CN108982876A - SAA1 detection agent is preparing the application in the kit for diagnosing Henoch Schonlein purpura nephritis - Google Patents

Abstract

The present invention relates to a kind of novel Henoch Schonlein purpura nephritis disease marker SAA1, and are applied to be studied.The present invention has found that the marker has notable difference in anaphylactoid purpura and thrombocytopenic purpura, Chronic Renal Impairment clinically experiments have shown that individual serum and the variation for urinating SAA1 have higher sensitivity and specificity for the diagnosis of Henoch Schonlein purpura nephritis.The present invention will provide a kind of new diagnostic means for clinical diagnosis anaphylactoid purpura (nephrosis), have certain potential clinical value in the treatment of auxiliary anaphylactoid purpura (nephrosis) and course of disease monitoring.

Description

The use of SAA1 detection agent in the preparation of the kit for diagnosing Henoch-Schonlein purpura nephritis application

technical field

The present invention relates to the field of medical diagnosis, in particular to the application of a SAA1 detection agent in the preparation of a kit for diagnosing Henoch-Schonlein Purpura Nephritis.

Background technique

Henoch-Schonlein purpura (HSP) is an inflammatory disease involving small blood vessels throughout the body. Clinically, it mainly manifests as involvement of the skin, gastrointestinal tract, joints, and kidneys, and may also involve the brain, lungs, and scrotum. The pathological features are characterized by immunoglobulin A (immunoglobulin A, IgA)-based immune complex deposition (immunofluorescence) on the small blood vessel walls of the affected organs, and allergic purpura nephritis (Henoch-Schonlein purpuranephritis, HSPN) It refers to renal parenchymal damage caused by allergic purpura. Clinically, hematuria and/or proteinuria can be diagnosed as allergic purpura nephritis during the course of allergic purpura (including within 6 months of the onset of allergic purpura).

At present, it is believed that infections, poisons and drugs may be important causes of Henoch-Schonlein Purpura. Children often have upper respiratory tract infection 1-3 weeks before the onset of Henoch-Schonlein Purpura. Pathogens that may be related to the disease include parvovirus B19, hepatitis B virus, Hepatitis C virus, adenovirus, β-hemolytic streptococcus, Staphylococcus aureus, and mycoplasma; insect bites, clarithromycin and other poisons and drugs may be related to the onset of allergic purpura in adults.

Although the specific pathogenesis of Henoch-Schonlein Purpura and Henoch-Schonlein Purpura Nephritis is still unclear, many studies have provided a lot of data for further exploring the pathogenesis. Abnormal chain region glycosylation, complement activating cytokines and autoantibodies.

Human serum amyloid A protein (SAA) is an acute phase response protein, which belongs to the heterogeneous protein in the apolipoprotein family, with a molecular weight of about 12000. In the acute phase response, stimulated by IL-1, IL-6 and TNF, SAA is synthesized in the liver by activated macrophages and fibroblasts, which can increase to 100-1000 times the initial concentration, but the half-life Short, only about 50 minutes. Previous studies have confirmed that the SAA family consists of four family members: SAA1, SAA2, SAA3 and SAA4. As the main component of the family, SAA1 is the subtype with the most widespread expression, the strongest activity and the most sensitive response in the SAA family. Although the expression level of SAA1 is low under normal conditions, its serum concentration increases 1000-fold in a very short period of time in the acute phase. No significant correlation between SAA1 and Henoch-Schonlein purpura nephritis has been found in the prior art.

Contents of the invention

The invention relates to a novel allergic purpura nephritis disease marker, and its application is studied.

In order to realize the above-mentioned purpose of the present invention, special adopt following technical scheme:

The invention relates to the application of a SAA1 detection agent in preparing a kit for diagnosing Henoch-Schonlein purpura nephritis.

According to one aspect of the present invention, the present invention also relates to the application of the SAAl detection agent in the preparation of a kit for distinguishing acute kidney injury from chronic kidney injury.

