Application of MxA quantitative detection agent in acute respiratory infection course monitoring

Abstract

The invention relates to the technical field of immunodiagnosis, in particular to application of a quantitative detection agent of MxA in acute respiratory infection course monitoring. According to the invention, early warning can be provided for disease evolution, the prediction of treatment effect and disease prognosis can be assisted, antiviral and antibiotic medication can be guided, and drug resistance evaluation can be assisted.

Description

Technical Field

[0001] The present invention relates to the field of immuno-diagnostic technologies, and more particularly, to the application of a quantitative detection agent for MxA in the monitoring of the course of acute respiratory infections. Background Art

[0002] Acute respiratory infection (ARI) is the most burdensome infectious disease globally, causing approximately 12.8 billion new cases annually worldwide, of which 70% - 80% are caused by viral infections. Common respiratory viruses include influenza virus, severe acute respiratory syndrome coronavirus 2, adenovirus, respiratory syncytial virus, etc. Respiratory virus infections not only have a high incidence rate, but also pose a continuous pressure on the public health system due to their rapid transmission.

[0003] Although most ARI cases present a self-limiting course, clinical observations show that some patients with viral ARI may develop secondary bacterial infections and even serious complications such as bronchitis and pneumonia, resulting in poor prognosis. Existing clinical practices have shown that traditional symptom monitoring has obvious lag, which may cause viral ARI patients at high risk of complications to miss the optimal intervention window period.

[0004] Currently, there is a lack of effective biomarkers for monitoring the condition of viral ARI in clinical practice. Conventional reliance on vital sign monitoring, biochemical indicators (such as blood routine, CRP) and imaging examinations has obvious limitations: the test results of mild patients often do not change significantly, and organ function damage often occurs when the indicators are significantly abnormal. This monitoring lag leads to delays in clinical intervention timing.

[0005] Although viral nucleic acid testing is the main means of current diagnosis, it has defects in disease monitoring: (1) Except for influenza virus and severe acute respiratory syndrome coronavirus 2, most respiratory viruses lack commercial detection kits; (2) PCR can only detect the presence of viral nucleic acid and cannot distinguish between active virus and residual RNA (such as nucleic acid of recovered patients with novel coronavirus can remain positive for several months); (3) There is no significant correlation between the viral load (CT value) of severe patients and the severity of the disease. In addition, nucleic acid testing requires professional laboratory support and has a low penetration rate in primary hospitals.

[0006] Although the plaque assay based on cell culture can evaluate virus activity, it is time-consuming and costly, and is only applicable to scientific research scenarios. Therefore, there is an urgent clinical need for rapid and simple virus infection markers to assist in monitoring the condition changes of patients, optimizing their treatment courses, and thus improving the prognosis of patients.

[0007] Currently, there is no specific biomarker established in international guidelines that can be used to reflect the evolution of viral ARI in real time, and this gap directly affects the implementation of precision medicine. Summary of the Invention

[0008] The present invention encompasses the following technical solutions: Use of a quantitative detection agent for MxA in preparing a kit for monitoring the course of acute respiratory tract infection.

[0009] An acute respiratory tract infection course monitoring system, the system comprising: A sample information processing module, a diagnosis module, and an information output module; The sample information module is used to receive information of a subject being examined with acute respiratory tract infection, and the information of the subject being examined at least includes the dynamic quantitative detection result of MxA in a sample from the patient; The diagnosis module receives the information input from the sample information processing module, compares the dynamic changes of MxA with standard features to obtain a monitoring result, and outputs it to the information output module; Wherein the standard features are the MxA change features of non-complicated respiratory virus infected patients without complications.

