Systemic lupus erythematosus molecular diagnosis marker based on neutrophil characteristics

Abstract

The invention discloses a systemic lupus erythematosus molecular diagnosis marker based on neutrophil characteristics. The invention provides application of a substance for detecting the expression quantity of an IFIH1 gene and / or a CFLAR gene in preparation of a product for auxiliary diagnosis or screening or auxiliary screening of systemic lupus erythematosus. The invention also provides an application of a substance for detecting the relative expression quantity of the IFIH1 gene and the CFLAR gene and a carrier loaded with the following combined index C value model formula in preparation of a product for auxiliary diagnosis or screening or auxiliary screening of systemic lupus erythematosus. The specific gene expression marker IFIH1 and / or CFLAR of the neutrophile granulocyte is selected by focusing the unique change of the SLE neutrophile granulocyte to assist the clinical early-stage identification and diagnosis of the SLE, and an IFIH1 and CFLAR combined diagnosis model is constructed, so that the diagnosis or screening of the SLE is realized; the kit has high sensitivity and specificity.

Description

Technical Field

[0001] The invention belongs to the field of biotechnology and relates to molecular diagnostic markers for systemic lupus erythematosus based on neutrophil characteristics. Background Art

[0002] Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by dysregulation of the body's immune tolerance, production of autoantibodies, formation and deposition of immune complexes, leading to tissue and organ damage. The incidence of SLE is gradually increasing. There are about 1 million SLE patients in my country, mainly in women of childbearing age. SLE has a low clinical remission rate, high disability and mortality rates, and a cumulative mortality rate of up to 20% in 15 years, which imposes a serious economic burden on families and society. SLE has a diverse clinical phenotype, with multiple and severe organ involvement, often involving multiple systems such as the kidneys, cardiovascular system, skin, central nervous system, blood system, and respiratory system. The incidence of SLE in my country is about three times that of the European and American population, and Chinese SLE patients develop at an earlier age, with more complex and diverse clinical symptoms, and are more likely to develop lupus nephritis.

[0003] At present, although great progress has been made in the diagnosis and treatment of SLE, since the initial symptoms of SLE patients are diverse and their clinical manifestations overlap with other common diseases, its diagnosis usually takes a long time. Therefore, it is necessary to develop new indicators to assist in early screening in order to achieve the purpose of early diagnosis and treatment.

[0004] Evaluation of gene expression patterns is considered a valuable tool that can provide important details for a better understanding of the pathogenic mechanisms of a variety of diseases. Peripheral blood represents the major immune cell pool of tissue / organ-infiltrating immune cells. The global immune dysregulation commonly observed in SLE can be reflected by distinct changes in the composition and transcriptional status of peripheral immune cells. Traditional gene expression analysis of SLE has been performed by transcriptome profiling of whole peripheral blood, which revealed a SLE type I interferon (IFN-I) signature. However, granulocytes are the most abundant type of circulating leukocytes and often cause “transcriptome noise” to mask gene expression differences in other immune cells. To circumvent this problem, large transcriptomic analyses or more recently single-cell RNA sequencing (scRNA-seq) of SLE and RA have focused on peripheral blood mononuclear cells (PBMCs) or tissue-infiltrating monocytes. However, this technique may have largely overlooked the role of neutrophils in the pathogenesis of these diseases. Summary of the invention

[0005] The purpose of the present invention is to provide molecular diagnostic markers for systemic lupus erythematosus based on neutrophil characteristics.

[0006] In a first aspect, the present invention provides the use of a substance for detecting the expression level of the IFIH1 gene and / or the CFLAR gene in the preparation of a product for auxiliary diagnosis or screening or auxiliary screening of systemic lupus erythematosus.

[0007] In a second aspect, the present invention provides the use of a substance for detecting the expression of the IFIH1 gene and the CFLAR gene and a carrier loaded with the following model formula in the preparation of a product for auxiliary diagnosis or screening or auxiliary screening of systemic lupus erythematosus;

[0008] The model formula:

[0009] C = 29.657*a+5.906*b-4.266,

[0010] Where C is the combined index C value, a is the expression level of IFIH1 gene, and b is the expression level of CFLAR gene.

