Application of HNL in preparation of reagent for identifying blood flow infection

Abstract

The invention relates to an application of HNL in preparation of a reagent for identifying blood flow infection, belongs to the field of precision medical treatment, and provides an application of HNL in a detection kit for diagnosing whether a patient has blood flow infection or not, and the patient is chronic hepatitis B cirrhosis. The detection kit is used for diagnosing whether bacterial blood flow infection exists or not by detecting whether the HNL content level in a blood, plasma or serum sample taken from a patient exceeds a set cut-off value or not; the bacterial blood flow infection diagnosis of chronic hepatitis B cirrhosis combined with special primary diseases is accidentally realized through the HNL, and the sensitivity of 90.6% and the specificity of 100% of the diagnosis result are in an excellent level, so that the HNL has a relatively high clinical value and a relatively high industrial prospect.

Description

Technical Field

[0001] The present invention relates to the field of precision medicine, specifically to the field of disease diagnosis biomarkers, and particularly to the use of HNL in preparing reagents for identifying bloodstream infections. Background Art

[0002] Human neutrophil lipocalin (HNL) is a secretory glycoprotein stored in the secondary granules of neutrophils, and is the main component of the secondary granules of neutrophils. In the field of bacterial infection detection, the HNL described in the industry usually refers specifically to the 45-KD homodimer of HNL. The present invention also follows this industry practice, that is, the HNL in the present invention specifically refers to the HNL45-KD homodimer. Since neutrophils involved in the acute bacterial infection process specifically secrete HNL45-KD homodimers, it has high sensitivity and specificity for diagnosing bacterial infections. In addition, the 25-KD monomer form of HNL widely used in clinical practice is called NGAL, which is mainly produced by renal tubular epithelial cells. When the kidneys are damaged or diseased, the renal tubular epithelial cells release a large amount of NGAL into the urine or blood, making it an early and sensitive renal injury marker, and then the content of NGAL in urine or blood can be detected to assist in judging whether the kidneys are damaged or diseased and the progression of the disease. The monomeric form of NGAL can also polymerize with MMP-9, which is highly expressed in tumor patients, to form a 135-KD heterodimer. Therefore, some studies have also used the detection and analysis of changes in the content of this heterodimer to assist in determining and monitoring the progression of tumor disease in patients.

[0003] When human peripheral blood neutrophils are stimulated and activated, HNL can be released from the cell to the outside of the cell. When acute bacterial infection occurs, the concentration of HNL in the blood can increase significantly within 1-2 hours. HNL can further induce the release of granules in leukocytes, chemotactic aggregation of inflammatory cells, and eliminate pathogenic microorganisms, showing anti-inflammatory and antibacterial effects in inflammatory injuries.

[0004] In view of the mechanism of action of HNL, HNL has been developed as a biomarker for diagnosis of sepsis, inflammation, etc. The corresponding disease is diagnosed by detecting the level of HNL in individual serum and other samples and comparing it with the HNL level of normal people.

[0005] For example, the PCT international patent application with publication number WO9529404A1 provides the use of HNL as a biomarker for diagnosing human inflammation, especially inflammation caused by bacterial infection. WO9529404A1 further discloses that the HNL level in the serum of healthy people is 37.95-190.87 μg / L, and three critical values ​​of 190 μg / L, 155 μg / L and 100 μg / L are set to distinguish between patients with viral infection and bacterial infection. Among them, when the critical value is set at 155 μg / L, the sensitivity and specificity are relatively acceptable.

[0006] SYXu et al. (SYXu et al. The development of an assay for humanneutrophit lipocalin (HNL) to be used as a specific marker of neutrophilactivity in vivo and in vitro. Journal of Immunological Methods 171 (1994) 245-252) also established a method for determining the content of biomarker HNL by RIA. They disclosed that the HNL level in serum and plasma of healthy people was 37.95-190.87 μg / L (average level 78.4 μg / L), among which the HNL level in plasma was 30.51-105.8 μg / L (average level 50.65 μg / L). The HNL content level in serum was significantly higher than that in plasma.

[0007] Based on the research disclosed in the aforementioned literature, China has approved and marketed medical device products for HNL detection, such as JMJ No. 20162400304. Its main intended use involves clinical applications such as assisting in the early diagnosis of bacterial infection or sepsis, and differential diagnosis of bacterial and viral infections. The product manual states that the normal reference value for diagnosis is ≤115.55 ng / mL.

