Adamts13 cub domain variants and uses thereof

Abstract

The disclosure provides ADAMTS13 protein variants comprising one or more N- linked glycosylation sites in part of the CUB domain, e.g., wherein the CUB domain comprises amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326- 1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 (as defined by SEQ IN NO: 43). The disclosure further provides compositions comprising ADAMTS13 protein variants, methods for their preparation and uses thereof.

Description

[0001]ADAMTS13 CUB domain variants and uses thereof Field The disclosure relates to the field of therapy. More specifically, the disclosure relates to the field of therapy of disorders in which von Willebrand Factor (VWF) is involved. The disclosure relates to modified proteases involved in maintaining hemostasis, specifically to modified proteases which display strongly reduced binding of autoantibodies while retaining activity, and their use in treatment of disease. Background Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a rare but a life-threatening autoimmune disease that results from the development of autoantibodies directed towards ADAMTS13 (A Disintegrin And Metalloproteinase with ThromboSpondin type 1 motifs, member 13). ADAMTS13 is a metalloprotease that proteolytically cleaves the Tyr1605-Met1606 bond in the A2 domain of Von Willebrand Factor (VWF). VWF is a multimeric protein that mediates the adhesion of blood platelets to a damaged vessel. The multimeric size of VWF is directly proportional to its biological activity, the larger multimers being highly active in promoting the adhesion of platelets to a damaged vessel wall. In normal individuals, multimer size of VWF is controlled by the VWF cleaving protease ADAMTS13. Processing of VWF multimers in patients with iTTP is impaired due to the presence of pathogenic autoantibodies directed towards ADAMTS13 that develop in these patients. The persistence of high molecular weight VWF multimers in iTTP patients with autoantibodies directed towards ADAMTS13 is linked to excessive thrombus formation in the microvasculature presenting with life-threatening microvascular thrombosis. Current management of iTTP involves plasma exchange (PEX) and immunosuppression with high dose glucocorticoids. Plasma exchange provides a source of exogenous ADAMTS13 which actions are short-lived due to the persistent presence of circulating pathogenic antibodies targeting ADAMTS13, including exogenous ADAMTS13. In addition to plasma exchange, Rituximab, a B-cell depleting anti-CD20 therapeutic monoclonal antibody, is used in the treatment of iTTP. Rituximab is also being used to prevent relapses in patients with iTTP. Recently, Caplacizumab, a humanized anti-VWF nanobody which blocks platelet binding to VWF has been shown to accelerate normalization of platelet counts 1.55 fold (Scully et al., 2019). Bleeding provides a side-effect of treatment with Caplacizumab (Mazepa et al., 2019). Mazepa et al showed that bleeding was the primary adverse effect of caplacizumab therapy and occurred in 65% (vs 48% in the placebo arm) in HERCULES clinical trial. Mucocutaneous bleeding including epistaxis and gingival bleeding were the most common events, and most bleeding was of mild to moderate severity that resolved without intervention. Three subjects that developed severe bleeding on caplacizumab received VWF concentrate (severe epistaxis), tranexamic acid (for gingival bleeding), and a red cell transfusion (for upper gastrointestinal bleeding). Overall, most caplacizumab-related bleeding resolve without intervention (though it may be necessary to withhold the drug), whereas topical vasoconstrictors and antifibrinolytics are effective in others, with VWF concentrates reserved for patients with severe, refractory bleeding (e.g. Dutt et al, 2021). Despite the advancements in treatment of patients with iTTP, current treatment regimens are thus still suboptimal. There is clearly a need for treatment that quickly re-establishes ADAMTS13 activity that would help to accelerate the normalization of platelet counts in patients with iTTP. Autoantibody resistant ADAMTS13 variants have been reported in the literature (Jian et al., 2012). The spacer domain of ADAMTS13 provides a major site for the binding of pathogenic autoantibodies. Conservative mutations in 5 residues within the spacer domain has created a so-called Gain-of-Function (GoF) variant that was claimed to be resistant to the binding of pathogenic autoantibodies that develop in patients with iTTP (Jian et al., 2012). This GoF variant of ADAMTS13 is also described in US Patent US 9,546,360. However, follow-up experiments revealed that this GoF variant of ADAMTS13 is still targeted by patient-derived autoantibodies and does not resist their inhibitory action (Graça et al., 2019). WO 2021 / 242092 describes ADAMTS13 variants that contain N-linked glycans in the spacer domain that reduce binding of autoantibodies to this domain. However, pathogenic autoantibodies that bind to other domains of ADAMTS13 have also been reported, e.g. in 20-40% of iTTP patient (see e.g. Thomas et al. 2015 and Pos et al. 2011). Summary The present disclosure provides improved ADAMTS13 protein variants that show reduced binding by autoantibodies as compared to wild-type ADAMTS13. Thus, the provided ADAMTS13 variants effectively escape binding of autoantibodies while retaining ADAMTS13 activity. The disclosure provides ADAMTS13 protein variants comprising one or more N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises amino acids 75 to 1427 of the ADAMTS13 amino acid sequence as shown in figure 1 (as defined by SEQ ID NO: 43) or is a full length ADAMTS13 protein variant comprising one or more N-linked glycosylation sites in part of the CUB domain, and optionally additional mutations, as described herein. In some embodiments, an ADAMTS13 protein variant comprises one or more additional N-linked glycosylation sites compared to wild-type ADAMTS13 and / or one or more existing N-linked glycosylation sites are shifted as compared to wild- type ADAMTS13 in a spacer domain comprising amino acid residues S556 to A685 of ADAMTS13 as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, the disclosure provides an ADAMTS13 protein variant comprising one or more N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1320-1322 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, and that further comprises one or more further mutations that reduce binding by autoantibodies directed to the spacer domain. In some embodiments, the disclosure provides an ADAMTS13 protein variant comprising one or more N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1320-1322 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, wherein further one or more N-linked glycosylation sites are added as compared to wild-type ADAMTS13 and / or one or more existing N-linked glycosylation sites are shifted as compared to wild-type ADAMTS13 in a spacer domain comprising amino acid residues S556 to A685 of ADAMTS13 as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, the disclosure provides a nucleic acid construct comprising a nucleic acid sequence encoding an ADAMTS13 protein variant according to the invention. In some embodiments, the disclosure provides a pharmaceutical composition comprising an ADAMTS13 protein variant or a nucleic acid construct according to the disclosure and one or more pharmaceutically acceptable carriers, adjuvants, excipients and / or diluents. In some embodiments, the disclosure provides a method for reducing autoantibody binding, in particular binding by anti-CUB domain antibodies, to ADAMTS13 or a variant thereof said method comprising introducing into the ADAMTS13 or variant one or more, preferably one or two, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272- 1276, 1295-1297, 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, thereby reducing autoantibody-binding to the ADAMTS13 or variant In some embodiments, the disclosure provides a method for reducing plasma clearance of ADAMTS13 or a variant thereof said method comprising introducing into said ADAMTS13 or variant one or more N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, thereby reducing plasma clearance of the ADAMTS13 or variant. In some embodiments, an ADAMTS13 is an ADAMTS13 protein variant with reduced binding to auto-antibodies specific for the spacer domain as compared to wild-type ADAMTS13. In some embodiments, the disclosure provides an ADAMTS13 protein variant or nucleic acid construct according to the disclosure for use in therapy. In some embodiments, the disclosure provides an ADAMTS13 protein variant or nucleic acid construct according to the disclosure for use as an antithrombotic agent. In some embodiments, the disclosure provides an ADAMTS13 protein variant or nucleic acid construct according to the disclosure for use in the treatment of a disorder characterized by aberrant Von Willebrand Factor (VWF) activity and / or VWF processing. In some embodiments, the disclosure provides a method for the treatment of a disorder characterized by aberrant Von Willebrand Factor (VWF) activity and / or VWF processing comprising administering to a subject in need thereof a therapeutically effective amount of an ADAMTS13 protein variant according to the disclosure. In some embodiments, the disclosure provides a method of treatment of a disorder characterized by aberrant Von Willebrand Factor (VWF) activity and / or VWF processing in a patient that inadequately responds to treatment that reduces ADAMTS13 autoantibody binding to the spacer domain comprising administering to the patient a therapeutically effective amount of an ADAMTS13 protein variant according to the disclosure. Detailed description The present disclosure provides novel ADAMTS13 protein variants that are less vulnerable to binding by autoantibodies than wild-type ADAMTS13. Although essentially all iTTP patients have autoantibodies against the spacer domain modification of the spacer domain may not suffice to eliminate autoantibody binding to ADAMTS13. This is believed to be due to antibodies against other ADAMTS13 domains, which are developed in 20-40% of iTTP patients (see e.g. Thomas et al. (2015) and Pos et al.2011). One of these domains is the CUB domain (for complement C1r / C1s proteases, sea Urchin, and Bone morphogenic protein), which can be subdivided into a CUB1 domain and a CUB2 domain. Antibodies against the CUB domain do not directly inhibit ADAMTS13, but increase clearance rates of ADAMTS13 from plasma thereby lowering functional levels of ADAMTS13. Additionally, these antibodies are able to open the conformation of ADAMTS13, which results in increased accessibility of the immunodominant epitope on the spacer domain (Roose et al.2020). Under quiescent conditions ADAMTS13 circulates in blood in a closed conformation. Upon binding to its substrate von Willebrand factor ADAMTS13 transitions to an open conformation (South et al., 2014). The conformational status of ADAMTS13 is dependent on pH; at pH 6.0 ADAMTS13 is present in an open conformation whereas at pH 7.5 ADAMTS13 is present in a closed conformation (Joshua et al., 2014; Muia et al., 2013). It has been previously shown that the activity (as measured by conversion of the synthetic peptide substrate FRETS- VWF73) of ADAMTS13 in a closed conformation (at pH 7.5) is lower when compared to its activity in an open conformation at pH 6.0 (Joshua et al., 2014; Muia et al., 2013). The present inventors have introduced N-glycans in the residues surrounding the spacer-CUB interface of ADAMTS13 to reduce auto-antibody binding. Preventing binding of autoantibodies to the CUB domains may results in longer presence of functional ADAMTS13 in patients. Residues for addition of N-glycans were selected based on two criteria. Firstly, the N-glycans were preferably introduced around the modeled spacer-CUB interface, in order to minimize the chance of conformational alterations within this part of the molecule. Secondly, the amino acid side-chain had to be facing outward, as mutating an inward facing sidechain could potentially affect protein stability and / or the efficacy of N-glycan attachment. Based on these selection criteria, a number of locations were selected for the insertion of an N-glycosylation site. As demonstrated in the Examples herein, although several ADAMTS13 protein variants having one of the selected added N-glycosylation sites were unsuccessful (e.g. due to lack of expression or inability to reduce autoantibody binding), several ADAMTS13 protein variants were designed that do not negatively affect ADAMTS13 activity and that reduce binding of autoantibodies to the CUB domain. Moreover, it is expected that 20-40% of iTTP patients would not fully respond to treatment with ADAMTS13 protein variants that show reduced binding by autoantibodies that target the spacer domain, even though >95% of patients have such antibodies. In the Examples herein, it is established that such ADAMTS13 protein variants are still vulnerable to autoantibodies to the CUB domain and therefore could show fast clearance, and consequently reduced activity in vivo. The strategy to reduce autoantibody binding to the CUB domain of the present invention is demonstrated to also increase activity of ADAMTS13 protein variants with reduced autoantibody binding to the spacer domain. By reducing anti-CUB domain autoantibody binding the present disclosure thus allows potentially an increase in overall clinical efficiency of treatment of impaired ADAMTS13 activity to up to 100% of iTTP patients, when strategies to reduce autoantibody binding to the spacer and CUB domains are combined, preferably in a single ADAMTS13 protein variant. In some embodiments, the disclosure provides an ADAMTS13 protein variant comprising one or more N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. some embodiments, one or more N-linked glycosylation sites are present at amino acid residues 1246, 1247, 1248, 1249, 1250, 1251, 1252, 1253, 1254, 1255, 1256, 1257, 1258, 1272, 1273, 1274, 1275, 1276, 1295, 1296, 1297, 1326, 1327, 1328, 1361, 1362, 1363, 1364, 1365, 1366, 1367, 1368, 1369, 1370, 1392, 1393 and / or 1394 as indicated in figure 1 or as defined in SEQ ID NO: 43. As used herein, "to comprise" and its conjugations is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. In addition, the verb “to consist” may be replaced by “to consist essentially of” meaning that a compound or adjunct compound as defined herein may comprise additional component(s) than the ones specifically identified, said additional component(s) not altering the unique characteristic of the disclosure. The articles “a” and “an” are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, “an element” means one element or more than one element. The word “approximately” or “about” when used in association with a numerical value (e.g. approximately 10, about 10) preferably means that the value may be the given value (e.g.10), plus or minus 5% of the value (e.g.10, plus or minus 5%), preferably plus or minus 1% of the value. The term “at least” when used in association with a numerical value or percentage value (e.g. at least 90%) should be understood to comprise the stated numerical value and all higher values. Hence, alternative wordings for e.g. “at least 90%” shall be understood as “90% or more” or “≥90%”. The use of the alternative (e.g., "or") should be understood to mean either one, both, or any combination thereof of the alternatives. The term “protein” as used herein refers to compounds comprising amino acids joined via peptide bonds. A protein encoded by a gene is not limited to the amino acid sequence encoded by a gene, but may include post-translational modifications of the protein. The term “subject” as used herein refers to the recipient of an ADAMTS13 protein variant or encoding nucleic acid according to the disclosure and encompasses humans and animals. The subject is preferably a mammal, more preferably a human. The term "therapeutically effective amount," as used herein, refers to an amount of an ADAMTS13 protein variant being administered sufficient to relieve one or more of the symptoms of the disease or condition being treated to some extent. This can be a reduction or alleviation of symptoms, reduction or alleviation of causes of the disease or condition or any other desired therapeutic effect. As used herein, the term “treatment” refers to inhibiting the disorder, i.e., halting or reducing its development or at least one clinical symptom of the disease or condition, and / or to relieving symptoms of the disease or condition. As used herein the terms “ADAMTS13” and “ADAMTS13 protein” refers to a protein encoded by the ADAMTS13 gene. ADAMTS13 is a member of the metalloproteinase gene family, ADAM (a disintegrin and metalloproteinase), a family consisting of membrane-anchored proteases with different functions. ADAMTS family members are further characterized by the presence of one or more thrombospondin 1-like (TSP1) domain(s) at the C-terminus and the absence of an EGF repeat, a transmembrane domain and a cytoplasmic tail, present in ADAM metalloproteinases. ADAMTS13 is the only ADAMTS member to possess two C- terminal CUB domains (for complement C1r / C1s proteases, sea Urchin, and Bone morphogenic protein), and possesses VWF (von Willebrand factor) cleaving protease activity (Kelwick et al, 2005). The terms “wild-type ADAMTS13” and “wild-type ADAMTS13 protein” refer to naturally occurring, human ADAMTS13. Figure 1 provides the amino acid sequence of full length wild-type ADAMTS13, as defined by SEQ ID NO: 43. The “Complement component Clr / Cls, Uegf, and Bone morphogenic protein 1 (CUB) domain” of ADAMTS13 refers to part of the ADAMTS13 amino acid sequence comprising residues C1192 to T1427 of the amino acid sequence as shown in figure 1 or as defined by SEQ ID NO: 43, which is the C-terminal part of the ADAMTS13 amino acid sequence. The CUB domain may be subdivided into in a CUB1 domain and a CUB2 domain. In some embodiments, a CUB1 domain refers to a part of the ADAMTS13 amino acid sequence that comprises amino acid residues 1192 – 1298 of SEQ ID NO:43. In some embodiments, a CUB2 domain refers to a part of the ADAMTS13 amino acid sequence that comprises amino acid residues 1299 – 1427 of SEQ ID NO:43. As used herein the term “ADAMTS13 protein variant” refers to a variant of ADAMTS13 that has an amino acid sequence that differs from the amino acid sequence of wild-type ADAMTS13 in that it has at least one N-glycosylation site that is not present in wild-type ADAMTS13. In some embodiments, an ADAMTS13 protein variant according to the present disclosure comprises at least amino acids 75 to 1427 of the ADAMTS13 amino acid sequence as shown in figure 1 (or as defined by SEQ ID NO: 43), and comprises one or more N-linked glycosylation sites in part of the CUB domain. In some embodiments, an ADAMTS13 protein variant comprises additional mutations, preferably as described herein. Residues 1-74 of SEQ ID NO:43 encode the signal peptide and propeptide. In some embodiments, an ADAMTS13 protein variant according to the disclosure is a full length ADAMTS13 protein variant. In some embodiments, a full length ADAMTS13 protein variant comprises the full amino acid sequence with residues 1 to 1427 of ADAMTS13, as shown in figure 1 or as defined by SEQ ID NO: 43, and comprises one or more N-linked glycosylation sites in part of the CUB domain, and optionally additional mutations, preferably as described herein. ADAMTS13 protein variants according to the disclosure comprising one of more N-linked glycosylation sites as defined herein are herein also referred to as “CUB-NGLY protein variants” or “CUB-NGLY ADAMTS13 protein variants”. In amino acid sequences or protein variants as provided herein, amino acids are denoted by single-letter or three-letter symbols. These single-letter and three- letter symbols are well known to the person skilled in the art and have the following