies for determining the amount of cTnT, for preventing skTnT interference in determining the amount of cTnT, and / or for maintaining and / or improving specificity and diagnostic accuracy for a disease associated with cTnT.

Description

Applicant: Roche Diagnostics GmbH Our Ref.: ROC17886PCT Date: 20.12.2024 Cardiac Troponin T quantification

[0001] The present application claims priority of the European Patent application No. 23219579.2, filed December 22, 2023, the disclosure of which is incorporated herein by reference in its entirety. FIELD OF THE INVENTION

[0002] The present invention relates to a method of determining the amount of cardiac Troponin T (cTnT) in a sample, said method comprising the steps of a) contacting the sample with an antibody against cTnT (anti-cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT. The present invention also relates to a composition and a composite composition, comprising said antibodies, and their use in diagnosing a disease associated with cTnT, as well as uses of said antibodies and said (composite) composition for determining the amount of cTnT in a sample, for preventing skTnT interference in determining the amount of cTnT in a sample, for maintaining or improving specificity in determining the amount of cTnT in a sample, and / or for maintaining or improving diagnostic accuracy and / or diagnostic specificity for a disease associated with cTnT, respectively. BACKGROUND OF THE INVENTION

[0003] Troponins are regulatory protein complexes that are involved in the contraction mechanism of striated muscle by forming complexes with tropomyosin and actin. Troponins are built of three monomeric subunits, namely troponin I (TnI), troponin C (TnC), and troponin T (TnT). TnT has a comparable high binding affinity to both tropomyosin, TnI and TnC, which can bind calcium ions in addition to the other two troponin monomers TnI and TnT. When calcium ions are released from the sarcoplasmic reticulum, said ions can bind TnC, which leads to a conformational change of TnI. This results in an exposure of myosin binding sites on the actin filaments previously blocked by tropomyosin, while binding of myosin heads to actin is nowpossible. Thus, in the presence of calcium ions, tropomyosin, which obscures the myosin-binding site on actin, is displaced via conformational change and displacement of the troponin complex on the actin filament, thereby triggering muscle contraction. Thus, troponins are integral to the contraction of muscles with TnT anchoring the troponin complex onto the actin filament and transducing calcium-dependent conformational changes induced by binding of calcium to TnC and conformational change of TnI to configure the actin filament and regulate muscle contraction and relaxation.

[0004] In case of the troponin subunits TnI and TnT different isoforms exist in humans, which can show, e.g., tissue-specific expression. Accordingly, TnI and TnT isoforms with cardiac or skeletal muscle restricted expression may also referred to as skeletal TnI and cardiac TnI as well as skeletal TnT (skTnT) and cardiac TnT (cTnT), respectively. Furthermore, TnI and TnT isoforms can be distinguished based on the muscle type, wherein the respective isoform is expressed. Muscles like skeletal muscles comprise slow-twitch and / or fast-twitch muscle fibers and may also be referred to as slow-twitch or fast-twitch muscles depending on their respective predominant fiber type. While for example human skeletal muscles in the back or the back of the lower legs are primarily built of slow-twitch fibers, fast-twitch muscle fibers can be found for example as primary fiber type in smaller muscles in hands and around eyes enabling rapid movements. Fast- twitch muscle fibers can also be found in skeletal muscles as these fibers have the ability to contract quickly and thus, enable high-intensity activities for short periods, like sprinting and jumping. In case of TnT, vertebrates exhibit three genes that encode for fiber-type-specific TnT genes with TNNT1 encoding slow skeletal muscle TnT (sskTnT), TNNT2 encoding cTnT, and TNNT3 encoding fast skeletal muscle TnT (fskTnT). Moreover, alternative splicing adds further complexity to the biological function of troponins.

[0005] Troponins can offer valuable insights into biological processes and deviations thereof. For example, cardiac troponin T is released into the blood upon heart muscle damage, necrosis and / or degeneration. Thus, cTnT release into the blood is considered indicative for cardiac diseases such as, e.g., myocarditis, acute coronary syndrome and acute myocardial infarction (AMI). Especially cardiac troponins represent important biomarkers, e.g., for the diagnosis of AMI due to their specificity for myocardial cell necrosis and a superior sensitivity than creatine kinase muscle brain (CKMB), which has been used as indicator of AMI before the development of cardiac troponin assays. Furthermore, elevated cardiac troponin concentrations may also be observed, e.g., in cases of non-ischemic cardiac diseases. Accordingly, serum levels of cTnT are commonly considered as important biomarkers, e.g., for detection, (differential) diagnosis and / or prognosis of heart diseases, for predicting pre-operatively a perioperative risk of major adverse cardiac events in the context of non-cardiac surgeries as well as in diagnosis of perioperative myocardial infarction and myocardial injuries after non-cardiac surgeries.

[0006] While cTnT and cTnI have been considered cardiac specific and equivalent in the diagnosis, e.g. of AMI, there has been some debate in view of reports about elevated cTnT levels in the absence of elevated cTnI levels in some patients. For example, Lavallaz et al (Circulation, 2022, 145:1764–1779, DOI: 10.1161 / CIRCULATIONAHA.121.058489) disclosed discrepancies between cTnT and cTnI levels in a subset of patients without cardiac disease, though with active non-inflammatory myopathy and myositis. It was concluded that there might have been a confounding effect that may affect exclusively cTnT, though not cTnI, measurements, and that clinical implications of a cTnT level based AMI diagnosis for patients presenting with a skeletal muscle disorder (SMD) remain to be elucidated. Four main hypotheses have been discussed in view of such reports and the challenge of potentially false positive diagnostic results based on elevated cTnT measurements. For example, two hypotheses assume that a respective cTnT assay could exhibit a high prognostic value for true positive results as SMD patients often have concomitant cardiac involvement and / or present with a structural heart disease unrelated to SMD. Another hypothesis assumes a potential re-expression of some isoforms of cTnT in skeletal muscle. Even another hypothesis assumes that there may be a potential cross-reactivity of skTnT with commercially available cTnT quantification assays. However, concerning the latter hypothesis, it may exemplarily be referred to the Elecsys® cTnT-hs assay, for which it is stated in the method sheet that there has been no significant cross-reaction observed with skTnT (0.003%), cTnI (0.2%), skTnI (0.003%) or TnC (<0.001%), when tested with cTnT concentrations of ~18 ng / L and ~38 ng / L and cross-reacting substance concentrations of 500 ng / mL.

[0007] Nevertheless, some uncertainty may have remained in view of a potential cross- reactivity of skTnT with commercially available cTnT quantification assays, especially in the context of point of care applications. Point of care situations may not allow assessing a patient´s health and / or fitness status comprehensively before diagnosis and treatment initiation. However, in the absence of a comprehensive fitness and / or health status information, not only a potentially undiagnosed SMD may represent challenges. SMD relates to a poorly defined, heterogeneous group of comparably rare disorders affecting skeletal musculature. For example, while coronary artery disease may affect more than 1,500 subjects out of 100,000, less than 100 subjects are affected by SMD. However, elevated serum concentrations of skeletal troponins may not only be caused by SMD, but have also been reported in case of skTnI, e.g., after statin treatment, maximal eccentric contractions and after marathons (cf. e.g. Chapman et al., Science and Medicine in Sport 2013; Trentini et al., BiochemMed (Zagreb), 2019.; Paana et al., International Journaly of Cardiology, 2019). Hence, there is still a need to have at hand alternative solutions for being able to reliably quantify cTnT, e.g., for point of care situations.SUMMARY OF THE INVENTION

[0008] The present invention addresses the need for precise cTnT quantification in the potential presence of skTnT in a sample by providing the embodiments as recited in the claims.

[0009] In particular, the present invention relates to a method of determining the amount of cardiac Troponin T (cTnT) in a sample, said method comprising the steps of a) contacting the sample with an antibody against cTnT (anti-cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT.

[0010] When trying to precisely and reliably quantify a target protein like a troponin, commonly applied and well-established approaches can be substantially grouped into two strategies, as it can be observed, e.g., in case of cTnI assays. In particular, assays can be optimized by designing an antibody or an antibody pair with improved specificity compared to current ones and / or by combining several antibodies or antibody pairs for improving assay specifications in case of proteins sharing highly homologous sequences as in case of troponins.

[0011] In contrast to these commonly applied strategies, the inventors surprisingly found that a highly sensitive and precise cTnT quantification can be ensured by adding an anti-skTnT antibody as a scavenger antibody to a, e.g. commercially available, cTnT quantification assay like the Elecsys® cTnT-hs assay. The scavenger antibody has the peculiarity of being designed to be capable of binding to a conserved skTnT peptide sequence while not being capable of binding to the respective (e.g. homologous) cTnT counterpart and thus, the respective conserved cTnT peptide sequence. This approach has several advantages. For example, an anti-cTnT antibody for cTnT quantification may commonly be designed to be capable of binding to a cTnT peptide sequence and / or epitope positioned in a region within the cTnT peptide sequence that is less affected by mutation, degradation and / or modification. The underlying consideration is that such a region is considered more stable compared to other regions within the cTnT sequence. However, such a stable region may represent also a region that is conserved across troponins. In view of the latter, currently available cTnT quantification assays may be affected by some read- out bias caused by an interference with skTnT. It is to be noted, that there appeared to be no high affinity monoclonal anti-skTnT antibody available so far. Remarkably, the inventors were able to successfully design anti-skTnT antibodies with high affinity and high specificity, leveraging themas scavenger antibodies in an anti-cTnT antibody based cTnT quantification assay. Surprisingly, the inventors found that despite the high level of sequence identity and / or homology between cTnT and skTnT in conserved regions between these peptides, respective conserved peptide sequences can be explicitly and successfully leveraged to specifically block binding of available anti-cTnT antibodies to skTnT. Moreover, as said conserved peptide sequences represent comparatively stable regions not only within cTnT but also within skTnT, any potentially interfering effect of (e.g. full-length, mutated, modified and / or degraded) skTnT for cTnT quantification can be avoided. Furthermore, by quantifying cTnT in the presence of the scavenger antibody in a concentration of at least 0.10 mg / mL, concentration dependent interference effects can be overcome. A further beauty of the principle underlying the present invention lays in the fact that the scavenger antibody can be easily added to existing cTnT quantification assays either by “updating” current assay formulations by adding said scavenger antibody before packaging the respective formulation or by providing an additional formulation comprising said scavenger antibody, wherein said additional formulation can be added to the sample before the sample’s amount of cTnT is quantified - if desired and / or required. Thus, in case a cTnT quantification is envisioned in a cost-sensitive manner and / or in the absence of any hint towards a (potentially) elevated skTnT level in said sample, current assays may be performed as usual, whereas the use of the scavenger antibody may be considered especially whenever it is impossible to securely rule out any (potentially) elevated skTnT level in the sample. Consequently, the scavenger antibody can ensure reliable, reproducible and high-sensitive cTnT quantification using currently available cTnT quantification assays without requiring information about a sample´s background. This may be advantageous in case of undiagnosed or suspected SMD as well as especially in case of point of care applications, in which, often in the absence of further information, quick decisions have to be made concerning diagnosis of a cardiac disease like AMI and respective treatment options. Thus, also without knowing whether a subject presenting with symptoms of a cardiac disease was running a marathon before or having been under a drug treatment like a statin-treatment, ICI-treatment and / or anti-VEGF-treatment may no longer give rise to potential false-positives concerning cardiac disease diagnosis based on an elevated cTnT level in the presence of skTnT in the sample. Hence, by leveraging conserved peptide sequence the presence of the scavenger antibody successfully prevents binding of an anti-cTnT antibody used for cTnT quantification in a respective assay to a conserved region in a (e.g. homologous) skTnT peptide sequence and may even result in an anti-cTnT antibody displacement reaction. Thus, the present invention provides means and methods for precisely quantifying cTnT in a sample in the (potential, suspected or known) presence of skTnT.DETAILED DESCRIPTION OF THE INVENTION

[0012] Herein, the amount of cTnT in a sample under study is determined using an anti- cTnT antibody. In this regard, the skilled artisan is aware of the fact that the term “determining the amount of cTnT” and respective grammatical versions thereof may also be understood as “quantifying the amount of cTnT” or “quantifying cTnT”.

[0013] Herein, the determination of the amount of cTnT in a sample under study is based on an anti-cTnT antibody based approach. For example, commercially available cTnT quantification assays may be based on the detection of a signal indicative for the amount of cTnT, wherein said signal may be obtained from a labelled anti-cTnT antibody when bound to an immobilized cTnT. In particular, cTnT comprised in a sample may be immobilized on a surface using an anti-cTnT immobilization antibody (also referred to, e.g., as “capture” antibody). A labelled anti-cTnT antibody (also referred to, e.g., as “detection” antibody) may bind to the immobilized cTnT and after a washing step a signal obtained from the label of the detector antibody may be indicative for the amount of cTnT in the sample. Such approaches may also be referred to as “sandwich assays” (as employed, e.g., in case of the Elecsys® cTnT-hs assay) as the target cTnT is bound by two anti-cTnT antibodies for signal read-out, namely the anti-cTnT immobilization antibody and the labelled anti-cTnT antibody used for signal read-out. Herein, the term “anti-cTnT antibody” may refer to an anti-cTnT immobilization antibody or a labelled anti- cTnT antibody in a sandwich assay setting, preferably to the labelled anti-cTnT antibody (used for cTnT detection, and thus the “detection” antibody). For example, in case of the Elecsys® cTnT- hs assay, the anti-cTnT antibody may be the M11.7 antibody (used in the assay as biotinylated “capture” antibody) or the M7 antibody (used in the assay as “detection” antibody), preferably the anti-cTnT antibody is the M11.7 antibody. While preventing binding of one of the two anti-cTnT antibodies of a sandwich assay for cTnT quantification to skTnT has been shown by the inventors to be sufficient to avoid a potential interference of the respective anti-cTnT antibody with skTnT, the skilled person is aware that also more than one scavengers may be applied, for example one scavenger per anti-cTnT antibody such as, e.g. in case of a sandwich assay setting one scavenger for an anti-cTnT immobilization antibody and one scavenger for a labelled anti-cTnT antibody. Herein, it is preferred that one scavenger antibody is added to a cTnT quantification assay for quantifying cTnT in the (potential, suspected or known) presence of skTnT using an anti-cTnT antibody, wherein in case of a sandwich assay (like, e.g., the Elecsys® cTnT-hs assay) said anti-cTnT antibody may refer to the capture and / or the detection anti-cTnT antibody, preferably to the capture antibody.