[0008] However, so far, the detection and diagnostic application of HNL is still based on the level of healthy people. The reason is that it is still unclear whether and how the presence of primary diseases affects the concentration of HNL. Related primary diseases may add additional burden to the immune system, and different types of primary diseases have different effects on the burden of the immune system. Therefore, at this time, compared with the HNL content level after bacterial infection in the patient group without related primary diseases, the average level of HNL content in the patient group with related primary diseases after bacterial infection may increase as a whole, may decrease as a whole, or may show irregular and unstable HNL content levels in some patients, decrease in some patients, and maintain the same level of HNL content as that in the patient group without related primary diseases after bacterial infection. Therefore, under such complex influences, if the diagnosis of bacterial infection is still carried out according to the cut-off value standard of healthy people, it is very likely that the diagnosis result of "false negative" or "false positive" will appear. What's more, in such patients, the HNL concentration is extremely unstable, so that it cannot be used in such patients. A typical example is patients with concomitant blood diseases. Since HNL in the blood is secreted by neutrophils, the level of HNL is directly related to the number of neutrophils. Such primary diseases can cause extremely abnormal numbers of neutrophils, seriously affecting the blood concentration of HNL. Therefore, the instructions for use of diagnostic kits that have been approved for marketing, such as Jiji No. 20162400304, also have similar reminders such as "When neutropenia is complicated by infection, HNL does not increase or only increases slightly due to reduced release" to clarify the limitations of the marketed HNL detection kit in the diagnosis of bacterial infections combined with primary diseases. This also further reflects the complexity and unpredictability of using HNL as a biomarker to diagnose bacterial infections in patients with concurrent primary diseases.

[0009] The liver of patients with cirrhosis has been damaged to varying degrees and has associated immune deficiencies, which are related to factors such as severe damage to the patient's reticuloendothelial system, complement system defects, T lymphocyte and B lymphocyte defects, immunoglobulin and macrophage phagocytic function defects, etc. The immune deficiencies in patients with cirrhosis are prone to systemic inflammatory reactions such as granulocytopenia and reduced immunity due to the entry of various pathogens into the body's blood system. Once a bacterial bloodstream infection occurs, the bacteria continue to multiply in the blood, producing a large amount of toxins, causing extensive tissue damage, and in severe cases, threatening the patient's life.

[0010] Almost all patients with cirrhosis are accompanied by leukopenia, which further seriously affects the changes in the blood concentration of HNL, and then affects the accuracy of diagnosis of bloodstream infection in patients with cirrhosis with primary diseases using HNL as a biomarker. A specific example is that in the preliminary study of the present invention, the HNL detection kit approved by the Food and Drug Administration (Ji Xie Zhu Zhu 20162400304) was used to diagnose whether patients with cirrhosis have bacterial bloodstream infection. According to the cut-off value of 115.55 ng / ml provided in the instructions of the kit as the critical value for diagnosis, the sensitivity is extremely poor, and almost more than 86% of patients with cirrhosis bloodstream infection are "false negative" and misdiagnosed as non-infected people.

[0011] However, more than that, for patients with primary cirrhosis, the diagnosis of bloodstream infection using HNL as a biomarker faces greater challenges. As mentioned above, compared with the HNL content level after bacterial infection in the group of patients with cirrhosis without related primary diseases, the average level of HNL content in the group of patients with primary cirrhosis after bacterial infection may increase or decrease as a whole, or it may show irregular and unstable HNL content levels of some patients, some patients decrease, and some patients maintain the same level of HNL content as the group of patients with cirrhosis without related primary diseases after bacterial infection. Based on this, given the uncertainty of the change of the overall HNL content level after bacterial bloodstream infection in the group of patients with cirrhosis, it is not feasible and the diagnostic effect cannot be expected to simply adjust the cut-off value to apply the diagnosis of bloodstream infection in the group of patients with cirrhosis according to conventional thinking.

[0012] In summary, how to diagnose bloodstream infection in patients with cirrhosis at an early stage with high specificity and sensitivity, so as to provide more targeted clinical treatments such as antibiotics and avoid the occurrence of septic shock, is a very urgent clinical need. Summary of the invention

[0013] In order to meet the urgent and unmet clinical needs, the present invention provides the use of the biomarker HNL in diagnosing the presence of bacterial bloodstream infection in a patient population with a specific combined primary disease type, and the specific combined primary disease type is specifically specified as chronic hepatitis B cirrhosis. On this basis, the present invention also provides a series of related uses and corresponding HNL detection kits.