meaning: A (Ala) is alanine, C (Cys) is cysteine, D (Asp) is aspartic acid, E (Glu) is glutamic acid, F (Phe) is phenylalanine, G (Gly) is glycine, H (His) is histidine, I (Ile) is isoleucine, K (Lys) is lysine, L (Leu) is leucine, M (Met) is methionine, N (Asn) is asparagine, P (Pro) is proline, Q (Gln) is glutamine, R (Arg) is arginine, S (Ser) is serine, T (Thr) is threonine, V (Val) is valine, W (Trp) is tryptophan, Y (Tyr) is tyrosine. All positions of amino acid residues indicated herein refer to the numbering of amino acid residues in the sequence of wild-type ADAMTS13 depicted in figure 1 or as defined by SEQ ID NO: 43. Mutations, in particular substitutions of an amino acid by another amino acid, are indicated herein in a way that is standard in the art, i.e., by indicating the amino acid present in wild-type ADAMTS13 sequence, the position of the amino acid in the sequence, and the amino acid that is introduced at the position. E.g. “R568K” indicates that the arginine at position 568 is substituted by a lysine. As another example, 1251N indicates that at position 1251 an asparagine is introduced. As another example, “568REY570 to 568NET570” indicates that the sequence arginine-glutamic acid-tyrosine at positions 568-570 is substituted by the sequence asparagine-glutamic acid-threonine. The mutations introduced in an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure, including both mutations that are made to add and / or shift one or more N-linked glycosylation sites and any further mutations as described herein as compared to wild-type ADAMTS13, preferably result in an ADAMTS13 protein variant comprising an amino acid sequence that is at least 90% identical to the sequence of the corresponding amino acid sequence in wild-type ADAMTS13. In some embodiments, an ADAMTS13 protein variant according to the present disclosure preferably has at least 90% sequence identity to the corresponding sequence of wild-type ADAMTS13. In some embodiments, a full length ADAMTS13 protein variant provided by the present disclosure has at least 90% sequence identity to a full length wild-type ADAMTS13. In some embodiments, an ADAMTS13 protein variant provided by the present disclosure comprises at least amino acids 75 to 1427 of the ADAMTS13 amino acid sequence as shown in figure 1 or as defined by SEQ ID NO: 43, with the indicated mutations, preferably has at least 90% sequence identity to amino acids 75 to 1427 of wild-type ADAMTS13. Said sequence identity is preferably at least 90%, more preferably at least 95%, more preferably at least 96%, more preferably at least 97%, more preferably at least 98%. The term “% sequence identity” is defined herein as the percentage of amino acids in an amino acid sequence that is identical with the amino acids in a reference amino acid sequence or an amino acid sequence of interest, after aligning the sequences to achieve the maximum percent sequence identity. Methods and computer programs for alignments are well known in the art. The skilled person understands that consecutive amino acid residues in one amino acid sequence are compared to consecutive amino acid residues in another amino acid sequence. “N-linked glycosylation” refers to the attachment of an oligosaccharide moiety to a nitrogen atom, typically the N4 of an asparagine residue. The terms “N-linked glycosylation site” and “N glycosylation site” are used interchangeably and refer to a site in the ADAMTS13 protein variant where N-linked glycosylation is possible. Such site has the amino acid sequence NXT or NXS, wherein X is any amino acid except P. N-linked glycosylation is a posttranslational modification and N-linked glycans of a protein can modulate the folding, cell attachment and / or function of a protein. N-linked glycans can have different combinations of mannose, N- acetylglucosamine (GlcNAc), galactose, fucose and sialic acid residues. Several N- linked glycans have been identified on ADAMTS13 (Verbij et al. 2016)), attached to asparagine residues 142, 146, 552, 579, 614, 667, 707, 828, 1235 and 1354 (see Figure 2), as well as several other types of glycosylation, including O-glycosylation and S- and C- mannosylation. Figure 2 also shows the most common and other structures of N-glycans identified in ADAMTS13. The one or more N-linked glycosylation sites that are present in an ADAMTS13 protein variant according to the present disclosure in addition to N-glycosylation sites present in wild-type ADAMTS13 are indicated by reference to the residue of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In particular, the residue is indicated that corresponds to the asparagine of the NXT of NXS sequence. E.g. an N-linked glycosylation site at amino acid residue 1251 means that the asparagine is present at residue 1251. Further the X of the sequence NXT or NXS is present at amino acid residue 1252 and the T or S of sequence NXT or NXS is present at amino acid residue 1253. In some embodiments, an ADAMTS13 protein variants according to the present disclosure or used in accordance with the present disclosure, comprises one or more N-linked glycosylation sites that are not present in wild-type ADAMTS13. This means that an N glycosylation site (NXT or NXS, wherein X is any amino acid except P) is present at amino acid residues at which it is not present in the wild- type ADAMTS13. This is achieved by introducing one or more N-linked glycosylation site in the sequence of ADAMTS13. Preferably an ADAMTS13 protein variant according to the present disclosure comprises one to five N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, more preferably between one and three, more preferably one or two. I.e. said one to five, between one and three, and one or two N-linked glycosylation sites are present at amino acid residues 1246, 1247, 1248, 1249, 1250, 1251, 1252, 1253, 1254, 1255, 1256, 1257, 1258, 1272, 1273, 1274, 1275, 1276, 1295, 1296, 1297, 1326, 1327, 1328, 1361, 1362, 1363, 1364, 1365, 1366, 1367, 1368, 1369, 1370, 1392, 1393 and / or 1394 as indicated in figure 1 or in SEQ ID NO: 43. In some embodiments, introduction of an N-linked glycosylation site means that an N-linked glycosylation site is introduced in the ADAMTS13 protein variant of the present disclosure that is not present in wild-type ADAMTS13, in some embodiments without removing any naturally occurring N-linked glycosylation sites that are present in wild-type ADAMTS13. In some embodiments, addition of an N-linked glycosylation site can be achieved by introducing one or more mutations in the amino acid sequence as compared to wild-type ADAMTS13, such that an N-linked glycosylation site is introduced. Such mutation can be one or more substitutions of amino acid residues by other amino acid residues, insertion of one or more amino acid residues or deletion of one or more amino acid residues or a combination thereof, in such a way that an N-linked glycosylation site is introduced in the ADAMTS13 sequence that is not present in wild-type ADAMTS13. In some embodiments, an N-linked glycosylation site is introduced by one or more substitutions of an amino acid residue with another amino acid residue. In some embodiments, any amino acid can be substituted with an asparagine (N) residue to introduce an asparagine (N) as the first residue in the N-linked glycosylation site NXS or NXT as defined herein. In some embodiments, a proline can be substituted with any other amino acid to remove a potential proline as the second residue in the N-linked glycosylation site NXS or NXT as defined herein. In some embodiments, any amino acid other than serine (S) and threonine (T) can be substituted with serine (S) or threonine (T) to introduce a serine (S) or threonine (T) as the third residue in the N-linked glycosylation site NXS or NXT as defined herein, or a combination thereof. Both NXS and NXT sites can be introduced in an ADAMTS13 protein variant in accordance with the present disclosure or used in accordance with the present disclosure. Without being bound by a particular theory NXT appears to result in more efficient N-glycan addition when compared to NXS. In some embodiments, one more N-linked glycosylation sites as defined herein have the sequence NXT. A skilled person is well capable of designing appropriate mutations in the ADAMTS13 sequence to introduce one or more N-linked glycosylation sites at the residues defined herein. In some embodiments, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure has a reduced binding by autoantibodies as compared to wild-type ADAMTS13. In some embodiments, an ADAMTS13 protein variant provided by the present disclosure is characterized in that it has reduced binding by autoantibodies. In some embodiments, an ADAMTS13 protein variants is characterized in that it has reduced binding by autoantibodies, when assessed in an ELISA assay under conditions as described in Examples 5 and 6, it shows reduced binding of autoantibodies specific for ADAMTS13 protein as compared to wild-type ADAMTS13 protein. In other words, “Having a reduced binding by autoantibodies” as used herein means that binding of autoantibodies specific for ADAMTS13 show reduced binding to the ADAMTS13 protein variant of the present disclosure or used in accordance with the present disclosure as compared to wild-type ADAMTS13. In particular, the autoantibodies are autoantibodies present in serum of patients suffering from immune-mediated thrombotic thrombocytopenic purpura (iTTP). Preferably the autoantibodies are anti-CUB antibodies, i.e., they bind to the CUB1 domain of ADAMTS13 and / or the CUB2 domain of ADAMTS13. “Reduced” as used herein preferably means that the binding is reduced by at least 10%, preferably at least 15%, more preferably at least 20%, more preferably at least 25%, more preferably at least 50%, more preferably at least 75%, more preferably at least 80%, more preferably at least 85%, more preferably at least 90%, most preferably at least 95%. Thus, “reduced binding by autoantibodies as compared to wild-type ADAMTS13” preferably means that the binding by autoantibodies, as evidenced e.g. by the reactivity of the ADAMTS13 protein variant according to the present disclosure with iTTP patent sera as detailed herein below, is reduced by at least 10%, more preferably at least 15%, 20%, 25%, 50%, 75%, 80%, 85%, 90% or 95% as compared to binding of wild-type ADAMTS13 protein. Reduction of binding by autoantibodies in serum or plasma of iTTP patient can for instance be determined by measuring reactivity of the ADAMTS13 protein variant with serum or sera of iTTP patients in an assay as described in the Examples herein. In brief, binding of autoantibodies to ADAMTS13 can be detected by immobilizing ADAMTS13 directly on a surface or indirectly through immobilizing a monoclonal or polyclonal antibody directed towards ADAMTS13 (or a V5-tag or His-tag or any other tag). Subsequently, the immobilized ADAMTS13 is incubated with a patient-derived biological fluid, preferably plasma or serum, allowing for binding of anti-ADAMTS13 immunoglobulins to immobilized ADAMTS13. Bound patient-derived immunoglobulins reactive with ADAMTS13 can subsequently be detected employing conjugated or labelled antibodies that specifically recognize human immunoglobulins. An example of such an assay is presented in Example 7. Alternatively, monoclonal patient derived anti-CUB antibodies can be prepared and used to test binding to ADMTS13 or a variant according to the present disclosure in an ELISA. An example is presented in Examples 5 and 6. Other methods to detect antigen-specific antibodies in biological fluids from patients and normal individuals have been extensively described in the literature and can be applied for the detection of antibodies directed towards ADAMTS13 (e.g. Burbelo PD and O'Hanlon TP, 2014) Because autoantibodies in serum of iTTP patient are heterogenous, it is preferred that binding of autoantibodies to the ADAMTS13 protein variant of the present disclosure is determined in serum of multiple iTTP patient, for instance in serum or plasma samples of at least 5 different iTTP patients. In some embodiments, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure has proteolytic activity against Von Willebrand Factor (VWF) that is at least 10% of the proteolytic activity against VWF of wild-type ADAMTS13 protein. In some embodiments, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure has proteolytic activity against Von Willebrand Factor (VWF) that is at least 10% of the proteolytic activity against VWF of wild-type ADAMTS13 protein in the absence of autoantibodies. In some embodiments, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure has proteolytic activity against Von Willebrand Factor (VWF) that is at least 10% of the proteolytic activity against VWF of wild-type ADAMTS13 protein in the presence of autoantibodies. In some embodiments, an ADAMTS13 protein variant or use of an ADAMTA13 protein variant has proteolytic activity against Von Willebrand Factor (VWF) that is at least 20%, such as at least 30%, such as at least 40%, such as at least 50% of the proteolytic activity against VWF of wild-type ADAMTS13 protein. As used herein, “proteolytic activity against VWF” refers to the ability of ADAMTS13 or an ADAMTS13 protein variant to cleave VWF. As used herein “x% proteolytic activity against VWF of wild-type ADAMTS13 protein” refers to x% of proteolytic activity against VWF compared to recombinant wild-type ADAMTS13 under the same conditions. I.e. the proteolytic activity against VWF of the ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure is compared with the proteolytic activity against VWF of the recombinant wild-type ADAMTS13 protein under the same conditions, including determined using the same assay, for the same amount of time, using the same concentration of protein, etc. A skilled person is well capable of assessing the proteolytic activity of wild-type ADAMTS13 and an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure under the same conditions such that this activity can be compared. Proteolytic activity against VWF can, for instance, be determined using an assay as described herein the Examples with FRETS-VWF73 (as described in Kokame et al. 2005) and VWF multimer assay (as described in Graça et al.2019). Proteolytic activity towards the VWF can for instance be measured using a generally available FRETS-VWF73 substrate (AnaSpec, Fremont, Ca, USA), for instance in accordance with the FRETS-VWF73 substrate assay protocol as described in the Examples herein. In some embodiments, an ADAMTS13 protein variant according to the disclosure comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. I.e. said one or more N-linked glycosylation sites are present at amino acid residues 1246, 1247, 1248, 1249, 1250, 1251, 1252, 1253, 1254, 1255, 1256, 1257, 1258, 1272, 1273, 1274, 1275, 1276, 1295, 1296, 1297, 1326, 1327, 1328, 1361, 1362, 1363, 1364, 1365, 1366, 1367, 1368, 1369, 1370, 1392, 1393 and / or 1394 as indicated in figure 1 or in SEQ ID NO: 43. In some embodiments, one or more N glycosylation sites (NXT or NXS, wherein X is any amino acid except P) is or are present at amino acid residues in the CUB domain at which N glycosylation sites are not present in the CUB domain of wild-type ADAMTS13. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1248-1257, 1274-1276, 1295-1297, 1326-1328, 1364-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1248-1255, 1274-1275, 1295-1296, 1326-1327, 1364-1367 and / or 1392-1393 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in the CUB domain at amino acid residue 1248, 1249, 1250, 1251, 1255, 1274, 1295, 1326, 1364, 1365, 1366, 1368 and / or 1392 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in the CUB domain at amino acid residue 1251, 1255, 1295, and / or 1368 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in the CUB domain at amino acid residue 1248, 1249, 1250, 1251, 1255, 1295, and / or 1368 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in the CUB domain at amino acid residue 1251, 1255, 1274, 1295, and / or 1368 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in the CUB domain at amino acid residue 1251, 1255, 1295, 1364, 1365, 1366 and / or 1368 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in the CUB domain at amino acid residue 1251, 1255, 1295, 1364, 1365, 1366, 1368 and / or 1392 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. As demonstrated in the Examples, in some embodiments, an ADAMTS13 protein variant of the disclosure comprises one or more N-linked glycosylation sites in the CUB1 domain and / or one or more N-linked glycosylation sites in the CUB2 domain. Such ADAMTS13 protein variants have shown to largely reduce the binding by anti-CUB domain autoantibodies, see e.g., figure 8. Hence, in some embodiments, an ADAMTS13 protein variant of the disclosure comprises one or more N-linked glycosylation site in part of the CUB1 domain comprising amino acid residues 1246-1258, 1272-1276, and / or 1295-1297 of ADAMTS13 as shown in figure 1 (as defined by SEQ ID NO: 43) and one or more N-linked glycosylation site in part of the CUB2 domain comprising amino acid residues 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. I.e. one or more N-linked glycosylation sites are present at amino acid residues 1246, 1247, 1248, 1249, 1250, 1251, 1252, 1253, 1254, 1255, 1256, 1257, 1258, 1272, 1273, 1274, 1275, 1276, 1295, 1296, 1297 as indicated in figure 1 (or in SEQ ID NO: 43) and one or more N-linked glycosylation sites are present at amino acid residues 1326, 1327, 1328, 1361, 1362, 1363, 1364, 1365, 1366, 1367, 1368, 1369, 1370, 1392, 1393 and / or 1394 as indicated in figure 1 or in SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or two N-linked glycosylation site in part of the CUB1 domain comprising amino acid residues 1246-1258, 1272-1276, and / or 1295-1297 of ADAMTS13 as shown in figure 1 (or as defined by SEQ ID NO: 43) and one or two N-linked glycosylation site in part of the CUB2 domain comprising amino acid residues 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one N-linked glycosylation site in part of the CUB1 domain comprising amino acid residues 1246-1258, 1272-1276, and / or 1295-1297 and one N-linked glycosylation site in part of the CUB2 domain comprising amino acid residues 1326-1328, 1361- 1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1248-1257, 1274-1276, and / or 1295- 1297 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43 and one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1326-1328, 1364-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1248-1255, 1274-1275, and / or 1295-1296 of the ADAMTS13 sequence as shown in figure 1 (as defined by SEQ ID NO: 43) and one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1326-1327, 1364-1367 and / or 1392-1393 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1248, 1249, 1250, 1251, 1255, 1274, and / or 1295 of the ADAMTS13 sequence as shown in figure 1 (as defined by SEQ ID NO: 43) and one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1326, 1364, 1365, 1366, 1368 and / or 1392 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1251, 1255, and / or 1295 of the ADAMTS13 sequence as shown in figure 1 (as defined by SEQ ID NO: 43) and an N-linked glycosylation sites at amino acid residue 1368 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1248, 1249, 1250, 1251, 1255, 1295 of the ADAMTS13 sequence as shown in figure 1 (as defined by SEQ ID NO: 43) and an N-linked glycosylation site at amino acid residue 1368 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1251, 1255, 1274 and / or 1295 of the ADAMTS13 sequence as shown in figure 1 (as defined by SEQ ID NO: 43) and an N-linked glycosylation site at amino acid residue 1368 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1251, 1255 and / or 1295 of the ADAMTS13 sequence as shown in figure 1 (as defined by SEQ ID NO: 43) and one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1364, 1365, 1366 and / or 1368 