[0014] Herein, cardiac Troponin T preferably refers to human cTnT. Human cTnT may refer to the canonical full length cTnT encoded by the gene TNNT2. In the context of the presentinvention it is preferred that cTnT has the sequence set forth in SEQ ID NO: 1. The sequence set forth in SEQ ID NO: 1 is given in Table 1. Said sequence has a total length of 298 amino acids and corresponds to the canonical full length cTnT sequence as laid down in the UniProt database entry P45379 at the time of the filing of the present application. Nevertheless, it is understood by the skilled artisan that herein the term “cTnT” encompasses also isoforms of cTnT, e.g. in case of human cTnT the 12 isoforms as laid down in the UniProt database entry P45379 at the time of the filing of the present application and / or derivatives thereof. Such derivatives may encompass mutated sequences as e.g. found naturally in samples under study, e.g. in case of samples obtained from subjects, as well as (e.g. post-translationally) modified and / or degraded forms of the canonical full length cTnT sequence or any of its isoforms. While positions and (e.g. conserved) peptide sequences of cTnT are given herein for the canonical full length cTnT sequence as the preferred cTnT reference sequence, the skilled artisan is well aware of means and methods to transfer knowledge about said positions and peptide sequences to cTnT isoforms and derivatives thereof. Table 1: Sequences described herein. cTnT: cardiac Troponin T, sskTnT: slow skeletal Troponin T, fskTnT: fast skeletal Troponin T, CDR: complementarity-determining region, VH: heavy chain variable region, VL: light chain variable region. It is to be noted that CDR, VH and VL sequences refer to respective antibody sequences. SEQ ID Type Sequence NO: 1 cTnT MSDIEEVVEEYEEEEQEEAAVEEEEDWREDEDEQEEAAEEDAE AEAETEETRAEEDEEEEEAKEAEDGPMEESKPKPRSFMPNLVPP KIPDGERVDFDDIHRKRMEKDLNELQALIEAHFENRKKEEEELVS LKDRIERRRAERAEQQRIRNEREKERQNRLAEERARREEEENRR KAEDEARKKKALSNMMHFGGYIQKQAQTERKSGKRQTEREKKK KILAERRKVLAIDHLNEDQLREKAKELWQSIYNLEAEKFDLQEKFK QQKYEINVLRNRINDNQKVSKTRGKAKVTGRWK 2 sskTnT MSDTEEQEYEEEQPEEEAAEEEEEAPEEPEPVAEPEEERPKPSR PVVPPLIPPKIPEGERVDFDDIHRKRMEKDLLELQTLIDVHFEQRK KEEEELVALKERIERRRSERAEQQRFRTEKERERQAKLAEEKMR KEEEEAKKRAEDDAKKKKVLSNMGAHFGGYLVKAEQKRGKRQT GREMKVRILSERKKPLDIDYMGEEQLRARSAWLPPSQPSCPARE KAQELSDWIHQLESEKFDLMAKLKQQKYEINVLYNRISHAQKFRK GAGKGRVGGRWK 3 fskTnT MSDEEVEQVEEQYEEEEEAQEEAAEVHEEVHEPEEVQEDTAEE DAEEEKPRPKLTAPKIPEGEKVDFDDIQKKRQNKDLMELQALIDS HFEARKKEEEELVALKERIEKRRAERAEQQRIRAEKERERQNRLA EEKARREEEDAKRRAEDDLKKKKALSSMGANYSSYLAKADQKR GKKQTAREMKKKILAERRKPLNIDHLGEDKLRDKAKELWETLHQL EIDKFEFGEKLKRQKYDITTLRSRIDQAQKHSKKAGTPAKGKVGG RWK 4 cTnT AEQQRIRNEREKERQNRLAEER peptide 5 sskTnT AEQQRFRTEKERERQAKLAEEK peptidefskTnT AEQQRIRAEKERERQNRLAEEK peptide CDR-H1 monoclo nal Ab A GFSFNRYYIC CDR-H2 monoclo nal Ab A CINGGSTGSTAYASWARG CDR-H3 monoclo nal Ab A DDNAYDYMDL CDR-L1 monoclo nal Ab A QASQSLGSNLA CDR-L2 monoclo nal Ab A YPANLAS CDR-L3 monoclo nal Ab A QGPYYNDGVNP CDR-H1 monoclo nal Ab C GIDFSSGYYMC CDR-H2 monoclo nal Ab C CIYTGDGVTYYASWVNG CDR-H3 monoclo nal Ab C DADIVGSGAAFDP CDR-L1 monoclo nal Ab C QASQSISSYLA CDR-L2 monoclo nal Ab C AASNLAS CDR-L3 monoclo nal Ab C QCTDYASSFT CDR-H1 monoclo nal Ab B GFTISSDYDMC CDR-H2 monoclo nal Ab B AIYGGSSGSTYYASWAKG CDR-H3 monoclo nal Ab B AGDYAFGL CDR-L1 monoclo nal Ab B QSRQTVLNNNDLA CDR-L2 monoclo nal Ab B KASTLAS CDR-L3 monoclo nal Ab B QGEFSCSSVDCYAVH QEQLEESGGDLVKPEGSLTLTCTASGFSFNRYYICWVRQAPGKG monoclo LEWIACINGGSTGSTAYASWARGRLTISKTSSTTVTLQMTSLTAA nal Ab A DTATYFCARDDNAYDYMDLWGPGTLVTVSS VH HQQLEESGGGLVKPGGTLTLACKASGIDFSSGYYMCWVRQAPG monoclo KGLEWIACIYTGDGVTYYASWVNGRFTISRSTSLNTVDLKMTSLT nal Ab C AADTATYFCARDADIVGSGAAFDPWGPGTLVTVSS VH QEHLEESGGDLVKPEGSLTLTCTASGFTISSDYDMCWVRQAPGK monoclo GLEWIAAIYGGSSGSTYYASWAKGRFTISKTSSTTVTLQMTSLTA nal Ab B ADTATYFCARAGDYAFGLWGPGTLVTVSS VL DVVMTQTPASVSEPVGGTVTIKCQASQSLGSNLAWYQQKPGQP monoclo PKLLIYYPANLASGVPSRFSGSGSGTEYTLTISDLECDDAATYYC nal Ab A QGPYYNDGVNPFGGGTEVVVK VL NVVMTQTPASVSEPVGGTVTIKCQASQSISSYLAWYQQKPGQPP monoclo KLLIYAASNLASGVSSRFKGSRSGTQFTLTISDLECADAATYYCQ nal Ab C CTDYASSFTFGGGTEVVVK VL QVLTQTPSPVSAAVGGTVTINCQSRQTVLNNNDLAWYQQKPGQ monoclo RPKLLIYKASTLASGVSSRFKGSGSGTQFTLTISGVQCDDAATYY nal Ab B CQGEFSCSSVDCYAFGGGTEVVVK cTnT PKPRSFMPNLVPPKIPDGE peptide sskTnT PKPSRPVVPPLIPPKIPEGE peptide fskTnT PRPKLTAPKIPEGE peptide cTnT MHFGGYIQKQAQTERKS peptide sskTnT GAHFGGYLVKAEQKR peptide fskTnT GANYSSYLAKADQKR peptide TNNT3a EDTAEEDAEEEKPRPKLTAPKIPEGEKVDFDDIQKKRQN (38-76) (fsk TnT aa38-76) TNNT3b AEQQRIRAEKERERQNRLAEEKARREEEDAKRRAEDDLKKKKAL (115- SSMGANYSSYLAKADQK 176) (fskTnT aa 115- 176) TNNT3c RIEKRRAERAEQQRIRAEKERERQNRLAEEKARREEEDAKR (106- 146) (fskTnT aa 106- 146) TNNT3d RIEKRRAERAEQQRIRAEKERERQNRLAEEKARREEEDAKRRAE (106- DDLKKKKALSSMGANYSSYLAKADQKRGKKQTAREMK 186) (fskTnT aa106- 186) TNNT3e AEDDLKKKKALSSMGANYSSYLAKADQKRGKKQTAREMK (148- 186) (fskTnTaa148- 186) TNNT1a PVAEPEEERPKPSRPVVPPLIPPKIPEGERVDFDDIHRKR (31-70) (sskTnT aa 31- 70) TNNT1b PKPSRPVVPPLIPPKIPEGERVDFDDIHRKRMEKDLLELQTLIDVH (40-132) FEQRKKEEEELVALKERIERRRSERAEQQRFRTEKERERQAKLA (sskTnT EEK aa 40- 132) TNNT1c RIERRRSERAEQQRFRTEKERERQAKLAEEKMRKEEEEAK (102- 141) (sskTnT aa 102- 141) TNNT1d AKKKKVLSNMGAHFGGYLVKAEQKRGKRQTGREMKVR (148- 184) (sskTnT aa 148- 184) SEQ ID AEQQRFRTEKERERQAKLAEEK-bAla-Acp-bAla-Cys No 5 with C- terminal ßAla- Ahx- ßAla-Cys SEQ ID AEQQRIRAEKERERQNRLAEEK-bAla-Acp-bAla-Cys No 6 with C- terminal ßAla- Ahx- ßAla-Cys SEQ ID PKPSRPVVPPLIPPKIPEGE-bAla-Acp-bAla-Cys No 32 with C- terminal ßAla- Ahx- ßAla-Cys SEQ ID PRPKLTAPKIPEGE-bAla-Acp-bAla-Cys No 33 with C- terminal ßAla- Ahx- ßAla-Cys SEQ ID GAHFGGYLVKAEQKR-bAla-Acp-bAla-Cys No 35 with C-terminal ßAla- Ahx- ßAla-Cys SEQ ID GANYSSYLAKADQKR-bAla-Acp-bAla-Cys No 36 with C- terminal ßAla- Ahx- ßAla-Cys SEQ ID bAla-AEQQRIRNEREKERQNRLAEER No 4 with N- terminal ßAla for PEG3- Biotin linking SEQ ID bAla-AEQQRFRTEKERERQAKLAEEK No 5 with N- terminal ßAla for PEG3- Biotin linking SEQ ID bAla-AEQQRIRAEKERERQNRLAEEK No 6 with N- terminal ßAla for PEG3- Biotin linking SEQ ID bAla-PKPRSFMPNLVPPKIPDGE No 31 with N- terminal ßAla for PEG3- Biotin linking SEQ ID bAla-PKPSRPVVPPLIPPKIPEGE No 32 with N- terminal ßAla for PEG3- Biotin linking SEQ ID bAla-PRPKLTAPKIPEGE No 33 with N- terminal ßAla forPEG3- Biotin linking 58 SEQ ID bAla-MHFGGYIQKQAQTERKS No 34 with N- terminal ßAla for PEG3- Biotin linking 59 SEQ ID bAla-GAHFGGYLVKAEQKR No 35 with N- terminal ßAla for PEG3- Biotin linking 60 SEQ ID bAla-GANYSSYLAKADQKR No 36 with N- terminal ßAla for PEG3- Biotin linking 61 C- bAla-Acp-bAla-Cys terminal ßAla- Ahx- ßAla-Cys

[0015] Herein, the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence).

[0016] Sequence conservation may refer to identical or similar sequences in nucleic acids (DNA and / or RNA) or proteins across species and thus, across orthologous sequences, or within a genome. A sequence position and / or a region (subsequence) within a sequence may be conserved due to selective pressure. Accordingly, conserved sequences like conserved peptide sequences may be identified and / or defined based on estimates of selective pressure like the ratio of non-synonymous substitution rate to synonymous substitution rate. Additionally or alternatively, (e.g. pairwise or multiple, preferably multiple) sequence alignments may be used to determine sequence position(s) and / or region(s) conserved between said sequences used for the alignment based on sequence identity, similarity and / or substitution (matrix). Examples of software suitable for performing a sequence alignment may be software programs like Clustal Omega and the like (cf. e.g. services provided by EMBL-EBI).

[0017] As troponin protein sequences may exhibit evolutionarily conserved sites. For example, Shakur et al. (NPJ Genom Med.2021 Jun 14;6(1):47. doi: 10.1038 / s41525-021-00204- w) studied the conservation of amino acids in TnC, TnT and TnI across species and found that the protein sequences were highly conserved except in their N-termini. As regards the protein sequence of cTnT it was concluded that compared to the rest of TnT, the 75 N-terminal amino acids appeared to be least conserved across species. Taking a closer look at the details given in the article’s Supplementary Figure 1c it can be seen that indeed the 73 N-terminal amino acids of TnT appear to be least conserved across species. Hence, it is herein understood that the conserved cTnT peptide sequence consists of amino acids 74 to 298 of SEQ ID NO: 1. Accordingly, the anti-cTnT antibody may be capable of binding to (e.g. an epitope within) the conserved cTnT peptide sequence consisting of amino acids 74 to 298 of SEQ ID NO: 1. This has the advantage that cTnT can be quantified stably and comprehensively. For example, in case of the Elecsys® cTnT-hs assay, cTnT can be quantified stably and highly sensitive using the M7 antibody and / or the M11.7 antibody.

[0018] Preferably, the conserved cTnT peptide sequence comprises a cTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 4. Said sequence is given in Table 1. Said sequence may comprise a peptide sequence and / or an epitope recognized for example by commercially available anti-cTnT antibodies, e.g. comprised in cTnT quantification assays. Accordingly, it is preferred that the anti-cTnT antibody is capable of binding to an epitope within a cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 4. This has the advantage of resembling at least a subset of currently available anti- cTnT antibodies, e.g. employed in cTnT quantification assays, as well as of enabling a stable and / or comprehensive quantification cTnT; for example, in case of the Elecsys® cTnT-hs assay, the (“capture”) M11.7 antibody. Additionally or alternatively, the conserved cTnT peptide sequence may comprise a cTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 31 and / or SEQ ID NO: 34. In this case, the anti-cTnT antibody may be capable of binding to an epitope within a cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 31 and / or SEQ ID NO: 34.

[0019] In view of the basic principle underlying the present invention, namely blocking of a potentially occurring binding of an anti-cTnT antibody to skTnT using an anti-skTnT antibody as a scavenger antibody, it is required herein that the anti-skTnT antibody is not capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), while the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. For example, it may be preferred that the conserved skTnT peptide sequence is homologous to the conserved cTnT peptide sequence. Furthermore,said blocking may be realized by various means and methods. By selecting an epitope of the anti- skTnT antibody and an epitope of the anti-cTnT antibody that are used in the method described herein, it may be possible to assure prevention of binding of the anti-cTnT antibody to skTnT. For example, the selection of said epitopes may assure that binding of the anti-skTnT antibody to skTnT sterically prevents binding of the anti-cTnT antibody to skTnT. For example, the method described herein may further comprise a step of selecting an anti-cTnT antibody capable of binding cTnT and / or selecting an anti-skTnT antibody capable of preventing binding of an anti- cTnT antibody to skTnT. Thus, an anti-skTnT antibody may be selected such that said antibody may prevent binding of an anti-cTnT antibody to skTnT. For example, the anti-cTnT antibody and the anti-skTnT antibody may bind to non-overlapping and / or spatially distant peptide sequences and / or epitopes within the conserved skTnT peptide sequence under the condition that binding of the anti-skTnT antibody spatially prevents binding of the anti-cTnT antibody to skTnT. Such a spatial binding prevention may be direct, e.g. by not leaving enough space for the anti-cTnT antibody to bind to skTnT when the anti-skTnT antibody is bound to skTnT, and / or indirect, e.g. by a conformational change upon the anti-skTnT antibodies binding to skTnT that spatially prevents binding of the anti-cTnT antibody to skTnT. Accordingly, it may be preferred that binding of the anti-cTnT antibody to skTnT is prevented by steric inhibition when the anti-skTnT antibody is bound to the conserved skTnT peptide sequence. Additionally or alternatively, the anti-cTnT antibody and the anti-skTnT antibody may have (e.g. at least partially) overlapping or even identical epitopes within the conserved skTnT peptide sequence, whereby e.g. the epitope capable of being bound by the anti-cTnT antibody may be spatially at least partially covered due to the binding of the anti-skTnT antibody to skTnT. Thus, it may be preferred that the anti-skTnT antibody is capable of binding to an epitope comprised in the conserved skTnT peptide sequence (skTnT epitope), preferably wherein i) the skTnT epitope shares at least 75% sequence identity to a homologous peptide sequence in cTnT, and / or wherein ii) the anti-cTnT antibody is capable of binding to an epitope within the conserved cTnT peptide sequence (cTnT epitope) and wherein the skTnT epitope comprises and / or is at least partially overlapping with a peptide sequence within skTnT that is homologous to the cTnT epitope. For example, the skTnT epitope may share at least 75% sequence identity or at least 80%, at least 85%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, at least 99.5%, at least 99.9% or 100% sequence identity to a homologous peptide sequence in cTnT. For example, the skTnT epitope may be less than 15 Ångström (Å), preferably less than 10 Å, more preferably less than 9 Å, distant from a sequence within skTnT that is homologous to the cTnT epitope. For example, the skTnT epitope may be less than 11 amino acid residues, preferably less than 8 amino acid residues, more preferably less than 7 amino acid residues, distant from a sequence within skTnT that is homologous to the cTnT epitope. Thus, blocking of a potentially occurring binding of an anti-cTnT antibody to skTnT may be realized by at least partially masking and / or at least spatially coveringthe anti-cTnT antibodies epitope within the conserved skTnT peptide sequence by the binding of the scavenger antibody. Hence, when realizing blocking of a potentially occurring binding of an anti-cTnT antibody to skTnT using a scavenger antibody, binding of the anti-cTnT antibody to the conserved skTnT peptide sequence can be prevented. This has the advantage that the addition of the scavenger antibody to a cTnT quantification assay does not (substantially) affect the cTnT quantification using the anti-cTnT antibody, while reducing the risk of potential interference of the anti-cTnT antibody with skTnT. Herein, it is preferred that the anti-cTnT antibody and the anti- skTnT antibody have at least partially overlapping skTnT epitope and peptide sequence within skTnT homologous to the cTnT epitope.