[0010] As an effector molecule of the interferon signaling pathway, MxA has good dynamic characteristics: ① Under the stimulation of type I / III interferon, its transcriptional level can be rapidly up-regulated within 1-2 hours after infection; ② Protein expression reaches a peak at 16 hours; ③ The plasma half-life is stable (2.3 days). These characteristics make it an ideal target for disease monitoring. Based on the above technical status quo, the present invention first proposes to establish a disease assessment system for viral ARI by dynamically monitoring the concentration change of MxA to achieve early warning of viral ARI, efficacy monitoring, and prognosis stratification. The present invention helps to provide early warning for the evolution of the disease, assist in predicting the treatment effect and disease prognosis, guide antiviral and antibiotic medication, and assist in drug resistance assessment. Brief Description of the Drawings

[0011] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0012] Figure 1 It is the MxA time-concentration kinetic change curve provided by an embodiment of the present invention. Detailed Embodiments

[0013] Reference will now be made in detail to embodiments of the present invention, one or more examples of which are described below. Each example is provided by way of explanation and not limitation of the present invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the scope or spirit of the present invention. For example, features illustrated or described as part of one embodiment can be used in another embodiment to yield a still further embodiment.

[0014] Unless otherwise noted, all terms used to disclose the present invention (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. Through further guidance, the following definitions are used to better understand the teachings of the present invention. The terms used in the specification of the present invention herein are for the purpose of describing specific embodiments only and are not intended to limit the present invention.

[0015] In the present invention, unless otherwise noted, scientific and technical terms used herein have the meanings commonly understood by those skilled in the art. Also, the terms and laboratory procedures related to protein and nucleic acid chemistry, molecular biology, cell and tissue culture, microbiology, and immunology used herein are terms and conventional procedures widely used in the respective fields. At the same time, to better understand the present invention, the following definitions and explanations of related terms are provided.

[0016] The term "and / or", "or / and", "and / or" as used herein includes any one of two or more related listed items, and also includes any and all combinations of the related listed items, and the any and all combinations include any two related listed items, any more related listed items, or the combination of all related listed items. It should be noted that when at least two conjunctions selected from "and / or", "or / and", "and / or" are used to connect at least three items, it should be understood that in the present invention, this technical solution undoubtedly includes the technical solution connected by "logical AND", and also undoubtedly includes the technical solution connected by "logical OR". For example, "A and / or B" includes three parallel solutions: A, B, and A + B. Another example, the technical solution of "A, and / or, B, and / or, C, and / or, D" includes any one of A, B, C, D (that is, the technical solution connected by "logical OR"), and also includes any and all combinations of A, B, C, D, that is, includes the combination of any two or any three of A, B, C, D, and also includes the four-item combination of A, B, C, D (that is, the technical solution connected by "logical AND").

[0017] The terms "comprising", "including" and "containing" used in the present invention are synonyms, which are inclusive or open-ended and do not exclude additional, unrecited members, elements or method steps.

[0018] In the present invention, the numerical ranges represented by endpoints include all the numerical values and fractions included within such ranges, as well as the recited endpoints.

[0019] As used herein, the reference to "about" a value or parameter includes (and describes) embodiments directed to the value or parameter itself. For example, the description of "about X" includes the description of "X".

[0020] As used herein, unless otherwise indicated, the singular forms of the articles "a", "an", and "the" include plural referents.

[0021] In the present invention, descriptions such as "a plurality of", "a variety of", etc., unless otherwise specified, refer to a quantity greater than or equal to 2.

[0022] In the present invention, among the technical features described in an open-ended manner, it includes a closed technical solution composed of the recited features, as well as an open technical solution including the recited features.

[0023] In the present invention, "preferred", "better", "more preferred", "preferably" are only used to describe embodiments or examples with better effects, and it should be understood that they do not constitute a limitation to the protection scope of the present invention. In the present invention, "optionally", "optional", "optional" mean that it can be either present or absent, that is, it refers to any one of the two alternative schemes of "present" or "absent". If "optional" appears in a technical solution in multiple places, unless otherwise specified and there is no contradiction or mutual restriction relationship, each "optional" is independent of each other.

[0024] In the present invention, "MxA" refers to "myxovirus resistance protein A". Unless otherwise stated, "MxA" can be understood as "MxAmRNA" and / or "MxA protein" according to the context, and can be replaced by "marker", "biochemical marker", "acute respiratory infection marker". Specifically, it refers to the molecule to be used as the target for analyzing the experimental samples of patients.

[0025] The first aspect of the present invention relates to the use of a quantitative detection agent for MxA in the preparation of a kit for monitoring the course of acute respiratory infection.