[0011] The above gene expression levels are relative expression levels.

[0012] The above-mentioned person to be examined may be a patient suspected of having systemic lupus erythematosus.

[0013] In the above first aspect or the first aspect,

[0014] The substance for detecting the expression level of the IFIH1 gene and / or the CFLAR gene is any one of the following:

[0015] 1) comprising a primer pair for amplifying the IFIH1 gene and / or the CFLAR gene;

[0016] 2) A PCR reagent or kit containing the primer pair.

[0017] The above-mentioned 1) material for detecting the expression level of IFIH1 gene and / or CFLAR gene also includes amplification primers of the internal reference gene GAPDH;

[0018] The above-mentioned IFIH1 gene or CFLAR gene expression levels are all relative expression levels of IFIH1 or CFLAR genes, specifically, the Ct value of the target gene (IFIH1 or CFLAR) minus the Ct value of the internal reference gene (GAPDH) to obtain the ΔCt value; then 2 –ΔCt It was recorded as the relative expression level of the target gene.

[0019] In a third aspect, the present invention provides a kit for assisting in the diagnosis of systemic lupus erythematosus, comprising the substance for detecting the expression levels of the IFIH1 gene and the CFLAR gene in the first or second aspect.

[0020] The above-mentioned kit also includes a carrier loaded with the following model formula;

[0021] The model formula is C=29.657*a+5.906*b-4.266, wherein C is the combined index C value, a is the IFIH1 gene expression level, and b is the CFLAR gene expression level.

[0022] In a fourth aspect, the present invention provides a device for assisting in the diagnosis of systemic lupus erythematosus, comprising a data acquisition module, a threshold acquisition module, a judgment module and an output module;

[0023] The data acquisition module is used to obtain the expression level A of the IFIH1 gene or the CFLAR gene in the peripheral blood neutrophils of the subject;

[0024] The threshold value acquisition module is used to take the critical value at the maximum value of the Youden index in the ROC curve of the expression of the IFIH1 gene or the CFLAR gene in the systemic lupus erythematosus group to the control group as the threshold value B;

[0025] The above thresholds are derived from a training set, which consists of m systemic lupus erythematosus patients (specifically 46 patients in one embodiment) and n controls (55 patients in one embodiment, including 22 healthy subjects and 33 disease controls).

[0026] The judgment module is used to compare the expression amount A with the threshold value B to obtain a judgment result, which is specifically as follows:

[0027] If the expression amount A is greater than the threshold value B, the subject is judged to be or is a candidate for being a systemic lupus erythematosus patient;

[0028] If the expression amount A is less than or equal to the threshold value B, it is determined that the subject is not or is not a candidate for a systemic lupus erythematosus patient;

[0029] The output module is used to output the judgment result obtained by the judgment module.

[0030] In one embodiment, the expression level A of the IFIH1 gene or the CFLAR gene in peripheral blood neutrophils is obtained by real-time fluorescence quantitative PCR detection.

[0031] In a fifth aspect, the present invention provides a device for assisting in the diagnosis of systemic lupus erythematosus, comprising a data acquisition module, a threshold acquisition module, a judgment module and an output module;

[0032] The data acquisition module is used to obtain the expression levels of the IFIH1 gene and the CFLAR gene in the peripheral blood neutrophils of the subject, and then calculate the combined index C value through a model formula; the model formula is as follows: C=29.657*a+5.906*b-4.266, where C is the combined index C value, a is the expression level of the IFIH1 gene, and b is the expression level of the CFLAR gene;

[0033] The threshold value acquisition module is used to draw a ROC curve of the combined index C value of the systemic lupus erythematosus group to the control group, and take the critical value at the maximum value of the Youden index as the threshold D;

[0034] The above control group includes healthy subjects and / or disease control patients.