According to one aspect of the present invention, the present invention also relates to the application of the SAA1 detection agent in the preparation of a kit for distinguishing allergic purpura nephritis from thrombocytopenic purpura nephritis.

The present invention proves that the changes of individual serum and urine SAA1 have high sensitivity and specificity for the diagnosis of Henoch-Schonlein Purpura Nephritis in clinical experiments, and it is found that the marker is effective in Henoch-Schonlein Purpura, Thrombocytopenic Purpura, and Chronic Kidney Injury have obvious differences. The invention will provide a new diagnostic method for clinical diagnosis of Henoch-Schonlein Purpura (nephrosis), and has certain potential clinical value in assisting the treatment of Henoch-Schonlein Purpura (Kidney disease) and monitoring the disease course.

Description of drawings

In order to more clearly illustrate the specific implementation of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the specific implementation or description of the prior art. Obviously, the accompanying drawings in the following description The drawings show some implementations of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any creative work.

Fig. 1 is the mRNA expression situation of SAA1, SAA2, SAA3, SAA4 in different populations in one embodiment of the present invention;

Fig. 2 shows the protein expression level of SAA1 in different populations in one embodiment of the present invention.

Detailed ways

The invention relates to the application of the SAA1 detection agent in preparing a kit for diagnosing Henoch-Schonlein purpura nephritis (especially acute nephritis combined with diabetes infection).

Preferably, as described above, the kit is used to detect body fluids of subjects.

Preferably, the above application, wherein the body fluids include peripheral blood, serum, plasma, sputum, synovial fluid, aqueous humor, amniotic fluid, milk, semen, prostatic fluid, sweat, urine, tears, cystic fluid, pleural effusion fluid, ascitic fluid, pericardial fluid, chyle, bile, interstitial fluid, menstrual blood, pus, vomitus, vaginal discharge, mucous membrane secretion, pancreatic juice, bronchopulmonary aspirated fluid, blastocoel fluid, or umbilical cord blood.

Preferably, the above-mentioned application, wherein the body fluid includes peripheral blood, serum, plasma, and urine.

Preferably, in the above-mentioned application, the kit further includes one or more detection reagents for biomarkers of Henoch-Schonlein Purpura Nephritis.

Preferably, in the above-mentioned application, the allergic purpura nephritis biomarker is selected from urinary podocyte and its related marker protein (PCX), monocyte chemoattractant protein-1 (MCP-1), macrophage motility Inhibitor factor (MIF), neutrophil gelatinase-associated protein (NGAL), urinary transforming growth factor β1 (TGF-β1), tumor necrosis factor-α (TNF-α), MPO myeloperoxidase, Toll-like Receptor 4 (TLR4), superoxide dismutase (SOD), pentraxin 3 (PTX3), insulin-like growth factor 1 (IGF-1), epidermal growth factor (EGF), urinary protein.

Preferably, as described above, the urine protein includes albumin (ALB), immunoglobulin G (IgG), soluble transferrin (Soluble transferrin receptor, sTfR), Tamm-Horsafll protein, retinol binding protein .

Preferably, in the above-mentioned application, the SAA1 detection agent includes an anti-SAA1 antibody; or; qPCR primers and/or probes for detecting SAA1 mRNA.

The SAA1 detection reagent can be used with any known quantitative or semi-quantitative protein/mRNA detection methods, such as westernblot, qPCR, ELISA, flow cytometry and so on.

The term "antibody" includes polyclonal antibodies and monoclonal antibodies, as well as antigenic compound-binding fragments of these antibodies, including Fab, F(ab')2, Fd, Fv, scFv, bispecific antibodies, and antibody minimal recognition units, as well as these antibody and single-chain derivatives of fragments. The type of antibody can choose IgG1, IgG2, IgG3, IgG4, IgA, IgM, IgE, IgD. Furthermore, the term "antibody" includes naturally occurring antibodies as well as non-naturally occurring antibodies including, for example, chimeric, bifunctional, and humanized antibodies, and related synthetic isomeric forms (isoforms). The term "antibody" is used interchangeably with "immunoglobulin".