[0014] The first aspect of the present invention provides the use of HNL or its specific binder in the preparation of a detection reagent for distinguishing whether a subject has a bacterial bloodstream infection, wherein the subject is a patient with chronic hepatitis B cirrhosis; the cut-off value of the detection reagent in the detection reaction is 50-59 ng / mL.

[0015] Furthermore, the differentiation is performed by detecting whether the HNL content level in the test sample taken from the subject's body fluid sample exceeds a set cut-off value to diagnose whether there is a bacterial bloodstream infection.

[0016] Furthermore, it is characterized in that the cut-off value of the detection is 54-56 ng / mL, preferably 55 ng / mL.

[0017] Furthermore, the body fluid sample taken from the subject is blood, serum, plasma, preferably serum.

[0018] Furthermore, the specific binding substance is an antibody or antibody fragment that specifically binds to HNL.

[0019] Furthermore, the detection reagent is used for a detection method such as electrophoresis, immunofluorescence, direct competition, indirect competition, ELISA, RIA, flow cytometry or immunochromatography; preferably, ELISA or colloidal gold immunochromatography.

[0020] The second aspect of the present invention is to provide the use of HNL or its specific binding compound in the preparation of a detection reagent for determining the severity of bacterial bloodstream infection for determining whether a subject has bacterial bloodstream infection, wherein the subject is a patient with chronic hepatitis B cirrhosis, and the detection reagent determines the severity of bacterial bloodstream infection by detecting how much the HNL content level in a body fluid sample taken from the subject exceeds a set cut-off value, and the cut-off value of the detection is 50~59ng / mL.

[0021] Furthermore, it is characterized in that the cut-off value of the detection is 54-56 ng / mL, preferably 55 ng / mL.

[0022] Furthermore, the body fluid sample taken from the subject is blood, serum, plasma, preferably serum.

[0023] Furthermore, the specific binding substance is an antibody or antibody fragment that specifically binds to HNL.

[0024] Furthermore, the detection reagent is used for a detection method such as electrophoresis, immunofluorescence, direct competition, indirect competition, ELISA, RIA, flow cytometry or immunochromatography; preferably, ELISA or colloidal gold immunochromatography.

[0025] The third aspect of the present invention is to provide the use of HNL or its specific binding substance in the preparation of a detection reagent for evaluating the prognosis of antibiotic treatment for bacterial bloodstream infection in a subject, wherein the subject is a patient with chronic hepatitis B cirrhosis, and the detection reagent diagnoses the presence of bacterial bloodstream infection by detecting that the HNL content level in a body fluid sample taken from the subject before antibiotic treatment exceeds a set cut-off value, and the cut-off value of the detection kit is 50-59 ng / mL; and the detection reagent evaluates the treatment prognosis of the administered antibiotic by re-detecting the HNL content level in the body fluid sample taken from the subject after antibiotic treatment, and comparing it with the HNL content level detection result of the patient before antibiotic treatment.

[0026] Further, it is characterized in that the cut-off value of the detection is 54~56 ng / mL, preferably 55ng / mL.

[0027] Furthermore, the body fluid sample taken from the subject is blood, serum, plasma, preferably serum.

[0028] Furthermore, the specific binding substance is an antibody or antibody fragment that specifically binds to HNL.

[0029] Furthermore, the detection reagent is used for a detection method such as electrophoresis, immunofluorescence, direct competition, indirect competition, ELISA, RIA, flow cytometry or immunochromatography; preferably, ELISA or colloidal gold immunochromatography.

[0030] The fourth aspect of the present invention is to provide an HNL detection kit, characterized in that the detection kit comprises a binder that specifically binds to HNL, a standard substance and a buffer, and a warning line mark, wherein the warning line mark includes a detection result pattern corresponding to when the HNL content of the sample is a cut-off value; the warning line mark also includes a prominent and eye-catching mark corresponding to the detection result when the HNL content of the sample is greater than 50~59ng / mL.