[0020] Accordingly, the anti-skTnT antibody is not capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence) and is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby (being capable of) preventing binding of the anti-cTnT antibody to skTnT. For example, the anti-skTnT antibody may not be capable of binding to (e.g. an epitope within) the conserved cTnT peptide sequence consisting of amino acids 74 to 298 of SEQ ID NO: 1. For example, the anti-skTnT antibody may not be capable of binding to an epitope within a cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 4. Thus, potential interferences of an anti-skTnT antibody with cTnT can be avoided, especially when the conserved cTnT peptide sequence consists of amino acids 74 to 298 of SEQ ID NO: 1 and of the sequence set forth in SEQ ID NO: 4, respectively. Additionally or alternatively, the anti-skTnT antibody may not be capable of binding to an epitope within a cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 31 and / or in SEQ ID NO: 34. This may be advantageous especially in case the conserved cTnT peptide sequence comprises a cTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 31 and / or SEQ ID NO: 34. For example, the anti-skTnT antibody may not be capable of binding to an epitope within a cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 31 and of binding to an epitope within a cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 34.

[0021] Preferably, the anti-skTnT antibody is not capable of binding to cTnT.

[0022] As regards skeletal Troponin T, it is preferred that skTnT refers herein to human skTnT. Human skTnT may refer to the canonical full length slow and fast skTnT encoded by the gene TNNT1 and TNNT3, respectively. In the context of the present invention it is preferred that skTnT has the sequence set forth in SEQ ID NO: 2 and / or 3. Said sequences are given in Table 1. In particular, the sequence set forth in SEQ ID NO: 2 has a total length of 278 amino acids, and its sequence corresponds to the canonical full length slow skTnT (sskTnT) sequence as laiddown in the UniProt database entry P13805 at the time of the filing of the present application. The sequence set forth in SEQ ID NO: 3 has a total length of 269 amino acids, and its sequence corresponds to the canonical full length fast skTnT (fskTnT) sequence as laid down in the UniProt database entry P45378 at the time of the filing of the present application. Nevertheless, it is understood by the skilled artisan that herein term “skTnT” encompasses also isoforms of skTnT, e.g. in case of human sskTnT the 3 isoforms laid down in the UniProt database entry P13805 at the time of the filing of the present application and / or derivatives thereof as well as in case of human fskTnT the 7 isoforms laid down in the UniProt database entry P45378 at the time of the filing of the present application and / or derivatives thereof. Derivatives may encompass mutated sequences as e.g. found naturally in samples under study, e.g. in case of samples obtained from human subjects, as well as (e.g. post-translationally) modified and / or degraded forms of the respective canonical full length skTnT sequence or any of its isoforms. While positions and (e.g. conserved) peptide sequences of skTnT are given herein for the canonical full length sskTnT and fskTnT sequence as the preferred sskTnT and fskTnT reference sequence, respectively, the skilled artisan is well aware of means and methods to transfer knowledge about said positions and peptide sequences to sskTnT isoforms and derivatives thereof and fskTnT isoforms and derivatives thereof, respectively.

[0023] Preferably, the conserved skTnT peptide sequence consists of i) amino acids 40 to 278 of SEQ ID NO: 2 (sskTnT), and / or ii) amino acids 44 to 269 of SEQ ID NO: 3 (fskTnT). This may be advantageous in case the conserved cTnT peptide sequence consists of amino acids 74 to 298 of SEQ ID NO: 1 as the conserved skTnT peptide sequence thus (substantially) corresponds to said conserved cTnT peptide sequence. In this case, said conserved peptide sequences refer to peptide sequences being conserved in homologous skTnT and cTnT. Accordingly, the anti-skTnT antibody is preferably capable of binding to i) (e.g. an epitope within) the conserved skTnT peptide sequence consisting of amino acids 40 to 278 of SEQ ID NO: 2 (sskTnT), and / or ii) (e.g. an epitope within) the conserved skTnT peptide sequence consisting of amino acids 44 to 269 of SEQ ID NO: 3 (fskTnT). Preferably, the anti-skTnT antibody is capable of binding to both the conserved sskTnT peptide sequence consisting of amino acids 40 to 278 of SEQ ID NO: 2 and to the conserved fskTnT peptide sequence consisting of amino acids 44 to 269 of SEQ ID NO: 3. For example, the anti-skTnT antibody may be capable of binding to both an epitope within the conserved sskTnT peptide sequence consisting of amino acids 40 to 278 of SEQ ID NO: 2 and to an epitope within the conserved fskTnT peptide sequence consisting of amino acids 44 to 269 of SEQ ID NO: 3.

[0024] Preferably, the conserved skTnT peptide sequence comprises i) a slow skTnT (sskTnT) peptide sequence consisting of the sequence set forth in SEQ ID NO: 5, and / or ii) a fast skTnT (fskTnT) peptide sequence consisting of the sequence set forth in SEQ ID NO: 6. This mayespecially be advantageous in case the conserved cTnT peptide sequence consists of the sequence set forth in SEQ ID NO: 4 and thus, in case the conserved skTnT peptide sequence(s) (substantially) correspond(s) to said conserved cTnT peptide sequence. Thus, said conserved peptide sequences may refer to peptide sequences being conserved in homologous skTnT and cTnT. Accordingly, the anti-skTnT antibody is preferably capable of binding to an epitope within i) a sskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 5, and / or within ii) an fskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 6. Preferably, the anti-skTnT antibody is capable of binding both to an epitope within the sskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 5 and to an epitope within the fskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 6. The respective sequences are given in Table 1. Additionally or alternatively, the conserved skTnT peptide sequence may comprise i) an sskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 32, and / or ii) a fskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 33. This may especially be advantageous in case the conserved cTnT peptide sequence consists of the sequence set forth in SEQ ID NO: 31 and thus, in case the conserved skTnT peptide sequence(s) (substantially) correspond(s) to the homologues conserved cTnT peptide sequence. Accordingly, the anti-skTnT antibody may be capable of binding to an epitope within i) a sskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 32, and / or within ii) an fskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 33. Preferably, the anti-skTnT antibody is capable of binding both to an epitope within the sskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 32 and to an epitope within the fskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 33. Additionally or alternatively, the conserved skTnT peptide sequence may comprise i) an sskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 35, and / or ii) a fskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 36. This may especially be advantageous in case the conserved cTnT peptide sequence consists of the sequence set forth in SEQ ID NO: 34 and thus, in case the conserved skTnT peptide sequence(s) (substantially) correspond(s) to the homologous conserved cTnT peptide sequence. Accordingly, the anti-skTnT antibody may be capable of binding to an epitope within i) a sskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 35, and / or within ii) an fskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 36. Preferably, the anti-skTnT antibody is capable of binding both to an epitope within the sskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 35 and to an epitope within the fskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 36.

[0025] In view of the basic principle underlying the present invention, namely preventing binding of the anti-cTnT antibody to the conserved skTnT peptide, it is preferred that the anti- cTnT antibody is not capable of binding to an epitope within the skTnT peptide sequence(s) (comprised in the conserved skTnT peptide sequence(s)) as set forth in SEQ ID NO: 5 and / or SEQ ID NO: 6 in the presence of the anti-skTnT antibody. Preferably, the anti-cTnT antibody is, in the presence of the anti-skTnT antibody, not capable of binding to both an epitope within said skTnT peptide sequence as set forth in SEQ ID NO: 5 and to an epitope within said skTnT peptide sequence as set forth in SEQ ID NO: 6. This may especially be advantageous in case the conserved cTnT peptide sequence consists of the sequence set forth in SEQ ID NO: 4. Additionally or alternatively, the anti-cTnT antibody may not be capable of binding to an epitope within the skTnT peptide sequence(s) (comprised in the conserved skTnT peptide sequence(s)) as set forth in SEQ ID NO: 32 and / or SEQ ID NO: 33 in the presence of the anti-skTnT antibody. This may be advantageous in case the conserved cTnT peptide sequence consists of the sequence set forth in SEQ ID NO: 31. Additionally or alternatively, the anti-cTnT antibody may not be capable of binding to an epitope within the skTnT peptide sequence(s) (comprised in the conserved skTnT peptide sequence(s)) as set forth in SEQ ID NO: 35 and / or SEQ ID NO: 36 in the presence of the anti-skTnT antibody. This may be advantageous in case the conserved cTnT peptide sequence consists of the sequence set forth in SEQ ID NO: 34.

[0026] Preferably, the conserved cTnT peptide sequence comprises a cTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 4 and the anti-cTnT antibody is capable of binding to an epitope within said cTnT peptide sequence and the anti-skTnT antibody is not capable of binding to an epitope within said cTnT peptide (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 4. Additionally or alternatively, it may be preferred that the conserved skTnT peptide sequence comprises i) a sskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 5, and / or ii) a fskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 6, and that the anti-skTnT antibody is capable of binding to an epitope within the i) sskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 5, and / or within ii) fskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 6, while preferably the anti- cTnT antibody is not capable of binding to an epitope within said skTnT peptide sequence (comprised in the conserved skTnT peptide sequence(s)) as set forth in SEQ ID NO: 5 and / or SEQ ID NO: 6, respectively, in the presence of the anti-skTnT antibody. For example, the conserved cTnT peptide sequence may comprise a cTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 4 and the anti-cTnT antibody may be capable of binding to an epitope within said cTnT peptide sequence in contrast to the anti-skTnT antibody, and the conserved skTnT peptide sequence may comprise a sskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 5, and the anti-skTnT antibody may be capable of binding toan epitope within said sskTnT peptide sequence in contrast to the anti-cTnT antibody in the presence of said anti-skTnT antibody. For example, the conserved cTnT peptide sequence may comprise a cTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 4 and the anti-cTnT antibody may be capable of binding to an epitope within said cTnT peptide sequence in contrast to the anti-skTnT antibody, and the conserved skTnT peptide sequence may comprise a fskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 6, and the anti- skTnT antibody may be capable of binding to an epitope within said fskTnT peptide in contrast to the anti-cTnT antibody in the presence of said anti-skTnT antibody. For example, the conserved cTnT peptide sequence may comprise a cTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 4 and the anti-cTnT antibody may be capable of binding to an epitope within said cTnT peptide sequence in contrast to the anti-skTnT antibody, and the conserved skTnT peptide sequence may comprise a sskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 5 and of a fskTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 6, and the anti-skTnT antibody may be capable of binding to an epitope within said sskTnT peptide and to an epitope within said fskTnT peptide sequence (comprised in the conserved fskTnT peptide sequence(s)) as set forth in SEQ ID NO: 5 and / or SEQ ID NO: 6, respectively) in contrast to the anti-cTnT antibody in the presence of said anti-skTnT antibody.

[0027] As regards the anti-skTnT antibody, it is preferred that the anti-skTnT antibody is present in a concentration of at least 0.10 mg / mL, or of at least 0.15 mg / mL, or of at least 0.20 mg / mL, or of at least 0.25 mg / mL. The anti-skTnT antibody may be present in a concentration between 0.10 mg / mL and 30 mg / mL, or between 0.10 mg / mL and 20 mg / mL, or between 0.15 mg / mL and 15 mg / mL, or between 0.20 mg / mL and 10 mg / mL, or between 0.20 mg / mL and 0.50 mg / mL. Preferably, the anti-skTnT antibody is present in a concentration between 0.10 mg / mL and 20 mg / mL or between 0.10 mg / mL and 30 mg / mL.

[0028] Additionally or alternatively, binding of an antibody to a peptide or protein may be described by defining the epitope the antibody binds to or is capable of binding to. Herein, the term “epitope” has the common meaning in the art and may thus refer to the (preferably specific) binding site of an antibody within a target sequence, wherein the epitope may be conformational and / or linear. An epitope may comprise for example between 1 and 20 amino acid residues, e.g. between 2 and 15 or e.g. between 4 and 12 amino acid residues.

[0029] Preferably, the anti-cTnT antibody is capable of binding to an epitope within cTnT, wherein said cTnT epitope comprises one or more amino acid positions of cTnT, (said cTnT) having the sequence set forth in SEQ ID NO: 1, selected from the group consisting of 152, 154, 156 and 166, and wherein at said one or more positions the amino acid is N 152, R 154, K 156, and / or R 166. Thus, when cTnT has the sequence set forth in SEQ ID NO: 1, the anti-cTnTantibody is preferably capable of binding to an epitope within cTnT comprising one or more of N 152, R 154, K 156, and / or R 166.

[0030] Preferably, the anti-cTnT antibody is capable of binding to an epitope within cTnT, wherein said cTnT epitope comprises one or more amino acid positions of cTnT, (said cTnT) having the sequence set forth in SEQ ID NO: 1, selected from the group consisting of 154, 156 and 166, and wherein at said one or more positions the amino acid is R 154, K 156, and / or R 166. Thus, when cTnT has the sequence set forth in SEQ ID NO: 1, the anti-cTnT antibody is preferably capable of binding to an epitope within cTnT comprising one or more of R 154, K 156, and / or R 166.

[0031] As regards the anti-skTnT antibody, it is accordingly preferred that the anti-skTnT antibody is capable of binding to an epitope within sskTnT, wherein said sskTnT epitope comprises one or more amino acid positions of sskTnT, (said sskTnT) having the sequence set forth in SEQ ID NO: 2, selected from the group consisting of 118, 120, 122 and 132, and wherein at said one or more positions the amino acid is not N 118, R 120, K 122, and / or R 132.

[0032] Preferably, the anti-skTnT antibody is capable of binding to an epitope within sskTnT, wherein said sskTnT epitope comprises one or more amino acid positions of sskTnT, (said sskTnT) having the sequence set forth in SEQ ID NO: 2, selected from the group consisting of 120, 122 and 132, and wherein at said one or more positions the amino acid is not R 120, K 122, and / or R 132.

[0033] Preferably, the anti-skTnT antibody is capable of binding to an epitope within sskTnT, wherein said sskTnT epitope comprises one or more amino acid positions of sskTnT, (said sskTnT) having the sequence set forth in SEQ ID NO: 2, selected from the group consisting of 118, 120, 122 and 132, and wherein said sskTnT epitope comprises at said one or more positions the amino acid(s) T 118, K 120, R 122 and K 132. Thus, when sskTnT has the sequence set forth in SEQ ID NO: 2, the anti-skTnT antibody is preferably capable of binding to an epitope within sskTnT comprising one or more of T 118, K 120, R 122 and K 132.

[0034] Preferably, the anti-skTnT antibody is capable of binding to an epitope within sskTnT, wherein said sskTnT epitope comprises one or more amino acid positions of sskTnT, (said sskTnT) having the sequence set forth in SEQ ID NO: 2, selected from the group consisting of 120, 122 and 132, and wherein said sskTnT epitope comprises at said one or more positions the amino acid(s) K 120, R 122 and K 132. Thus, when sskTnT has the sequence set forth in SEQ ID NO: 2, the anti-skTnT antibody is preferably capable of binding to an epitope within sskTnT comprising one or more of K 120, R 122 and K 132.

[0035] As regards the anti-skTnT antibody, it is preferred that the anti-skTnT antibody is capable of binding to an epitope within fskTnT, wherein said fskTnT epitope comprises one or more amino acid positions of fskTnT, (said fskTnT) having the sequence set forth in SEQ ID NO: 3, selected from the group consisting of 122, 124, 126 and 136, and wherein at said one or more positions the amino acid is not N 122, R 124, K 126, and / or R 136.

[0036] Preferably, the anti-skTnT antibody is capable of binding to an epitope within fskTnT, wherein said fskTnT epitope comprises one or more amino acid positions of fskTnT, (said fskTnT) having the sequence set forth in SEQ ID NO: 3, selected from the group consisting of 124, 126 and 136, and wherein at said one or more positions the amino acid is not R 124, K 126, and / or R 136.

[0037] Preferably, the anti-skTnT antibody is capable of binding to an epitope within fskTnT, wherein said fskTnT epitope comprises one or more amino acid positions of fskTnT, (said fskTnT) having the sequence set forth in SEQ ID NO: 3, selected from the group consisting of 122, 124, 126 and 136, and wherein said fskTnT epitope comprises at said one or more positions the amino acid(s) A 122, K 124, R 126 and K 136. Thus, when fskTnT has the sequence set forth in SEQ ID NO: 3, the anti-skTnT antibody is preferably capable of binding to an epitope within fskTnT comprising one or more of A 122, K 124, R 126 and K 136.