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1251, 1255, and / or 1295 of the ADAMTS13 sequence as shown in figure 1 (as defined by SEQ ID NO: 43) and one or more, such as one or two, such as one, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1364, 1365, 1366, 1368 and / or 1392 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant of the disclosure comprise an N-linked glycosylation site at amino acid residue 1251 and an N- linked glycosylation site at amino acid residue 1368. As demonstrated in the Examples herein, such ADAMTS13 protein variant shows a substantially reduction of binding by anti-CUB domain autoantibodies and furthermore shows increased proteolytic activity comparable to wild-type ADAMTS13. In some embodiments, an ADAMTS13 protein variant of the present disclosure comprises an N-linked glycosylation site at amino acid residue 1255 and an N-linked glycosylation site at amino acid residue 1368. As demonstrated in the Examples herein, such ADAMTS13 protein variant shows a substantially reduction of binding by anti-CUB domain autoantibodies. In some embodiments, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure comprises one or more, such as one to five, such as one or two, mutations selected from table 1 or table 2, such as selected from table 1. As exemplified in the Examples herein, it was found that ADAMTS13 protein variants provided by the present disclosure showed substantially reduced binding to antibodies in serum of iTTP patients when the CUB-NGLY variants are combined with ADAMTS13 protein variants that reduce or prevent the binding of anti-spacer targeting autoantibodies, in particular in patients that have a diverse populations of autoantibodies. The introduction of one or more N-glycosylation sites in the CUB domain as defined herein may thus be advantageously combined with other mutations in ADAMTS13, in particular with other mutations that aim to reduced binding by autoantibodies. Hence, in some embodiments, an ADAMTS13 protein variant of the present disclosure is provided that comprises one or more further mutations that reduce binding by autoantibodies in the ADAMTS13 protein variant as compared to binding by autoantibodies to wild-type ADAMTS13, in particular autoantibodies that bind to a domain in ADAMTS13 other than the CUB domain. In some embodiments, an ADAMTS13 protein variant comprises amino acids 75 to 1427 of the ADAMTS13 amino acid sequence as shown in figure 1 (or as defined by SEQ ID NO: 43) or is a full length ADAMTS13 protein variant as defined by SEQ ID NO: 43, and comprises one or more N-linked glycosylation sites in part of the CUB domain, and optionally additional mutations, preferably as described herein. In some embodiments, introduction of one or more N-glycosylation sites in the CUB domain as defined herein is combined with mutations in ADAMTS13 that reduce binding to autoantibodies directed to a spacer domain. The spacer domain is 130 amino acids long, and is known to mediate several crucial interactions required for protease activity of ADAMTS13. It has further been shown that a truncated variant of ADAMTS13, comprising amino acids up to and including the spacer domain, i.e. amino acids 1-685, shows proteolytic activity (E.g. Xiao et al. 2011 and De Maeyer et al.2010). The spacer domain contains surface exposed residues that form the main epitope that is recognized by anti-ADAMTS13 autoantibodies. These residues are also referred to as the exosite-3 domain. This domain contains amino acid residues R568, F592, R660, Y661 and Y665. Alanine mutations of R660, Y661 and Y665 impairs recognition of ADAMTS13 by VWF (Pos et al.2010; Pos et al. 2011). However, conservative amino acid substitutions of the exosite-3 residues have been shown to result in a gain-of-function variant of ADAMTS13 (Jian et al. 2012). Initially it was believed that this variant is also resistant to autoantibodies, but follow-up experiments have revealed that it is still targeted by patient-derived autoantibodies (Graça et al. 2019). Hence, in some embodiments, an ADAMTS13 protein variant of the present disclosure is provided that comprises one or more further mutations that reduce binding by autoantibodies directed to the spacer domain. Also provided are ADAMTS13 protein variants comprising one or more N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1320-1322 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, and that further comprises one or more further mutations that reduce binding by autoantibodies directed to the spacer domain. Reduction of binding by antibodies is as compared to ADAMTS13 that does not comprise said one or more mutations. The spacer domain comprises amino acid residues S556 to A685 of ADAMTS13 as shown in figure 1 or as defined by SEQ ID NO: 43. The one or more mutations in the spacer domain can be a mutation that reduces binding by autoantibodies. In some embodiments, an ADAMTS13 protein variant comprises amino acids 75 to 1427 of the ADAMTS13 amino acid sequence as shown in figure 1 (as defined by SEQ ID NO: 43) or is a full length ADAMTS13 protein variant as defined by SEQ ID NO: 43, but comprising one or more N-linked glycosylation sites in part of the CUB domain, and optionally additional mutations, preferably as described herein. In some embodiments, in an ADAMTS13 protein variant further one or more N-linked glycosylation sites are added as compared to wild-type ADAMTS13 and / or one or more existing N-linked glycosylation sites are shifted as compared to wild- type ADAMTS13 in a spacer domain comprising amino acid residues S556 to A685 of ADAMTS13 as shown in figure 1 or as defined by SEQ ID NO: 43. Adding or shifting of such N-linked glycosylation sites is describes in WO 2021 / 242092, which is incorporated herein by reference. In some embodiments, an ADAMTS13 protein variant according to the present disclosure comprises one to five N-linked glycosylation sites that are added or shifted in the spacer domain as defined herein, such as between one and three, such as one or two, more preferably one. In some embodiments, an ADAMTS13 protein variant according to the present disclosure comprises one to five N-linked glycosylation sites in part of the CUB domain as defined herein, such as between one and three, such as one or two, and one to five N-linked glycosylation sites that are added or shifted in the spacer domain as defined herein, more preferably between one and three, more preferably one or two. In some embodiments, in an ADAMTS13 protein variant according to the present disclosure or used in accordance with the disclosure, the one or more N- linked glycosylation sites are added or shifted as compared to wild-type ADAMTS13 by introducing an N-glycosylation site (NXT or NXS, wherein X is any amino acid except P, as described herein) in the spacer domain or by shifting an N- glycosylation site in the spacer domain to another position. Adding or shifting an N-linked glycosylation site in the spacer domain means that an N glycosylation site (NXT or NXS, wherein X is any amino acid except P) is present at amino acid residues at which it is not present in the spacer domain of wild-type ADAMTS13. As used herein “adding” an N-linked glycosylation site refers to introducing an N-linked glycosylation site that is not present in wild-type ADAMTS13. I.e. the total number of N-linked glycosylation sites in the ADAMTS13 protein variant wherein one or more N-linked glycosylation have been added is higher the number of N-linked glycosylation sites in wild-type ADAMTS13. As used herein “shifting” an N-linked glycosylation site means that an N- linked glycosylation site that is present at particular amino acid residues in wild- type ADAMTS13 is moved to other amino acid residues in the ADAMTS13 amino acid sequences. I.e. the total number of N-linked glycosylation sites in the ADAMTS13 protein variant wherein an N-linked glycosylation has been shifted is the same as the number of N-linked glycosylation sites in wild-type ADAMTS13. In some embodiments, an N-linked glycosylation site is shifted between 1 and 10 amino acid residues. Shifting can be either downstream or upstream as compared to the location of the N-linked glycosylation site in the wild-type ADAMTS13 sequence. In some embodiments, a N-linked glycosylation site is shifted between 1 and 7 amino acids, such as between 1 and 5 amino acids, such as between 1 and 4 amino acids, such as between 1 and 3 amino acids, such as shifted one, two or three amino acid residues, either upstream or downstream as compared to the location of the N-linked glycosylation site in the wild-type ADAMTS13 sequence. In some embodiments, a N-linked glycosylation site is shifted 1 or 2 amino acid residues, such asone amino acid residue. In some embodiments, one or more N-linked glycosylation sites that are added or shifted in the spacer domain as defined herein are added and / or shifted in a part of the spacer domain comprising residues R568 to R670 of the ADAMTS13 sequence, as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, one or more N-linked glycosylation sites that are added or shifted in the spacer domain as defined herein are added and / or shifted at an amino acid residue selected from the group consisting of R568, L591, V604, V605, A606, G607, K608, M609, R636, L637, P638, R639, Y665, L668 and combinations thereof. In some embodiments, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure comprises a N-glycan at an amino acid residue mutation selected from the group consisting of R568N, L591N, V604N, V605N, A606N, G607N, K608N, M609N, R636N, L637N, P638N, R639N, Y665N, L668N and combinations thereof. In some embodiments, additional mutations may be introduced to introduce an N- linked glycosylation site at these amino acids, i.e. in order to introduce the N- linked glycosylation sequence NXT or NXS as described herein above. I.e. one or more N-linked glycosylation sites are added as compared to wild-type ADAMTS13 by introducing a mutation selected from these groups. In some embodiments, one or more N-linked glycosylation sites that are added or shifted in the spacer domain as defined herein are added and / or shifted at an amino acid position selected from the group consisting of 568, 591, 608, 609, 636, 637, 665, 668 as shown in figure 1 (as defined by SEQ ID NO: 43) and combinations thereof, more preferably at an amino acid position selected from the group consisting of 591, 608, 609, 636, 665, 668 as shown in figure 1 (as defined by SEQ ID NO: 43) and combinations thereof, more preferably at an amino acid position selected from the group consisting of 608, 609, 665 as shown in figure 1 (as defined by SEQ ID NO: 43) and combinations thereof. In some embodiments, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure comprises a mutation selected from the group consisting of 568REY570 to 568NET570 (NGLY1), 591LFT593 to 591NFT593 (NGLY2), 608KMSI611 to 608NMSI611 (NGLY3), 608KMSI611 to 608KNST611 (NGLY4), 636RLPR639 to 636NLSR639 (NGLY5), 636RLPR639 to 636RNAS639 (NGLY6), 665YGNL668 to 665NVTL668 (NGLY7), 667NLTRP671 to 667LNVTA671 (NGLY8) and combinations thereof. I.e. the one or more N-linked glycosylation sites are added and / or shifted as compared to wild-type ADAMTS13 by introducing a mutation selected from this group. The indications between brackets such as “NGLY1”, “NGLY2”, etc. refer to the variants indicated in tables 3 and 4. The indications “N-glyx” and “NGLYx” are used herein interchangeably, such as “N-gly1” and “NGLY1” or “N-gly2” and “NGLY2”, etc. In some embodiments, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure comprises a mutation selected from the group consisting of 591LFT593 to 591NFT593 (NGLY2), 608KMSI611 to 608NMSI611 (NGLY3), 608KMSI611 to 608KNST611 (NGLY4), 665YGNL668 to 665NVTL668 (NGLY7) and 667NLTRP671 to 667LNVTA671 (NGLY8), more preferably comprising a mutation selected from the group consisting of 608KMSI611 to 608NMSI611 (NGLY3), 608KMSI611 to 608KNST611 (NGLY4) and 665YGNL668 to 665NVTL668 (NGLY7), most preferably comprising mutation 608KMSI611 to 608NMSI611 (NGLY3). I.e. the one or more N-linked glycosylation sites are added and / or shifted as compared to wild-type ADAMTS13 by introducing a mutation selected from this group. In some embodiments, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure comprising an N-linked glycosylation site at amino acid residue 1251, 1255,1368, or any combination thereof, preferably comprising an N-linked glycosylation site at amino acid residues 1251, 1255, 1368, 1251+1255, 1251+1368, 1255+ 1368, or 1251+1255+1368, of the ADAMTS13 sequence, as shown in figure 1 or as defined by SEQ ID NO: 43, further comprises such one or more N-linked glycosylation sites added to or shifted in the spacer domain as defined herein. In some embodiments, an ADAMTS13 protein variant is a full length ADAMTS13 protein variant, i.e., an ADAMTS13 protein variant having amino acids 1-1427 as shown in figure 1 or as defined by SEQ ID NO: 43, comprising one or more mutations as provided herein. In some embodiments, an ADAMTS protein variant comprises a portion of the full length ADAMTS13 protein variant and comprises one or more mutations as provided herein. In addition to the one or more N-linked glycosylation sites as provided herein, an ADAMTS13 protein variant according to the present disclosure or used in accordance with the present disclosure may comprise a further mutation at one or more amino acid residues. In some embodiments such mutation or mutations do not introduce a glycosylation site in the protein variant. In some embodiments, such mutation or mutations are a mutation or mutations in the amino acid sequence of the protein variant as compared to amino acid sequence of wild-type ADAMTS13 protein. For example, one or more mutations that further reduce binding by autoantibodies to the ADAMTS13 protein variant, one or more mutations that result in an increase in proteolytic activity against VWF, and / or one or more mutations that increase stability of the ADAMTS13 protein variant can be introduced. In some embodiments, a mutation can be a substitution of an amino acid by another amino acid, an insertion of one or more amino acids or a deletion of one or more amino acids. In some embodiments, a mutation or mutations are substitutions of one or more amino acids by another amino acids. In some embodiments, a mutation can be introduced throughout the sequence of the protein variant. In some embodiments, one or more mutations, preferably substitutions, are introduced in the sites within the different domains of ADAMTS13 that are targeted by autoantibodies. In some embodiments, a mutation, e.g., a substitution, is introduced at one or more amino acid residues in the spacer domain comprising residues S556 to A685 as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure comprises a mutation, preferably substitution, at one or more amino acid residues selected from the group consisting of R568, L591, F592, R636, L637, L668, L591, F592, R636, L637, R660, Y661, Y665 and L668. In some embodiments, one or more amino acids that are mutated in the known gain of function mutants, i.e. R568, F592, R660, Y661 and Y665, are mutated in an ADAMTS13 protein variant according to the disclosure, such as R660, Y661 and Y665, or R568, F592, R660 and Y661 or R568, F592, R660, Y661 and Y665. In some embodiments, an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure comprises one or more mutations selected from the group consisting of R568K, R568A, R568N, L591A, F592Y, F592A, F592N, R636A, L637A, R660K, R660A, R660N, Y661F, Y661A,Y661N, Y665F, Y665A, Y665N, and L668A. As shown in e.g. WO 2021 / 242092 and in e.g. Jian et al.2012, Pos et al. 2010 and Graça et al.2019, such mutants either preserve or increase proteolytic activity of ADAMTS13. In some embodiments, an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure comprises mutations R568A and Y665A. In some embodiments, an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure comprises mutations L591A, R636A, L637A, and L668A. In some embodiments, an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure comprises mutations R568A and Y665A or mutations L591A, R636A, L637A, and L668A. In some embodiments, an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure comprises mutations R660K, R660A or R660N; Y661F, Y661A or Y661N; and Y665F, Y665A or Y665N. In some embodiments, an ADAMTS13 protein variant according to the disclosure comprises mutations R568K, R568A or R568N; F592Y, F592A or F592N; R660K, R660A or R660N; and Y661F, Y661A or Y661N. In some embodiments, an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure comprises mutations R568K, R568A or R568N; F592Y, F592A or F592N; R660K, R660A or R660N; Y661F, Y661A or Y661N; and Y665F, Y665A or Y665N. In some embodiments, an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure comprising an N-linked glycosylation site at amino acid residue 1251, 1255 and / or 1368, preferably comprising an N-linked glycosylation site at amino acid residues 1251, 1255, 1368, 1251 and 1255, 1251 and 1368, 1255 and 1368, of the ADAMTS13 sequence, as shown in figure 1 or as defined by SEQ ID NO: 43, further comprises one or more of said further mutations. In some embodiments, a ADAMTS13 protein variant is a full length ADAMTS13 protein variant, i.e. having amino acids 1-1427 as shown in figure 1 or as defined by SEQ ID NO: 43, comprising the mutations as provided herein. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites selected from table 1 and / or table 2. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites selected from table 1. In some embodiments, a N-linked glycosylation sites selected from table 1 is 1251N, 1255N and / or 1368N, more preferably 1251N, 1255N, 1251N+1255N, 1368N, 1251N+1368N and / or 1255+1368N. In some embodiments, an ADAMTS13 protein variant comprises one or more, preferably one to five, more preferably one or two, N-linked glycosylation sites selected from table 1 and / or table 2, and one or more N-linked glycosylation sites selected from table 3. In some embodiments, an ADAMTS13 protein variant comprises one or more, preferably one to five, more preferably one or two, N-linked glycosylation sites selected from table 1, and one or more N-linked glycosylation sites selected from table 3. In some embodiments, a N-linked glycosylation sites selected from table 1 is 1251N, 1255N and / or 1368N, more preferably 1251N, 1255N, 1251N+1255N, 1368N, 1251N+1368N and / or 1255+1368N. In some embodiments said N-linked glycosylation sites selected from table 3 is NGLY3, NGLY7 and / or NGLY8, more preferably NGLY3 or NGLY3 and NGLY7. In some embodiments, an ADAMTS13 protein variant comprises one or more, such as one to five, such as one or two, N-linked glycosylation sites selected from table 1 and / or table 2, optionally one or more N-linked glycosylation sites selected from table 3 and mutations R568A / F592A / R660A / Y661A / Y665A. In some embodiments, an ADAMTS13 protein variant comprises one or more, preferably one to five, more preferably one or two, N-linked glycosylation sites selected from table 1, optionally one or more N-linked glycosylation sites selected from table 3 and mutations R568A / F592A / R660A / Y661A / Y665A. In some embodiments, a N- linked glycosylation sites selected from table 1 is 1251N, 1255N and / or 1368N, more preferably 1251N, 1255N, 1251N+1255N, 1368N, 1251N+1368N and / or 1255+1368N. In some embodiments, a N-linked glycosylation sites selected from table 3 is NGLY3, NGLY7 and / or NGLY8, more preferably NGLY3 or NGLY3 and NGLY7. In some embodiments, an ADAMTS13 protein variant of the disclosure or used in accordance with the disclosure is selected from table 4. In some embodiments, an ADAMTS13 protein variant comprises amino acids 75 to 1427 of the ADAMTS13 amino acid sequence as shown in figure 1 (as defined by SEQ ID NO: 43) or is a full length ADAMTS13 protein variant as defined by SEQ ID NO: 43, but comprising one or more N-linked glycosylation sites in part of the CUB domain, and optionally additional mutations, preferably as described herein. Table 1. Exemplary N-linked glycosylation sites in the ADAMTS13 CUB domain. Mutant Original Sequence Mutated Sequence 1251N 1250-WRKMC-1254 1250-WNKTC-1254 1255N 1254-CRKLL-1258 1254-CNKTL-1258 1295N 1294-TFYRE-1298 1294-TNYTE-1298 1368N 1367-RTTAF-1371 1367-RNTTF-1371 Table 2. Exemplary N-linked glycosylation sites in the ADAMTS13 CUB domain. Mutant Original Sequence Mutated Sequence 1248N 1247-RLTWR-1251 1247-RNTTR-1251 1249N 1248-LTWRK-1252 1248-LNWTR-1253 1250N 1249-TWRKM-1253 1249-TNRTM-1253 1274N 1276-QRCGR-1280 1276-QNCTR-1280 1326N 1325-CRLFI-1329 1325-CNLTI-1329 1364N 1363-THSLR-1367 1363-TNSTR-1367 1365N 1364-HSLRT-1368 1364-HNLTT-1368 1366N 1365-SLRTT-1369 1365-SNRTT-1369 1392N 1391-SEGFL-1395 1391-SNGTL-1395 Table 3: Exemplary N-linked glycosylation sites in the ADAMTS13 spacer domain Mutation Original sequence Mutated sequence NGLY1 567-AREYV-571 567-ANETV-571 NGLY2 590-PLFTH-594 590-PNFTH-594 NGLY3 607-GKMSI-611 607-GNMSI-611 NGLY4 608-KMSIS-612 608-KNSTS-612 NGLY5 635-DRLPR-639 635-DNLSR-639 NGLY6 636-RLPRL-640 636-RNASL-640 NGLY7 664-EYGNLT-669 664-ENVTLT-669 (glycan shift from N667 to Y665) NGLY8 667-NLTRP-671 667-LNVTA-671 Glycan shift from N667 to L668) NGLY3 + 607-GKMSI-611 / 607-GNMSI-611 / NGLY7 664-EYGNLT-669 664-ENVTLT-669 NGLY3+ 607-GKMSI-611 / 607-GNMSI-611 / NGLY8 667-NLTRP-671 667-LNVTA-671 Table 4. Exemplary ADAMTS13 N-linked glycosylation variants of the disclosure. Mutation Original sequence Mutated sequence 1251N 1250-WRKMC-1254 1250-WNKTC-1254 1255N 1254-CRKLL-1258 1254-CNKTL-1258 1295N 1294-TFYRE-1298 1294-TNYTE-1298 1368N 1367-RTTAF-1371 1367-RNTTF-1371 1250-WRKMC-1254 / 1367-RNTTF-1371 / 1251N+1368N 1367-RTTAF-1371 1367-RNTTF-1371 1254-CRKLL-1258 / 1254-CNKTL-1258 / 1255N+1368N 1367-RTTAF-1371 1367-RNTTF-1371 5ALA+1251N R568 / F592 / R660 / Y661 / A568 / A592 / A660 / A661 Y665 / 1250-WRKMC- / A665 / 1254 1250-WNKTC-1254 5ALA+1368N R568 / F592 / R660 / Y661 / A568 / A592 / A660 / A661 Y665 / / A665 / 1367-RTTAF-1371 1367-RNTTF-1371 5ALA+1251N+ R568 / F592 / R660 / Y661 / A568 / A592 / A660 / A661 1368N Y665 / / A665 / 1250-WRKMC-1254 / 1250-WNKTC-1254 / 1367-RTTAF-1371 1367-RNTTF-1371 5ALA+1255N+ R568 / F592 / R660 / Y661 / A568 / A592 / A660 / A661 1368N Y665 / / A665 / 1254-CRKLL-1258 / 1254-CNKTL-1258 / 1367-RTTAF-1371 1367-RNTTF-1371 NGLY3+1251N+ 607-GKMSI-611 / 607-GNMSI-611 / 1368N 1250-WRKMC-1254 / 1250-WNKTC-1254 / 1367-RTTAF-1371 1367-RNTTF-1371 NGLY3+1255N+ 607-GKMSI-611 / 607-GNMSI-611 / 1368N 1254-CRKLL-1258 / 1254-CNKTL-1258 / 1367-RTTAF-1371 1367-RNTTF-1371 NGLY3+NGLY7+ 607-GKMSI-611 / 664- 607-GNMSI-611 / 1251N+1368N EYGNLT-669 / 1250- 664-ENVTLT-669 / WRKMC-1254 / 1367- 1250-WNKTC-1254 / RTTAF-1371 1367-RNTTF-1371 NGLY3+NGLY7+ 607-GKMSI-611 / 664- 607-GNMSI-611 / 1255N+1368N EYGNLT-669 / 1254- 664-ENVTLT-669 / CRKLL-1258 / 1367- 1254-CNKTL-1258 / RTTAF-1371 1367-RNTTF-1371 In some embodiments, an ADAMTS13 protein variant of the disclosure does not comprise an N-linked glycosylation site that is not present in wild-type ADAMTS13 other than the N-linked glycosylation sites defined herein. In some embodiments, an ADAMTS13 protein variant of the disclosure further comprises one or two of the N-linked glycosylation sites as defined herein. The disclosure further provides an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure comprising a N-linked glycan at the one or more N-linked glycosylation sites as defined herein. In some embodiments, an ADAMTS13 protein variant comprises amino acids 75 to 1427 of the ADAMTS13 amino acid sequence as shown in figure 1 (as defined by SEQ ID NO: 43) or is a full length ADAMTS13 protein variant or as defined by SEQ ID NO: 43, but comprising one or more N-linked glycosylation sites in part of the CUB domain, and optionally additional mutations, preferably as described herein. As used herein, the term “N-linked glycan“ refers to a carbohydrate moiety that is linked to a protein or protein variant via a nitrogen linkage at an N- glycosylation site. As detailed herein above, a variety of N-linked glycans exists and the N-linked glycan can be any glycan that can be attached to an N-linked glycosylation site as defined herein. A person skilled in the art is well aware of glycan that can be attached to N-linked glycosylation sites. Figure 2 shows suitable common and other structures of N-linked glycans. In some embodiment, a N-linked glycan is an N-linked glycan selected from the N-linked glycans shown in figure 2. Attachment of N-linked glycans to an ADAMTS13 protein variant as described herein can be achieved by methods known in the art, including recombinantly producing the protein variant in a suitable host cell, that is capable of producing glycoproteins containing N-linked glycans. Suitable host cells include eukaryotic host cells, in particular mammalian cell, such as CHO cells, NS0 cells, SP2 / 0 cells, PERC.6 cells or HEK293 cells. Alternatively, in vitro modification of the glycosylation patterns is possible. The disclosure also provides a nucleic acid encoding an ADAMTS13 protein variant according to the disclosure. Further provided is a nucleic acid construct comprising a nucleic acid sequence encoding an ADAMTS13 protein variant according to the disclosure. Nucleic acid sequences and constructs according to the disclosure are useful for therapeutic application as well as in the preparation of the ADAMTS13 protein variants according to the disclosure. In some embodiments, a nucleic acid encodes amino acids 75 to 1427 of the ADAMTS13 amino acid sequence as shown in figure 1 (as defined by SEQ ID NO: 43) or encodes a full length ADAMTS13 protein variant as defined by SEQ ID NO: 43, but comprising one or more N-linked glycosylation sites in part of the CUB domain, and optionally additional mutations, preferably as described herein. The term “nucleic acid”, as used herein, refers to DNA and RNA including mRNA or cDNA, as well as synthetic variants thereof. The nucleic acid can be a recombinant or synthetic nucleic acid. The nucleic acid construct according to the disclosure is preferably present in a vector, such as an expression vector or plasmid. The expression vector can be a viral vector or non-viral vector or plasmid. Non-limiting examples of suitable expression vectors include retroviral, adenoviral, adeno-associated, herpes simplex and lentiviral vectors, non-viral vectors and plasmids and engineered vectors. Non- viral expression vectors and plasmids include nude DNA, and nucleic acids packaged into synthetic or engineered compositions such as liposomes, polymers, nanoparticles and molecular conjugates. Methods for the generation of such non- viral expression vectors are well known in the art. The expression vector preferably comprises a strong promoter / enhancer, such as the CMV or SV40 promoter, an optimal translation initiation sequence, such as a ribosomal binding site and start codon, and / or a transcription termination sequence, including a poly(A) signal when the protein is expressed in eukaryotic cells. A person skilled in the art will understand that the expression vector to be used is dependent on the host cell that is used for expression of an ADAMTS13 protein variant according to the disclosure, preferably a N-linked glycan containing protein variant. An expression vector is preferably suited for expression of a nucleic acid molecule of the disclosure in eukaryotic host cells, more preferably mammalian host cells, more preferably in CHO cells, NS0 cells, SP2 / 0 cells, PERC.6 cells and / or HEK293 cells. As an alternative, a nucleic acid sequence used in accordance with the disclosure may be provided to a subject by gene editing technology, including CRISPR / Cas, zinc-finger nucleases, and transcription activator-like effector nucleases-TALEN, in order to insert the receptor transgenes into specific loci with or without an exogenous promoter. Preferred genomic loci include the AAVS1 locus and the PD-1 locus, as is known to a skilled person. Also provided herein is a pharmaceutical composition comprising an ADAMTS13 protein variant according to the disclosure and one or more pharmaceutically acceptable carriers, adjuvants, excipients and / or diluents. By "pharmaceutically acceptable" it is meant that the auxiliary, carrier, diluent or excipient must be compatible with the other ingredients of the formulation and not deleterious, e.g. toxic, to the recipient thereof. In general, any pharmaceutically suitable additive which does not interfere with the function of the active compounds can be used. A pharmaceutical composition according to the disclosure is preferably suitable for human use. In some embodiments, a pharmaceutical composition according to the disclosure is suitable for or adapted for parenteral administration. In some embodiments, administration is intravenous, intra-arterial, subcutaneous, and / or intramuscular administration. In some embodiments, administration may either be by injection or by infusion. In some embodiments, compositions are solutions comprising the ADAMTS13 protein variant of the disclosure in sterile aqueous solution. In some embodiments, an aqueous solution is an isotonic aqueous buffer, an oily solution, a dispersion, emulsion and / or suspension. In some embodiments, a pharmaceutical composition comprise one or more of a buffer system, a preservative, a tonicity agent, a chelating agent, a stabilizer, a surfactant, a solubilizing agent and combinations thereof. The use of preservatives, isotonic agents, chelating agents, stabilizers and surfactants in pharmaceutical compositions is well-known to the skilled person. Reference may be made to Remington: The Science and Practice of Pharmacy, 19th edition, 1995. The pharmaceutical compositions may include a local anesthetic to ease the pain at the site of the injection or infusion. In some embodiments, a pharmaceutical composition according to the disclosure is liquid pharmaceutical composition. In some embodiments, a pharmaceutical composition is an aqueous composition. Such a composition is typically a solution or a suspension, but also includes colloids, dispersions, emulsions, and multi-phase materials. The term “aqueous composition” is defined herein as a composition comprising at least 50% w / w water. Likewise, the term “aqueous solution” is defined as a solution comprising at least 50% w / w water, and the term “aqueous suspension” is defined as a suspension comprising at least 50% w / w water. In some preferred embodiments, the composition is a sterile aqueous solution such as an isotonic aqueous buffer. In some embodiments, a pharmaceutical composition according to the disclosure is a solid composition, in particular a freeze-dried composition. Such solid, in particular freeze-dried, composition can for instance be reconstituted to a liquid composition prior to administration to a subject. In particular, a solvent and / or a diluent may be added to such composition prior to use. It is within the ability of a person skilled in the art to determine an appropriate dosing regimen, i.e. dosage and administration interval, depending on the condition to be treated and the desired effect (e.g. short-lived effect or long term treatment). The exact dose and regimen of these compounds and compositions thereof will further be dependent on the biological activity of the ADAMTS13 protein variant, the age, weight and sex of the subject, the needs of the individual subject to whom the medicament is administered, the degree of affliction or need and the judgment of the medical practitioner. An example of a suitable dose is for instance a dose ranging from 0.1 mg to 15 gram, such as from 1 to 10 gram, of the ADAMTS13 protein variant of the disclosure. In some embodiments, the pharmaceutical composition comprises an aqueous solution of an ADAMTS13 protein variant according to the disclosure, and a buffer, wherein the ADAMTS13 protein variant is present in a concentration of 1 mg / ml or above, and wherein said composition has a pH from about 5.0 to about 8.0. In further embodiments, the pharmaceutical composition comprises an aqueous solution of an ADAMTS13 protein variant according to the disclosure, and a buffer, wherein the ADAMTS13 protein variant is present in a concentration of 1 mg / ml to 150 mg / ml, and wherein said composition has a pH from about 5.0 to about 8.0. In some embodiments, a pharmaceutical kit or kit of parts is provided comprising one or more containers filled with one or more pharmaceutical compositions of the disclosure. Associated with such container(s) can be various written materials such as instructions for use, or a notice in the form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceuticals products, which notice reflects approval by the agency of manufacture, use, or sale for human or veterinary administration. Preferably, a pharmaceutical kit or kit of parts comprises instructions for use. In some embodiments, an ADAMTS13 protein variants used in accordance with the disclosure can be administered to a subject by a variety of routes. For example, the ADAMTS13 protein variant can be administered by suitable parenteral or nonparenteral route, including, for example, topically (e.g., cream, ointment, eyedrops), or nasally (e.g., solution, suspension). Parenteral administration can include, for example, intraarticular, intramuscular, intravenous, intraventricular, intraarterial, intrathecal, subcutaneous, or intraperitoneal administration. Intravenous and subcutaneous administration may be most advantageous. In some embodiments, an ADAMTS13 protein variant may be administered to a subject in hospital via infusion or via injection by a healthcare professional. In some embodiments, an ADAMTS13 protein variant according to the disclosure can be prepared by methods generally known and available in the art. For instance, the person skilled in the art will understand how to generate a DNA sequence that encodes an amino acid sequence of a protein variant according to the disclosure and how to prepare and isolate a nucleic acid molecule with said DNA sequence using generally known recombinant DNA techniques. Introducing, adding or shifting an N-linked glycosylation site can be achieved by introducing one or more mutations in the amino acid sequence as compared to wild-type ADAMTS13 such that an N-linked glycosylation site is shifted. Such mutations can be one or more substitutions of an amino acid residue by another amino acid residue, insertion of one or more amino acid residues or deletion of one or more amino acid residues, or a combination thereof, in such a way that the location of an N-linked glycosylation site is introduced, added or shifted as compared to the location of an N-linked glycosylation site in the wild-type ADAMTS13 sequence. In a preferred embodiment, an N-linked glycosylation site is introduced, added or shifted by one or more substitutions of an amino acid residue with another amino acid residue. In particular any amino acid can be substituted with an asparagine residue to introduce an asparagine as the first residue in the N-linked glycosylation site NXS or NXT as defined herein, a proline can be substituted with any other amino acid to remove a potential proline as the second residue in the N-linked glycosylation site NXS or NXT as defined herein, any amino acid other than serine and threonine can be substituted with serine or threonine to introduce a serine or threonine as the third residue in the N-linked glycosylation site NXS or NXT as defined herein, or a combination thereof. Alternatively or in addition, an asparagine can be substituted by any other amino acid to remove an N-linked glycosylation site that is present in wild-type ADAMTS13. The sequence of the nucleic acid molecule can be codon-optimized for expression in a suitable host cell. Nucleic acid molecules can be introduced in an expression vector as described herein above using recombinant DNA techniques known by the person skilled in the art. Expression vectors in the context of the disclosure direct the expression of a protein variant according to the disclosure in a suitable host cell as described herein. As an alternative, a nucleic acid molecule may be inserted in the genome of a host cell, using suitable gene editing technology as described herein. Said insertion preferably is at a locus or within a region that ensures expression of a nucleic acid molecule of the disclosure in the host cell. The term “host cell” as used herein refers to any cell capable of expressing a heterologous protein, polypeptide or peptide. In a preferred embodiment, the host cell is capable of attaching N-linked glycans to protein, peptide or polypeptide. In a further preferred embodiment, the host cell is an eukaryotic host cell, more preferably a mammalian cell, more preferably selected from the group consisting of CHO cells, NS0 cells, SP2 / 0 cells, PERC.6 cells and HEK293 cells. Suitable transfection techniques are known in the art, e.g., from Green & Sambrook., 2012. “Molecular Cloning: A Laboratory Manual”, 4thEdition, CSHL Press; Cold Spring Harbor Protocols, www.cshprotocols.cshlp.org). In some embodiments, ADAMTS13 protein variants according to the disclosure are less susceptible to binding by anti-CUB domain autoantibodies as compared to wild-type ADAMTS13 and known ADAMTS13 protein variants. In one aspect, the disclosure therefore provides a method for reducing autoantibody binding, in particular binding by anti-CUB domain antibodies, to ADAMTS13 or a variant thereof said method comprising introducing into the ADAMTS13 or variant one or more, preferably one or two, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326- 1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, thereby reducing autoantibody-binding to the ADAMTS13 or variant. As detailed herein above, anti-CUB domain autoantibodies upon binding to ADAMTS13 are believed to enhance plasma clearance thereof. In some aspects, the disclosure therefore provides a method for reducing plasma clearance, in particular antibody-mediated plasma clearance, of ADAMTS13 or a variant thereof, said method comprising introducing into the ADAMTS13 or variant one or more, preferably one or two, N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, thereby reducing plasma clearance, in particular antibody-mediated plasma clearance, of the ADAMTS13 or variant. I.e. said one or more N-linked glycosylation sites are present at amino acid residues 1246, 1247, 1248, 1249, 1250, 1251, 1252, 1253, 1254, 1255, 1256, 1257, 1258, 1272, 1273, 1274, 1275, 1276, 1295, 1296, 1297, 1326, 1327, 1328, 1361, 1362, 1363, 1364, 1365, 1366, 1367, 1368, 1369, 1370, 1392, 1393 and / or 1394 as indicated in figure 1 or in SEQ ID NO: 43. As used herein, the term “plasma clearance” refers to the rate at which a ADAMTS13 or a variant thereof is removed from blood, e.g. after administration of thereof to a subject. In some embodiments, an ADAMTS13 protein variant in which the one or more N-linked glycosylation sites are introduced is wild-type ADAMTS13. In some embodiments, an ADAMTS13 in which the one or more N-linked glycosylation sites are introduced is an ADAMTS13 protein variant. In some embodiments, an ADAMTS protein variant is an ADAMTS13 protein variant with reduced binding to auto-antibodies specific for the spacer domain as compared to wild-type ADAMTS13, e.g., as defined herein wherein further one or more N-linked glycosylation sites are added as compared to wild-type ADAMTS13 and / or one or more existing N-linked glycosylation sites are shifted as compared to wild-type ADAMTS13 in a spacer domain comprising amino acid residues S556 to A685 of ADAMTS13 as shown in figure 1 (as defined by SEQ ID NO: 43) and / or one or more mutations at one or more amino acid residues is in the spacer domain comprising residues 556 to 685 of ADAMTS13 as shown in figure 1 or as defined by SEQ ID NO: 43. In some embodiments, a N-linked glycosylation site are added and / or shifted at amino acid residue 568, 591, 608, 609, 636, 637, 665 and / or 668, preferably at amino acid residue 608, 609 and / or 665, and / or comprising a mutation at an amino acid residue selected from the group consisting of R568, L591, F592, R636, L637, L668, L591, F592, R636, L637, R660, Y661, Y665. Hence, in some aspects, the resulting ADAMTS13 protein variant with reduced autoantibody binding and / or reduced (autoantibody-mediated) plasma clearance as compared to wild-type ADAMTS13 is an ADAMTS13 protein variant according to the disclosure or used in accordance with the disclosure wherein further one or more N-linked glycosylation sites are added as compared to wild- type ADAMTS13 and / or one or more existing N-linked glycosylation sites are shifted as compared to wild-type ADAMTS13 in a spacer domain comprising amino acid residues S556 to A685 of ADAMTS13 as shown in figure 1 (as defined by SEQ ID NO: 43) and / or comprising a further mutation at one or more amino acid residues in the spacer domain comprising residues 556 to 685 of ADAMTS13 as shown in figure 1 or SEQ ID NO: 43 as defined herein. In some embodiments, ADAMTS13 protein variants provided herein have VWF proteolytic activity and are therefore particularly useful for treating disorders characterized by aberrant VWF activity and / or VWF processing and / or a thrombotic disease. The disclosure provides an ADAMTS13 protein variant according to the disclosure for use in therapy. Also provided is such ADAMTS13 protein variant or nucleic acid construct encoding such ADAMTS13 protein variant for use as an antithrombotic agent. As used herein, the term “antithrombotic agent” refers to a compound that prevents the formation of blood clots, reduces or slows down the formation of blood clots and / or counteracts, reduces impact of or degrades existing blood clots. The disclosure also provides an ADAMTS13 protein variant according to the disclosure or nucleic acid construct encoding such ADAMTS13 protein variant according to the disclosure for use in the treatment of a disorder characterized by aberrant Von Willebrand Factor (VWF) activity and / or VWF processing. Also provided is a method for the treatment of a disorder characterized by aberrant Von Willebrand Factor (VWF) activity and / or VWF processing comprising administering to a subject in need thereof an ADAMTS13 protein variant according to the disclosure or nucleic acid construct encoding such ADAMTS13 protein variant according to the disclosure. In some embodiments, ADAMTS13 protein variants of the disclosure show reduced binding by anti-CUB domain autoantibodies as compared to wild-type ADAMTS13. In some embodiments, such reduced autoantibody binding results in reduced anti-CUB autoantibody-mediated ADAMTS-13 clearance. In some embodiments, a subject that is treated in accordance with the present disclosure is therefore characterized by autoantibodies against the ADAMTS13 CUB domain. In some embodiments, a subject that is treated in accordance with the present disclosure is further characterized by autoantibodies against the ADAMTS13 spacer domain. In some embodiments, a subject that is treated in accordance with the present disclosure is characterized by autoantibodies against the spacer domain and the CUB domain. In some embodiments, a subject is a subject suffering from iTTP. As described in the Examples herein, not all patients, in particular iTTP patients, having autoantibodies against the spacer domain are expected to be sufficiently susceptible to treatment with ADAMTS13 protein variants that reduce autoantibody binding to this domain, e.g. to treatment with an ADAMTS13 protein variant comprising an N-linked glycosylation site at amino acids residue 608 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, in particular comprising mutation 607-GKMSI-611 to 607-GNMSI-611 (herein also referred to as the NGLY3 variant). Now that the present inventors have identified ADAMTS13 protein variants that reduced binding of autoantibodies to the CUB domain and variants that reduce binding to autoantibodies to both the spacer domain and the CUB domain, it has become possible to treat such patients as well. Also provided is therefore an ADAMTS13 protein variant according to the disclosure or a nucleic acid construct according to the disclosure for use in the treatment of a disorder characterized by aberrant Von Willebrand Factor (VWF) activity and / or VWF processing in a patient that inadequately responds to treatment that reduces ADAMTS13 autoantibody binding to the spacer domain. Also provided is a method of treatment of a disorder characterized by aberrant Von Willebrand Factor (VWF) activity and / or VWF processing in a patient that inadequately responds to treatment that reduces ADAMTS13 autoantibody binding to the spacer domain comprising administering to the patient a therapeutically effective amount of an ADAMTS13 protein variant according to the disclosure. In some embodiments, a treatment that reduces ADAMTS13 autoantibody binding to the spacer domain is treatment with an ADAMTS13 protein variant comprising an N-linked glycosylation site at amino acids residue 608 of the ADAMTS13 sequence as shown in figure 1 or as defined by SEQ ID NO: 43, in particular comprising mutation 607-GKMSI-611 to 607-GNMSI-611 (herein also referred to as the NGLY3 variant). In some embodiments, a patient is a TPP patient, such as an iTTP patient. As used herein “inadequately responds” refers in general to an inadequate efficacy of such treatment. In particular, it means that the response to treatment is not sufficient to achieve a meaningful clinical result, as evidenced by e.g. a reduction in autoantibody binding that is insufficient and / or proteolytic activity against VWF that is insufficient. In general, a proteolytic activity against VWF that is below 30% of the activity of wild-type ADAMTS13, in particular in the absence of autoantibodies, is considered insufficient. As used herein, “a proteolytic activity against VWF that is insufficient” therefore refers to a proteolytic activity against VWF that is below 30%,of the activity of wild-type ADAMTS13, in particular in the absence of autoantibodies, preferably below 25%, more preferably below 20%, more preferably below 15%, more preferably below 10% of proteolytic activity of wild-type ADAMTS13. Such proteolytic activity can be determined as described herein above, e.g. in an in vitro assay with FRETS-VWF73 or VWF multimer assay. In some embodiments, an inadequate response to treatment that reduces ADAMTS13 autoantibody binding to the spacer domain can be assessed after a patient has been treated with treatment that reduces ADAMTS13 autoantibody binding to the spacer domain by assessing treatment outcomes. In some embodiments, an inadequate response to treatment that reduces ADAMTS13 autoantibody binding to the spacer domain can be assessed prior to treatment based on the autoantibody profile of a patient, i.e. by determining whether or not a subject has autoantibodies against ADAMTS13 and, if so, which domain or domains of ADAMTS13 are targeted by these autoantibodies. Based thereon, it can be assessed whether a patient is likely to have an inadequate response to treatment that reduces ADAMTS13 autoantibody binding to the spacer domain. Whether or not a subject has autoantibodies against ADAMTS13 and, if so, which domain or domains of ADAMTS13 are targeted by these autoantibodies can be determined using samples of the subject, e.g. plasma and / or serum samples. This can for instance be performed using an assay, including e.g. an ELISA assay, wherein the epitope that is bound by autoantibodies present in the sample is determined. E.g. an assay can be used in which ADAMTS13 is immobilized e.g. on a plate, such as maxisorb plate, and incubated with patient plasma sample. After washing, bound autoantibodies can be detected using labeled anti-human IgG antibodies. A suitable method is described in Thomas et al. 2015, which is incorporated by herein by reference. ADAMTS13 and variants thereof can also be immobilized by coating a plate, such as a maxisorb plate with a monoclonal antibody directed towards the protease domain of ADAMTS13. Following incubation with patient samples, bound anti-ADAMTS13 antibody can be detected using labelled anti-human Ig antibodies. A suitable method is described in Postmus et al. 2023. As used herein, the term “von Willebrand Factor” or “VWF” refers to a plasma glycoprotein that mediates adhesion and aggregation of platelets. VWF is synthesized by endothelial cells and megakaryocytes as long multimers with a molecular weight of up to more than 20,000 kDa. The majority of circulating VWF is synthesized by endothelial cells. Most of the secreted VWF consists of ultra-large VWF (ULVWF) multimers that are prothrombotic. As described herein above, prothrombotic activity of VWF is regulated during normal hemostasis through limited cleavage by ADAMTS13. As used herein “aberrant VWF activity” means that activity VWF activity, in particular prothrombotic activity of VWF, deviates from VWF activity in healthy subjects, preferably is increased as compared to VWF activity in healthy subjects. The deviation or increase is in particular such that it results in adverse health effect, i.e. in a disease or disorder. “Aberrant VWF processing” as used herein means that processing of VWF, in particular cleavage of VWF, in particular of VWF multimer, deviates from VWF processing in healthy subject, in particular is decreased as compared to VWF processing in healthy subjects. As will be appreciated by the skilled person, the ADAMTS13 protein variants can be used to correct ADAMTS13 deficiency in a subject. Hence, in principle any disorder in which VWF activity or processing is aberrant can be treated with an ADAMTS13 protein variant according to the disclosure. The term “ADAMTS13 deficiency”, as used herein, refers to ADAMTS13 not exhibiting its role in hemostasis (controlling VWF multimer size through cleavage) as in healthy subjects. This could be caused by low ADAMTS13 protein levels, an excess of its substrate VWF or the presence of autoantibodies against ADAMTS13. Preferably, ADAMTS13 deficiency resulting from the presence of autoantibodies in a subject. In some embodiments, provided is an ADAMTS13 protein variant according to the disclosure or nucleic acid construct encoding such ADAMTS13 protein variant according to the disclosure for use in the treatment of a thrombotic disease, both acquired or congenital thrombotic disease. Also provided is a method for the treatment of a thrombotic disease, both acquired or congenital thrombotic disease, comprising administering to a subject in need thereof an ADAMTS13 protein variant according to the disclosure or nucleic acid construct encoding such ADAMTS13 protein variant according to the disclosure. Because such ADAMTS13 protein variant is capable of cleaving and thereby reducing activity of VWF, prothrombotic activity of VWF is reduced. In some embodiments, a disorder is a thrombotic microangiopathy. In some embodiments, a disorder is selected from the group consisting of thrombotic thrombocytopenic purpura (TTP), hemolytic–uremic syndrome (HUS), ischemic stroke, systemic thrombosis, COVID19, antiphospholipid syndrome, pre- eclampsia / HELLP syndrome, sepsis and sickle cell disease. ADAMTS13 is known to have systemic antithrombotic effects, as described for instance by Chauhan et al. (J Exp Med. 2006 Mar 20;203(3):767-76), which showed spontaneous thrombus formation in Adamts13− / −mice and conclude that ADAMTS13 has a powerful natural antithrombotic activity and recombinant ADAMTS13 could be used as an antithrombotic agent. An ADAMTS13 protein variant according to the disclosure can thus be advantageously used in the treatment of systemic thrombosis. Thrombotic microangiopathy includes thrombotic thrombocytopenic purpura (TTP). TTP includes both immune-mediated TTP (iTTP) and congenital TTP (cTTP). In preferred embodiments, the thrombotic microangiopathy is TTP. In further preferred embodiments the disorder is iTTP. Both in iTTP and congenital TTP ADAMTS13 levels are strongly reduced. Recombinant wild-type ADAMTS13 has been approved for treatment of both cTTP and iTTP (Scully et al, N Engl J Med.2019 Jan 24;380(4):335-). An ADAMTS13 protein variant according to the disclosure can thus be used for treatment of both iTTP and congenital TTP. Autoantibodies present in patients with iTTP limit the effectiveness of treatment with wild-type ADAMTS13 as present in human plasma or as produced as a wild- type recombinant ADAMTS13 protein in eukaryotic expression systems. Autoantibody-resistant ADAMTS13 protein variants allow for immediately restoring functional ADAMTS13 levels thereby alleviating the severe thrombotic complications observed in patients with iTTP as well as other thrombotic disorders. HUS is characterized by hemolytic anemia, thrombocytopenia, systemic thrombotic microangiopathy (TMA) and renal failure. Partial ADAMTS13 deficiency can be found in HUS patients. An ADAMTS13 protein variant according to the disclosure can thus be advantageously used in the treatment of HUS, in particular HUS associated with partial ADAMTS13 deficiency. Thrombosis is the predominant underlying mechanism of acute ischemic stroke (AIS). Several studies have found that ADAMTS13 levels are significantly decreased in patient suffering from ischemic stroke, with the lowest levels of ADAMTS13 found in patients suffering from acute stroke. As detailed in a review by Chen et al. (Front Neurol.2019 Jul 17;10:772), the available evidence indicates that ADAMTS13 is closely related to the occurrence, development, and prognosis of ischemic stroke, protecting the brain from ischemia-reperfusion injury. The VWF:ADAMTS13 ratio has a strong correlation with the risk of stroke. The activity and levels of ADAMTS13 have a good predictive value for the occurrence and prognosis of ischemic stroke. In addition, animal studies on ADAMTS13 in the treatment of AIS have made remarkable progress: injections of recombinant ADAMTS13 to wild-type mice 7 days after stroke onset increased the formation of neovasculature and repair of blood vessels, and significantly improved the 14-day prognosis after stroke. It is concluded that ADAMTS13 is expected to become a new therapeutic agent for ischemic stroke. An ADAMTS13 protein variant according to the disclosure can thus be advantageously used in the treatment of ischemic stroke. Sepsis is a disease in which coagulopathy is observed, and thrombotic microangiopathy may be a component thereof. Thrombotic microangiopathy in sepsis is associated with low levels of ADAMTS-13. Ramsi and Al Ali (2018) describe a case of thrombocytopenia-associated multiple-organ failure (TAMOF) associated with sepsis that had dramatic improvement with plasma exchange through which ADAMTS13 activity was restored, and the pathological process and organ failures were halted. An ADAMTS13 protein variant according to the disclosure can thus be advantageously used in the treatment of sepsis, in particular thrombotic microangiopathy in subjects suffering from sepsis. In Sickle cell disease a low ADAMTS13 / VWF ratio has been found and ADAMTS13 activity was lower in patients who developed acute chest syndrome, suggesting quantitative decrease in ADAMTS-13 levels and that administration of recombinant ADAMTS-13 may have a beneficial effect (Sins et al.2017). This indicates that ADAMTS13 protein variants according to the disclosure can thus be advantageously used in the treatment of sickle cell disease. Thrombosis affecting the pulmonary and systemic vasculature is common during severe COVID19 (coronavirus disease 2019), caused by infection with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), Turecek et al. (2021) showed that markedly increased plasma VWF levels were accompanied by a partial reduction in the VWF regulatory protease ADAMTS13. Incubation of plasma samples from patients with severe COVID-19 with recombinant ADAMTS13 (rADAMTS13) substantially reduced the abnormally high VWF activity, reduced overall multimer size and depleted UHMW VWF multimers in a time and concentration dependent manner and it is suggested that rADAMTS13 may have a therapeutic role in helping restore haemostatic balance in COVID-19 patients. This indicates that ADAMTS13 protein variants according to the disclosure can thus be advantageously used in the treatment of COVID-19 and / or SARS-CoV-2 infection. Antiphospholipid syndrome and pre-eclampsia (PEcl) have been associated with reduced ADAMTS13 levels and with higher ADAMTS13 antibodies, and lower ADAMTS13 activity and activity:antigen ratios (Bitsadze et al.2021). Further, thrombocytopenia and microangiopathic hemolytic anemia (TMA) are seen in HELLP syndrome. Additionally, Austin et al. (2008) shows that ADAMTS13 autoantibodies and ADAMTS13 dysfunction can occur in antiphospholipid syndrome. This indicates that ADAMTS13 protein variants according to the disclosure can thus be advantageously used in the treatment of antiphospholipid syndrome and pre-eclampsia / HELLP syndrome, in particular in antiphospholipid syndrome and pre-eclampsia / HELLP syndrome associated with ADAMTS13 dysfunction. Features may be described herein as part of the same or separate aspects or embodiments of the present disclosure for the purpose of clarity and a concise description. It will be appreciated by the skilled person that the scope of the disclosure may include embodiments having combinations of all or some of the features described herein as part of the same or separate embodiments. The disclosure will be explained in more detail in the following, non-limiting examples. Brief description of the drawings Figure 1: Amino acid sequence of ADAMTS13; UniProt accession number Q76LX8. Corresponds to SEQ ID NO: 43. Figure 2: N-linked glycans identified on ADAMTS13 (modified from Verbij et al. 2016). Square :GlcNAc; circle: mannose; circle with interior cross : galactose; triangle: fucose; diamond: sialic acid. Figure 3: Overview of CUB-NGLY variants. A) Table of mutated amino acids for each of the individual CUB N-glycan variants. B) Visualized positions of each of the individual CUB N-glycan mutations on the crystal structure of the CUB domains of ADAMTS13 (PDB: 7B01). Figure 4: N-glycan analysis of CUB-NGLY variants. List of identified deglycosylated peptides after PNGaseF treatment and digestion using either chymotrypsin or thermolysin. Values describe observed signal intensities as identified using PEAKS. -10LgP gives a confidence score of the identified peptide. Start and end indicate the location of the identified peptide within the sequence of ADAMTS13. Figure 5: Activity of CUB-NGLY variants in FRETS-VWF73 activity assay. All mutants were able to efficiently process the FRETS-VWF73 substrate. 1251N+1368N displayed a two-fold increase in activity compared to wild-type ADAMTS13 (WT Ctrl). Figure 6: Activity of CUB-NGLY variants towards VWF multimers. All CUB-NGLY variants were able to digest high molecular weight VWF multimers with equal efficiency as wild-type ADAMTS13 (WT Ctrl). Figure 7: Characterization of patient derived monoclonal anti-CUB antibodies. A) Epitope mapping of the produced antibodies. All antibodies strongly bind to ADAMTS13. None of the antibodies bind the MDTCS variant, indicating that all antibodies target the C-terminal domains of ADAMTS13. B) Activity of wild-type ADAMTS13 in the presence of anti-CUB antibodies and one anti-spacer antibody (1-416). None of the anti-CUB antibodies are able to inhibit ADAMTS13 activity. 