[0026] As a cytoplasmic protein with antiviral effects induced by interferon, MxA can cover all common respiratory viruses. In the present invention, we use detection methods including fluorescence immunoassay to measure MxA in blood samples, which have the advantages of accurate, simple, inexpensive, and rapid detection; at the same time, MxA starts to be secreted 1.2 h after virus infection and has a half-life of 2.3 days, which can accurately and timely reflect the virus infection status and virus clearance. The present invention realizes the monitoring of the condition of respiratory virus infection by dynamically measuring the MxA level, can accurately carry out anti-infection treatment, and improve the prognosis of patients.

[0027] In the present invention, MxA is used as a molecular marker for monitoring the course of acute respiratory tract infection and is detected.

[0028] The molecular marker mRNA used as a marker in the present invention is expected to include its full-length ribonucleotide sequence, or a naturally occurring variant, or a fragment of the full-length sequence and the variant, particularly a fragment that can be detected and its specific sequence determined, more preferably a fragment that can be distinguished from other RNA sequences in blood. Preferably, it contains at least 7, 8, 9, 10, 11, 12, 15 or 20 consecutive ribonucleotides of the said full-length ribonucleotide sequence.

[0029] The molecular marker protein used as a marker in the present invention is expected to include a naturally occurring variant of the said protein and a fragment of the said protein or the variant, particularly an immunologically detectable fragment. The immunologically detectable fragment preferably contains at least 5, 6, 7, 8, 9, 10, 11, 12, 15 or 20 consecutive amino acids of the said marker polypeptide. For example, the expression "MxA protein" includes the complete protein sequence of MxA and the said marker polypeptide as defined above.

[0030] Those skilled in the art will recognize that ribonucleotides / proteins / polypeptides released by cells or ribonucleotides present in the extracellular matrix may be damaged (e.g., during an inflammatory process) and may be degraded or cleaved into such fragments. As will be understood by those skilled in the art, mRNA, protein or a fragment thereof may also exist as part of a complex. Such a complex may also be used as a marker in the sense of the present invention. Additionally, in an alternative, the marker polypeptide or its variant may carry post-translational modifications. Non-limiting examples of post-translational modifications are glycosylation, acylation and / or phosphorylation. "Naturally occurring variant" should be understood that genes in higher animals are usually accompanied by a high frequency of polymorphisms. There are also many molecules that generate isoforms with mutually different amino acid sequences during the splicing process.

[0031] In some embodiments, the quantitative detection agent includes a reagent for detecting changes in MxA mRNA, which is applicable to at least one of the following methods: Sequencing, polymerase chain reaction (PCR), isothermal amplification reaction, resonance light scattering method, bio-mass spectrometry, electrochemical analysis, gel electrophoresis, capillary electrophoresis, microarray, CRISPR-Cas detection system.

[0032] Among them, nucleic acid sequencing can be Maxam-Gilbert sequencing, chain termination method, shotgun sequencing, bridge PCR, single molecule real-time sequencing, ion semiconductor (ion torrent sequencing), synthesis sequencing, ligation sequencing (SOLiD sequencing), chain termination (Sanger sequencing), massively parallel signature sequencing (MPSS), polymerase cloning sequencing, 454 pyrosequencing, Illumina (Solexa) sequencing, DNA nanoball sequencing, Heliscope single molecule sequencing, single molecule real-time (SMRT) sequencing, nanopore DNA sequencing, tunneling current DNA sequencing, hybridization sequencing, mass spectrometry sequencing, microfluidic Sanger sequencing, microscopy-based techniques, RNAP sequencing, and in vitro viral high-throughput sequencing.

[0033] Among them, PCR is preferably qRT-PCR and digital PCR.

[0034] Among them, broad sense isothermal techniques can be further divided into the following methods: methods that rely on primer displacement to initiate repeated template copying (illustrated below, HDA (helicase-dependent amplification), exonuclease-dependent amplification (EP1866434), recombinase polymerase amplification (RPA), recombinase-mediated amplification method (RAA), loop-mediated amplification (LAMP), rolling circle amplification technique (RCA), multiple displacement amplification (MDA), cross-priming amplification technique (CPA)) and methods that rely on the continuous reuse or de novo synthesis of a single primer molecule, SDA (strand displacement amplification and nucleic acid-based amplification (NASBA and TMA)).