[0038] Preferably, the anti-skTnT antibody is capable of binding to an epitope within fskTnT, wherein said fskTnT epitope comprises one or more amino acid positions of fskTnT, (said fskTnT) having the sequence set forth in SEQ ID NO: 3, selected from the group consisting of 124, 126 and 136, and wherein said fskTnT epitope comprises at said one or more positions the amino acid(s) K 124, R 126 and K 136. Thus, when fskTnT has the sequence set forth in SEQ ID NO: 3, the anti-skTnT antibody is preferably capable of binding to an epitope within fskTnT comprising one or more of K 124, R 126 and K 136.

[0039] Preferably, the anti-skTnT antibody is capable of binding to i) an epitope within sskTnT, wherein said sskTnT epitope comprises one or more amino acid positions of sskTnT, (said sskTnT) having the sequence set forth in SEQ ID NO: 2, selected from the group consisting of 118, 120, 122 and 132, and wherein at said one or more positions the amino acid is not N 118, R 120, K 122, and / or R 132, and to ii) an epitope within fskTnT, wherein said fskTnT epitope comprises one or more amino acid positions of fskTnT, (said fskTnT) having the sequence set forth in SEQ ID NO: 3, selected from the group consisting of 122, 124, 126 and 136, and wherein at said one or more positions the amino acid is not N 122, R 124, K 126, and / or R 136.

[0040] Preferably, the anti-skTnT antibody is capable of binding to i) an epitope within sskTnT, wherein said sskTnT epitope comprises one or more amino acid positions of sskTnT, (said sskTnT) having the sequence set forth in SEQ ID NO: 2, selected from the group consistingof 120, 122 and 132, and wherein said sskTnT epitope comprises at said one or more positions the amino acid(s) K 120, R 122 and K 132, and to ii) an epitope within fskTnT, wherein said fskTnT epitope comprises one or more amino acid positions of fskTnT, (said fskTnT) having the sequence set forth in SEQ ID NO: 3, selected from the group consisting of 124, 126 and 136, and wherein said fskTnT epitope comprises at said one or more positions the amino acid(s) K 124, R 126 and K 136.

[0041] Preferably, the anti-cTnT antibody is capable of binding to an epitope within cTnT (with cTnT having the sequence set forth in SEQ ID NO: 1) comprising i) one or more of N 152, R 154, K 156, and / or R 166, or ii) one or more of R 154, K 156, and / or R 166, and the anti-skTnT antibody is capable of binding to an epitope within sskTnT (with sskTnT having the sequence set forth in SEQ ID NO: 2) comprising i) one or more amino acid positions of sskTnT selected from the group consisting of 118, 120, 122 and 132, wherein the respective amino acid is not N 118, R 120, K 122, and / or R 132, preferably comprising one or more of T 118, K 120, R 122 and K 132, or ii) one or more amino acid positions of sskTnT selected from the group consisting of 120, 122 and 132, wherein the respective amino acid is not R 120, K 122, and / or R 132, preferably comprising one or more of K 120, R 122 and K 132. Additionally or alternatively, the anti-cTnT antibody is capable of binding to an epitope within cTnT (with cTnT having the sequence set forth in SEQ ID NO: 1) comprising i) one or more of N 152, R 154, K 156, and / or R 166, or ii) one or more of R 154, K 156, and / or R 166, and the anti-skTnT antibody is capable of binding to an epitope within fskTnT (with fskTnT having the sequence set forth in SEQ ID NO: 3) comprising i) one or more amino acid positions of fskTnT selected from the group consisting of 122, 124, 126 and 136, wherein the amino acid is not N 122, R 124, K 126, and / or R 136, preferably comprising one or more of A 122, K 124, R 126 and K 136, or ii) one or more amino acid positions of fskTnT selected from the group consisting of 124, 126 and 136, wherein the amino acid is not R 124, K 126, and / or R 136, preferably comprising one or more of K 124, R 126 and K 136. For example, the anti-cTnT antibody may be capable of binding to an epitope within cTnT (with cTnT having the sequence set forth in SEQ ID NO: 1) comprising one or more of N 152, R 154, K 156, and / or R 166, and the anti-skTnT antibody may be capable of binding to a) an epitope within sskTnT (with sskTnT having the sequence set forth in SEQ ID NO: 2) comprising one or more of T 118, K 120, R 122 and K 132, and / or to b) an epitope within fskTnT (with fskTnT having the sequence set forth in SEQ ID NO: 3) comprising one or more of A 122, K 124, R 126 and K 136. For example, the anti-cTnT antibody may be capable of binding to an epitope within cTnT (with cTnT having the sequence set forth in SEQ ID NO: 1) comprising one or more of R 154, K 156, and / or R 166, and the anti-skTnT antibody may be capable of binding to a) an epitope within sskTnT (with sskTnT having the sequence set forth in SEQ ID NO: 2) comprising one or more of K 120, R 122 and K 132, and / or to b) an epitope within fskTnT (with fskTnT having the sequence set forth in SEQ ID NO: 3) comprising one or more of K 124, R 126 and K 136.

[0042] Additionally or alternatively, binding of an antibody to a peptide or protein may be described by defining the binding affinity of the antibody to said peptide or protein. Binding affinity may be measured and reported using the equilibrium dissociation constant (KD), which can be used to evaluate and rank order strengths of bimolecular interactions. The smaller the value of KD, the greater the binding affinity of the antibody for its respective binding target. KDmay be determined, for example, by fluorescence anisotropy or Surface Plasmon resonance (SPR), although the method to determine KD is not particularly limited. Preferably, binding affinity is determined using (at least) SPR. The affinity may be calculated by the ratio of the dissociation rate constant (kd) and the association rate constant (ka), which may be determined for example by SPR.

[0043] As regards the anti-cTnT antibody, it is preferred that under identical experimental conditions the anti-cTnT antibody binds to an epitope within the cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 4 with a lower KD compared to (said anti-cTnT antibody when binding to) an epitope within the skTnT peptide sequence (comprised in the conserved skTnT peptide sequence(s)) as set forth in SEQ ID NO: 5 and / or 6.

[0044] Herein, the term “lower” may be understood as any value i) being smaller than a given reference value used for the respective comparison, ii) being significantly lower, e.g., as shown by a statistical test, and / or iii) deviating from a given reference value used for the respective comparison by at least, e.g., 2.5% or 5% or 7.5% or 10%. Accordingly, the term “higher” may be understood as any value i) being larger than a given reference value used for the respective comparison, ii) being significantly higher, e.g., as shown by a statistical test, and / or iii) deviating from a given reference value used for the respective comparison by at least, e.g., 2.5% or 5% or 7.5% or 10%. In the same line, herein the term “decreased” may refer to any value i) being smaller than a given reference value used for the respective comparison, ii) being significantly lower, e.g., as shown by a statistical test, and / or iii) deviating from a given reference value used for the respective comparison by at least, e.g., 2.5% or 5% or 7.5% or 10%. Accordingly, the terms “increased” and / or “elevated” may refer to any value i) being larger than a given reference value used for the respective comparison, ii) being significantly higher, e.g., as shown by a statistical test, and / or iii) deviating from a given reference value used for the respective comparison by at least, e.g., 2.5% or 5% or 7.5% or 10%.

[0045] Additionally or alternatively, the anti-skTnT antibody may described by defining its variable regions. Commonly, an antibody comprises a heavy chain variable region, comprising three CDRs, and a light chain variable region, comprising three CDRs. A “CDR” refers to a complementarity-determining region and may be understood as a hypervariable domain that may determine and / or influence the antibody’s specific binding.

[0046] For example, the anti-skTnT antibody may comprise a heavy chain variable region (VH) comprising CDR-H1, CDR-H2 and CDR-H3 and a light chain variable region (VL) comprising CDR-L1, CDR-L2 and CDR-L3 selected from the group consisting of CDR-H1 as depicted in SEQ ID NO: 7, CDR-H2 as depicted in SEQ ID NO: 8, CDR-H3 as depicted in SEQ ID NO: 9, CDR-L1 as depicted in SEQ ID NO: 10, CDR-L2 as depicted in SEQ ID NO: 11 and CDR-L3 as depicted in SEQ ID NO: 12. Respective sequences (relating, e.g., to clone A) are given in Table 1.

[0047] For example, the anti-skTnT antibody may comprise a heavy chain variable region (VH) comprising CDR-H1, CDR-H2 and CDR-H3 and a light chain variable region (VL) comprising CDR-L1, CDR-L2 and CDR-L3 selected from the group consisting of CDR-H1 as depicted in SEQ ID NO: 13, CDR-H2 as depicted in SEQ ID NO: 14, CDR-H3 as depicted in SEQ ID NO: 15, CDR- L1 as depicted in SEQ ID NO: 16, CDR-L2 as depicted in SEQ ID NO: 17 and CDR-L3 as depicted in SEQ ID NO: 18. Respective sequences (relating, e.g., to clone C) and are given in Table 1.

[0048] For example, the anti-skTnT antibody may comprise a heavy chain variable region (VH) comprising CDR-H1, CDR-H2 and CDR-H3 and a light chain variable region (VL) comprising CDR-L1, CDR-L2 and CDR-L3 selected from the group consisting of CDR-H1 as depicted in SEQ ID NO: 19, CDR-H2 as depicted in SEQ ID NO: 20, CDR-H3 as depicted in SEQ ID NO: 21, CDR- L1 as depicted in SEQ ID NO: 22, CDR-L2 as depicted in SEQ ID NO: 23 and CDR-L3 as depicted in SEQ ID NO: 24. Respective sequences (relating, e.g., to clone B) are given in Table 1.

[0049] Accordingly, the anti-skTnT antibody may comprise i) a VH region selected from the group consisting of those depicted in SEQ ID NO: 25, 26 and 27 and / or ii) a VL region selected from the group consisting of those depicted in SEQ ID NO: 28, 29 and 30. Preferably, the anti- skTnT antibody comprises i) a VH region as depicted in SEQ ID NO: 25 or 27 and / or ii) a VL region as depicted in SEQ ID NO: 28 or 30. Respective sequences are given in Table 1.

[0050] Preferably, the anti-skTnT antibody comprises a) a VH region as depicted in SEQ ID NO: 25 and a VL region as depicted in SEQ ID NO: 28, or b) a VH region as depicted in SEQ ID NO: 26 and a VL region as depicted in SEQ ID NO: 29, or c) a VH region as depicted in SEQ ID NO: 27 and a VL region as depicted in SEQ ID NO: 30. Preferably, the anti-skTnT antibody comprises a VH region as depicted in SEQ ID NO: 25 and a VL region as depicted in SEQ ID NO: 28, or a VH region as depicted in SEQ ID NO: 27 and a VL region as depicted in SEQ ID NO: 30. Said preferred antibody sequences may relate to clones A and B.

[0051] According to an embodiment, the anti-skTnT antibody may be capable of binding to an epitope within skTnT as set forth in SEQ ID No.2 (sskTnT) and / or as set forth in SEQ ID No. 3 (fskTnT) with a KD of 10-7M or less, or with a KD of 10-8M or less, or with a KD of 10-9M or less, or with a KD of 5x 10-9or less, or with a KD of 10-10or less.

[0052] As regards the antibodies, it is preferred that the anti-skTnT antibody is a monoclonal anti-skTnT antibody and / or that the anti-cTnT antibody is a monoclonal anti-cTnT antibody. Preferably, the anti-skTnT antibody is a monoclonal anti-skTnT antibody and the anti-cTnT antibody is a monoclonal anti-cTnT antibody. Additionally or alternatively, it is preferred that the anti-skTnT antibody is an anti-skTnT antibody that has been affinity maturated, humanized and / or stabilized, and / or that the anti-cTnT antibody is an anti-cTnT antibody that has been affinity maturated, humanized and / or stabilized. For example, the anti-skTnT antibody may be an anti- skTnT antibody that has been affinity maturated, humanized and / or stabilized, and the anti-cTnT antibody may be an anti-cTnT antibody that has been affinity maturated, humanized and / or stabilized. Preferably, the anti-skTnT antibody is a monoclonal anti-skTnT antibody that has been affinity maturated, humanized and / or stabilized, and the anti-cTnT antibody is a monoclonal anti- cTnT antibody that has been affinity maturated, humanized and / or stabilized.

[0053] Coming back to the method of the invention, said method is a method of determining the amount of cTnT in a sample, comprising the steps of a) contacting the sample with an anti- cTnT antibody and with an anti-skTnT antibody, wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT.

[0054] As regards the sample, it is preferred that the sample is a fluid sample and / or a sample selected from the group consisting of serum, plasma, whole blood, interstitial fluid and urine. Preferably, the sample is a serum or plasma sample. For example, the sample may be a bodily fluid sample. For example, the sample may be a serum sample that may have been collected using standard sampling tubes or tubes containing separating gel. For example, the sample may be a plasma sample to which K2-EDTA, K3-EDTA, Li-heparin and / or Na-heparin may have been added. For example, the sample may be a plasma sample that has been collected using a plasma tube containing separating gel.

[0055] For example, the sample (volume), used for determining the amount of cTnT therein, may comprise or may be between 15 µl and 50 µl, preferably between 20µl and 40 µl, more preferably between 25 µl and 35 µl, for example (about) 30µl.

[0056] Herein, the terms “about”, “approximately”, and / or “substantially” refer to a deviation of 20% or less, preferably of 15% or less, more preferably of 10% or less, even more preferably of 5% or less, most preferably of 1% or 0.5% or less. Thus, said terms relate to a value that iswithin a deviation of, e.g., maximal 10% or maximal 5% or maximal 1% or maximal 0.5% of a given value or range.

[0057] As regards the sample, the amount of cTnT therein is or is to be determined, it is preferred that the sample comprises or is suspected of comprising skTnT. Thus, in case of any indication of potential (e.g. suspected, present and / or elevated) skTnT levels which may interfere with a cTnT quantification assay, the scavenger antibody can be added to ensure precise cTnT quantification. This may especially be advantageous for subjects presenting with SMD symptoms, subjects having done physical exercise and / or subjects known or suspected of drug use. Moreover, this may be advantageous for care situations in which there may be no respective information available and / or diagnosis is required fast, as e.g. in case of AMI, to be able to initiate a respective treatment. Alternatively or additionally, the scavenger antibody may be added to a sample even in the absence of any indication concerning presence, suspected presence and / or potential presence of skTnT in the sample. This may be advantageous for example in case of (e.g. routine) cTnT quantification pipelines which may be set up sample-independently as in case of analytical laboratories, hospitals and / or external provider of analytical services to which samples may be sent for cTnT quantification.

[0058] Herein, a “subject” refers to a vertebrate, preferably a mammal, more preferably to a human. For example, a subject may refer to a healthy human, to a human at risk of developing a disease and / or an unfavorable condition, and / or to a human suffering from a disease and / or an unfavorable condition. For example, a subject may refer to a patient, wherein a patient may be a human being at risk of developing a disease, suspected of having a disease, resenting with symptoms of a disease and / or suffering from a disease.

[0059] The sample may comprise or being suspected of comprising skTnT in a concentration of at least 10 pg / mL, or of at least 15 pg / mL, or of at least 20 pg / mL, or of at least 25 pg / mL, or of at least 50 pg / mL, or of at least 100 pg / mL, or of at least 500 pg / mL, or of at least 1 ng / mL, or of at least 5 ng / mL, or of at least 10 ng / mL. Preferably, the sample comprises or is suspected of comprising skTnT in a concentration of at least 50 ng / mL, or of at least 100 ng / mL, or of at least 500 ng / mL, or of at least 1000 ng / mL. For example, the sample may comprise or being suspected of comprising skTnT in a concentration between 10 pg / mL and 10000 ng / mL, or between 50 pg / mL and 10000 ng / mL, or between 100 pg / mL and 10000 ng / mL. Preferably, the sample may comprise or being suspected of comprising skTnT in a concentration between 50 ng / mL and 10000 ng / mL or between 100 ng / mL and 10000 ng / mL or between 500 ng / mL and 10000 ng / mL or between 1000 ng / mL and 10000 ng / mL.