1-440 is able to significantly increase ADAMTS13 activity. The spacer antibody (1-416) is able to completely inhibit ADAMTS13, indicating that used concentrations would be sufficient for inhibition. Figure 8: Heatmaps displaying the relative reactivity (binding) of human monoclonal patient derived antibodies to CUB-NGLY, based on two alternative calculation methods. A) Data is based on the Optical Density (OD) binding data. B) A calibration curve based on human monoclonal anti-ADAMTS13 antibody II-1 was used to calculate the binding data. A) and B) Binding to wild-type ADAMTS13 (WT) is set at 100% of binding. A spacer antibody (1-416) is used as a loading control. Combination of 1251N or 1255N with 1368N is able to prevent binding of 6 / 7 anti-CUB antibodies. Figure 9: Reactivity of patient samples to CUB-NGLY variants of ADAMTS13. A) and D) Heatmaps displaying the relative reactivity 9 patient samples to CUB-NGLY combinations. Binding to wild-type ADAMTS13 (WT) is set at 100% of binding. Two different alternative calculation methods were used to calculate activity / binding data. NGLY3 and FL-5ALA (5ALA) prevent binding of anti-spacer antibodies so the effect of the CUB-NGLY can be studied independently. Addition of 1251N+1368N or 1255N+1368N to either NGLY3 or 5ALA results in an additional decrease of antibody binding in 8 / 9 patient samples. B) and E) Addition of both 1251N+1368N and 1255N+1368N to either NGLY3 or FL-5ALA (5ALA) results in a significant decrease in antibody binding. C) and F) The effect of addition of either 1251N+1368N or 1255N+1368N to either of the spacer mutants NGLY3 and 5ALA is equivalent. Indicating that modification of the CUB domains has an independent effect from the spacer mutants, showing that a separate antibody epitope is being targeted. Figure 10: Activity of CUB-NGLY variants in FRETS-VWF73 activity assay at pH 6.0 and pH 7.5. All mutants were able to efficiently process the FRETS- VWF73 substrate at both pHs. The activity at pH 7.5 of 1251N, 1255N, 1320N, 1321N and 1322N was decreased compared to activity at pH 6.0, suggesting these variants are in a closed conformation, similar to wild-type ADAMTS13 (WT). In contrast, 1295N, 1368N, 1251N+1368N, and 1255N+1368N showed identical activity at both pH values, suggesting that these CUB-NGLY variants are present in an open, more active conformation at pH 7.5 when compared to wild-type ADAMTS13. Figure 11: Activity of CUB-NGLY variants of cleaving VWF-multimers under flow (over primary Human Umbilical Vein Endothelial Cells (HUVECs). A) The variants 1251N+1368N and 1255N+1368N displayed similar activity when compared to wild-type ADAMTS13 (wtADAMTS13), showing that CUB-NGLY variants do not impair the ability of ADAMTS13 to cleave VWF multimers under flow. B) Representative images of negative control (no ADAMTS13 added) and wild-type ADAMTS13 as well as 1251N+1368N and 1255N+1368N variants at timepoint zero, two, and nine minutes. Figure 12: Western blot of ADAMTS13 variants using HPR conjugated anti- V5 antibody after expression by ExpiCHO cells. A) and B) ADAMTS13 CUB-NGLY variants express at similar levels to wild-type ADAMTS13. Examples Example 1 Design of N-glycan variants of ADAMTS13 Patients with immune Thrombotic Thrombocytopenic Purpura (iTTP) develop autoantibodies against ADAMTS13. In a majority of patients, these antibodies target an immunodominant region in the spacer domain of ADAMTS13 (Cabin et al., 2002; Ercig et al., 2018; Jian et al., 2012; Pos et al., 2010; Wouter Pos et al., 2011). N-glycan introduction within the spacer domain has shown to reduced antibody binding for these patients (Ercig et al., 2021; Postmus et al., 2023). Nevertheless, autoantibody binding was not completely abolished. This is because a smaller, but still considerate amount, of 20-40% of iTTP patient also develop antibodies against other ADAMTS13 domains, specifically the C-terminal CUB1 and CUB2 domains (Kangro et al., 2021; Klaus et al., 2004; Long Zheng et al., 2010; Pos et al., 2010; Thomas et al., 2015). While these antibodies do not directly inhibit ADAMTS13, they can increase clearance rates of ADAMTS13 from plasma thereby lowering functional levels of ADAMTS13 (Thomas et al., 2015). Additionally, these antibodies are able to open the conformation of ADAMTS13, which results in increased accessibility of the immunodominant epitope on the spacer domain (Roose et al., 2020). Under quiescent conditions ADAMTS13 circulates in blood in a closed conformation. Upon binding to its substrate von Willebrand factor ADAMTS13 transitions to an open conformation (South et al., 2014). The conformational status of ADAMTS13 is dependent on pH; at pH 6.0 ADAMTS13 is present in an open conformation whereas at pH 7.5 ADAMTS13 is present in a closed conformation (Joshua et al., 2014; Muia et al., 2013). It has been previously shown that the activity (as measured by conversion of the synthetic peptide substrate FRETS- VWF73) of ADAMTS13 in a closed conformation (at pH 7.5) is lower when compared to its activity in an open conformation at pH 6.0 (Joshua et al., 2014; Muia et al., 2013). The present disclosure provides ADAMTS13 protein variants where N-glycans have been introduced to the residues surrounding the spacer-CUB interface hereby reducing auto-antibody binding while simultaneously minimalize interference with the spacer-CUB interaction. If the N-glycans were to disrupt this interaction, the spacer domain would still be more accessible to anti-spacer antibodies. Based on structures and models of the spacer and CUB domains of ADAMTS13 and their interaction multiple N-glycans have been introduced in the CUB domains of ADAMTS13 (Figure 3A) (Kim et al., 2021). Introduction of the mutation depended on two main criteria. Firstly, the N-glycans were introduced around the modeled spacer-CUB interface, in order to minimize conformational alterations within this part of the protease. Secondly, the amino acid side-chain had to be facing outward in the crystal structure, as mutating an inward facing sidechain could potentially affect protein stability and / or the efficacy of N-glycan attachment. Based on these criteria, a number of locations were selected for the insertion of an N-glycan. On these locations N-glycan attachment consensus sequence (N-X-T) was introduced. All mutations and their locations in the CUB1 or CUB2 domains are displayed in Figures 3A and 3B. Also combination mutants have been designed in which two N- glycans were introduced in the CUB domains at amino acid positions 1251 / 1368 and 1255 / 1368. Example 2: Expression of CUB N-glycan variants All N-glycan variants of ADAMTS13 were expressed in ExpiCHO cells. Full-length wild-type ADAMTS13, a full-length ADAMTS13 protein variant containing 5 alanine substitutions (R568A / F592A / R660A / Y661A / Y665A) (designated as “ADAMTS13-5ALA” and used synonymously with “5ALA” and “FL-5ALA” herein), and a full-length ADAMTS13 protein variant containing an N-glycan insertion at K608 (NGLY3; 608KMSI611 to 608NMSI611) were used as controls. Additional controls included two truncated variants of ADAMTS13 comprising amino acid 1- 685 of the wild-type, and thus lacking the C-terminal domains including the CUB1 and CUB2 domain, where one had the aforementioned 5 alanine mutations (designated as “MDTCS-5ALA” and used herein) and the other did not (designated as “MDTCS” and used herein). All ADAMTS13 constructs were generated without the pro-peptide; the ADAMTS13 signal peptide was replaced with an Immunoglobulin kappa signal peptide to increase ADAMTS13 production. All constructs were generated in the pcDNA3.1+ expression vector containing a C- terminal V5 tag for detection and Twin-Strep-tag for purification. CUB-NGLY variants were constructed as follows: synthetic DNA fragments encoding residues R1094 to T1427 containing the amino acid substitution for the CUB-NGLY of interest were designed and ordered through Azenta. Synthetic fragments were flanked by MreI and XhoI restriction sites, which were used for cloning the synthetic fragment into the full-length wild-type ADAMTS13, the ADAMTS13- 5ALA, and the NGLY3 construct. The resulting plasmids were sequenced in-house to verify the desired mutations and subsequently expressed in ExpiCHO cells as previously described (Postmus et al., 2023). Supernatants were collected 5 days after transfection. Supernatant was collected by centrifugation at 4000g for 30 minutes, after which the supernatant was supplemented with 10 mM benzamidine, aliquoted and stored at -30°C. ADAMTS13 levels were determined by ELISA as previously described (Postmus et al., 2023). ADAMTS13 protein levels ranged from 1.81 to 25 µg / mL. Western blot of ADAMTS13 variants are shown in Figures 12A- B. Table 5: Antigen levels of ADAMTS13 and variants Variant Antigen level (µg / mL) wild-type ADAMTS13 16.92 wild-type ADAMTS13-5ALA (5ALA) 17.00 1251N 11.09 1255N 13.01 1265N 1.81 1295N 7.11 1320N 14.54 1321N 12.63 1322N 14.34 1368N 9.23 1382N 4.75 1251N+1368N 7.11 1255N+1368N 6.52 5ALA+1251N+1368N 4.45 5ALA+1255N+1368N 7.38 NGLY3+1251N+1368N 12.9 NGLY3+1255N+1368N 18.18 Example 3: Identification of N-glycan attachment using mass- spectrometry Mass spectrometry was employed to confirm that introduction of a N-X-T consensus sequence yielded N-glycan attachment. The following CUB-NGLY variants were analyzed 1251N, 1255N, 1295N, 1320N, 1321N, 1322N, 1368N, 1251N+1368N, and 1255N+1368N. Each of these mutants were purified by immunoprecipitation using Strep-Tactin affinity chromatography after which they were treated with PNGaseF or not (as a control). After PNGaseF treatment, the CUB-NGLY variant was digested using either chymotrypsin or thermolysin, depending on which enzyme would yield mass-spectrometry compatible peptides. PNGaseF treatment of the protein would result in the removal of the N-glycans, and with that a deamidation of the asparagine to which the N-glycan was attached. This deamidation results in a +0.98Da mass shift which is detectable by mass- spectrometry. To exclude a false-positive, the same deamidation event in the non- PNGaseF treated samples was analyzed. For each of the single CUB-NGLY as well as the double CUB-NGLY mutants unique deamidation events on the location of interest were observed, indicating that all N-glycans were successfully introduced (Figure 4). In the samples that were not subjected to PNGaseF treatment, no deamidation event on the respective location was detected. Example 4: Activity of exemplary CUB-NGLY variants Activity of exemplary CUB-NGLY variants (ADAMTS13 protein variants comprising one or more mutations in the CUB domain resulting in a N-X-T site) was assessed using the FRETS-VWF73 substrate. A minimal peptide of 73 amino acids from the A2 domain of VWF, including the Y1605-M1606 scissile bind which gets cleaved by ADAMTS13 and following amino acids crucial for binding of VWF and activation of ADAMTS13. Activity of the CUB-NGLY variants was performed as previously described (Postmus et al., 2023). Activity of diluted ADAMTS13 supernatants was performed at a concentration of 1.05 nM of ADAMTS13 protein variant and 4 µM of FRETS-VWF73 substrate in a final volume of 200 µL activity buffer consisting of 20 mM HEPES, 20 mM Bis-Tris, 20 mM Tris-HCl, 25 mM CaCl2, 0.005% Tween20 (pH 6.0). Activity was measured by detecting the 460 nm emission every 30 seconds for 45 minutes. The slope of the initial activity of each mutant was determined. A calibration curve of wild-type ADAMTS13 in a concentration range of 0.13125 – 2.10 nM was used to calculate the activity of the CUB-NGLY variants. Activity of the mutant was then expressed as a percentage of the wild-type ADAMTS13 at 1.05 nM. The results of this are shown in Figure 5. Activity of all CUB-NLGY variants, with the exception of 1251N-1368N, was equal to that of wild-type ADAMTS13. The 1251N-1368N displayed a two-fold increase in activity. Activity of exemplary CUB-NGLY variants was also assessed using full- length VWF multimers as a substrate. This activity assay was performed as described previously (Postmus et al., 2023). Here, 3.8 nM of ADAMTS13 was diluted in 10 mM HEPES, 10 mM Bis-Tris, 10 mM Tris-HCl, 12.5 mM CaCl2, 0.0025% Tween20 (pH 7.5). In parallel, 80 nM of VWF multimers were diluted in the same buffer and supplemented with 3M urea. Both samples were incubated separately at 37°C for 30 minutes. Afterwards, ADAMTS13 was mixed with the VWF multimers in a 1:1 v / v ratio, resulting in a final concentration of 1.9 nM ADAMTS13, 40 nM VWF, and 1.5M urea. Samples were taken after 10 minutes of incubation at 37°C and the reaction was stopped by addition of 4x sample buffer (9.6 M urea, 4% SDS, 0.035 M Tris-base, 25 mM EDTA, 7.5 µM Bromophenol blue). Quenched samples were then incubated for 10 minutes at 56C and loaded into a 1.8% high gelation temperature agarose gel. Uncleaved VWF-multimers were added as a control. All CUB-NGLY variants showed cleavage of high-MW VWF multimers at a similar level as wild-type ADAMTS13 (Figure 6). Example 5: Expression and characterization of iTTP patient derived anti- CUB antibodies In order to investigate the ability of the newly introduced N-glycans to evade antibody binding, 7 iTTP patient derived anti-CUB1 / 2 IgG1 antibodies and 1 anti- spacer IgG1 antibody (1-416) were cloned based on sequences published (Ostertag et Sal., 2016; US 2019 / 0031771 A1)). Synthetic gene fragments for IgG1 heavy and light chain were ordered at Azenta and cloned into pcDNA3.1+ using HindIII and NotI. Additionally, variable domain gene fragments of both the heavy and light chain for each of the different antibodies were designed and ordered based on the published sequences. Heavy chain fragments were flanked with HindIII and Esp3I restriction sites. Light chain fragments were flanked with HindIII and BsiWI restriction sites. The mentioned restriction sites were then used to clone the variable domains into the full-length heavy or light chains. For each human monoclonal antibody a plasmid containing the heavy chain and a plasmid containing the light chain was constructed. These plasmids were then co- transfected in a 1:1 ratio in the Expi293 expression system. Supernatants were collected 5 days after transfection by centrifugation at 4000g for 30 minutes, supplemented with 10 mM benzamidine and stored at -80°C until use. Antibody concentrations were determined with a commercially available IgG ELISA (E80- 104, Bethyl). Concentrations ranged from 30.1-137.4 µg / mL. Table 6: Antigen levels of produced monoclonal iTTP patient derived antibodies Antibody Antigen level (µg / mL) 1-403 33.2 1-407 66.1 1-410 37.2 1-416 67.7 1-440 81.2 1-441 137.4 Z1-201 30.1 Z1-303 91.9 Once the antibodies were produced, it was confirmed that these antibodies were indeed not targeting the spacer domain using an ELISA. Here, the plate was coated with 1 µg / mL of 3H9 antibody followed by overnight incubation at 4°C. The next day, the plate was blocked using 2% BSA in PBS. Subsequently, 1.05 nmol of ADAMTS13 or MDTCS variant (truncated ADAMTA13 variant lacking the C- terminal domain including the CUB1 domain and CUB2 domain) in 1% BSA-PBS in a final volume of 175 µL was added to each well. Afterwards 0.033 nmol of the respective antibody in a final volume of 100 µL was added. Detection was performed using a 1:10000 dilution of an anti-IgG1-HRP antibody. This showed that all produced anti-CUB antibodies were able to bind full-length ADAMTS13, but not the MDTCS variants (Figure 7A). This indicates that they are indeed targeting the C-terminal domains of ADAMTS13. Once the binding of the monoclonal antibodies to the C-terminal domains of ADAMTS13 was confirmed, the inhibitory potential of these antibodies was also tested using the aforementioned FRETS-VWF73 activity assay. Here, the assay was performed identically as described above, but now each antibody was added to a final concentration of 9 nM. As a control, an anti-spacer antibody (1-416) was also taken along to confirm that the employed concentration of 9 nM would be sufficient to inhibit ADAMTS13 activity. Indeed, the anti-spacer antibody 1-416 completely inhibited ADAMTS13 activity, while none of the anti-CUB antibodies was able to significantly reduce ADAMTS13 activity (Figure 7B). Moreover, the 1-440 antibody significantly increased activity, and other antibodies showed a non-significant increase in ADAMTS13 activity upon addition of the relative antibody. The increased activity observed for antibody 1-440 is in line with current literature on anti-CUB antibodies, which have been shown to promote conversion from a closed to an open conformation of ADAMTS13 (Deforche et al., 2015; Joshua et al., 2014; Schelpe et al., 2020). This in turn can lead to increased activity for the FRETS- VWF73 substrate as well as the exposure of the normally hidden cryptic spacer epitope for binding of anti-spacer antibodies. Example 6: CUB-NGLY variants reduce binding of monoclonal patient derived antibodies Once the characteristics of the anti-CUB antibodies were tested and confirmed to be in agreement with patient anti-CUB antibodies, the CUB-NGLY variants were screened for the binding of the generated panel of human anti-CUB domain antibodies. This was done using the same ELISA as used in example 5. Here, the 7 anti-CUB antibodies (1-403, 1-407, 1-410, 1-440, 1-441, z1-201, z1-303) and 1 anti- spacer antibody (1-416) were used. Wild-type ADAMTS13 was used as a 100% binding control and MDTCS variant (truncated ADAMTA13 variant lacking the C- terminal domain including the CUB1 domain and CUB2 domain) was included as a negative control for the anti-CUB antibodies and a positive control for the anti- spacer antibody. Additionally, the 1-416 antibody was used to check for equal loading of ADAMTS13 protein variants in this ELISA based set-up. The reactivity is expressed as a heatmap with binding to wild-type ADAMTS13 set as 100% as shown in Figures 8A and 8B. The binding data in Figures 8A and 8B have been calculated with two different calculation methods to cross-check the conclusions drawn from the data. The binding data shown in Figure 8A is expressed as a percentage of binding based on the Optical Density (OD) values. First, background signal (obtained from a well that did not contain any ADAMTS13) was subtracted from the antibody binding OD values. Subsequently, the background subtracted OD value of the antibody binding the CUB-NGLY or MDTCS variants was divided by the background subtracted OD values of the antibody binding to wild-type ADAMTS13. This ratio was then expressed as a percentage of binding. In Figure 8B, an internal standard was used to account for the inherent sigmoidal response curve of an ELISA. Here, a dilution curve of human monoclonal anti-ADAMTS13 antibody II-1 (ranging from 0.11 ng / mL to 250 ng / mL) was included in all binding experiments. Calibration curve was fitted with GraphPad Prism 9.1 using the Sigmoidal, 4PL standard curve, where X is the concentration. All data was interpolated against this binding curve. II-1 binding equivalents of the antibody binding CUB-NGLY or MDTCS variants were then divided by the II-1 binding equivalents of wild-type ADAMTS13 of the same antibody. This ratio was then expressed as a percentage of wild-type ADAMTS13 binding. Data points exceeding the calibration curve were excluded, data points below the standard curve were set to 0% binding. Reactivity was then expressed as a heatmap with binding to wild- type ADAMTS13 set as 100%. Overall, no major differences were observed in Figure 8A and 8B for binding of human monoclonal antibodies to the ADAMTS13 protein variants.1251N and 1255N were able to strongly reduce the binding of 1-407, 1-410 and z1-303. Additionally, they also had a moderate effect on the binding of 1-440 and z1-201. 