[0035] The above thresholds are derived from a training set, which consists of m systemic lupus erythematosus patients (specifically 46 patients in one embodiment) and n controls (55 patients in one embodiment, including 22 healthy subjects and 33 disease controls).

[0036] The judgment module is used to compare the combined index C value with the threshold D to obtain a judgment result, which is as follows:

[0037] If the combined index C value is greater than the threshold D, the subject is judged to be or is a candidate for being a systemic lupus erythematosus patient;

[0038] If the combined index C value is less than or equal to the threshold D, it is determined that the subject is not or is not a candidate for a systemic lupus erythematosus patient.

[0039] The output module is used to output the judgment result obtained by the judgment module.

[0040] In a sixth aspect, the present invention provides a product for assisting in the diagnosis of systemic lupus erythematosus, comprising the substance for detecting the expression level of IFIH1 gene and / or CFLAR gene in the first or second aspect, the kit in the third aspect, or the device in the fourth or fifth aspect.

[0041] In the seventh aspect, the present invention provides the use of the substance for detecting the expression level of IFIH1 gene and / or CFLAR gene described in the first or second aspect, the kit described in the third aspect, or the device described in the fourth or fifth aspect in the preparation of a product for auxiliary diagnosis of systemic lupus erythematosus.

[0042] Beneficial effects of the present invention: The present invention focuses on the unique changes of SLE neutrophils, selects neutrophil-specific gene expression markers IFIH1 and / or CFLAR, assists in the clinical early differential diagnosis of SLE, and constructs a model for the combined diagnosis of IFIH1 and CFLAR, thereby achieving auxiliary diagnosis or screening of SLE; it has high sensitivity and specificity. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 The expression levels of IFIH1 and CFLAR genes in systemic lupus erythematosus, rheumatoid arthritis and healthy controls are different.

[0044] Figure 2This is the ROC curve of the IFIH1 gene or CFLAR gene in the training set systemic lupus erythematosus group versus the control group.

[0045] Figure 3 These are the gene expression results of IFIH1 and CFLAR in the training set and validation set.

[0046] Figure 4 The combined index C value of the systemic lupus erythematosus group versus the control group in the training set and validation set (left figure) and the ROC curve of the combined index C value of the training set (right figure). DETAILED DESCRIPTION

[0047] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0048] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0049] The characteristics of the case samples in the following embodiments are shown in Table 1:

[0050] Table 1 shows the basic characteristics of the disease group, healthy control group and disease control group included in the study

[0051]

[0052] Note: Systemic lupus erythematosus refers to patients who have been clinically diagnosed according to the diagnostic classification criteria for systemic lupus erythematosus (SLE) jointly issued by the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR) in 2019; the healthy control group (HCs) included healthy volunteers with normal indicators in the physical examination center; the disease control group (DCs) included patients who were clearly diagnosed according to the diagnostic criteria for various diseases, including 10 cases of rheumatoid arthritis, 10 cases of connective tissue disease, 3 cases of systemic sclerosis, 6 cases of antiphospholipid syndrome, 9 cases of Sjögren's syndrome and 7 cases of novel coronavirus infection.

[0053] Example 1. Discovery of IFIH1 and CFLAR genes as markers for diagnosis of systemic lupus erythematosus and establishment of methods

[0054] 1. Discovery of IFIH1 and CFLAR genes as markers for diagnosis of systemic lupus erythematosus

[0055] The inventors previously analyzed the peripheral blood neutrophil transcriptomes of 14 patients with systemic lupus erythematosus, 15 patients with rheumatoid arthritis and 13 healthy subjects (population information is shown in Table 2).