[0035] Among them, according to the type of nucleic acid molecule detected, CRISPR / Cas technology nucleic acid detection can be divided into DNA (CRISPR / Cas9, CRISPR / Cas12, and CRISPR / Cas12 recognize DNA sequences) and RNA (CRISPR / Cas13 recognizes RNA sequences) detection.

[0036] In some embodiments, the quantitative detection agent includes a probe and / or primer that can specifically bind to MxA mRNA or cDNA. In some embodiments, the probe and / or the primer is labeled with a detectable label.

[0037] In some embodiments, the quantitative detection agent includes a reagent for detecting changes in MxA protein, which is applicable to at least one of the following detection methods: immunoassay, bio-mass spectrometry, lectin-based detection method, and aptamer-based detection method.

[0038] As a method for measuring the molecular marker of the present invention, for example, as long as it is a method for specifically measuring the molecular marker protein, any known method such as immunoassay and mass spectrometry can be used. Among the reagents used in measuring the marker protein of the present invention, antibodies, lectins, aptamers, etc. can be used as detection agents.

[0039] As for the immunoassay method, there is no particular limitation, and various enzyme immunoassay methods, radioimmunoassay (RIA), enzyme-linked immunosorbent assay (ELISA), double monoclonal antibody sandwich immunoassay, monoclonal polyclonal antibody sandwich immunoassay, immunostaining method, immunofluorescence method, Western blotting method, biotin-avidin method, immunoprecipitation method, colloidal gold agglutination method, immunochromatography method, latex agglutination method (LA), and immunoturbidimetry method (TIA), etc. can be cited.

[0040] As the reagent used in the immunoassay method, commercially available anti-MxA antibodies can be used, or antibodies can be prepared by conventional methods based on the known amino acid sequence of MxA.

[0041] As long as it is an antibody that can detect MxA protein, the animal species and clone from which it is derived are not particularly limited. Antibodies derived from rabbits, goats, mice, rats, guinea pigs, horses, sheep, camels, chickens, etc. can be cited, and both monoclonal antibodies and polyclonal antibodies are acceptable. In addition, antibodies suitable for specifically binding to all subtypes of MxA protein can be used. Of course, recombinant antibodies, Fab, Fab', or F(ab')2 fragments and other such fragments can also be used.

[0042] As for the mass spectrometry method, there is no particular limitation, and a mass spectrometer that combines an ion source using electrospray ionization (ESI), matrix-assisted laser desorption ionization (MALDI), surface-enhanced laser desorption ionization (SELDI), etc. with a time-of-flight analyzer (TOF), ion trap analyzer (IT), Fourier transform analyzer (FT), etc. can be used. LC-MS, CE-MS, etc. formed by connecting a mass spectrometer with a separation device such as high-performance liquid chromatography (HPLC) or capillary electrophoresis (CE) can be used. In addition, as methods for obtaining mass spectrometry data, data-independent analysis (DIA), data-dependent analysis (DDA), multiple reaction monitoring method (MRM), etc. can be cited. Mass spectrometry also includes cases where the sample is subjected to stable isotope labeling with iTRAQ reagents (SCIEX Corporation), etc.

[0043] In some embodiments, the quantitative detection agent includes an antibody.

[0044] In some embodiments, the antibody is a monoclonal antibody or a polyclonal antibody.

[0045] In some embodiments, the quantitative detection agent is selected from: ELISA reagents, Western Blot reagents, immunofluorescence reagents or immunohistochemical reagents.

[0046] In some embodiments, the acute respiratory infection is a viral infection.

[0047] In some embodiments, the pathogens of the viral infection include: influenza virus (preferably including influenza A virus and / or influenza B virus), coronavirus (preferably including human coronavirus, more preferably including severe acute respiratory syndrome coronavirus 2), rhinovirus, respiratory syncytial virus, metapneumovirus, adenovirus, and parainfluenza virus.