1251N also had a minor effect on the binding of 1-403.1320N, 1321N, 1322N had no effect on the antibody binding. Lastly, 1295N and 1368N were able to reduce binding of 1-440 and z1-201, where the effect for 1368N was much stronger than for 1295N. Additionally, 1368N was also able to completely reduce binding of the 1- 441 antibody. Combination mutant of 1251N+1368N and 1255N+1368N displayed a strongly reduced binding to antibodies 1-407, 1-410, 1-440, 1-441, z1-201, and z1- 303. Combining 1251N with 1368N also resulted in an additional decrease of the 1- 403 antibody (which is more pronounced when using the second calculation method in Figure 8B), even though 1368N had no effect by itself, suggesting that these two N-glycans act synergistically. Example 7: CUB-NGLY variants of ADAMTS13 reduce auto-antibody binding in iTTP plasma The experiments performed with the human monoclonal antibodies showed that CUB-NGLY variants of ADAMTS13 can reduce binding of anti-CUB antibodies. However, all produced human monoclonal antibodies were derived from a single patient. Therefore, it would be important to also screen the CUB-NGLY variants against a panel of plasma samples of iTTP patients. This would help to establish whether the designed CUB-NGLY variants can potentially be used for the reduction of auto-antibody binding in patients with iTTP. To investigate this, the same ELISA as described in example 5 was used to assess the binding of 9 patient samples to the newly generated CUB-NGLY variants. It has previously been shown that the 9 patient samples selected contained antibodies directed towards the carboxy-terminal TSP2-CUB2 domains (Postmus et al., 2023). This time, instead of adding monoclonal antibodies, patient samples were diluted and added to the ELISA plate. Optimal dilutions had previously been established and were set as the dilution where the patient sample yields an optical density of 1.7 at 450nm when bound to wild-type ADAMTS13. Dilutions ranged from 25x to 200x (Postmus et al., 2023). Detection was performed using a mix of anti-IgG1-HRP, anti-IgG2- HRP, anti-IgG3-HRP, and anti-IgG4-HRP antibodies. To correct for the inherent sigmoidal response curve of an ELISA, a dilution curve of a human monoclonal anti-ADAMTS13 antibody (II-1) was included in all binding experiments. Calibration curve was fitted with GraphPad Prism 9.1 using the Sigmoidal, 4PL standard curve, where X is the log (concentration). All data was extrapolated against this binding curve and then expressed as a percentage of wild-type ADAMTS13 binding. Reactivity was then expressed as a heatmap with binding to wild-type ADAMTS13 set as 100% (Figure 9A). In addition, an alternative calculation method was used, wherein the raw OD values were interpolated against a II-1 calibration curve (ranging from 0.11 ng / mL to 250 ng / mL) which was fitted with GraphPad Prism 9.1 using the Sigmoidal, 4PL standard curve, where X is the concentration (Figure 9D). Compared to wild-type ADAMTS13, all patients still display average binding levels of 83% and 64% of to NGLY3 and FL-5ALA (5ALA) respectively (Figure 9A / B). Similarly, the alternative calculation shows average binding levels of 81% and 60% to NGLY3 and 5ALA (Figure 9D / E). These two ADAMTS13 protein variants prevent the binding of anti-spacer targeting antibodies as previously shown. This indicates that these patients still have a population of antibodies which target other domains of ADAMTS13. When CUB- NGLY combinations, like 1251N+1368N or 1255N+1368N are introduced to either NGLY3 or FL-5ALA (5ALA), a further decrease in antibody binding for 8 / 9 patients can be observed, with an average decrease in binding from 83% to 51% for NGLY3+CUB-NGLY and 64% to 31% for FL-5ALA+CUB-NGLY (Figure 9A). The alternative calculation method revealed reduced average binding of 81% to 47% and 60% to 28% for NGLY3+CUB-NGLY and 5ALA+CUB-NGLY respectively (Figure 9D). Only patient LRB-18 did not show a decrease in binding upon addition of the CUB-NGLY combinations to either NGLY3 or FL-5ALA. The difference in binding of auto-antibodies after the addition of the CUB-NGLY is significant and independent from the two calculation methods described in this example (Figure 9B and Figure 9E); and remarkably similar for both NGLY3 and FL-5ALA (ALA), with the difference being 32% and 33% respectively (Figure 9C). The alternative calculation method yielded differences of 34% and 32% respectively (Figure 9F). Therefore, the results obtained employing two different alternative calculation methods outlined in this example indicate that the results obtained for the CUB- NGLY are highly similar. This indicates that the effect of the CUB-NGLY is independent of any modifications in the spacer domain, and a separate antibody epitope is being targeted. This epitope is also being recognized by pathogenic antibodies present in the majority of patient samples with C-terminal antibodies that were analyzed. Example 8: Generation of additional exemplary CUB N-glycan variants Currently, the CUB-NGLY combination mutants, 1251N+1368N and 1255N+1368N, are able to reduce antibody binding of both monoclonal antibodies as well as of antibodies present in patient samples. To explore whether a single CUB-NGLY variant would also be able to prevent binding of pathogenic CUB domain antibodies that develop in patients with iTTP, an additional panel of CUB- NGLY variants (Table 7) was designed. The selection criteria for the amino acids to mutate were identical to the criteria mentioned in example 1, but now also residues within the spacer-CUB interface have been selected. The novel panel of single CUB-NGLY variants can potentially be used to prevent binding of autoantibodies directed against the CUB domains that develop in patients with iTTP. Synthetic gene fragments flanked by MreI and XhoI were ordered at Azenta and construction of the plasmids was performed as described in example 2, similar to the other CUB-NGLY. Table 7. List of further exemplary CUB-NGLY variants. Mutant Original Sequence Mutated Sequence 1248N RLTWR RNTTR 1249N LTWRK LNWTR 1250N TWRKM TNRTM 1274N QRCGR QNCTR 1326N CRLFI CNLTI 1364N THSLR TNSTR 1365N HSLRT HNLTT 1366N SLRTT SNRTT 1392N SEGFL SNGTL Example 9: Conformation of CUB-NGLY variants In order to assess the conformation of the CUB-NGLY variants, their activity towards the VWF-73 substrate was assessed at both pH 6.0 as well as at pH 7.5. Before the FRETS-VWF73 activity assay, TwinStrep-tagged ADAMTS13 was purified from expression medium using MagStrepXT Beads (2-5090-010, IBA Lifesciences) according to manufacturer protocol. In total 600 µL of expression medium containing ADAMTS13 or CUB-NGLY variants was diluted in 600 µL of binding buffer (100 mM Tris, 150 mM NaCl, pH 8.0) and added to 7.5 µL of MagStrepXT beads. ADAMTS13 protein variants and beads were incubated at 37°C at 1200 rpm for 30 minutes in a tabletop shaker (Thermomixer comfort). Afterwards, beads were washed using binding buffer and ADAMTS13 was eluted with elution buffer (100 mM Tris, 150 mM NaCl, 50 mM biotin, pH 8.0). After purification, ADAMTS13 concentration was determined by ELISA as previously described (Postmus et al., 2023). For the FRETS-VWF73 activity assay, purified ADAMTS13 protein variants were diluted to 0.5 nM in 100 µL FRETS activity buffer (20 mM HEPES, 20 mM Tris- HCl, 20 mM Bis-Tris, 25 mM CaCl2, 0.005% Tween20, pH 6.0 or pH 7.5) and were incubated at room temperature for 10 minutes. Afterwards, 100 µL of 2 µM FRETS-VWF in FRETS activity buffer (pH 6.0 or pH 7.5), was added to ADAMTS13. The reaction was followed at 350 nm excitation and 460 nm emission wavelengths at 30 second intervals for 15 minutes using a TECAN Infinite 200. Initial velocity was determined using linear regression with GraphPad Prism 9.1. The pH dependence of the activity of wild-type ADAMTS13 activity was in line with previous findings, where activity at pH 7.5 was decreased compared to activity at pH 6.0 (Figure 10). Similar findings were observed for 1251N, 1255N, 1320N 1321N, and 1322N (Figure 10). In contrast, 1295N, 1368N, 1251N+1368N, and 1255N+1368N showed identical activity at both pH values, suggesting that these CUB-NGLY variants are present in an open, more active conformation at pH 7.5 when compared to wild-type ADAMTS13. Example 10: Activity of CUB-NGLY variants under flow The activity of the CUB-NGLY variants under flow was also assessed. The following experimental system was being used: highly confluent primary human umbilical vein endothelial cells (HUVECs) were stimulated with histamine under flow to release so-called VWF strings which efficiently recruit platelets thereby forming “beads-on-string” like structures that have been shown to also results from vascular perturbation. ADAMTS13 has been shown to efficiently process these so- called VWF strings (DONG, 2005; Ercig et al., 2021). In this experimental system it was assessed whether the CUB-NGLY variants were capable of processing VWF variants under flow. In order to investigate this, 100.000 HUVEC cells were seeded per channel on collagen coated (50 µg / mL) Ibidi µ-slides. After seeding, medium was refreshed daily. After four days of confluency, flow experiments were conducted. Flow speed was set to 2 mL / min, inducing a shear stress of 2.5 Dynes / cm2. Cells were washed for 5 minutes with M199+0.2%BSA, after which HUVEC were stimulated with 100 µM of histamine for 10 minutes. After histamine stimulation, freshly isolated platelets were added (160x10^9 / L) for 5 minutes. Platelet bound VWF strings were placed in focus, after which 0.1 µg / mL of ADAMTS13 or CUB-NGLY variants were flowed across the newly formed VWF strings for 9 minutes. Every 10 seconds, images were taken with a Zeiss Axio Observer Z1 microscope. All experiments containing ADAMTS13 or variants were performed in duplicate. Platelets were counted on each frame using FIJI, and platelet numbers were expressed as a percentage of the amount of platelets present in the first frame. All tested ADAMTS13 protein variants were able to effectively cleave VWF-multimers under flow when compared to a negative control. Moreover, 1251N+1368N and 1255N+1368N displayed similar activity to wild-type ADAMTS13, showing that CUB-NGLY variants do not impair the ability of ADAMTS13 to cleave VWF multimers under flow (Figure 11A). Representative images of negative control (no ADAMTS13 added) and wild-type ADAMTS13 as well as 1251N+1368N and 1255N+1368N variants at timepoint zero, two, and nine minutes can be found in Figure 11B. References Austin SK, Starke RD, Lawrie AS, Cohen H, Machin SJ, Mackie IJ. The VWF / ADAMTS13 axis in the antiphospholipid syndrome: ADAMTS13 antibodies and ADAMTS13 dysfunction. Br J Haematol. 2008 May;141(4):536- 44. doi: 10.1111 / j.1365-2141.2008.07074.x Bitsadze V, Bouvier S, Khizroeva J, Cochery-Nouvellon É, Mercier É, Perez-Martin A, Makatsariya A, Gris JC. Early ADAMTS13 testing associates with pre- eclampsia occurrence in antiphospholipid syndrome. Thromb Res.2021 Apr 27;203:101-109. doi: 10.1016 / j.thromres.2021.04.021 Burbelo PD1, O'Hanlon TP. New autoantibody detection technologies yield novel insights into autoimmune disease. Curr Opin Rheumatol.2014 Nov;26(6):717- 23 Cabin, D. E., Shimazu, K., Murphy, D., Cole, N. B., Gottschalk, W., McIlwain, K. L., Orrison, B., Chen, A., Ellis, C. E., Paylor, R., Lu, B., & Nussbaum, R. L. (2002). Synaptic vesicle depletion correlates with attenuated synaptic responses to prolonged repetitive stimulation in mice lacking alpha-synuclein. The Journal of Neuroscience : The Official Journal of the Society for Neuroscience, 22(20), 8797–8807. https: / / doi.org / 22 / 20 / 8797 [pii] Deforche, L., Roose, E., Vandenbulcke, A., Vandeputte, N., Feys, H. B., Springer, T. A., Mi, L. Z., Muia, J., Sadler, J. E., Soejima, K., Rottensteiner, H., Deckmyn, H., De Meyer, S. F., & Vanhoorelbeke, K. (2015). Linker regions and flexibility around the metalloprotease domain account for conformational activation of ADAMTS-13. Journal of Thrombosis and Haemostasis, 13(11), 2063–2075. https: / / doi.org / 10.1111 / jth.13149 Dong, J. F. (2005). Cleavage of ultra‐large von Willebrand factor by ADAMTS‐13 under flow conditions. Journal of Thrombosis and Haemostasis, 3(8), 1710– 1716. https: / / doi.org / https: / / doi.org / 10.1111 / j.1538-7836.2005.01360.xDutt et al, Real-world experience with caplacizumab in the management of acute TTP. Blood 2021;137(13):1731-1740 Ercig, B., Graça, N. A. G., Kangro, K., Arfman, T., Wichapong, K., Hrdinová, J., Kaijen, P., van Alphen, F. P. J., van den Biggelaar, M., Vanhoorelbeke, K., Veyradier, A., Coppo, P., Reutelingsperger, C., Nicolaes, G. A. F., Männik, A., Voorberg, J., & Consortium, on behalf of the P. (2021). N-glycan–mediated shielding of ADAMTS13 prevents binding of pathogenic autoantibodies in immune-mediated TTP. Blood, 137(19), 2694–2698. https: / / doi.org / 10.1182 / blood.2020007972 Ercig, B., Wichapong, K., Reutelingsperger, C. P. M., Vanhoorelbeke, K., Voorberg, J., & Nicolaes, G. A. F. (2018). Insights into 3D Structure of ADAMTS13: A Stepping Stone towards Novel Therapeutic Treatment of Thrombotic Thrombocytopenic Purpura. Thromb Haemost, 118(01), 28–41. Graça AG N, Ercig B, Velasquez Pereira LC, et al. Modifying ADAMTS13 to modulate binding of pathogenic autoantibodies of patients with acquired thrombotic thrombocytopenic purpura.2019; Haematologica. 2019 Nov 21. pii: haematol.2019.226068. doi: 10.3324 / haematol.2019.226068 Jian, C., Xiao, J., Gong, L., Skipwith, C. G., Jin, S. Y., Kwaan, H. C., & Zheng, X. L. (2012). Gain-of-function ADAMTS13 variants that are resistant to autoantibodies against ADAMTS13 in patients with acquired thrombotic thrombocytopenic purpura. Blood, 119(16), 3836–3843. https: / / doi.org / 10.1182 / blood-2011-12-399501 Joshua, M., Jian, Z., Garima, G., L., H. S., D., F. K., B., F. H., Louis, D., Karen, V., A., W. L., Robyn, R., Harish, T. N., E., H. J., & Evan, S. J. (2014). Allosteric activation of ADAMTS13 by von Willebrand factor. Proceedings of the National Academy of Sciences, 111(52), 18584–18589. https: / / doi.org / 10.1073 / pnas.1413282112 Kangro, K., Roose, E., Joly, B. S., Sinkovits, G., Falter, T., von Auer, C., Rossmann, H., Reti, M., Voorberg, J., Prohászka, Z., Lämmle, B., Coppo, P., Veyradier, A., De Meyer, S. F., Männik, A., & Vanhoorelbeke, K. (2021). Anti-ADAMTS13 autoantibody profiling in patients with immune-mediated thrombotic thrombocytopenic purpura. Blood Advances, 5(17), 3427–3435. https: / / doi.org / 10.1182 / bloodadvances.2020004172 Kelwick R, Desanlis I, Wheeler GN, Edwards DR. The ADAMTS (A Disintegrin and Metalloproteinase with Thrombospondin motifs) family. Genome Biol. 2015 May 30;16:113 Kokame K, Nobe Y, Kokubo Y, Okayama A, Miyata T. FRETS-VWF73, a first fluorogenic substrate for ADAMTS13 assay. Br J Haematol. 2005 Apr;129(1):93-100 Kim, H. J., Xu, Y., Petri, A., Vanhoorelbeke, K., Crawley, J. T. B., & Emsley, J. (2021). Crystal structure of ADAMTS13 CUB domains reveals their role in global latency. Science Advances, 7(16), 1–12. https: / / doi.org / 10.1126 / sciadv.abg4403 Klaus, C., Plaimauer, B., Studt, J.-D., Dorner, F., Lämmle, B., Mannucci, P. M., & Scheiflinger, F. (2004). Epitope mapping of ADAMTS13 autoantibodies in acquired thrombotic thrombocytopenic purpura. Blood, 103(12), 4514–4519. https: / / doi.org / 10.1182 / blood-2003-12-4165 Long Zheng, X., Wu, H. M., Shang, D., Falls, E., Skipwith, C. G., Cataland, S. R., Bennett, C. L., & Kwaan, H. C. (2010). Multiple domains of ADAMTS13 are targeted by autoantibodies against ADAMTS13 in patients with acquired idiopathic thrombotic thrombocytopenic purpura. Haematologica, 95(9), 1555– 1562. https: / / doi.org / 10.3324 / haematol.2009.019299 De Maeyer B, De Meyer SF, Feys HB, Pareyn I, Vandeputte N, Deckmyn H, Vanhoorelbeke K. The distal carboxyterminal domains of murine ADAMTS13 influence proteolysis of platelet-decorated VWF strings in vivo. J Thromb Haemost.2010 Oct;8(10):2305-12 Mazepa MA, Masias C, Chaturvedi S. How targeted therapy disrupts the treatment paradigm for acquired TTP: the risks, benefits, and unknowns. Blood. 2019 Aug 1;134(5):415-420 Muia, J., Gao, W., Haberichter, S. L., Dolatshahi, L., Zhu, J., Westfield, L. A., Covill, S. C., Friedman, K. D., & Sadler, J. E. (2013). An optimized fluorogenic ADAMTS13 assay with increased sensitivity for the investigation of patients with thrombotic thrombocytopenic purpura. Journal of Thrombosis and Haemostasis, 11(8), 1511–1518. https: / / doi.org / https: / / doi.org / 10.1111 / jth.12319Ostertag, E. M., Kacir, S., Thiboutot, M., Gulendran, G., Zheng, X. L., Cines, D. B., & Siegel, D. L. (2016). ADAMTS13 autoantibodies cloned from patients with acquired thrombotic thrombocytopenic purpura: 1. Structural and functional characterization in vitro. Transfusion, 56(7), 1763–1774. https: / / doi.org / https: / / doi.org / 10.1111 / trf.13584 Pos, W., Crawley, J. T. B., Fijnheer, R., Voorberg, J., Lane, D. A., & Luken, B. M. (2010). An autoantibody epitope comprising residues R660, Y661, and Y665 in the ADAMTS13 spacer domain identifies a binding site for the A2 domain of VWF. Blood, 115(8), 1640–1649. https: / / doi.org / 10.1182 / blood-2009-06-229203 Pos W, Crawley JTB, Fijnheer R, et al. An autoantibody epitope comprising residues R660, Y661, and Y665 in the ADAMTS13 spacer domain identifies a binding site for the A2 domain of VWF. Blood.2010;115(8):1640–1649 Pos W, Sorvillo N, Fijnheer R, et al. Residues Arg568 and Phe592 contribute to an antigenic surface for anti-Adamts13 antibodies in the spacer domain. Haematologica. 2011;96(11):1670–1677 Postmus, T., Graça, N. A. G., Ferreira de Santana, J., Ercig, B., Langerhorst, P., Luken, B., Joly, B. S., Vanhoorelbeke, K., Veyradier, A., Coppo, P., & Voorberg, J. (2023). Impact of N-glycan mediated shielding of ADAMTS-13 on the binding of pathogenic antibodies in immune thrombotic thrombocytopenic purpura. Journal of Thrombosis and Haemostasis. https: / / doi.org / https: / / doi.org / 10.1016 / j.jtha.2023.08.017 Roose et al. Open ADAMTS13, induced by antibodies, is a biomarker for subclinical immune-mediated thrombotic thrombocytopenic purpura Blood (2020) 16;136(3):353-361 Ramsi M, Al Ali AS. Thrombocytopenia-associated multiple-organ failure (TAMOF): recognition and management. BMJ Case Rep.2018 Aug 27;2018:bcr2018225594. doi: 10.1136 / bcr-2018-225594 Schelpe, A. S., Petri, A., Roose, E., Pareyn, I., Deckmyn, H., De Meyer, S. F., Crawley, J. T. B., & Vanhoorelbeke, K. (2020). Antibodies that conformationally activate ADAMTS13 allosterically enhance metalloprotease domain function. Blood Advances, 4(6), 1072–1080. https: / / doi.org / 10.1182 / bloodadvances.2019001375 Scully M, Cataland SR, Peyvandi F, Coppo P, Knöbl P, Kremer Hovinga JA, Metjian A, de la Rubia J, Pavenski K, Callewaert F, Biswas D, De Winter H, Zeldin RK; HERCULES Investigators. Caplacizumab Treatment for Acquired Thrombotic Thrombocytopenic Purpura. N Engl J Med.2019 Jan 24;380(4):335-346Thomas, M. R., de Groot, R., Scully, M. A., & Crawley, J. T. B. (2015). Pathogenicity of Anti-ADAMTS13 Autoantibodies in Acquired Thrombotic Thrombocytopenic Purpura. EBioMedicine, 2(8), 942–952. https: / / doi.org / 10.1016 / j.ebiom.2015.06.007 Sins JWR, Schimmel M, Luken BM, Nur E, Zeerleder SS, van Tuijn CFJ, Brandjes DPM, Kopatz WF, Urbanus RT, Meijers JCM, Biemond BJ, Fijnvandraat K. Dynamics of von Willebrand factor reactivity in sickle cell disease during vaso- occlusive crisis and steady state. J Thromb Haemost.2017 Jul;15(7):1392- 1402. doi: 10.1111 / jth.13728. South, K., Luken, B. M., Crawley, J. T. B., Phillips, R., Thomas, M., Collins, R. F., Deforche, L., Vanhoorelbeke, K., & Lane, D. A. (2014). Conformational activation of ADAMTS13. Proceedings of the National Academy of Sciences of the United States of America, 111(52), 18578–18583. https: / / doi.org / 10.1073 / pnas.1411979112 Turecek PL, Peck RC, Rangarajan S, Reilly-Stitt C, Laffan MA, Kazmi R, James I, Dushianthan A, Schrenk G, Gritsch H, Ewenstein BM, Mellgard B, Erdlenbruch W, Jain N, Binder NB, Mumford AD. Recombinant ADAMTS13 reduces abnormally up-regulated von Willebrand factor in plasma from patients with severe COVID-19. Thromb Res.2021 May;201:100-112. doi: 10.1016 / j.thromres.2021.02.012 Verbij et al. Identification of glycans on plasma-derived ADAMTS13 Blood. 2016 Nov 24;128(21):e51-e58. doi: 10.1182 / blood-2016-06-720912. Xiao J, Jin SY, Xue J, Sorvillo N, Voorberg J, Zheng XL. Essential domains of a disintegrin and metalloprotease with thrombospondin type 1 repeats-13 metalloprotease required for modulation of arterial thrombosis. Arterioscler Thromb Vasc Biol. 2011 Oct;31(10):2261-9