[0031] Furthermore, the kit is used for detection by electrophoresis, immunofluorescence, direct competition, indirect competition, ELISA, RIA, flow cytometry or immunochromatography; preferably, ELISA or colloidal gold immunochromatography; Furthermore, the warning line mark also includes a prominent and eye-catching mark corresponding to the test result when the HNL content of the sample is greater than 54-56 ng / mL.

[0032] Furthermore, the warning line mark also includes a prominent and eye-catching mark corresponding to the test result when the HNL content of the sample is greater than 55 ng / mL.

[0033] The beneficial effects of the present invention include: The present invention applies HNL for the first time to the detection and differentiation of bacterial bloodstream infection in chronic hepatitis B cirrhosis, providing effective support for the subdivided treatment of the disease and the evaluation of treatment effects. Specifically, the detection reagent diagnoses whether there is a bacterial bloodstream infection by detecting whether the HNL content level in the blood, plasma or serum sample taken from the patient exceeds the set cut-off value. The present invention unexpectedly achieves the diagnosis of bacterial bloodstream infection in chronic hepatitis B cirrhosis with special primary diseases through HNL, and the diagnostic results have a sensitivity of 90.6% and a specificity of 100%, both of which are at an excellent level, and have great clinical value and industrial prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A data analysis curve chart showing whether 71 patients with chronic hepatitis B cirrhosis have bacterial bloodstream infection, where A is the ROC curve and B is the data analysis. DETAILED DESCRIPTION

[0035] The following is a further description of the concept of the present invention and the technical effects produced in conjunction with specific embodiments, so as to fully understand the purpose, features and effects of the present invention. The methods are conventional methods unless otherwise specified. The materials can be obtained from public commercial channels unless otherwise specified. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations of the present invention. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

[0036] Example 1 Experimental study on the detection of bloodstream infection in patients with non-hepatitis B cirrhosis using HNL levels Unless otherwise specified, the reagents and drugs used in the test examples described in the present invention are all common commercial products. The instruments used are also common equipment and instruments in the industry. The specific means of clinical experiments not listed are also carried out with reference to relevant national standards and common practices in the industry. These will not be described in detail one by one in the present invention.

[0037] The HNL detection kit used in the test examples described in the present invention can be purchased through ordinary commercial channels, for example, it can be directly obtained through ordinary commercial channels from Ubos (Zhejiang) Biotechnology Co., Ltd. The HNL detection kit used in the test examples described in the present invention can also be obtained by conventional preparation methods in the industry or by reference to the preparation methods disclosed in the relevant prior art literature, for example, it can be prepared by the method described in the Chinese invention patent application with application number CN202310712274.2. In the specific implementation of the test examples described in the present invention, the HNL detection kit used is obtained through ordinary commercial channels from Ubos (Zhejiang) Biotechnology Co., Ltd.

[0038] 1. Subjects: A total of 46 patients with non-hepatitis B cirrhosis (including hepatitis C cirrhosis, autoimmune cirrhosis and alcoholic cirrhosis) were randomly selected from the Department of Infectious Diseases of the Second Affiliated Hospital of Chongqing Medical University.

[0039] 2. Test methods: 1) The HNL test kit was used to test the serum HNL levels of 46 patients with non-hepatitis B cirrhosis. The HNL test results are recorded in Table 1 below.

[0040] 2) Blood culture, the clinical gold standard for diagnosing bloodstream infection, was used as a means (combined with the patient's chronic liver disease history, symptoms, signs, and laboratory tests such as hepatitis B and C virus markers, autoimmune liver disease markers, blood routine, C-reactive protein, procalcitonin test, etc.), assisted by imaging liver MRI and liver CT examinations. A variety of clinical routine methods, laboratory tests such as liver and kidney function, myocardial markers, brain damage markers, blood culture, urine culture and stool culture were used to clinically diagnose the condition of 46 patients with non-hepatitis B cirrhosis to determine whether their actual condition had bloodstream infection, and the clinical diagnosis results were recorded in Table 1 below.

[0041] 3) Combined with the clinical diagnosis results of each case in Table 1 by conventional means, a statistical analysis was performed on the HNL detection concentration results shown in Table 1.

[0042] Table 1

[0043] 3. Result analysis: Statistical Table 1 Data: For this special group of patients with concurrent primary disease other than hepatitis B and cirrhosis, there was no statistically significant difference between the two groups of data in the HNL test results for distinguishing and diagnosing bloodstream infection and non-bloodstream infection.