[0048] In the present invention, terms such as "biological sample", "sample" etc. refer to animal samples; tissues or organs, tissue lysates that can be from animals (preferably including at least mammals, such as primates, including humans); cells (cells in a subject, directly taken from a subject, or maintained in culture or from a cultured cell line), cell lysates (or lysate fractions) or cell extracts; solutions containing one or more molecules derived from cells, cell materials; or solutions containing nucleic acids that are naturally or non-naturally occurring and can be assayed as described in the present invention. In some embodiments, the test samples of the kit are selected from: blood (including whole blood, serum or plasma), sputum, oropharyngeal swab (OPS), nasopharyngeal swab (NPS), tracheal aspirate (TA), bronchoalveolar lavage (BAL), nasopharyngeal aspirate (NPA), nasopharyngeal wash (NPW), nasal swab (NS), nasal aspirate (NA), nasal wash (NW), and combined nasal and oropharyngeal swabs (NS+OPS). In preferred embodiments, the test samples of the kit are selected from: whole blood, serum or plasma.

[0049] In some embodiments, the subject of the kit is a mammal.

[0050] In some embodiments, the subject of the kit is a primate.

[0051] In some embodiments, the subject of the kit is a human.

[0052] As is well known to those skilled in the art, the ideal scenario for diagnosis is a situation where a single event or process causes various diseases, for example, in infectious diseases. In all other cases, correct diagnosis can be very difficult, especially when the etiology of the disease is not fully understood. As will be appreciated by a skilled person, for a given multifactorial disease, a diagnosis without a biochemical marker is 100% specific and 100% sensitive. Determining the course of change of acute respiratory infection in a subject's sample compared to a control sample can be carried out using statistical methods well known in the art and confirmed using confidence intervals and / or p values. In some embodiments, the confidence interval is 90%, 95%, 97.5%, 98%, 99%, 99.5%, 99.9% or 99.99% and the p value is 0.1, 0.05, 0.025, 0.02, 0.01, 0.005, 0.001 or 0.0001. In addition, additional biochemical markers / diagnostic methods can be used to participate in the assessment of the presence or severity of the disease to improve the accuracy of the assessment; indeed, in routine clinical diagnosis, various clinical symptoms and biological markers are usually considered comprehensively for the diagnosis, treatment and control of potential diseases.

[0053] In some embodiments, the kit can also be used for at least one of predicting the efficacy of acute respiratory infection, predicting the prognosis, guiding antiviral and antibiotic medication, and predicting drug resistance.

[0054] According to another aspect of the present invention, there is also provided a system for monitoring the course of acute respiratory infection, the system comprising: a sample information processing module, a diagnosis module and an information output module; The sample information module is used to receive information of a subject being examined for acute respiratory infection, and the information of the subject being examined at least includes the dynamic quantitative detection results of MxA in the sample from the patient; The diagnosis module receives the information input from the sample information processing module, compares the dynamic changes of MxA with the standard features to obtain a monitoring result, and outputs it to the information output module; wherein the standard features are the MxA change features of non-complicated respiratory virus-infected individuals without complications.

[0055] In some embodiments, the information of the subject being examined further includes one or more of the subject's photo, age, gender, height, weight, eating habits, underlying diseases, immune status, medication history, mood status, time from symptom onset to medical treatment, family genetic history, smoking frequency and exercise type.

[0056] In some embodiments, the information output module outputs information through the main interface of the reporting system. The information displayed on the main interface of the reporting system may include one, multiple, or all of the following: 1). Invoke and display the information of the subject under examination in the specimen information receiving function module; 2). The function of recording and modifying date information; 3). Invoke and display the text template of the disease condition determination result, and provide the modification permission; 4). Printing of the report and establishment of a custom report template; the custom items include the subject number, report header, test value, reference value, report picture, health advice, reviewer, and printer. The date information may further include one or more of the following: sampling time, sample submission time, instrument detection date, user information entry date, date of receiving the instrument detection result, report review date, report printing date, and report sending date.

[0057] In some embodiments, the dynamic quantitative detection of MxA includes: detecting once every 12 - 24 hours during the acute phase and once every 48 - 96 hours during the convalescent phase.

[0058] In some embodiments, the standard features include: MxA increases on the day of respiratory virus infection, reaches the peak 1 - 2 days after infection, then gradually decreases, and decreases by up to 1 / 2 compared to the peak 1 week after infection, and stabilizes 8 - 12 days after infection and drops to 50 ng / ml or below.