According to one aspect of the present invention, the present invention also relates to the preparation of SAA1 detection agent for distinguishing acute kidney injury (especially acute allergic purpura nephritis with diabetes infection) and (especially chronic allergic purpura nephritis with diabetes infection) ) application in the kit for chronic kidney injury.

According to one aspect of the present invention, the present invention also relates to the application of the SAA1 detection agent in the preparation of a kit for distinguishing allergic purpura nephritis (especially complicated with diabetes infection) from thrombocytopenic purpura nephritis.

Embodiments of the present invention will be described in detail below in conjunction with examples, but those skilled in the art will understand that the following examples are only for illustrating the present invention, and should not be considered as limiting the scope of the present invention. Those who do not indicate the specific conditions in the examples are carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used were not indicated by the manufacturer, and they were all commercially available conventional products.

Example 1iTRAQ Screens Differential Proteins

Part I. Screening of urine molecular markers of renal injury

1. Main experimental materials:

Urine of patients with renal impairment (diabetic AKI patients, AKI+CKD patients, diabetic CKD patients, non-diabetic CKD patients with IgA, non-diabetic non-IgA CKD patients, 50 cases each); healthy people (50 cases); iTRAQ kit.

2. Experimental setup:

2.1 Early detection and inclusion criteria for patients with kidney disease

2.1.1 AKI inclusion criteria (clinical diagnosis)

According to the following two criteria, as the inclusion criteria of early AKI (AKI stage I): the blood creatinine content increased by 26.2 μmol/L within 48 hours or increased to 1.5-1.9 times the baseline value; the urine output was less than 6 hours continuously (not exceeding 12 hours) 0.5ml/Kg/h.

2.1.2 AKI+CKD (CKD-based AKI patients, that is, CKD complicated with AKI) inclusion criteria (clinical diagnosis)

According to the clinical detection indicators, it is judged whether the patient is an AKI+CKD patient.

2.1.3 CKD inclusion criteria (clinical diagnosis)

Serum creatinine was detected (enzyme method), and the glomerular filtration rate (GFR) was calculated according to the formula. When the GFR was in the range of (45-59) ml/min/1.73m2, the patient was an early CKD (CKD 3A) patient.

Then according to whether the patient has diabetes, IgA nephropathy, etc., it can be judged which type of CKD patient the patient belongs to.

Simplified MDRD formula: GFR (ml/min/1.73m2) = 186 × [Scr (mg/dL)] - 1.154 × age - 0.203 × 0.742 (female).

Sample provision method: Patient sample: 50ml of fresh mid-morning urine (increased to 150ml for normal person samples), divided into 10ml/tube, add 1ml of protease inhibitor per 10ml of urine, 4000rpm, 4 degrees, centrifuge for 10 minutes, then centrifuge Afterwards, the supernatant was transferred to a 15ml cryopreservation tube and stored at -80°C. The sample concentration was completed by our company.

2.2 Detection of protein types and contents in various early renal injuries

2.2.1 Experimental grouping (6 groups)

Mixed urine samples from 50 patients with acute kidney injury (AKI);

Mixed urine samples from 50 patients with AKI+CKD;

Mixed urine samples from 50 diabetic patients with chronic kidney damage (CKD);

Pooled urine samples from 50 CKD patients with non-diabetic IgA;

Mixed urine samples from 50 non-diabetic and non-IgA CKD patients;

Pooled urine samples from 50 healthy individuals.