[0044] Even if 50 ng / mL is set as the diagnostic threshold (cut-off value), only 7 of the 21 patients with non-HBV cirrhosis who were clinically diagnosed with bloodstream infection were correctly diagnosed after HNL testing, with a calculated sensitivity of 33.3%. Among the 25 patients with non-HBV cirrhosis who were clinically diagnosed with non-bloodstream infection, only 19 were correctly diagnosed after HNL testing, with a calculated specificity of 76%. Its sensitivity and specificity, especially the sensitivity, cannot meet clinical needs.

[0045] Example 2: Test of using HNL levels to detect bloodstream infection in patients with hepatitis B cirrhosis 1. Experimental subjects A total of 71 patients with chronic hepatitis B cirrhosis from the Department of Infectious Diseases of the Second Affiliated Hospital of Chongqing Medical University were randomly selected.

[0046] 2. Test methods and results 1) The HNL detection kit was used to detect the serum HNL levels of 71 patients with chronic hepatitis B cirrhosis. The HNL content was 55 ng / mL as the diagnostic threshold. If the test results showed that the HNL content in the individual sample was greater than the above diagnostic threshold, it was marked as bloodstream infection. If the HNL content in the individual sample was not greater than the above diagnostic threshold, it was marked as non-bloodstream infection.

[0047] The HNL test results and the diagnostic marker results with 55 ng / mL as the diagnostic threshold are recorded in Table 2 below.

[0048] 2) Blood culture, the clinical gold standard for diagnosing bloodstream infection, was used as a means (combined with the patient's chronic liver disease history, symptoms, signs, and laboratory tests such as hepatitis B and C virus markers, autoimmune liver disease markers, blood routine, C-reactive protein, procalcitonin test, etc.), assisted by imaging liver MRI and liver CT examinations. A variety of clinical routine methods, laboratory tests such as liver and kidney function, myocardial markers, brain damage markers, blood culture, urine culture and stool culture were used to clinically diagnose the condition of 71 patients with chronic hepatitis B cirrhosis to determine whether their actual condition had bloodstream infection, and the clinical diagnosis results were recorded in Table 2 below.

[0049] 3) Compare and contrast the diagnostic marker results of the HNL detection kit shown in Table 2 with the clinical diagnosis results of conventional means, and statistically analyze the detection sensitivity and specificity.

[0050] Table 2

[0051] 3. Results Analysis Statistics Table 2 data: 32 patients with chronic hepatitis B cirrhosis were clinically diagnosed with bloodstream infection, of which 29 were correctly diagnosed and marked after HNL testing; 39 patients with chronic hepatitis B cirrhosis were clinically diagnosed without bloodstream infection (non-bloodstream infection), of which 39 were correctly diagnosed and marked after HNL testing.

[0052] The data in Table 2 were statistically analyzed and we obtained Figure 1The results shown in A were analyzed by SPSS software, and 55 ng / mL was used as the diagnostic threshold (cut-off value), which can well identify chronic hepatitis B cirrhosis. For all 71 patients with chronic hepatitis B cirrhosis, the sensitivity and specificity of HNL detection in distinguishing and diagnosing hemorrhage infection were 90.6% and 100%, respectively, and the AUC was 0.97 ( Figure 1 B), outperforms current methods.

[0053] Therefore, unlike patients with non-hepatitis B cirrhosis, for this special group of patients with chronic hepatitis B cirrhosis and concurrent primary disease, using HNL as a biomarker to identify bloodstream infection has an excellent diagnostic detection effect and outstanding clinical value.

[0054] Preparation Example: Preparation of HNL Detection Kit for Diagnosing Bacterial Bloodstream Infection in Patients with Chronic Hepatitis B Cirrhosis The basic composition and structure of the HNL detection kit of this preparation example can be obtained by the conventional preparation method in the industry or by referring to the preparation method disclosed in the relevant prior art literature, for example, it can be prepared by the method described in the Chinese invention patent application with application number CN202310712274.2.

[0055] The detection method that can be used in the HNL detection kit of this preparation example is electrophoresis, immunofluorescence, direct competition, indirect competition, ELISA, RIA, flow cytometry or immunochromatography. ELISA or colloidal gold immunochromatography is usually preferred.