Claims

Claims 1. An ADAMTS13 protein variant comprising one or more N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as defined by SEQ ID NO:

43.

2. The ADAMTS13 protein variant according to claim 1 comprising one or more N-linked glycosylation sites at amino acid residue 1251, 1255, 1295 and / or 1368 of the ADAMTS13 sequence as defined by SEQ ID NO:

43.

3. The ADAMTS13 protein variant according to any one of the preceding claims comprising: (i) one or more N-linked glycosylation site in part of the CUB1 domain comprising amino acid residues 1246-1258, 1272-1276, and / or 1295-1297 of ADAMTS13 as defined by SEQ ID NO: 43; and / or (ii) one or more N-linked glycosylation site in part of the CUB2 domain comprising amino acid residues 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as defined by SEQ ID NO:

43.

4. The ADAMTS13 protein variant according to any one of the preceding claims comprising: (i) an N-linked glycosylation site at amino acid residue 1251 and at amino acid residue 1368 of the ADAMTS13 sequence as defined by SEQ ID NO: 43; or (ii) an N-linked glycosylation site at amino acid residue 1255 and at amino acid residue 1368 of the ADAMTS13 sequence as defined by SEQ ID NO:

43.

5. The ADAMTS13 protein variant according to any one of the preceding claims further comprising a further mutation at one or more amino acid residues, preferably wherein said mutation at one or more amino acid residues is in a spacer domain comprising residues 556 to 685 of wild-type ADAMTS13 as defined by SEQ ID NO:

43.

6. The ADAMTS13 protein variant according to claim 5, further comprising one or more further mutations that reduce binding by autoantibodies directed to the spacer domain, preferably wherein further one or more N-linked glycosylation sites are added as compared to wild-type ADAMTS13 and / or one or more existingN-linked glycosylation sites are shifted as compared to wild-type ADAMTS13 in the spacer domain.

7. The ADAMTS13 protein variant according to claim 6, wherein the one or more N-linked glycosylation sites are added and / or shifted at amino acid residue 568, 591, 608, 609, 636, 637, 665 and / or 668 of wild-type ADAMTS13 as defined by SEQ ID NO: 43, preferably at amino acid residue 608, 609 and / or 665 of wild-type ADAMTS13 as defined by SEQ ID NO: 43, preferably comprising an N-linked glycosylation site at amino acid residue 608 of ADAMTS13 as defined by SEQ ID NO:

43.

8. The ADAMTS13 protein variant according to any one of the preceding claims further comprising one or more mutations at one or more amino acid residues selected from the group consisting of R568, L591, F592, K608, R636, L637, L668, L591, F592, R636, L637, R660, Y661, Y665, and L668, , preferably comprising one or more mutation selected from the group consisting of R568K, R568A, R568N, L591A, F592Y, F592A, F592N, K608N, R636A, L637A, R660K, R660A, R660N, Y661F, Y661A, Y661N, Y665F, Y665A, Y665N, and L668A, more preferably comprising mutations R568A and Y665A or mutations L591A, R636A, L637A, and L668A.

9. The ADAMTS13 protein variant according to any one of the preceding claims comprising an N-glycan at said one or more N- linked glycosylation sites.

10. A nucleic acid construct comprising a nucleic acid sequence encoding an ADAMTS13 protein variant according to any one of claims 1-9.

11. A method for reducing plasma clearance of an ADAMTS13 protein variant, such as an ADAMTS13 protein variant with reduced binding to auto- antibodies specific for the spacer domain as compared to wild-type ADAMTS13 protein, said method comprising introducing into the ADAMTS13 protein variant one or more N-linked glycosylation sites in part of the CUB domain comprising amino acid residues 1246-1258, 1272-1276, 1295-1297, 1326-1328, 1361-1370 and / or 1392-1394 of the ADAMTS13 sequence as defined by SEQ ID NO: 43, thereby reducing plasma clearance of the ADAMTS13 variant.

12. An ADAMTS13 protein variant according to any one of claims 1-9 or a nucleic acid construct according to claim 10 for use as a medicament, preferably as an antithrombotic agent.

13. An ADAMTS13 protein variant according to any one of claims 1-9 or a nucleic acid construct according to claim 10 for use in prevention and / or treatment of a disorder characterized by aberrant Von Willebrand Factor (VWF) activity and / or VWF processing.

14. An ADAMTS13 protein variant according to any one of claims 1-9 or a nucleic acid construct according to claim 10 for use in the treatment of a disorder characterized by aberrant Von Willebrand Factor (VWF) activity and / or VWF processing in a patient that inadequately responds to treatment that reduces ADAMTS13 autoantibody binding to the spacer domain, preferably wherein said disorder is a thrombotic disease, preferably a thrombotic microangiopathy, more preferably a disorder selected from the group consisting of thrombotic thrombocytopenic purpura (TTP), including immune-mediated TTP (iTTP), hemolytic–uremic syndrome (HUS), ischemic stroke, systemic thrombosis, COVID19, antiphospholipid syndrome, pre-eclampsia / HELLP syndrome, sepsis and sickle cell disease.

15. The ADAMTS13 protein variant or nucleic acid construct for use according to any one of claims 12-14, wherein the subject that is treated is characterized by having autoantibodies against the ADAMTS13 CUB domain.

Images