[0059] In some embodiments, according to whether the MxA concentration reaches the peak and decreases regularly during monitoring, the disease condition of patients with respiratory virus infection is monitored.

[0060] In some embodiments, compared with the standard features, if the MxA level of an individual: ① remains at a high level or decreases slowly after reaching the peak; ② continues to increase; ③ decreases after reaching the peak and then abnormally increases again; if any of the above situations occur, the following content is output: It is necessary to be vigilant about at least one of the complications such as pneumonia / bronchitis, secondary respiratory bacterial / fungal infection, co - infection with other viruses, recurrence of respiratory virus infection, poor antiviral efficacy, and virus resistance.

[0061] Next, the embodiments of the present invention will be described in detail in conjunction with examples. It should be understood that these examples are only used to illustrate the present invention and not to limit the scope of the present invention. For the experimental methods without specific conditions indicated in the following examples, priority is given to the guidance given in the present invention, and it can also be carried out according to the experimental manuals or conventional conditions in the art, or other known experimental methods in the art, or the conditions recommended by the manufacturer.

[0062] In the following specific embodiments, regarding the measurement parameters of raw material components, unless otherwise specified, there may be slight deviations within the weighing accuracy range. Regarding temperature and time parameters, acceptable deviations caused by instrument test accuracy or operation accuracy are allowed.

[0063] Example 1 Description of the kinetic characteristics of MxA 1. Test subjects A total of 201 patients with uncomplicated acute respiratory virus infections in China-Japan Friendship Hospital from December 2023 to June 2024 were prospectively enrolled. First, patients with uncomplicated ARI were recruited. The patients needed to meet the following conditions simultaneously: ① At least two respiratory symptoms or signs: cough, sore throat, runny nose, nasal congestion, hoarseness, loss of smell; with or without fever; ② The onset time ≤ 7 days. Patients meeting any one or more of the following criteria were excluded: receiving interferon treatment within the past 30 days, having suffered major trauma / burns, major surgery, myocardial infarction, stroke within the past 30 days, or receiving any vaccine within the past 30 days.

[0064] On the recruitment day, the clinical data of all ARI patients meeting the inclusion and exclusion criteria were collected through a pre-prepared case report form, including the patient's gender, age, comorbidity status, onset date, and anti-infection treatment status. At the same time, etiological screening was carried out. Oropharyngeal swabs of the patients were collected and sent for targeted genomic sequencing (tNGS). Experienced respiratory clinicians interpreted the tNGS results. Patients with respiratory virus detected and clinically determined to have respiratory virus infection were included in the subsequent trial.

[0065] This study was confirmed and approved by the hospital ethics committee, and all study participants obtained written informed consent from themselves or their legal representatives.

[0066] 2. Test process and MxA detection All included patients with uncomplicated viral ARI were followed up 1 - 3 times. The follow-up time points were the day of enrollment, 4 (±2) days after enrollment, and 9 (±2) days after enrollment. 2 - 4 ml of peripheral venous blood of the patients was collected on each follow-up day. According to the specific implementation of the present invention and combined with the knowledge in the art, in the uses, diagnostic methods, or diagnostic products provided by the present invention above, the samples of the individuals mentioned are taken from, including but not limited to, the whole blood, plasma, or serum of the individuals. At the same time, symptom assessment was carried out. The respiratory symptoms recorded in the symptom assessment included: whether there were cough, nasal congestion or runny nose, sneezing, sore throat or dry throat, earache, dyspnea, headache, fever, chills or shivering, muscle or body pain (or soreness), fatigue or tiredness, nausea, chest pain, joint pain, vomiting, and diarrhea on the follow-up day, as well as the severity of the corresponding symptoms (0 - 3 points).

[0067] The collected peripheral blood samples were quantitatively detected for MxA. In the disclosed embodiments, the MxA detection was performed using a Q20 fully automatic immunoanalyzer (China Zhongyuan Huiji Co., Ltd.) in combination with a human myxovirus resistance protein A detection kit (dry immuno-fluorescence method) (China Zhongyuan Huiji Co., Ltd.) and a supporting diluent. According to the specific implementation of the present invention and combined with the knowledge in the art, in the uses, diagnostic methods or diagnostic products provided by the above invention, except for the above detection method, any method can be used to detect the content of MxA mRNA and / or protein.