[0056] In particular, the HNL detection kit of this preparation example includes a reference cut-off value, and the cut-off value is 55 ng / mL.

[0057] For the convenience of clinical use, a warning line mark for HNL chronic hepatitis B cirrhosis bloodstream infection can be further designed on the HNL detection kit of this preparation example, and the warning line mark can be, for example, a test result pattern corresponding to a sample HNL content of 55 ng / mL. In another specific preparation example, the warning line mark also includes a prominent and eye-catching mark corresponding to the test result when the sample HNL content is 55 ng / mL.

[0058] Another use of the HNL detection kit of this preparation example can be, for example, to determine the severity of bacterial bloodstream infection in patients with chronic hepatitis B cirrhosis who have bacterial bloodstream infection. The detection kit determines the severity of bacterial bloodstream infection by detecting how much the HNL content level in the blood, plasma or serum sample taken from the patient exceeds the set cut-off value.

[0059] Another use of the HNL detection kit of this preparation example can be, for example, to evaluate the prognosis of antibiotic treatment in patients with chronic hepatitis B cirrhosis who have bacterial bloodstream infection. The detection kit diagnoses the presence of bacterial bloodstream infection by detecting that the HNL content level in the blood, plasma or serum sample taken from the patient before antibiotic treatment exceeds a set cut-off value, and the cut-off value of the detection kit is 55 ng / mL; and the detection kit evaluates the treatment prognosis of the administered antibiotics by again detecting the HNL content level in the blood, plasma or serum sample taken from the patient after antibiotic treatment and comparing it with the HNL content level detection result of the patient before antibiotic treatment.

[0060] The test examples and embodiments involved in the above specific implementation methods are merely descriptions of the preferred implementation methods of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. Use of HNL or its specific binding substance in the preparation of a detection reagent for distinguishing whether a subject has a bacterial bloodstream infection, characterized in that: The subjects are patients with chronic hepatitis B cirrhosis; the cut-off value of the detection reagent in the detection is 50~59ng / mL.

2. The use according to claim 1, characterized in that The differentiation is performed by detecting whether the HNL content level in the test sample taken from the subject's body fluid sample exceeds a set cut-off value to diagnose whether there is a bacterial bloodstream infection.

3. The use according to claim 1, characterized in that The cut-off value of the detection was 54~57 ng / mL.

4. Use of HNL or its specific binding substance in the preparation of a detection reagent for determining whether a subject has a bacterial bloodstream infection and the severity thereof, characterized in that: The subject is a patient with chronic hepatitis B cirrhosis. The detection reagent determines the severity of bacterial bloodstream infection by detecting how much the HNL content level in the body fluid sample taken from the subject exceeds the set cut-off value. The cut-off value of the detection is 54~57 ng / mL.

5. Use of HNL or its specific conjugate in the preparation of a detection reagent for evaluating the prognosis of antibiotic treatment for bacterial bloodstream infection in a subject, characterized in that: The subject is a patient with chronic hepatitis B cirrhosis, and the detection reagent diagnoses the presence of bacterial bloodstream infection by detecting that the HNL content level in the body fluid sample taken from the subject before antibiotic treatment exceeds a set cut-off value, and the cut-off value of the detection kit is 50-59 ng / mL; and the detection reagent evaluates the treatment prognosis of the administered antibiotics by re-detecting the HNL content level in the body fluid sample taken from the subject after antibiotic treatment and comparing it with the HNL content level detection result of the patient before antibiotic treatment.

6. The use according to claim 5, characterized in that The cut-off value is 54~56ng / mL.

7. The use according to any one of claims 1 to 6, characterized in that: The cut-off value is 55 ng / mL.

8. The use according to any one of claims 1 to 6, characterized in that: The specific binding substance is an antibody or antibody fragment that specifically binds to HNL.

9. The use according to any one of claims 2, 4 to 5, characterized in that: The body fluid sample to be tested is taken from the serum sample of the subject.

10. A HNL detection kit, characterized in that: The detection kit comprises a binder that specifically binds to HNL, a standard substance, a buffer, and a warning line mark, wherein the warning line mark comprises a detection result pattern corresponding to when the HNL content of the sample is a cut-off value; the warning line mark also comprises a prominent and eye-catching mark corresponding to the detection result when the HNL content of the sample is greater than 54-56 ng / mL.

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