[0056] Table 2 shows the basic characteristics of systemic lupus erythematosus, rheumatoid arthritis and healthy controls

[0057]

[0058] *p value compares the difference between SLE and healthy controls

[0059] #p value comparing the differences between SLE and RA patient groups

[0060] Through differential analysis, the expression of interferon-stimulated genes and cell death-related genes in patients with systemic lupus erythematosus was significantly increased. The inventors screened out two genes, IFIH1 and CFLAR, from interferon-stimulated genes and cell death-related genes through bioinformatics analysis methods and machine learning algorithms. The gene expressions of these genes were significantly different between systemic lupus erythematosus, rheumatoid arthritis and healthy controls (e.g. Figure 1 shown).

[0061] From the above, it can be seen that the expression levels of IFIH1 gene or CFLAR gene in healthy people, disease control group and systemic lupus erythematosus patients are significantly different, indicating that IFIH1 gene or CFLAR gene can be used to assist in the diagnosis of systemic lupus erythematosus patients.

[0062] 2. Establishment of a method for single gene diagnosis of systemic lupus erythematosus

[0063] 1. Extract RNA from the subjects' peripheral blood neutrophils and reverse transcribe to obtain cDNA.

[0064] The details are as follows:

[0065] 1) Collect 2 ml of peripheral EDTA anticoagulated blood from subjects (including clinically confirmed systemic lupus erythematosus patients, healthy controls and disease controls);

[0066] 2) Add 2 ml of Ficoll / Hypaque liquid (GE Healthcare) to a 15 ml clean centrifuge tube, tilt the centrifuge tube 45 degrees, slowly add the anticoagulated blood sample along the tube wall with a pipette to form a clear boundary line with the Ficoll liquid, tighten the lid, put the entire tube into a horizontal rotor centrifuge, and centrifuge at 1440 rpm (slow rise and slow fall) at room temperature for 20 minutes;

[0067] 3) Take out the centrifuge tube and carefully remove the upper plasma, buffy coat and Ficoll separation solution in turn with a pipette;

[0068] 4) Carefully add 600 μl of 20% polydextrose solution along the tube wall, tighten the tube cap, and slowly invert to mix for 5 minutes;

[0069] 5) Carefully add 4 ml of phosphate buffered saline (PBS) along the tube wall, tighten the tube cap, slowly invert and mix for 5 minutes, and let stand at room temperature for 20 minutes;

[0070] 6) When the liquid in the tube settles to a clear dividing line, use a pipette to carefully draw the upper clear liquid into another 15 ml clean centrifuge tube, add 10 ml of PBS, tighten the tube cap, gently invert to mix, put the whole tube into a horizontal rotor centrifuge, and centrifuge at 1500 rpm (fast rise and fall) at room temperature for 5 minutes;

[0071] 7) Use a pipette to remove the upper layer of liquid, leaving the cell pellet at the bottom of the tube, slowly add 3 ml of ACK red blood cell lysis buffer along the tube wall, slowly resuspend the cell pellet with a pipette, and let it stand at room temperature for 5 minutes;

[0072] 8) Carefully add 10 ml of PBS along the tube wall, tighten the tube cap, gently invert to mix, put the entire tube into a horizontal rotor centrifuge, and centrifuge at 1500 rpm (fast rise and fall) at room temperature for 5 minutes;

[0073] 9) Use a pipette to remove the upper layer of liquid, leaving the cell pellet at the bottom of the tube, carefully add 700 μl of TRIzol solution along the tube wall to resuspend the cell pellet, collect it into a 1.5 ml EP tube, and let it stand at room temperature for 5 minutes;

[0074] 10) Carefully add 700 μL of anhydrous ethanol to the EP tube, cover the tube tightly, and mix by inversion for 2 minutes;

[0075] 11) Use column extraction (Direct-zol TM mRNA was extracted using RNA MiniPrep (ZYMO RESEARCH) and kept on ice.

[0076] 12) Using the TAKARA reverse transcription kit, 20 μl of the mRNA obtained above was reverse transcribed into cDNA.