Each group, 3 parallel. (Three biological repetitions, that is, urine samples of 150 patients in each group are required)

2.2.2 iTRAQ combined with LC-MS/MS technology for protein identification and content analysis (6 groups × 2 times)

1. Sample preparation, enrichment and storage: Take 50ml of fresh mid-morning urine from patients and healthy subjects, immediately cool to 4°C, centrifuge at 2000g for 20min, take the supernatant, and use urine from patients with the same disease or healthy subjects Mix and store in a -80°C refrigerator, or directly perform subsequent operations. After the urine is thawed, use acetone precipitation to extract protein;

2. Determination of protein concentration: use BCA method to determine protein concentration;

3. Proteolysis and iTRAQ labeling;

4. Use the combination of liquid chromatography and mass spectrometry to perform primary mass spectrometry analysis;

5. Perform secondary mass spectrometry analysis;

6. Database retrieval and bioinformatics analysis, identification of protein types, and analysis of expression content.

2.3 Primary screening of potential urine markers

2.3.1 First Screening

1. Compare the protein type and content in the mixed urine samples of AKI patients and healthy people, and screen out the abnormally expressed proteins in AKI patients;

2. Compare the protein type and content in the mixed urine samples of AKI+CKD patients and healthy people, and screen out the abnormally expressed proteins in AKI+CKD patients;

3. Compare the protein type and content in the mixed urine samples of diabetic CKD patients and healthy subjects, and screen out the abnormally expressed proteins in diabetic CKD patients;

4. Compare the protein type and content in the mixed urine samples of CKD patients with non-diabetic IgA and the mixed urine samples of healthy subjects, and screen out the abnormally expressed proteins in CKD patients with early non-diabetic IgA;

5. Compare the protein type and content in the mixed urine samples of non-diabetic non-IgA CKD patients and healthy subjects, and screen out the abnormally expressed proteins in early non-diabetic non-IgA CKD patients.

2.3.2 Second Screening

1. According to the results of 2.3.1, compare the types and contents of proteins in the urine of patients with non-diabetic CKD (including IgA and non-IgA CKD), and screen out proteins that are abnormally expressed in non-diabetic CKD, and proteins that are only expressed in certain types of non-diabetic CKD. Proteins abnormally expressed in diabetic kidney injury (i.e. proteins abnormally expressed only in non-diabetic IgA CKD patients, proteins abnormally expressed only in non-diabetic non-IgA CKD patients);

2. According to the results of 2.3.1 and 2.3.2.1 (proteins abnormally expressed in all types of non-diabetic kidney injury), compare the protein types and Content, to screen out proteins that are abnormally expressed in both diabetic CKD and non-diabetic CKD, and proteins that are specifically abnormally expressed in various types of CKD (that is, proteins that are abnormally expressed only in diabetic CKD, and abnormally expressed only in non-diabetic CKD protein);

3. According to the results of 2.3.1 and 2.3.2.2 (proteins abnormally expressed in all types of CKD), compare AKI, CKD+AKI, and CKD (diabetic CKD, non-diabetic IgA CKD, non-diabetic non-IgA CKD) patients The type and content of protein in urine, screen out the proteins that are abnormally expressed in all kinds of kidney injuries, and the proteins that are only differentially expressed in certain types of kidney injuries (that is, the proteins that are only differentially expressed in AKI, and only in CKD+ Differentially expressed proteins in AKI, only aberrantly expressed in CKD).

2.3.3 The third screening

1. According to the results of 2.3.2.3 and 2.3.1, screen out the proteins that are only abnormally expressed in the urine of AKI patients and the proteins that are only abnormally expressed in the urine of AKI+CKD patients;

2. Based on the results of 2.3.2.2 and 2.3.1, screen out proteins that are abnormally expressed only in diabetic CKD and proteins that are only abnormally expressed in non-diabetic kidney injury;

3. According to the results of 2.3.2.1 and 2.3.1, screen out proteins that are abnormally expressed only in non-diabetic IgA CKD, and proteins that are only abnormally expressed in non-diabetic non-IgA CKD.