[0060] Preferably, the sample is or is suspected of being a sample obtained from a subject having skeletal muscle damage, wherein preferably the skeletal muscle damage is and / or has been induced by physical exercise, drug use and / or a skeletal muscle disease.

[0061] Skeletal muscle damage may be induced by physical exercise, wherein said physical exercise is to be understood in a broad sense. Skeletal muscle damage may occur in case of maximal eccentric contractions and marathons as indicated by reports focusing on cTnI. However, in view of these reports skeletal muscle damage that is associated with a release of skTnT into the blood, it can be hypothesized that the same effect, namely (e.g. elevated) skTnT levels in the blood, may be observed also in case of, e.g., professional athletes like soccer players, basketball players, dancers, body builders, boxers, swimmers, cyclists, triathletes and / or iron man participants to name a few illustrative examples. Moreover, though on a smaller scale compared to such professionals, (e.g. a presence or an elevation) of skTnT level in the blood may also be at least suspected, e.g., in case of subjects doing sports either without being sufficiently trained with regard to the sports workload done and / or subjects training for reaching a new level of fitness. The latter may also be relevant in the context of rehab and / or convalescence, for example after bedriddeness, surgery and / or resting posure (e.g. after a bone fracture) which may take several months and may thus be associated with a loss of fitness and / or muscles. In this context also long-covid effects may be relevant, for example, when a subject is trying to improve its fitness after having suffered from corona effects for weeks.

[0062] Skeletal muscle damage may be induced by drug use, wherein said drug use is to be understood in a broad sense. The term “drug use” encompasses both drug use as well as drug abuse. Accordingly, the term “drug” encompasses medications, medical treatments and / or medical therapies as well as (e.g. addictive) drugs that are not consumed in a medical use. A preferred drug example is a statin and / or a preferred (illustrative) treatment a statin treatment. Skeletal muscle damage may also be induced, e.g., in cancer patients treated with an immune checkpoint inhibitor (ICI). Accordingly, another preferred drug example is an ICI and / or a preferred (illustrative) treatment is a treatment with an ICI (preferably in case the subject is suffering from a cancer). Another preferred drug example is a vascular endothelial growth factor inhibitor (VEGFI) and / or a preferred (illustrative) treatment is a treatment with a VEGFI.

[0063] Skeletal muscle damage may be induced by a skeletal muscle disease (SDM). Herein, it is preferred that the SMD is selected from the group consisting of myopathy, myositis, muscular dystrophy, rhabdomyolysis, neuropathy, myasthenic syndrome and autosomal dominant (AD) with muscle symptoms. Preferably, the SDM is a myopathy and / or myositis. For example, the myopathy may be a skeletal myopathy and / or a non-inflammatory myopathy. For example, the myopathy may be a non-inflammatory myopathy, preferably selected from the group consisting of myotonic dystrophy, facioscapulohumeral muscular dystrophy, limb-girdle musculardystrophy, mitochondrial disease, and glycogen storage disease. For example, the myositis may be selected from the group consisting of dermatomyositis, polymyositis, sporadic inclusion body myositis, hereditary inclusion body myositis, immune-mediated necrotizing myositis, myositis with overlap with collagenous disease, myositis induced by physical exercise, myositis induced by drug use, preferably statin-induced myositis, ICI-induced myositis and / or VEGFI-induced myositis, and vasculitis.

[0064] As regards the method of the invention, step a) relates to contacting the sample with the anti-cTnT antibody and with the anti-skTnT antibody described herein above. Concerning said contacting, one of the following two approaches may be followed. The sample may be contacted with the anti-cTnT antibody concomitantly with the anti-skTnT antibody. This may be realized, e.g., by using an “updated” formulation of a cTnT quantification assay that comprises both the anti-skTnT antibody and the anti-cTnT antibody (or, e.g. in case of a sandwich assay the anti- cTnT antibodies, preferably at least the capture anti-cTnT antibody). In contrast, currently available cTnT assay formulations comprise only at least one anti-cTnT antibody but no anti- skTnT antibody. Thus, the scavenger antibody may be added to currently available cTnT assay formulation before packaging and the resulting updated formulation may be used in step a). Using an updated assay formulation comprising both the scavenger antibody and the at least one anti- cTnT antibody may advantageously maintain current working times and workloads as neither an additional incubation nor an additional pipetting step are required. Alternatively, the sample may be contacted with the anti-skTnT antibody before the sample, with the anti-skTnT antibody, is contacted with the anti-cTnT antibody. Thus, currently available cTnT quantification assay formulations comprising the at least one anti-cTnT antibody can be used as usual with the option to flexibly add a scavenger antibody when required, for example when a sample is suspected of comprising skTnT. Thus, maximal flexibility can be ensured that can also account for economic aspects if required. In case, the sample is to be pre-treated with the scavenger antibody, it is preferred that the sample is contacted with the anti-skTnT antibody (about) 0.5 min to 15 min before, more preferably (about) 5 to 20 min before the sample, with the anti-skTnT antibody, is contacted with the anti-cTnT antibody. Additionally or alternatively, it is preferred that the sample is contacted with the anti-skTnT antibody at least 5 min before, more preferably at least 9 min before the sample, with the anti-skTnT antibody, is contacted with the anti-cTnT antibody. Thus, such a pre-treatment with the scavenger antibody can be flexibly added before the work flow according to the instruction leaflet of the respective cTnT quantification assay is performed as usual. As a further alternative, it may also be envisioned to perform a pre-treatment with the scavenger antibody that can be understood as a purification step. In this case, the sample may be contacted with the scavenger antibody, wherein the scavenger antibody is immobilized on a surface and / or capable of being immobilized on a surface, thereby enabling immobilization of skTnT in the sample. The scavenger antibody may be (e.g. capable of being) immobilized on asurface by various means and methods, e.g. by labelling the scavenger antibody with a biotin label that can be immobilized on a streptavidin-coated surface like a streptavidin-coated microparticle surface or using a purification method e.g. based on centrifugation, precipitation, (e.g. column based) chromatography etc.. Thus, by removing skTnT from the sample, the sample can be cleared in view of potentially interfering skTnT in advance before performing a cTnT quantification using an anti-cTnT antibody using an available cTnT quantification assay in accordance with the instruction leaflet and thus, as usual. However, in case of this alternative, the sample is contacted with the anti-skTnT antibody, before, after purifying step as just described, the sample, without the anti-skTnT antibody, is contacted with the anti-cTnT antibody for cTnT quantification.

[0065] Concerning step b) of the method, relating to the determination of the amount of cTnT in the sample, reference is made to the respective cTnT quantification assay used. As an illustrative example, a possible way of determining the amount of cTnT in a sample will be described in view of the commercially available Elecsys® cTnT-hs assay. In brief, the (detector) anti-cTnT antibody used in step a) may be an anti-cTnT antibody labelled with a luminescence label. The sample may be contacted in step a) additionally with an immobilization antibody against cTnT (cTnT immobilization antibody), preferably whereby cTnT is immobilized on a surface. Thus, cTnT comprised in the sample may be immobilized in step a) by the cTnT immobilization antibody and sandwiched with the anti-cTnT antibody (as detection antibody). Preferably, the method may comprise a washing step between step a) and step b) to remove, e.g., anti-cTnT antibodies not immobilized via cTnT on the surface. In step b) the amount of cTnT in the sample may be determined using a signal obtained from the labelled anti-cTnT antibody. The presence of an anti- skTnT antibody provides binding of the anti-cTnT antibody to skTnT without affecting binding of the anti-cTnT antibody to cTnT. Moreover, it can be easily understood in this illustrative example of a sandwich assay for cTnT quantification that the basic principle of a scavenger antibody can be employed to the anti-cTnT antibody and / or the cTnT immobilization antibody. While a scavenger antibody designed to prevent binding of the anti-cTnT antibody to skTnT may allow both cTnT and skTnT to be immobilized, only immobilized cTnT can be bound by the (detection) anti-cTnT antibody and thus, give rise to a respective signal. When a scavenger antibody designed to prevent binding of the cTnT immobilization antibody to skTnT is used, only cTnT may be immobilized and give raise to a respective signal upon being bound by the (detection) anti- cTnT antibody. The latter may bind skTnT, but may be washed away due to its missing immobilization. Thus, the principle of preventing binding of an anti-cTnT antibody to a homologous skTnT peptide sequence using a scavenger anti-skTnT antibody can be realized for the (detection) anti-cTnT antibody, the cTnT immobilization antibody or both, while ensuring in all three cases precise cTnT quantification in the presence or suspected presence of skTnT in a sample. Following the same rational, the same applies in case of an cTnT quantification assay inwhich anti-cTnT antibody and cTnT immobilization antibody are exchanged in view of their respective labeling with a luminescence label and an immobilization label like a biotinylation, respectively. For example, in case of the Elecsys® cTnT-hs assay, the cTnT immobilization antibody may be the M11.7 antibody and the anti-cTnT antibody the M7 antibody as it is the case on the currently available array, or the cTnT immobilization antibody may be the M7 antibody and the anti-cTnT antibody the M11.7 antibody. Herein, it is preferred that (as in case of the currently available array Elecsys® cTnT-hs assay) the anti-cTnT antibody is the M11.7 (“capture”) antibody and that the scavenger antibody is preventing binding of the M11.7 antibody to skTnT.

[0066] Furthermore, the method may further comprise the step of c) comparing the determined amount of cTnT with a reference. Herein, said “reference” may be understood as encompassing both a single reference as well as more than one references. The reference may be a single value (for the amount), a range and / or a combination thereof (all of these options are to be understood as per reference in case of more than one reference). The reference may be a predetermined reference cTnT amount, for example a reference cTnT amount stored, e.g., in a (physical and / or electronic) database, a software, on a storage medium and / or electronically accessible. Preferably, the reference is a reference cTnT amount. This may be advantageous for interpreting the amount of cTnT determined in the sample.

[0067] For example, the reference may be a reference for a healthy condition and / or for cardiac muscle damage. This may be advantageous as it allows diagnosing a condition deviating from a healthy condition and / or cardiac muscle damage. For example, when the reference is a reference for a healthy condition, an increased amount of skTnT determined in the sample compared to the reference is indicative for skeletal muscle damage. Additionally or alternatively, the reference may be determined in a clinical study and / or represent a commonly accepted threshold. For example, a cTnT amount in a sample above 52 ng / L (e.g., as determined using the Elecsys® cTnT-hs (Gen5) assay) may be indicative for AMI. Additionally or alternatively, the reference may be a reference cTnT amount determined at an earlier point in time. This may be advantageous for investigating changes of cTnT over time and / or to monitor the amount of cTnT, e.g. in a subject over time. Accordingly, a difference in the amount of cTnT determined in the sample compared to the reference may be indicative for a change of cardiac muscle damage over time.

[0068] Thus, the method is preferably a method of detecting, diagnosing and / or monitoring a disease associated with cTnT, wherein the disease associated with cTnT is preferably cardiac muscle damage. Said cardiac muscle damage is preferably a cardiac muscle damage selected from the group consisting of Acute Myocardial Infarction (AMI), Acute Coronary Syndrome (ACS), Myocardial Injury after Non-Cardiac Surgery (MINS), Periprocedural Myocardial Infarction (PMI) and heart failure. Preferably, the cardiac muscle damage is AMI. Detection, diagnosis and / ormonitoring of a disease associated with cTnT, preferably cardiac muscle damage such as AMI, may be facilitated using the method according to the present invention as the presence of the scavenger antibody prevents potential interference of skTnT with the anti-cTnT antibody used for cTnT quantification. Thus, the scavenger antibody can not only ensure reliable, reproducible and high-sensitive cTnT quantification using currently available cTnT quantification assays. The scavenger antibody can also maintain or even improve diagnostic accuracy of a diagnosis such as AMI when said diagnosis is based on the cTnT amount determined in a sample. In case of no interference between the anti-cTnT antibody and skTnT and / or (substantially) no skTnT being present in the sample, the scavenger antibody is designed not to affect cTnT quantification. Contrarily, in case of a potential interference between the anti-cTnT antibody and skTnT and skTnT being present in the sample, false positive diagnostic results based on elevated cTnT measurements in the presence of skTnT in the sample can be avoided as the scavenger antibody blocks binding of the anti-cTnT antibody to skTnT. Thus, the diagnostic accuracy for a diagnosis of a disease associated with cTnT that is based on amounts of cTnT in a sample using an anti- cTnT antibody can be maintained or even improved. This may be especially advantageous in point of care situations.

[0069] The method of the invention, including the embodiments described herein above, may also be understood as a method of preventing skeletal Troponin T (skTnT) interference in determining the amount of cardiac Troponin T (cTnT), said method comprising the steps of a) contacting the sample with an antibody against cTnT (anti-cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT. As regards the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample and the method steps, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0070] Herein, the term “interference” refers to the effect of a substance present in the sample that alters the correct value of the result to be determined. It may also be understood that the correct value of the result to be determined is altered, e.g. due to a lack of specificity for example in case of an antibody based assay, method and / or test. Herein, the term “specificity” as e.g. used in a phrase like “specificity in determining the amount” preferably refers to antibodyspecificity and in particular to the ability of an antibody to discriminate between similar and / or dissimilar targets. For example, when in an antibody based assay, method and / or test the respective antibody is capable of binding to both a target, the amount of which is to be determined, as well as to at least one non-target, such a lack of specificity can give rise to an interference resulting in a determined amount of the target that differs from the (real) amount of said target present e.g. in the sample under study. In particular, the potential interference of skTnT in cTnT quantification using an anti-cTnT antibody gave rise to the present invention. In view of the hypothesis of cTnT quantification being impacted by the presence of skTnT in a sample, potentially leading to cTnT amounts being determined higher compared to amounts of cTnT that would have been determined in the absence of skTnT in said sample, the scavenger antibody approach was designed to prevent binding of the anti-cTnT antibody to skTnT in the presence of said scavenger and thus, enabling precise cTnT quantification in samples, especially in the suspected or actual presence of skTnT in said sample.

[0071] Accordingly, the method of the invention, including the embodiments described herein above, may also be understood as a method of maintaining or improving specificity in determining the amount of cardiac Troponin T (cTnT) in a sample, said method comprising the steps of a) contacting the sample with an antibody against cTnT (anti-cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT, wherein specificity in determining the amount of cTnT is maintained or improved compared to a method performed without said anti-skTnT antibody under identical experimental conditions. As regards the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample and the method steps, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0072] The method of the invention, including the embodiments described herein above, may also be understood as a method of maintaining or improving diagnostic accuracy and / or diagnostic specificity for a disease associated with cardiac Troponin T (cTnT) in a sample, said method comprising the steps of a) contacting the sample with an antibody against cTnT (anti- cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved betweencTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT, (optionally wherein the determined amount of cTnT compared to a reference is or is not indicative of a disease associated with cTnT,) and wherein diagnostic accuracy and / or diagnostic specificity is maintained or improved compared to a method performed without said anti-skTnT antibody under the under identical experimental conditions experimental conditions. As regards the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample and the method steps, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0073] Herein, the term “diagnostic accuracy” refers to the ability of a method, test and / or assay, preferably a diagnostic method and / or a diagnostic assay, to discriminate between a diseased condition and a healthy condition. This discriminative potential can be quantified by measures of diagnostic accuracy such as diagnostic sensitivity and diagnostic specificity. The diagnostic accuracy may be understood as the proportion of true results, either true positive or true negative, identified by a method and / or assay out of all results. Accordingly, the higher the diagnostic accuracy of a method and / or assay, the more reliable can its results are considered.

[0074] Herein, the term “diagnostic specificity” relates to the ability of a method and / or test, preferably a diagnostic method and / or test, to correctly identify samples of subjects not suffering from a disease like a disease associated with cTnT and / or cardiac muscle damage. Thus, the diagnostic specificity may refer to a true negative rate, which may also be understood as the proportion of true negatives correctly identified by said method and / or assay. Diagnostic specificity may thus be understood as a measure of diagnostic accuracy, and may be defined as a proportion of subjects not suffering from a disease and with negative test result in total of subjects not suffering from said disease (i.e. true negatives divided by the sum of true negatives and false positives). Thus, diagnostic specificity may reflect the probability of a negative test result in a subject not suffering from a disease.