[0077] 2. Detection of relative expression of IFIH1 gene or CFLAR gene

[0078] Using the cDNA obtained in 1 above as a template, IFIH1 and CFLAR as target genes, GAPDH as an internal reference gene, and primers designed for real-time fluorescence quantitative PCR, the relative expression level of the IFIH1 gene or the CFLAR gene in the subject was obtained; specifically as follows:

[0079] Using PowerUp TM SYBR TMGreen Master Mix (Thermo Fisher Scientific) was used for real-time fluorescence quantitative PCR experiments, using IFIH1 (Forward 5'-TCACAAGTTGATGGTCCTCAAGT-3' sequence 1, Reverse 5'-CTGATGAGTTATTCTCCATGCCC-3' sequence 2), CFLAR (Forward 5'-TGCTCTTTTTGTGCCGGGAT-3' sequence 3, Reverse 5'-CGACAGACAGCTTACCTCTTTC-3' sequence 4) and GAPDH (Forward 5'-GGAGCGAGATCCCTCCAAAAT-3' sequence 5, Reverse 5'-GGCTGTTGTCATACTTCTCATGG-3' sequence 6) as primers, and three replicate wells were prepared for each well, and the conditions in the product manual were followed.

[0080] The experimental results are based on 2 –ΔΔCt The analysis was performed by the following method: a. The average Ct value of three parallel experiments for each gene in each sample was taken; b. The Ct value of the target gene (IFIH1 or CFLAR) of each sample was subtracted from the Ct value of the internal reference gene (GAPDH) to obtain the ΔCt value; c. The relative expression level of the target gene was 2 –ΔCt .

[0081] 3. Determination of threshold and judgment criteria

[0082] The subjects shown in Table 1 were used as test samples, including 71 patients with clinically confirmed systemic lupus erythematosus (also referred to as test samples) and 74 control group patients (including 29 healthy controls and 45 disease controls).

[0083] All samples were randomly divided into training set and validation set in a ratio of 7:3. The training set included 46 patients with SLE and 55 control patients (22 healthy patients and 33 disease controls), and the validation set included 25 patients with SLE and 19 control patients (7 healthy patients and 12 disease controls).

[0084] The threshold was determined according to the relative expression levels of the IFIH1 gene and the CFLAR gene of each sample in the training set. Specifically, the relative expression levels of the IFIH1 gene or the CFLAR gene of the systemic lupus erythematosus group in the training set and the control group were plotted against each other using an ROC curve, and the critical value at the maximum value of the Youden index was taken as the threshold.

[0085] ROC curve Figure 2 As shown, it can be seen that the threshold value of the relative expression level of the IFIH1 gene is 0.1070; the threshold value of the relative expression level of the CFLAR gene is 0.3895.

[0086] If the relative expression level of the subject's IFIH1 gene or CFLAR gene is greater than a threshold, the subject is or is a candidate for being a systemic lupus erythematosus patient; if the relative expression level of the subject's IFIH1 gene or CFLAR gene is less than or equal to the threshold, the subject is not or is not a candidate for being a systemic lupus erythematosus patient.

[0087] Example 2: Application in diagnosis of systemic lupus erythematosus

[0088] 1. Detection

[0089] The subjects shown in Table 1 were used as test samples, including 71 patients with clinically confirmed systemic lupus erythematosus (also referred to as test samples) and 74 control group patients (including 29 healthy controls and 45 disease controls).

[0090] All samples were randomly divided into training set and validation set in a ratio of 7:3. The training set included 46 patients with SLE and 55 control patients (22 healthy patients and 33 disease controls), and the validation set included 25 patients with SLE and 19 control patients (7 healthy patients and 12 disease controls).

[0091] The detection was carried out according to the method of Example 1.

[0092] The results of IFIH1 and CFLAR gene expression in the training set and validation set of the samples shown in Table 1 are as follows Figure 3 As shown, it can be seen that no matter in the training set or the validation set, the relative expression levels of the IFIH1 gene or the CFLAR gene in patients with systemic lupus erythematosus and the control patients are significantly different, which further confirms that these two genes can be used as diagnostic markers for patients with systemic lupus erythematosus.