RESULTS: Screened for shared potential urinary markers of renal injury, screened for AKI-specific potential urine markers, screened for AKI+CKD-specific potential urine markers, screened for shared specific potential urine markers for CKD , to screen out diabetic CKD-specific potential urine markers, to screen out non-diabetic CKD-common specific potential urine markers, to screen out non-diabetic CKD-specific potential urine markers for non-diabetic IgA, to screen out non-diabetic non-IgA CKD-specific potential urinary markers.

2.4 Biological function analysis of potential urine markers

Use databases, bioinformatics software and analysis methods to analyze the correlation and possible effects (proliferation, apoptosis, survival, inflammation, repair, migration, etc.) So as to judge the possible role and possible molecular mechanism of these potential urine markers in renal injury.

The PEIMAP method was used to analyze the interaction between urine proteins and other proteins.

1. Use BOND (http://bond.unleashedinformatics.com/), DIP (http://dip.doe-mbi.ucla.edu/dip), MINT (http://mint.bio.uniroma2.it/ mint/), IntAct (http://www.ebi.ac.uk/intact/), HPRD (http://www.hprd.org/), meta core, Ingenuity PathwayAnalysis, Drosophila (http://www .fruitfly.org/) Arabidopsis (http://www.arabidopsis.org/), rice (http://gene64.dna.affrc.go.jp/RPD/), slime mold (http://dictybase .org/) and software such as NCBI Blast, predict protein interaction principles based on "homology" (that is, if two proteins in one species interact, then in other species, the homology of these two proteins Proteins should also interact), so as to analyze the possible interacting proteins of urine markers.

2. Based on the literature and the above results, functionally classify these proteins that may interact with urinary proteins, such as proliferation (cyclins: CyclinD, CylinE, etc.; cyclin-dependent kinases: CDK1, CDK2, etc.; cyclin-dependent Sex kinase inhibitors: p21, p53, etc.; and other proliferation regulators), apoptosis (Bax, Bcl-2, p53, Caspase family, Survivin, etc.), interstitial fibrosis (matrix metalloproteinases MMPs and their inhibitors TIMPs , collagen, cytoskeleton-related proteins and signaling molecules, etc.), oxidative stress, etc.

3. According to the protein function classification and the results of 2.3.1, analyze the possible role and molecular mechanism of potential urine proteins.

Embodiment 2 is related to the result of SAA1

According to the protein expression abundance, when the protein difference multiple is greater than 1.2 (up-regulated) or less than 0.83 (down-regulated) and p<0.05, it is screened as a differential protein. The differential proteins screened out in each group were sorted according to the multiple of difference, and the top 10 differential proteins in each group were selected.

Among them, SAA1 protein was abnormally expressed in the urine of AKI patients with diabetes mellitus, and the up-regulation times were more than 2.4 times, but there was no significant change in CKD patients with diabetes mellitus.

Based on this, the protein of interest was screened and verified by molecular biology.

Example 3SAA1 is a potential marker of Henoch-Schonlein Purpura (HSP) nephritis

1. Main experimental materials:

Hematuria (HSP group, AKI type, 50 cases) and kidney biopsy samples (7 cases) in patients with HSP renal injury complicated with diabetes infection; hematuria in HSP renal injury patients without diabetes (HSP-non-diabetic group, AKI type, 30 cases) ;Co-infected with diabetes; Chronic kidney injury (CKD) crowd urine (50 cases) and kidney puncture samples (8 cases); Thrombocytopenic purpura (ITP) renal injury patients urine (AKI type, 50 cases) and kidney puncture samples Samples (7 cases); urine from healthy people (50 cases). All specimens were collected with the informed consent of the patients and signed informed consent forms.