[0075] Herein, the term “diagnostic sensitivity” (may be abbreviated as sensitivity) may relate to the ability of a method and / or test, preferably a diagnostic method and / or test, to correctly identify samples of subjects suffering from a disease like a disease associated with cTnT and / or cardiac muscle damage. Thus, the diagnostic sensitivity may refer to a true positive rate, which may also be understood as the proportion of true positives correctly identified by said method and / or assay. Diagnostic sensitivity may thus be understood as a measure of diagnostic accuracy,and may be defined as a proportion of subjects suffering from a disease and with positive test result in total of subjects suffering from said disease (i.e. true positives divided by the sum of true positives and false negatives). Thus, diagnostic sensitivity may reflect the probability of a positive test result in a subject suffering from a disease.

[0076] The present invention also relates to the use of an anti-skTnT antibody (as described herein above) for determining the amount of cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. Preferably, the use comprises the method of the present invention (as described herein above). As regards the anti-cTnT antibody, the anti- skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample and the method steps, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0077] The present invention also relates to the use of an antibody against skeletal Troponin T (anti-skTnT antibody) (as described herein above) for preventing skeletal Troponin T (skTnT) interference in determining the amount of cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. Preferably, the use comprises the method of the present invention (as described herein above). As regards the anti-cTnT antibody, the anti- skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample and the method steps, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0078] The present invention also relates to the use of an anti-skTnT antibody (as described herein above) for maintaining or improving specificity in determining the amount of cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capableof binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. Preferably, the specificity in determining the amount of cTnT in the sample is maintained or improved compared to the situation when the anti-skTnT antibody is not used with otherwise identical experimental conditions experimental conditions. Preferably, the use comprises the method of the present invention (as described herein above). As regards the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample and the method steps, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0079] The present invention also relates to the use of an anti-skTnT antibody (as described herein above) for maintaining or improving diagnostic accuracy and / or diagnostic specificity for a disease associated with cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. Preferably, the diagnostic accuracy and / or diagnostic specificity is / are maintained or improved compared to the situation when the anti-skTnT antibody is not used with otherwise identical experimental conditions. Preferably, the use comprises the method of the present invention (as described herein above). As regards the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample and the method steps, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0080] The present invention also relates to a composition comprising an antibody against skeletal Troponin T (anti-skTnT antibody) and an antibody against cardiac Troponin T (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. As regards the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, and the conserved skTnT peptide sequence, the same applies as it hasbeen described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above. The composition may be understood as an updated formulation of a cTnT quantification assay that comprises both the anti-skTnT antibody and the anti-cTnT antibody (or, e.g. in case of a sandwich assay the anti-cTnT antibodies, preferably at least the detection anti-cTnT antibody). Thus, the scavenger antibody may be added to a, e.g. currently available, cTnT assay formulation, preferably before packaging, and the resulting updated formulation could be used in step a) of the method of the present invention as described herein above in detail. Thus, the composition may be used in step a) of the method of the present invention. Accordingly, the sample may be contacted in step a) with the anti-cTnT antibody concomitantly with the anti- skTnT antibody. Contacting of the sample with such an updated formulation may be performed as described, e.g., in the leaflet of a respective cTnT quantification assay. Thus, using an updated assay formulation may advantageously maintain current working times and workloads compared to the respective current assay formulation as neither an additional incubation (time) nor an additional pipetting step is required.

[0081] The present invention also relates to a composite composition comprising a first composition and a second composition, wherein said first composition comprises an antibody against skeletal Troponin T (anti-skTnT antibody) and wherein said second composition comprises an antibody against cardiac Troponin T (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby (being capable of) preventing binding of the anti-cTnT antibody to skTnT. As regards the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, and the conserved skTnT peptide sequence, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above. The composite composition may be understood as a kit comprising the first composition including the anti-skTnT antibody for pre-treatment of a sample and the second composition including the anti-cTnT antibody for treatment of the sample, wherein the second composition preferably is a, e.g. currently available, cTnT assay formulation. The composite composition may be used in step a) of the method of the present invention as described herein above in detail. Thus, the sample would in this case be contacted in step a) with the first composition comprising the anti-skTnT antibody of the composite composition before the sample, with the anti-skTnT antibody, is contacted with the second composition comprising the anti-cTnTantibody of the composite composition. Contacting of the sample with the second formulation may be performed as described in the respective cTnT quantification assay leaflet.

[0082] The present invention also relates to the composition for use in diagnosing a disease associated with cardiac Troponin T (cTnT). The present invention also relates to the composite composition for use in diagnosing a disease associated with cardiac Troponin T (cTnT). Preferably, the diagnosing comprises the method of the present invention. As regards the composition, the composite composition, the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample, the method, and the disease associated with cTnT, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0083] The present invention also relates to the use of the composition or of the composite composition for determining the amount of cardiac Troponin T (cTnT) in a sample, wherein said use preferably comprises the method of the invention. As regards the composition, the composite composition, the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample, and the method, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0084] The present invention also relates to the use of the composition or of the composite composition for preventing skeletal Troponin T (skTnT) interference in determining the amount of cardiac Troponin T (cTnT) in a sample, wherein said use preferably comprises the method of the invention. As regards the composition, the composite composition, the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample, and the method, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0085] The present invention also relates to the use of the composition or of the composite composition for maintaining or improving specificity in determining the amount of cardiac Troponin T (cTnT) in a sample, wherein said use preferably comprises the method of the invention. Preferably, the specificity in determining the amount of cTnT in the sample is maintained or improved compared to the situation when the anti-skTnT antibody is not used with otherwise identical experimental conditions experimental conditions. As regards the composition, the composite composition, the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample, the method, and thedisease associated with cTnT, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0086] The present invention also relates to the use of the composition or of the composite composition for maintaining or improving diagnostic accuracy and / or diagnostic specificity for a disease associated with cardiac Troponin T (cTnT) in a sample, wherein said use preferably comprises the method of the invention. Preferably, the diagnostic accuracy and / or diagnostic specificity for a disease associated with cTnT is maintained or improved compared to the situation when the anti-skTnT antibody is not used with otherwise identical experimental conditions experimental conditions. As regards the composition, the composite composition, the anti-cTnT antibody, the anti-skTnT antibody, the conserved cTnT peptide sequence, the conserved skTnT peptide sequence, the sample, the method, and the disease associated with cTnT, the same applies as it has been described herein above in connection with the method of determining the amount of cTnT in a sample according to the invention. Moreover, also the respective other features can be as described herein above.

[0087] As used herein, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

[0088] As used herein, the term “and / or” includes the meaning of “and,” “or,” and “all or any other combination of the elements connected by said term.”

[0089] It is to be noted that in case of any definition given herein, the respective definition of a term, phrase, and / or abbreviation applies vice versa throughout the specification. Furthermore, all definition given herein are intended to encompass all grammatical forms.

[0090] The invention will be better understood with reference to the non-limiting examples and the drawings, in which:

[0091] Figure 1: Figure 1 shows results of a kinetic screening with exemplary kinetic signatures of antibody / TnT interactions for monoclonal Abs A (top), B (middle) and C (bottom). Shown is the binding to (A) sskTnT (B) fskTnT (C) cTNT with 150 nM TnT concentrations, Interactions with significant target binding are overlaid with a Langmuir 1:1 dissociation fitting model (grey).

[0092] Figure 2: Figure 2 shows results of a kinetic screening with respect to exemplary candidate antibodies obtained in the immunization campaign that were deselected in view of kineticsignatures of antibody / TnT interactions indicative of no binding, too slow complex formation velocities, fast dissociation or biphasic dissociation.

[0093] Figure 3: Figure 3 shows results with respect to kinetic signatures of antibody / TnT interactions for monoclonal Abs A, B and C (left to right) according to the present invention. Shown are series of fskTnT-concentrations, c = 3-240 nM, with duplicates for concentration 26.7 nM, wherein Figure 3 A) shows measured kinetic profiles (black) being overlaid with the Langmuir 1:1 binding Model, RI =0, Rmax global with allowed correction for mass transport limitation, depicted grey (right), and wherein Figure 3 B) shows measured kinetic profiles (grey) overlaid with Langmuir 1:1 binding Model, RI =0, Rmax global with fitting, here visualizing profiles, corrected for the MTL (black).

[0094] Figure 4: Figure 4 shows results with respect to kinetic signatures for monoclonal Abs A, B and C binding helical peptides at 37°C. Shown are the binding signatures (left) for peptide concentration-series, c = 1.2-300 nM, 1.2-100 nM or 1.2-33.3 nM, depicted in black and overlays (right) with a Langmuir 1:1 binding Model, Refractive Index (RI) set 0 and Rmaxglobal, depicted grey, wherein Figure 4A shows the kinetic signature for monoclonal Ab A binding to peptides TNNT3b (115-176) (SEQ ID No.38), TNNT3c (106-146) (SEQ ID No.39) and TNNT3d (106-186) (SEQ ID No.40), (top to bottom); wherein Figure 4B shows monoclonal Ab C binding to peptides TNNT3b (115-176) (SEQ ID No.38), TNNT3c (106-146) (SEQ ID No.39) and TNNT3d (106-186) (SEQ ID No 40) (top to bottom), and wherein Figure 4C shows monoclonal Ab B binding to peptides TNNT3b (115-176) (SEQ ID No.38), TNNT3c (106-146) (SEQ ID No. 39) and TNNT3d (106-186) (SEQ ID No.40), TNNT1b (40-132) (SEQ ID No.43) and TNNT1c (102-141) (SEQ ID No.44), (top to bottom). The interactions for monoclonal Abs C and B are corrected for the occurred mass transport limitation.

[0095] Additional objects, advantages, and features of the invention will become apparent to those skilled in the art upon examination of the following Examples and the attached Figures thereof, which are given for the purpose of illustration and by way of limitation. Thus, it should be understood that although the present invention is specifically described by exemplary embodiments and optional features, modification and variation of the herein described embodiments may be resorted and are considered to be within the scope of the present invention.

[0096] Each publication, patent, patent application or other document cited herein is hereby incorporated by reference in its entirety. EXAMPLES

[0097] Methods and materials are described herein for use in the present disclosure; other, suitable methods and materials known in the art can also be used. The materials, methods, and examples are illustrative and not intended to be limiting.

[0098] The inventors developed highly specific antibodies against skTnT that are capable of recognizing epitopes within skTnT, without showing cross-reactivity to the highly homologous (conserved) cTnT. The design of the antibody epitopes was based on the M11.7 anti-cTnT antibody used in cardiac Troponin T assays (Elecsys® cTnT-hs assay and POC test). The binding site of the M11.7 antibody in cTnT was aligned to fast and skeletal Troponin T sequences. Based on these alignments, the inventors designed various immunogens and screening peptides to target both fast and slow skTnT and to ensure no cross-reactivity to cTnT by counter screening with cTnT peptides. Due to the high homology (conservation) of cTnT, sskTnT and fskTnT proteins, antibodies were designed that are able to recognize differences of only one or two amino acids. The antibodies were found to be suitable scavenger antibodies for diagnostic immunoassays.

[0099] Antibody generation against human skeletal Troponin T

[0100] Rational: For generating specific antibodies against skTnT, New Zealand white rabbits were immunized with selected skTnT peptides and screened for skTnT peptide and protein binding capability. To rule out recognition of cTnT, counter screenings with cTnT peptides and recombinant cTnT were performed. Peptides for screening and immunization were generated in- house by peptide synthesis.

[0101] Peptides were synthesized by means of fluorenylmethyloxycarbonyl (Fmoc) solid phase peptide synthesis on a multiple peptide synthesizer, e.g. from Protein Technologies, Inc. For this, 4.0 equivalents of each amino acid derivative were used. Amino acid derivatives were dissolved in dimethylformamide containing 1 equivalent of 1-hydroxy-7-azabenzotriazol. Peptides were synthesized on Tentagel R resin. Coupling reactions were carried out for 5 minutes in dimethylformamide as a reaction medium with 4 equivalents HATU (1- [Bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate) and 8 equivalents of N,N-diisopropylethylamine relative to resin loading. The Fmoc group was cleaved in 8 minutes after each synthesis step using 25% piperidine in dimethyl formamide. Release of the peptide from the synthesis resin and the cleavage of the acid-labile protecting groups were achieved in 3 hours at room temperature with 9.5 ml trifluoroacetic acid, 0.25 ml triisopropylsilane, and 0.25 ml water. The reaction solution was subsequently mixed cooled diisopropyl ether to precipitate the peptide. The precipitate was filtered, washed again with diisopropyl ether, dissolved in a small amount of aqueous acetic acid and lyophilized. The crude material obtained was purified by preparative reversed phase chromatography (RP-HPLC) using a gradient of acetonitrile / water containing 0.1% trifluoroacetic acid. The identity of the purified material was checked by means of ion spray mass spectrometry.

[0102] As immunogens, human fast and slow skTnT peptides (slow skTnT: sskTnT / TNNT1, fast skTnT: fskTnT / TNNT3) were synthesized. Therefore, 3-(maleimido)propionic acid N- hydroxysuccinimide ester was added to a solution of keyhole limpet hemocyanin (KLH) in phosphate buffer (20 mM , pH 7.2). The reaction was incubated for 5 hours at room temperature and then dialyzed against phosphate buffer (0.1 M, pH 7.0). Cysteine containing peptide was dissolved in DMSO and added to a solution of maleimide-activated KLH containing 0.1 M ethylenediaminetetraacetic acid (EDTA). The solution was agitated for 5 hours at room temperature and then dialyzed against phosphate buffer (0.1 M, pH 7.0) to yield KLH-peptide conjugate. The resulting immunogen peptides had the sequences as set forth in SEQ ID NOs 5, 6, 32, 33, 35, and 36 with an additional “ßAla-Ahx-ßAla-Cys” (SEQ ID No. 61) at the respective C-terminus; all immunogens were coupled to KLH. For screening, biotinylated human fast and slow skTnT peptides were used with human cTnT (TNNT2) peptides for counter screening to rule out cross-reactivity to cTnT. The resulting screening peptides had the sequences as set forth in SEQ ID NOs 52, 53, 54, 55, 56, 57, 58, 59, and 60 with an additional “Biotin-PEG3” label at the respective N -terminus; peptides were used as biotin conjugates for ELISA and SPR screenings.

[0103] The immunization procedure resulted in various rabbit IgG clones reacting specifically with human skTnT, but not with cTnT (de-selection of cTnT binders with cTnT screening peptides). Specificity of these antibodies for skTnT peptides and the full-length protein was demonstrated by enzyme-linked immunosorbent assay (ELISA) screenings (not shown and SPR-based kinetic screening of the B cell supernatants. For the selection of highly specific skTnT binders, ELISA screenings with skTnT screening peptides and counterscreenings with cTnT screening peptides were performed. We deselected 6001 cTnT binding skTnT antibodies and could obtain 5011 skTnT specific antibodies without cTnT cross- reactivity. The experiments of the kinetic screening were conducted with recombinant human slow skeletal Troponin T (sskTnT), molecular mass 33 kDa, recombinant human fast skeletal Troponin TnT (fskTnT), molecular mass 31 kDa and recombinant human cardiac TnT (cTnT), molecular mass 35 kDa. Interactions were analyzed using the system buffer HBS-ET+ pH 7.4, 10 mM HEPES, 150 mM NaCl, 3 mM EDTA, 0.05% (w / v) Tween 20, pH 7.4 The system buffer was supplemented with 1 mg / mL Carboxymethyldextran (Fluka) and was used as sample buffer.