[0093] 2. Sensitivity and specificity testing

[0094] The ROC curve was drawn using the IFIH1 gene expression levels and CFLAR gene expression levels of each SLE patient and control group in the training set. The critical value at the maximum Youden index was taken as the threshold, and diagnostic predictions were made for the training set and validation set samples, respectively, and their respective sensitivity, specificity, positive predictive value, and negative predictive value were calculated.

[0095] The results are shown in Tables 3 and 4, which list the diagnostic sensitivity, specificity, positive predictive value and negative predictive value respectively. It can be seen that the expression of the IFIH1 gene or the CFLAR gene alone can be used as a marker to assist in the diagnosis of patients with systemic lupus erythematosus with high sensitivity and specificity.

[0096] Table 3 shows the sensitivity, specificity, positive predictive value and negative predictive value of the IFIH1 gene

[0097]

[0098] Table 4 shows the sensitivity, specificity, positive predictive value and negative predictive value of CFLAR gene

[0099]

[0100]

[0101] Example 3: Combined diagnosis of systemic lupus erythematosus

[0102] 1. Joint diagnosis model formula

[0103] It can be seen from the above Examples 1 and 2 that the relative expression of the IFIH1 gene or the CFLAR gene alone can be used to assist in the diagnosis of patients with systemic lupus erythematosus. In order to further study whether the combined diagnosis of the two can improve the diagnostic efficiency, a combined diagnosis model formula was constructed based on the results of the training set:

[0104] C = 29.657*a+5.906*b-4.266,

[0105] Where C is the combined index C value, a is the relative expression level of the IFIH1 gene, and b is the relative expression level of the CFLAR gene.

[0106] The relative expression of the above IFIH1 or CFLAR gene is 2 –ΔCt , where the ΔCt value is the Ct value of the target gene (IFIH1 or CFLAR) minus the Ct value of the internal reference gene (GAPDH).

[0107] 2. Establishment of a dual-gene diagnosis method for systemic lupus erythematosus

[0108] 1. The same as 1 in Example 1, to obtain cDNA;

[0109] 2. The same as 2 in Example 1, the relative expression level of the IFIH1 gene and the relative expression level of the CFLAR gene are obtained;

[0110] 3. Substitute the relative expression levels of the target gene IFIH1 and the target gene CFLAR obtained in 2 above into the following joint diagnosis model formula to calculate the joint index C value.

[0111] C = 29.657*a+5.906*b-4.266,

[0112] Where C is the combined index C value, a is the relative expression level of the IFIH1 gene, and b is the relative expression level of the CFLAR gene.

[0113] The ROC curve was drawn based on the combined index C value of the systemic lupus erythematosus group in the training set and the control group ( Figure 4 ), taking the critical value at the maximum value of the Youden index, and obtaining the threshold of the joint index C value as 0.1535.

[0114] If the subject's combined index C value is greater than the threshold, the subject is or is a candidate for being a systemic lupus erythematosus patient. If the subject's combined index C value is less than or equal to the threshold, the subject is not or is not a candidate for being a systemic lupus erythematosus patient.

[0115] 3. Application of dual gene diagnosis of systemic lupus erythematosus

[0116] The subjects shown in Table 1 were used as test samples, including 71 patients with clinically confirmed systemic lupus erythematosus (also referred to as test samples) and 74 control group patients (including 29 healthy controls and 45 disease controls).

[0117] All samples were randomly divided into training set and validation set in a ratio of 7:3. The training set included 46 patients with SLE and 55 control patients (22 healthy patients and 33 disease controls), and the validation set included 25 patients with SLE and 19 control patients (7 healthy patients and 12 disease controls).

[0118] According to the above two methods, the relative expression values ​​of IFIH1 gene and CFLAR gene of each SLE patient and control group in the training set and validation set were substituted into the above joint diagnosis model formula to calculate the C value of each subject ( Figure 4 left image).