2. Urine specimen collection:

The hematuria samples of Henoch-Schonlein Purpura Nephritis group, Chronic Kidney Injury and Thrombocytopenic Purpura group were collected in the early morning of the second day after the patients were admitted to the hospital, and the hematuria samples of healthy people were collected when the patients visited the doctor. Among them, 5ml of urine and 5m of blood were reserved respectively. The collected urine was centrifuged at 3000r/min for 10 minutes, and the supernatant was taken, distributed into 200uL EP tubes, and frozen at -80°C for later use; the collected blood , centrifuge at 3000r/min for 10 minutes, take the supernatant serum, dispense it into 200uL EP tubes, and freeze at -80°C for later use;

3. Experimental method:

3.1 Real-time quantitative PCR (qPCR)

1) Use the Trizol method to extract RNA from kidney biopsy samples.

2) Real-time quantitative PCR reaction system

A total of 20ul system, centrifuge <2000rbpm with tray after adding the sample.

2) Primer sequence:

3) Reaction conditions:

SAA1 reaction conditions:

95℃30s

95℃0s

62℃5s (annealing temperature)

72℃10s

40 cycles

95℃0s

65℃30s

95℃0.1/continuous cooling

40℃30s

The annealing temperatures of SAA2, SAA3 and SAA4 were 64°C, 63°C and 62°C, respectively, and the other reaction conditions were the same as those of SAA1.

The experimental results are shown in Figure 1. Among them, only the expression of SAA1 mRNA in the HSP group changed significantly (p<0.05, vs CKD population). The rest of the groups did not change. In order to further verify the feasibility of SAA1 as an HSP biomarker from the protein level, the inventors then conducted further verification from the protein level.

3.2 Western blot

1) Protein extraction: protein extracted from kidney biopsy samples.

2) Measuring protein concentration: the specific steps are the same as ELISA.

3) Western blot

①Glue compounding: choose glue with a concentration of 10% according to the molecular weight of the protein.

Upper glue formula:

30% acrylamide 6.67 double distilled water 8.10 1.5M Tris 8.8 5.0 20% SDS 0.1 10%APS 0.1 TEMED 34μl total capacity 20ml

Underlayer glue formula:

30% acrylamide 1.67 double distilled water 5.68 0.5M Tris 6.8 2.5 20% SDS 0.05 10%APS 0.1 TEMED 10μl total capacity 10ml

Prepare the upper and lower layers at the same time, add water, acrylamide, 1.5M Tris, 10% APS, 20% SDS, and finally add TEMED.

②Add sample

③Electrophoresis: After adding the sample, run steady-flow electrophoresis. The current of one gel is 32mA, and the voltage will slowly rise to about 99V (after about 1h) to stop. The gel running time can also be automatically adjusted according to the molecular weight of the protein to be tested.

④Transfer film, the constant voltage is 100-120V (110v) when transferring film, the specific steps are as follows:

After the PVDF membrane is activated in methanol, it is washed in water, and after sinking, it is put into the transfer solution.

Use the transfer tank, add the transfer liquid, put the splint black under it, put the sponge, three layers of filter paper, glue, PVDF membrane, three layers of filter paper and sponge in sequence. Stack neatly, use a roller to remove air bubbles, press them tightly and place them in the transfer film tank, and mark the corners of the film.

The transfer time is determined by the molecular weight of the protein, which is about 2 hours.

⑤Blocking of PVDF membrane: After transfer, block with 5% BSA in blocking solution for 1 hour to remove non-specific binding.

⑥Primary antibody incubation: Pour off the blocking solution, add Anti-SAA1 Antibody Clone B333A (dilutewith 5% BSA, 1:3000), and incubate overnight at 4°C.

⑦Wash with TBST 3x 10min.

⑧Secondary antibody incubation:

SAA1 secondary antibody: anti-Human 1:5000, in 5% BSA

Room temperature 1h.

⑨Wash 3x 10min with TBST.

⑩ After 5 minutes of color development in the chromogenic solution, the tablet was pressed in a dark room.

The film was statistically analyzed with Image J software, and the change of SAA1 was measured by the change of the ratio of SAA1 to tubulin (internal reference).