[0104] Kinetic screening was performed at 37 °C on GE Healthcare BIAcore™ 8K +, 8K and B4000 instruments. A Biacore CM5 Series S was functionalized at 25°C with a rabbit species- specific antibody capture system. A polyclonal goat anti-rabbit IgG Fc capture antibody GARbFcγ (111-005-046, Jackson ImmunoResearch) was amine coupled using EDC / NHS chemistry according to the manufacturer’s instructions. Finally, ligand densities between 10000 RU-15000 RU were obtained. Rabbit antibody (IgG 150 kDa) solutions were diluted in sample buffer and were injected at 5 µl / min or 10 µL / min for 2 minutes. The antibody Capture Level (CL) inresonance units (RU) was monitored.150 nM analyte sskTnT, cTnT or fskTnT was injected to the precaptured antibodies. The analyte association phases were monitored for 5 minutes. The antibody / TnT protein complex dissociation phases were monitored for 5 minutes. After each measurement cycle, the capture systems were regenerated by subsequent injections of 10 mM Glycine buffers pH 2.0 and pH 2.25 at 20 µL / min for 60 seconds. Kinetic signatures were monitored by the BIAcore™ 8K Control-SW V3.0.11.15423 and evaluated by the BIAcore™ Insight Evaluation SW V3.0.11.15423, respectively B4000 Control SW V1.1 and Evaluation SW V1.1. Kinetic data was interpreted by report point evaluations. Two report points, the recorded response signal shortly before the end of the protein analyte injection, analyte Binding Late (BL), and the signal shortly before the end of the dissociation phase, Stability Late (SL), were used to compare the antibody / antigen complex stabilities. The dissociation rate constant kd (s-1) was calculated according to a Langmuir model and the antibody / antigen complex half-life was calculated in minutes according to the formula t / 2 diss= ln(2) / (kd*60). The Molar Ratio, the binding stoichiometry was calculated by the formula MR = B(antigen)* MW(antibody) / (MW(antigen)* CL (antibody)). In total, 1095 antibodies from culture supernatants were analyzed. Candidates were identified with specific binding for sskTnT or fskTnT, or binding both, sskTnT and fskTnT and no detectable binding to cTnT were identified. Further, the obtained sensorgrams of the identified candidates were analyzed by visual inspection for fastest complex formation into Ab-equilibrium. The antibodies majority was deselected due to slow complex formation or artefact binding, see Fig. 2 for selected examples of kinetic profiles of deselected antibodies. Finally, 75 antibodies were identified with suitable kinetic properties meeting the criteria for the Elecsys®-platform. The kinetic rate constant ka(M-1s-1) was determined using a Langmuir 1:1 fitting model for the 75 antibodies. As the kinetic rate constants base on a single concentration 150 nM and a 5 minutes long monitored dissociation, the rate constants and resulting affinities represent apparent values. 75 antibodies have been selected with different specificity pattern (specificity for only fskTnT, specificity for only sskTnT, or specificity for both, sskTnT and fskTnT) in combination with superior kinetic properties, i.e. either with fastest complex formation, the highest affinities based on the single-concentration, and the highest complex half-life times.

[0105] Thus, clones A, B and C were identified as potential scavenger antibodies with high specificity for skTnT and suitable kinetic properties, see Figure 1.

[0106] Furthermore, the clones were characterized for the binding of fskTnT protein to determine the kinetic rate constants kaand kdand the resulting affinity KD. As described under section

[0102] for the kinetic screening, a multi cycle kinetic was performed by injecting a series of fskTnT concentrations, c = 3-240 nM with duplicates for concentration 26.7 nM, instead of a single concentration. The dissociation was monitored for 10 minutes. The obtained kinetic signatures are shown in Fig. 3 and obtained the binding parameters are summarized in table 2.

[0107] Table 2: mAb M-1s-1M-1s-1s-1s-1min M M RU Binding parameters for mAbs A, B, and C binding fast skTnT at 37°C. SE - Standard error of mean of the SPR-fit in comparison to the measured data points. Stated values are corrected for the occurred mass transport limitation via the Scrubber SW Version 2.0c using a two-compartment model.

[0108] Additionally, the monoclonal Abs (MAbs) A, B and C were analyzed for the binding to a selection of 9 helical peptides: TNNT3a (38-76) (SEQ ID No. 37), TNNT3b (115-176) (SEQ ID No.38), TNNT3c (106-146) (SEQ ID No.39), TNNT3d (106-186) (SEQ ID No.40), TNNT3e (148- 186) (SEQ ID No. 41), TNNT1a (31-70) (SEQ ID No. 42), TNNT1b (40-132) (SEQ ID No. 43), TNNT1c (102-141) (SEQ ID No.44), and TNNT1d (148-184) (SEQ ID No.45). All peptides were analyzed with concentrations c = 1.2-300 nM, 1.2-100 nM or 1.2-33.3 nM,, dissociation was monitored for 20 minutes. MAbs A and B show specific binding to 3 of the 5 analyzed helical TNNT3-peptides TNNT3b (115-176) (SEQ ID No. 38), TNNT3c (106-146) (SEQ ID No. 39) and TNNT3d (106-186) (SEQ ID No. 40). No detectable binding occurred for TNNT3-peptides TNNT3a (38-76) (SEQ ID No. 37) and TNNT3e (148-186) (SEQ ID No. 41) and for all TNNT1- peptides (TNNT1a-d)(SEQ ID No. 42, 43, 44 and 45). These data are in line with the results of the SPR-based kinetic screening analyzing the Ab-binding to skTnT proteins. The binding signatures for A and C differ from each other: mAb C shows a faster association and faster dissociation than mAb A, when binding to TNNT3b (115-176) (SEQ ID No.38) and TNNT3c (106- 146) (SEQ ID No. 39), see Fig.4 and Table 3.

[0109] Table 3: Clone M-1s-1M-1s-1s-1s-1min M M RUBinding parameters for mAbs A, B and C binding helical peptides at 37°C. SE - Standard error of mean of the SPR-fit in comparison to the measured data points. The obtained SPR-data are fitted with the Langmuir 1:1 binding model, RI set to zero and Rmax global. Stated values of mabs C and B are corrected for the occurred mass transport limitation via the Scrubber SW Version 2.0c using a two-compartment model.

[0110] Thus, the data indicated that the scavenger antibody clones A and B, which detected both fast and slow skeletal TnT, were excellent tools to reduce the cross reactivity of the cTnT antibodies to skTnT.

[0111] Assessment of cross-reactivity of cTnT and skTnT

[0112] Rational: In case of the Elecsys® cTnT-hs assay, cTnT detection using the electro- chemiluminescence immunoassay may be affected by cross-reaction between cTnT and skTnT when quantifying cTnT in the presence of skTnT. The assay employs two monoclonal antibodies directed against human cTnT. The antibodies recognize two epitopes (amino acid position 125- 131 of SEQ ID No .1 and 136-147 of SEQ ID No.1) located in the central part of the cTnT protein, which consists of in total 288 amino acids.

[0113] Sequence alignments of skTnT and cTnT

[0114] Sequence alignments of human skTnT and human cTnT revealed stretches of (near) perfect sequence identity indicative for conserved sequence regions. More specifically, comparison of amino acid sequences for cTnT as well as different slow-twich (s) and fast-twitch (f) skTnT sequences was used to determine the level of amino acid conservation across theinvestigated sequences. Binding regions of the antibodies employed in the Elecsys® cTnT-hs assay exhibited some level of sequence identity between skTnT and cTnT that may affect the assay´s analytical specificity of the cTnT quantification in the presence of skTnT in a sample under study. An existing though statistically not significant cross-reaction of 0.066% between cTnT and skTnT is also reported in the manufacturer´s leaflet in case of concentrations of about 18 ng / L cTnT and 500 ng / mL skTnT.

[0115] It will be readily apparent to a person skilled in the art that varying substitutions and modifications may be made to the invention disclosed herein without departing from the scope and spirit of the invention.

[0116] All patents, patent applications and publications are herein incorporated by reference to the same extent as if each individual publication was specifically and individually indicated to be incorporated by reference.

[0117] The inventions illustratively described herein may suitably be practiced in the absence of any element or elements, limitation or limitations, not specifically disclosed herein. Thus, for example, the terms "comprising", "including", "containing", etc. shall be read expansively and without limitation. Additionally, the terms and expressions employed herein have been used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. Thus, it should be understood that although the present invention has been specifically disclosed by preferred embodiments and optional features, modification and variation of the inventions embodied therein herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention. The invention has been described broadly and generically herein. Each of the narrower species and subgeneric groupings falling within the generic disclosure also form part of the invention. This includes the generic description of the invention with a proviso or negative limitation removing any subject matter from the genus, regardless of whether or not the excised material is specifically recited herein. In addition, where features or aspects of the invention are described in terms of Markush groups, those skilled in the art will recognize that the invention is also thereby described in terms of any individual member or subgroup of members of the Markush group. Further embodiments of the invention will become apparent from the following claims.

[0118] Equivalents: Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims.