[0119] The C values ​​of each SLE patient and control group in the training set were plotted into ROC curves, and the critical value at the maximum Youden index was taken as the threshold value ( Figure 4 ), make diagnostic predictions for the training set and validation set samples respectively, and calculate their respective sensitivity, specificity, positive predictive value, and negative predictive value.

[0120] The results are shown in Table 5. It can be seen that the combined IFIH1 gene expression and CFLAR gene expression can be used to assist in the diagnosis of patients with systemic lupus erythematosus with high sensitivity and specificity.

[0121] Table 5 shows the sensitivity, specificity, positive predictive value and negative predictive value of the combined diagnostic C value

[0122]

Claims

1. Use of a substance for detecting the expression level of the IFIH1 gene and / or the CFLAR gene in the preparation of a product for auxiliary diagnosis or screening or auxiliary screening of systemic lupus erythematosus.

2. Use of a substance for detecting the expression of IFIH1 gene and CFLAR gene and a vector loaded with the following model formula in the preparation of a product for auxiliary diagnosis or screening or auxiliary screening of systemic lupus erythematosus; The model formula: C = 29.657*a+5.906*b-4.266, Where C is the combined index C value, a is the expression level of IFIH1 gene, and b is the expression level of CFLAR gene.

3. The use according to claim 1 or 2, characterized in that: The substance for detecting the expression level of the IFIH1 gene and / or the CFLAR gene is any one of the following: 1) comprising a primer pair for amplifying the IFIH1 gene and / or the CFLAR gene; 2) A PCR reagent or kit containing the primer pair.

4. A kit for auxiliary diagnosis of systemic lupus erythematosus, comprising the substance for detecting the expression levels of IFIH1 gene and CFLAR gene as claimed in any one of claims 1 to 3.

5. The kit according to claim 4, characterized in that: The kit also includes a carrier loaded with the following model formula; The model formula is C=29.657*a+5.906*b-4.266, wherein C is the combined index C value, a is the IFIH1 gene expression level, and b is the CFLAR gene expression level.

6. A device for assisting diagnosis of systemic lupus erythematosus, comprising a data acquisition module, a threshold acquisition module, a judgment module and an output module; The data acquisition module is used to obtain the expression level A of the IFIH1 gene or the CFLAR gene in the peripheral blood neutrophils of the subject; The threshold value acquisition module is used to take the critical value at the maximum value of the Youden index in the ROC curve of the expression amount of the IFIH1 gene or the CFLAR gene in the systemic lupus erythematosus group to the control group as the threshold value B; The judgment module is used to compare the expression amount A with the threshold value B to obtain a judgment result. The output module is used to output the judgment result obtained by the judgment module.

7. A device for assisting diagnosis of systemic lupus erythematosus, comprising a data acquisition module, a threshold acquisition module, a judgment module and an output module; The data acquisition module is used to obtain the expression levels of the IFIH1 gene and the CFLAR gene in the peripheral blood neutrophils of the subject, and then calculate the combined index C value through a model formula; the model formula is as follows: C=29.657*a+5.906*b-4.266, where C is the combined index C value, a is the expression level of the IFIH1 gene, and b is the expression level of the CFLAR gene; The threshold value acquisition module is used to draw a ROC curve of the combined index C value of the systemic lupus erythematosus group to the control group, and take the critical value at the maximum value of the Youden index as the threshold D; The judgment module is used to compare the combined index C value with the threshold D to obtain a judgment result. The output module is used to output the judgment result obtained by the judgment module.

8. A product for assisting diagnosis of systemic lupus erythematosus, comprising the substance for detecting the expression of IFIH1 gene and / or CFLAR gene according to any one of claims 1 to 3, the kit according to claim 4 or 5, or the device according to claim 6 or 7.

9. Use of the substance for detecting the expression level of IFIH1 gene and / or CFLAR gene according to any one of claims 1 to 3, the kit according to claim 4 or 5, or the device according to claim 6 or 7 in the preparation of a product for auxiliary diagnosis of systemic lupus erythematosus.

Images