3.3ELISA

(1) Protein extraction: Add protein lysate (TNE: PMSF, NaF, Na3VO4, Leupeptin 1:100) to the urine sample at a ratio of 1:10, turn over and mix on a silent suspension for 2 hours, and take after centrifugation. supernatant.

(2) Determination of protein concentration (refer to the instructions of the BCA kit):

①Calculate the amount of BCA needed, prepare the mixed solution according to a certain ratio (MA:MB:MC=25:24:1), add 150ul for each, add 150ul for standard A-I, and make duplicate holes when adding samples.

②Because the standard substance is dissolved in 0.9% NaCl, first dilute the sample to be tested with 0.9% NaCl and load 150ul of the sample. The sample to be tested also needs to be duplicated.

③Use a microplate reader to shake for 5 seconds to mix the sample, and then place it in a 37°C incubator for 2 hours.

④ Take it out of the incubator at 37°C, measure the absorbance value of the protein with a microplate reader after cooling down, and calculate the protein concentration.

(3) Adding samples: Add 100ul of standard or sample to be tested when there is no space in the 96-well plate, and incubate at 37°C for 2h.

(4) Washing: wash 4-6 times with washing liquid.

(5) Antigen-antibody reaction: Add 100ul of antibody working solution to each well, and incubate at 37°C for 1h.

(6) After sufficient washing, add 100ul of enzyme-labeled antibody and incubate at 37°C for 30min.

(7) After washing away excess antibody, add 100ul of substrate working solution to each well, and incubate at 37°C for 15min.

(8) Terminate the reaction, and measure the absorbance with a microplate reader within 30 min.

The results are shown in the table below:

The SAA1 of the present invention is used for HSP detection, has very good sensitivity, and can be well distinguished from CKD, ITP and healthy people.

It should be noted that at last: above each embodiment is only in order to illustrate technical scheme of the present invention, and is not intended to limit; Although the present invention has been described in detail with reference to foregoing each embodiment, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. range.

Claims (10)

1. The application of the SAA1 detection agent in the preparation of a kit for diagnosing Henoch-Schonlein Purpura Nephritis. 2. The application according to claim 1, characterized in that the kit is used to detect body fluids of subjects. 3. The application according to claim 1, wherein the body fluids include peripheral blood, serum, plasma, sputum, synovial fluid, aqueous humor, amniotic fluid, milk, semen, prostatic fluid, sweat, urine, tears , cyst fluid, pleural effusion, ascites fluid, pericardial fluid, chyle, bile, interstitial fluid, menstrual blood, pus, vomit, vaginal secretion, mucosal secretion, pancreatic juice, bronchopulmonary aspiration fluid, blastocoel fluid or cord blood. 4. The application according to claim 3, wherein the body fluid includes peripheral blood, serum, plasma, and urine. 5. The application according to claim 1, wherein the kit further comprises one or more detection reagents for biomarkers of Henoch-Schonlein Purpura Nephritis. 6. The application according to claim 5, wherein the allergic purpura nephritis biomarker is selected from urinary podocytes and related marker proteins, monocyte chemoattractant protein-1, macrophage migration inhibitory factor , neutrophil gelatinase-associated transporter protein, urinary transforming growth factor β1, tumor necrosis factor-α, MPO myeloperoxidase, Toll-like receptor 4, superoxide dismutase, pentraxin 3, insulin-like Growth factor 1, epidermal growth factor, urinary protein. 7. The application according to claim 6, wherein the urine protein comprises albumin, immunoglobulin G, soluble transferrin, Tamm-Horsafll protein, retinol binding protein. 8. The application according to claim 1, wherein the SAAl detection agent comprises an anti-SAA1 antibody; or; qPCR primers and/or probes for detecting SAAl mRNA. 9. Application of the SAA1 detection agent in preparing a kit for distinguishing acute kidney injury from chronic kidney injury. 10. The application of the SAA1 detection agent in the preparation of a kit for distinguishing allergic purpura nephritis from thrombocytopenic purpura nephritis.