[0119] The invention is further characterized by the following items: 1. An antibody against cardiac Troponin T (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skeletal Troponin T (skTnT) (conserved cTnT peptide sequence). 2. An antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-skTnT antibody is not capable of binding to a cardiac Troponin T (cTnT) peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby (being capable of) preventing binding of the anti-cTnT antibody to skTnT. 3. The anti-cTnT antibody of item 1 or the anti-skTnT antibody of item 2, wherein cTnT has the sequence set forth in SEQ ID NO: 1. 4. The anti-cTnT antibody of item 1 or 3 or the anti-skTnT antibody of item 2 or 3, wherein the conserved cTnT peptide sequence consists of amino acids 74 to 298 of SEQ ID NO: 1. 5. The anti-cTnT antibody of any one of items 1, 3 and 4 or the anti-skTnT antibody of any one of items 2 to 4, wherein the conserved cTnT peptide sequence comprises a cTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 4. 6. The anti-cTnT antibody of any one of items 1 and 3 to 5 or the anti-skTnT antibody of any one of items 2 to 5, wherein skTnT has the sequence set forth in SEQ ID NO: 2 and / or 3. 7. The anti-cTnT antibody of any one of items 1 and 3 to 6 or the anti-skTnT antibody of any one of items 2 to 6, wherein the conserved skTnT peptide sequence consist of i) amino acids 40 to 278 of SEQ ID NO: 2 (slow skTnT), and / or ii) amino acids 44 to 269 of SEQ ID NO: 3 (fast skTnT). 8. The anti-cTnT antibody of any one of items 1 and 3 to 7 or the anti-skTnT antibody of any one of items 2 to 7, wherein the conserved skTnT peptide sequence comprises i) a slow skTnT (sskTnT) peptide sequence consisting of the sequence set forth in SEQ ID NO: 5, and / or ii) a fast skTnT (fskTnT) peptide sequence consisting of the sequence set forth in SEQ ID NO: 6.The anti-skTnT antibody of any one of items 2 to 8, wherein the anti-skTnT antibody is not capable of binding to the conserved cTnT peptide sequence consisting of amino acids 74 to 298 of SEQ ID NO: 1. The anti-skTnT antibody of any one of items 2 to 9, wherein the anti-skTnT antibody is not capable of binding to the cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) consisting of the sequence set forth in SEQ ID NO: 4. The anti-skTnT antibody of any one of items 2 to 10, wherein the anti-skTnT antibody is not capable of binding to cTnT. The anti-skTnT antibody of any one of items 2 to 11, wherein the anti-skTnT antibody is capable of binding to i) the conserved skTnT peptide sequence consisting of amino acids 40 to 278 of SEQ ID NO: 2 (slow skTnT), and / or ii) the conserved skTnT peptide sequence consisting of amino acids 44 to 269 of SEQ ID NO: 3 (fast skTnT). The anti-skTnT antibody of any one of items 2 to 12, wherein the anti-skTnT antibody is capable of binding to i) an epitope within the sskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 5, and / or ii) an epitope within the fskTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 6. The anti-skTnT antibody of any one of items 2 to 13, wherein the anti-skTnT antibody is capable of binding to an epitope within sskTnT, wherein said sskTnT epitope comprises one or more amino acid positions of sskTnT, having the sequence set forth in SEQ ID NO: 2, selected from the group consisting of 118, 120, 122 and 132, and wherein at said one or more positions the amino acid is not N 118, R 120, K 122, and / or R 132. The anti-skTnT antibody of any one of items 2 to 14, wherein the anti-skTnT antibody is capable of binding to an epitope within fskTnT, wherein said fskTnT epitope comprises one or more amino acid positions of fskTnT, having the sequence set forth in SEQ ID NO: 3, selected from the group consisting of 122, 124, 126 and 136, and wherein at said one or more positions the amino acid is not N 122, R 124, K 126, and / or R 136.The anti-skTnT antibody of any one of items 2 to 15, wherein the anti-skTnT antibody is capable of binding to an epitope within sskTnT, wherein said sskTnT epitope comprises one or more amino acid positions of sskTnT, having the sequence set forth in SEQ ID NO: 2, selected from the group consisting of 118, 120, 122 and 132, and wherein said sskTnT epitope comprises at said one or more positions the amino acid(s) T 118, K 120, R 122 and K 132. The anti-skTnT antibody of any one of items 2 to 16, wherein the anti-skTnT antibody is capable of binding to an epitope within fskTnT, wherein said fskTnT epitope comprises one or more amino acid positions of fskTnT, having the sequence set forth in SEQ ID NO: 3, selected from the group consisting of 122, 124, 126 and 136, and wherein said fskTnT epitope comprises at said one or more positions the amino acid(s) A 122, K 124, R 126 and K 136. The anti-skTnT antibody of any one of items 2 to 17, wherein the anti-skTnT antibody comprises a heavy chain variable region (VH) comprising CDR-H1, CDR-H2 and CDR-H3 and a light chain variable region (VL) comprising CDR-L1, CDR-L2 and CDR-L3 selected from the group consisting of: a) CDR-H1 as depicted in SEQ ID NO: 7, CDR-H2 as depicted in SEQ ID NO: 8, CDR- H3 as depicted in SEQ ID NO: 9, CDR-L1 as depicted in SEQ ID NO: 10, CDR-L2 as depicted in SEQ ID NO: 11 and CDR-L3 as depicted in SEQ ID NO: 12; or b) CDR-H1 as depicted in SEQ ID NO: 13, CDR-H2 as depicted in SEQ ID NO: 14, CDR- H3 as depicted in SEQ ID NO: 15, CDR-L1 as depicted in SEQ ID NO: 16, CDR-L2 as depicted in SEQ ID NO: 17 and CDR-L3 as depicted in SEQ ID NO: 18; or c) CDR-H1 as depicted in SEQ ID NO: 19, CDR-H2 as depicted in SEQ ID NO: 20, CDR- H3 as depicted in SEQ ID NO: 21, CDR-L1 as depicted in SEQ ID NO: 22, CDR-L2 as depicted in SEQ ID NO: 23 and CDR-L3 as depicted in SEQ ID NO: 24. The anti-skTnT antibody of any one of items 2 to 18, wherein the anti-skTnT antibody comprises - a VH region selected from the group consisting of those depicted in SEQ ID NO: 25, 26 and 27 and / or - a VL region selected from the group consisting of those depicted in SEQ ID NO: 28, 29 and 30. The anti-skTnT antibody of any one of items 2 to 19, wherein the anti-skTnT antibody comprisesa) a VH region as depicted in SEQ ID NO: 25 and a VL region as depicted in SEQ ID NO: 28, or b) a VH region as depicted in SEQ ID NO: 26 and a VL region as depicted in SEQ ID NO: 29, or c) a VH region as depicted in SEQ ID NO: 27 and a VL region as depicted in SEQ ID NO: 30. The anti-skTnT antibody of any one of items 2 to 20, wherein the anti-skTnT antibody is a monoclonal anti-skTnT antibody. The anti-skTnT antibody of any one of items 2 to 21, wherein the anti-skTnT antibody is an anti-skTnT antibody that has been affinity maturated, humanized and / or stabilized. e anti-skTnT antibody of any one of items 2-22, wherein the anti-skTnT antibody is capable of binding to an epitope within skTnT as set forth in SEQ ID No.2 (sskTnT) and / or as set forth in SEQ ID No.3 (fskTnT) with a KD of 10-7M or less, or with a KD of 10-8M or less, or with a KD of 10-9M or less, or with a KD of 5x 10-9or less, or with a KD of 10-10or less. The anti-cTnT antibody of any one of items 1 and 3 to 8, wherein the anti-cTnT antibody is capable of binding to the conserved cTnT peptide sequence consisting of amino acids 74 to 298 of SEQ ID NO: 1. The anti-cTnT antibody of any one of items 1, 3 to 8 and 24, wherein the anti-cTnT antibody is capable of binding to an epitope within the cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 4. The anti-cTnT antibody of any one of items 1, 3 to 8, 24 and 25, wherein the anti-cTnT antibody is capable of binding to an epitope within cTnT, wherein said cTnT epitope comprises one or more amino acid positions of cTnT, having the sequence set forth in SEQ ID NO: 1, selected from the group consisting of 152, 154, 156 and 166, and wherein at said one or more positions the amino acid is N 152, R 154, K 156, and / or R 166. The anti-cTnT antibody of any one of items 1, 3 to 8, and 24 to 25, wherein under identical experimental conditions the anti-cTnT antibody binds to an epitope within the cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 4 with a lower KD compared to (said anti-cTnT antibody when binding to) an epitope withinthe skTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 5 and / or 6. The anti-cTnT antibody of any one of items 1, 3 to 8, and 24 to 26, wherein the anti-cTnT antibody is a monoclonal anti-cTnT antibody. The anti-cTnT antibody of any one of items 1, 3 to 8, and 24 to 27, wherein the anti-cTnT antibody is an anti-cTnT antibody that has been affinity maturated, humanized and / or stabilized. A method of determining the amount of cardiac Troponin T (cTnT) in a sample, said method comprising the steps of a) contacting the sample with an antibody against cTnT (anti-cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT. A method of preventing skeletal Troponin T (skTnT) interference in determining the amount of cardiac Troponin T (cTnT), said method comprising the steps of a) contacting the sample with an antibody against cTnT (anti-cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT.A method of maintaining or improving specificity in determining the amount of cardiac Troponin T (cTnT) in a sample, said method comprising the steps of a) contacting the sample with an antibody against cTnT (anti-cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT, wherein specificity in determining the amount of cTnT is maintained or improved compared to a method performed without said anti-skTnT antibody under identical experimental conditions. A method of maintaining or improving diagnostic accuracy and / or diagnostic specificity for a disease associated with cardiac Troponin T (cTnT) in a sample, the steps of a) contacting the sample with an antibody against cTnT (anti-cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT, optionally wherein the determined amount of cTnT compared to a reference is or is not indicative of a disease associated with cTnT, and wherein diagnostic accuracy and / or diagnostic specificity is maintained or improved compared to a method performed without said anti-skTnT antibody under the under identical experimental conditions experimental conditions.The method of any one of items 39 to 33, wherein the anti-cTnT antibody is the anti-cTnT antibody of any one of items 1, 3 to 8, and 24 to 28. The method of any one of items 30 to 34, wherein the anti-skTnT antibody is the anti-skTnT antibody of any one of items 2 to 23. The method of any one of items 30 to 34, wherein binding of the anti-cTnT antibody to skTnT is prevented by steric inhibition when the anti-skTnT antibody is bound to the conserved skTnT peptide sequence. The method of any one of items 30 to 35, wherein the conserved skTnT peptide sequence is homologous to the conserved (e.g. conserved in the) cTnT peptide sequence. The method of any one of items 29 to 36, wherein the anti-skTnT antibody is capable of binding to an epitope within the conserved skTnT peptide sequence (skTnT epitope). The method of item 38, wherein the skTnT epitope shares at least 75% sequence identity to a homologous (e.g. the conserved) peptide sequence in cTnT. The method of item 38 or 39, wherein the anti-cTnT antibody is capable of binding to an epitope within the conserved cTnT peptide sequence (cTnT epitope) and wherein the skTnT epitope comprises and / or is at least partially overlapping with a peptide sequence within skTnT that is homologous to (e.g. conserved in) the cTnT epitope. The method of any one of items 30 to 40, wherein the anti-cTnT antibody is not capable of binding to an epitope within the skTnT peptide sequence (comprised in the conserved skTnT peptide sequence) as set forth in SEQ ID NO: 5 and / or SEQ ID NO: 6 in the presence of the anti-skTnT antibody. The method of any one of items 30 to 41, wherein the anti-skTnT antibody is present i) in a concentration of at least 0.10 mg / mL and / or ii) in a concentration between 0.10 mg / mL and 30 mg / mL or in a concentration between 0.10 mg / mL and 20 mg / mL. The method of any one of items 30 to 42, wherein in step a) the sample is contacted with the anti-cTnT antibody concomitantly with the anti-skTnT antibody.The method of any one of items 30 to 42, wherein in step a) the sample is contacted with the anti-skTnT antibody before the sample, with the anti-skTnT antibody, is contacted with the anti-cTnT antibody, preferably 0.5 min to 15 min before, more preferably 5 to 20 min before and / or preferably at least 5 min before, more preferably at least 9 min before. The method of any one of items 30 to 44, further comprising the step of c) comparing the determined amount of cTnT with a reference. The method of item 45, wherein an increased amount of skTnT determined in the sample compared to the reference is indicative for a skeletal muscle damage. The method of item 45, wherein the reference is a reference cTnT amount determined at an earlier point in time. The method of item 47, wherein a difference in the amount of cTnT determined in the sample compared to the reference is indicative for a change of cardiac muscle damage over time. The method of any one of items 30 to 48, wherein the method is a method of detecting, diagnosing and / or monitoring a disease associated with cTnT. The method of item 49, wherein the disease associated with cTnT is cardiac muscle damage. The method of item 50, wherein the cardiac muscle damage is a cardiac muscle damage selected from the group consisting of Acute Myocardial Infarction (AMI), Acute Coronary Syndrome (ACS), Myocardial Injury after Non-Cardiac Surgery (MINS), Periprocedural Myocardial Infarction (PMI) and heart failure. The method of item 50 or 51, wherein the cardiac muscle damage is AMI. The method of any one of items 30 to 52, wherein the sample comprises or is suspected of comprising skTnT. The method of item 53, wherein the sample comprises or is suspected of comprising skTnT in a concentration of at least 50 ng / mL, preferably of 100 ng / mL or of at least 500 ng / mL or of at least 1000 ng / mL.The method of any one of items 30 to 54, wherein the sample is a fluid sample and / or a sample selected from the group consisting of serum, plasma, whole blood, interstitial fluid and urine. The method of item 55, wherein the sample is a serum or plasma sample. The method of any one of items 30 to 56, wherein the sample is or is suspected of being a sample obtained from a subject having skeletal muscle damage. The method of item 57, wherein the skeletal muscle damage is and / or has been induced by physical exercise, drug use and / or a skeletal muscle disease (SDM). The method of item 58, wherein SMD is selected from the group consisting of myopathy, myositis, muscular dystrophy, rhabdomyolysis, neuropathy, myasthenic syndrome and autosomal dominant (AD) with muscle symptoms. The method of item 58 or 59, wherein SMD is a myopathy and / or myositis. The method of item 60, wherein the myopathy is a non-inflammatory myopathy, preferably selected from the group consisting of myotonic dystrophy, facioscapulohumeral muscular dystrophy, limb-girdle muscular dystrophy, mitochondrial disease, and glycogen storage disease. The method of item 60, wherein the myositis is selected from the group consisting of dermatomyositis, polymyositis, sporadic inclusion body myositis, hereditary inclusion body myositis, immune-mediated necrotizing myositis, myositis with overlap with collagenous disease, myositis induced by physical exercise, myositis induced by drug use, preferably statin-induced myositis, ICI-induced myositis and / or VEGFI-induced myositis, and vasculitis. Use of an antibody against skeletal Troponin T (anti-skTnT antibody) for determining the amount of cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, andwherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. Use of an antibody against skeletal Troponin T (anti-skTnT antibody) for preventing skeletal Troponin T (skTnT) interference in determining the amount of cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. Use of an antibody against skeletal Troponin T (anti-skTnT antibody) for maintaining or improving specificity in determining the amount of cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. Use of an antibody against skeletal Troponin T (anti-skTnT antibody) for maintaining or improving diagnostic accuracy and / or diagnostic specificity for a disease associated with cardiac Troponin T (cTnT) using an antibody against cTnT (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT.The use of any one of items 63 to 66, wherein the anti-cTnT antibody is the anti-cTnT antibody of any one of items 1, 3 to 8, and 24 to 28. The use of any one of items 63 to 66, wherein the anti-skTnT antibody is the anti-skTnT antibody of any one of items 2 to 23. The use of any one of items 63 to 68, wherein said use comprises the method of any one of items 30 to 62. A composition comprising an antibody against skeletal Troponin T (anti-skTnT antibody) and an antibody against cardiac Troponin T (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT. A composite composition comprising a first composition and a second composition, wherein said first composition comprises an antibody against skeletal Troponin T (anti- skTnT antibody) and wherein said second composition comprises an antibody against cardiac Troponin T (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby (being capable of) preventing binding of the anti-cTnT antibody to skTnT. The composition of item 70 or the composite composition of item 71, wherein the anti-cTnT antibody is the anti-cTnT antibody of any one of items 1, 3 to 8, and 24 to 29. The composition of item 70 or 72 or the composite composition of item 71 or 72, wherein the anti-skTnT antibody is the anti-skTnT antibody of any one of items 2 to 23.The composition of item 70, 72 or 73 or the composite composition of any one of items 71 to 73 for use in diagnosing a disease associated with cardiac Troponin T (cTnT). The composition for use of item 74 or the composite composition for use of item 74, wherein said diagnosing comprises the method of any one of items 30 to 62. Use of the composition of item 70, 72 or 73 or the composite composition of any one of items 71 to 73 for determining the amount of cardiac Troponin T (cTnT) in a sample. Use of the composition of item 70, 72 or 73 or the composite composition of any one of items 71 to 73 for preventing skeletal Troponin T (skTnT) interference in determining the amount of cardiac Troponin T (cTnT) in a sample. Use of the composition of item 70, 72 or 73 or the composite composition of any one of items 71 to 73 for maintaining or improving specificity in determining the amount of cardiac Troponin T (cTnT) in a sample. Use of the composition of item 70, 72 or 73 or the composite composition of any one of items 71 to 73 for maintaining or improving diagnostic accuracy and / or diagnostic specificity for a disease associated with cardiac Troponin T (cTnT). The use of any one of items 76 to 79, wherein said use comprises the method of any one of items 30 to 62.

Claims

CLAIMS 1. A method of determining the amount of cardiac Troponin T (cTnT) in a sample, said method comprising the steps of a) contacting the sample with an antibody against cTnT (anti-cTnT antibody) and with an antibody against skeletal Troponin T (anti-skTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, and b) determining the amount of cTnT.

2. The method of claim 1, wherein - the conserved cTnT peptide sequence consists of amino acids 74 to 298 of SEQ ID NO: 1, preferably wherein said conserved cTnT peptide sequence comprises a cTnT peptide sequence consisting of the sequence set forth in SEQ ID NO: 4, and / or - the anti-cTnT antibody is capable of binding to an epitope within cTnT, wherein said cTnT epitope comprises one or more amino acid positions of cTnT, having the sequence set forth in SEQ ID NO: 1, selected from the group consisting of 152, 154, 156 and 166, and wherein at said one or more positions the amino acid is N 152, R 154, K 156, and / or R 166.

3. The method of claim 1 or 2, wherein - the conserved skTnT peptide sequence consist of amino acids 40 to 278 of SEQ ID NO: 2 (slow skTnT), preferably wherein said conserved skTnT peptide sequence comprises a slow skTnT (sskTnT) peptide sequence consisting of the sequence set forth in SEQ ID NO: 5, and / or - the conserved skTnT peptide sequence consist of amino acids 44 to 269 of SEQ ID NO: 3 (fast skTnT), preferably wherein said conserved skTnT peptide sequence comprises a fast skTnT (fskTnT) peptide sequence consisting of the sequence set forth in SEQ ID NO:

6.

4. The method of any one of the preceding claims, wherein- the anti-skTnT antibody is capable of binding to an epitope within sskTnT, wherein said sskTnT epitope comprises one or more amino acid positions of sskTnT, having the sequence set forth in SEQ ID NO: 2, selected from the group consisting of 118, 120, 122 and 132, and wherein at said one or more positions the amino acid is not N 118, R 120, K 122, and / or R 132, preferably wherein said sskTnT epitope comprises at said one or more positions the amino acid(s) T 118, K 120, R 122 and K 132, and / or - the anti-skTnT antibody is capable of binding to an epitope within fskTnT, wherein said fskTnT epitope comprises one or more amino acid positions of fskTnT, having the sequence set forth in SEQ ID NO: 3, selected from the group consisting of 122, 124, 126 and 136, and wherein at said one or more positions the amino acid is not N 122, R 124, K 126, and / or R 136, preferably wherein said fskTnT epitope comprises at said one or more positions the amino acid(s) A 122, K 124, R 126 and K 136.

5. The method of any one of the proceeding claims, wherein - binding of the anti-cTnT antibody to skTnT is prevented by steric inhibition when the anti-skTnT antibody is bound to the conserved skTnT peptide sequence.

6. The method of any one of the proceeding claims, wherein the anti-skTnT antibody is capable of binding to an epitope within the conserved skTnT peptide sequence (skTnT epitope), preferably wherein - the skTnT epitope shares at least 75% sequence identity to the conserved peptide sequence in cTnT, and / or - the anti-cTnT antibody is capable of binding to an epitope within the conserved cTnT peptide sequence (cTnT epitope) and wherein the skTnT epitope comprises and / or is at least partially overlapping with a peptide sequence within skTnT that is conserved in the cTnT epitope.

7. The method of any one of the proceeding claims, wherein - the anti-cTnT antibody is not capable of binding to an epitope within the skTnT peptide sequence (comprised in the conserved skTnT peptide sequence(s)) as set forth in SEQ ID NO: 5 and / or 6 in the presence of the anti-skTnT antibody, and / or - under identical experimental conditions the anti-cTnT antibody binds to an epitope within the cTnT peptide sequence (comprised in the conserved cTnT peptide sequence) as set forth in SEQ ID NO: 4 with a lower KD compared to an epitope within the skTnT peptide sequence (comprised in the conserved skTnT peptide sequence(s)) as set forth in SEQ ID NO: 5 and / or 6.

8. The method of any one of the proceeding claims, wherein the anti-skTnT antibody is a monoclonal antibody and / or the anti-cTnT antibody is a monoclonal antibody.

9. The method of any one of the proceeding claims, wherein in step a) - the sample is contacted with the anti-cTnT antibody concomitantly with the anti-skTnT antibody, or - the sample is contacted with the anti-skTnT antibody before the sample, with the anti- skTnT antibody, is contacted with the anti-cTnT antibody.

10. The method of any one of the proceeding claims, further comprising the step of c) comparing the determined amount of cTnT with a reference, preferably wherein an increased amount of skTnT determined in the sample compared to the reference is indicative for a skeletal muscle damage.

11. The method of any one of the proceeding claims, wherein the method is a method of detecting, diagnosing and / or monitoring a disease associated with cTnT, preferably cardiac muscle damage.

12. The method of any one of the proceeding claims, wherein the sample - is a sample selected from the group consisting of serum, plasma, whole blood, interstitial fluid and urine, preferably a serum or plasma sample, and / or - comprises or is suspected of comprising skTnT, and / or - is or is suspected of being a sample obtained from a subject having a skeletal muscle damage, preferably induced by physical exercise and / or by drug use and / or a skeletal muscle disease (SDM).

13. Use of an antibody against skeletal Troponin T (anti-skTnT antibody) for - determining the amount of cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), and / or - preventing skeletal Troponin T (skTnT) interference in determining the amount of cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), and / or - maintaining or improving specificity in determining the amount of cardiac Troponin T (cTnT) in a sample using an antibody against cTnT (anti-cTnT antibody), and / or - maintaining or improving diagnostic accuracy and / or diagnostic specificity for a disease associated with cardiac Troponin T (cTnT) using an antibody against cTnT (anti-cTnT antibody),wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT, preferably wherein said use comprises the method of any one of claims 1 to 10.

14. A composition comprising an antibody against skeletal Troponin T (anti-skTnT antibody) and an antibody against cardiac Troponin T (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby preventing binding of the anti-cTnT antibody to skTnT.

15. A composite composition comprising a first composition and a second composition, wherein said first composition comprises an antibody against skeletal Troponin T (anti- skTnT antibody) and wherein said second composition comprises an antibody against cardiac Troponin T (anti-cTnT antibody), wherein the anti-cTnT antibody is capable of binding to a cTnT peptide sequence conserved between cTnT and skTnT (conserved cTnT peptide sequence), wherein the anti-skTnT antibody is not capable of binding to said conserved cTnT peptide sequence, and wherein the anti-skTnT antibody is capable of binding to a skTnT peptide sequence conserved between skTnT and cTnT (conserved skTnT peptide sequence), thereby being capable of preventing binding of the anti-cTnT antibody to skTnT.

Images