[0068] 3. Statistical analysis Taking the symptom onset date (onset date) of the patient as Day 0, the actual course of the follow-up date from Day 0 is the actual course of the follow-up date. A scatter plot of time-MxA concentration changing with time since the onset date was drawn, and further, the MxA kinetic curve was fitted by a generalized additive model (gam) to calculate the MxA peak time and peak value of the fitted curve, and the time corresponding to MxA dropping to 50 ng / ml. At the same time, the scores of the symptoms on the follow-up date were added up and divided by the corresponding number of influenza / novel coronavirus symptoms to obtain the average symptom score on the follow-up date, and the correlation between MxA and the average symptom score was analyzed.

[0069] 4. Test results 4.1 Baseline characteristics The median age of the 201 included acute respiratory virus-infected patients was 33.5 (26.3 - 42.0) years old, 126 (62.7%) were female, and all patients had upper respiratory tract infections. The median onset time of the patients at the time of enrollment was 1.0 (1.0 - 3.0) days. Among them, 59 were infected with influenza A virus, 43 were infected with influenza B virus, 78 were infected with severe acute respiratory syndrome coronavirus 2, and the remaining 21 were infected with other viruses. 106 viral ARI patients were followed up only once on the day of enrollment, 58 completed 2 follow-ups, and 37 completed all 3 follow-ups.

[0070] 4.2 Description of MxA kinetic characteristics The kinetic characteristics of MxA in viral ARI patients without complications are shown in Figure 1 . MxA increased on the onset date (Day 0), then continued to increase, reached the peak value at about Day 2, then gradually decreased, dropped below 50 ng / ml at Day 10 and tended to be stable. 95 viral ARI patients were symptom-scored, and the average symptom score of the patients was highly correlated with the MxA concentration (p = 0.002).

[0071] Example 2 Clinical verification Seven viral ARI patients with complications or other changes in their conditions were included in the validation study. After enrollment, peripheral blood MxA was detected at least twice and compared with the normal MxA change pattern obtained in Example 1 to verify the ability of MxA to monitor changes in the condition.

[0072] Table 1 Test results of patients with respiratory virus infections complicated with complications

[0073] * ① Remaining at a high level continuously or decreasing slowly after reaching the peak; ② Continuing to increase; ③ Decreasing after reaching the peak and then abnormally increasing again.

[0074] Discussion In the prior art, C-reactive protein (CRP), procalcitonin (PCT), or interleukin-6 (IL-6) is often used as a biomarker to monitor the condition of respiratory infections. However, there are the following deficiencies Fuzzy dynamic characteristics: Although CRP may increase slightly (about 10 - 40 mg / L) in viral infections, the peak appearance time (3 - 5 days after onset) is significantly lagged behind the viral replication peak, and the decline is slow (it takes 14 - 21 days to return to normal), making it unable to accurately reflect early changes in the condition. PCT usually does not increase significantly in viral infections (<0.5 ng / ml), while although IL-6 increases in the acute phase, its half-life is short (about 1 hour), resulting in a drastic concentration fluctuation and a lack of a stable dynamic pattern.

[0075] Specificity defects: CRP / PCT is more sensitive to bacterial infections and is prone to false positives in viral-bacterial mixed infections (such as CRP > 100 mg / L in bacterial infections). As a broad-spectrum inflammatory factor, IL-6 is significantly interfered by non-infectious factors such as tumors and autoimmune diseases.

[0076] Limited clinical guidance value: Existing markers cannot establish a kinetic model synchronized with the change in viral load. Clinical data show that the correlation between CRP concentration and the time of negative conversion of respiratory virus nucleic acid is poor, resulting in its inability to be used for efficacy evaluation and drug resistance monitoring.

[0077] The MxA marker of the present invention is accurately and dynamically associated with viral replication. The MxA peak is synchronized with the viral replication peak (1 - 2 days after onset), and the concentration curve during the recovery period of 8 - 12 days highly coincides with the viral clearance process. Coupled with strong virus specificity, MxA is induced by type I / III interferons and has higher specificity in simple viral infections.

[0078] The above results indicate that in patients with uncomplicated respiratory virus infections, MxA exhibits characteristic dynamic changes, and its level is highly correlated with the severity of the patients' symptoms. When monitoring the MxA level in viral ARI patients with changing conditions, it can be observed that the change in their MxA level significantly deviates from the standard kinetic characteristics, and this abnormal change often indicates the evolution of the clinical condition. Based on these findings, we believe that by dynamically monitoring the MxA expression level in viral ARI patients and comparing its change trend with the standard characteristics, it is expected to effectively monitor the patients' conditions. This method can provide important reference bases such as early warning of the condition and prognosis assessment for clinical practice.

[0079] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims, and the description and the drawings can be used to explain the content of the claims.

Claims

1. Use of a quantitative detection agent for MxA in the preparation of a kit for monitoring the course of acute respiratory tract infection.

2. The use according to claim 1, wherein the quantitative detection agent comprises a reagent for detecting changes in MxA mRNA, and is applicable to at least one of the following methods: Sequencing, polymerase chain reaction (PCR), isothermal amplification reaction, resonance light scattering method, biomass spectrometry, electrochemical analysis, gel electrophoresis, capillary electrophoresis, microarray, CRISPR-Cas detection system.

3. The application according to claim 2, wherein The quantitative detection agent comprises a probe and / or primer capable of specifically binding to MxA mRNA or cDNA.

4. The application according to claim 1, characterized in that The quantitative detection agent comprises a reagent for detecting changes in MxA protein, and is applicable to at least one of the following detection methods: immunoassay, biomass spectrometry, lectin-based detection method, and aptamer-based detection method.

5. The application according to claim 4, wherein The quantitative detection agent is selected from: ELISA reagent, Western Blot reagent, immunofluorescence reagent or immunohistochemistry reagent.

6. The application according to any one of claims 1-5, characterized in that, The acute respiratory tract infection is a viral infection.

7. The application according to claim 6, wherein the pathogen of the viral infection includes: Influenza virus (preferably including influenza A virus and / or influenza B virus), coronavirus (preferably including human coronavirus, more preferably including severe acute respiratory syndrome coronavirus 2), rhinovirus, respiratory syncytial virus, metapneumovirus, adenovirus, and parainfluenza virus.

8. The use according to any one of claims 1-5, wherein the test sample of the kit is selected from: whole blood, serum or plasma; Optionally, the kit can also be used for at least one of efficacy prediction, prognosis prediction, guiding antiviral and antibiotic medication, and drug resistance prediction of acute respiratory tract infection.

9. An acute respiratory tract infection course monitoring system, the system comprising: A sample information processing module, a diagnosis module, and an information output module; The sample information module is used to receive the information of the subject to be tested with acute respiratory tract infection, and the information of the subject to be tested at least includes the dynamic quantitative detection result of MxA in the sample from the patient; The diagnosis module receives the information input from the sample information processing module, compares the dynamic changes of MxA with the standard features to obtain a monitoring result, and outputs it to the information output module; Wherein the standard features are the MxA change features of uncomplicated respiratory virus infected patients without complications.

10. The system according to claim 9, wherein the dynamic quantitative detection of MxA comprises: It is detected once every 12-24 hours in the acute phase and once every 48-96 hours in the recovery phase; Optionally, the standard features include: MxA increases on the day of respiratory virus infection, reaches a peak 1-2 days after infection, then gradually decreases, the decrease is up to 1 / 2 of the peak 1 week after infection, and tends to be stable 8-12 days after infection and drops to 50 ng / ml and below; Optionally, according to whether the MxA concentration reaches a peak and decreases regularly during monitoring, the condition of patients with respiratory virus infection can be monitored. Optionally, when comparing with the standard features, if the MxA level of an individual: ① remains at a high level or decreases slowly after reaching the peak; ② continuously increases; ③ decreases after reaching the peak and then abnormally increases again; if any of the above situations occur, the following content shall be output: Be vigilant about at least one of the following complications, including pneumonia / bronchitis, secondary respiratory bacterial / fungal infections, co-infection with other viruses, recurrence of respiratory virus infection, poor antiviral efficacy, and virus resistance.

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