JP6628303B2 - Kit for diagnosing autoimmune disease and determination method for assisting diagnosis of autoimmune disease - Google Patents

Description

The present invention relates to a determination method aiding in the diagnosis of a diagnostic kit Contact and autoimmune diseases of the autoimmune disease.

  In autoimmune diseases, abnormalities in the immune system result in the appearance of self-reactive cells and autoantibodies. The diagnostic value of autoantibodies in autoimmune diseases is great, and vigorous research is being conducted on the detection of autoantibodies. Detection of autoantibodies, such as anti-double-stranded DNA antibodies in systemic lupus erythematosus and anti-cyclic citrullinated peptide antibodies in rheumatoid arthritis, has become an indispensable test in diagnosing autoimmune diseases or evaluating disease activity. (See Non-Patent Document 1).

  Non-Patent Document 2 discloses an antinuclear antibody test as a basic method for detecting autoantibodies. A frequently used method for detecting an antinuclear antibody (ANA) is an indirect fluorescent antibody method using HEp-2 cells as a substrate. In the indirect fluorescent antibody method, HEp-2 cells on a slide are exposed to patient serum, and a patient serum that has undergone an antigen-antibody reaction is detected with fluorescein isothiocyanate (FITC) -labeled anti-human immunoglobulin. Antinuclear antibodies are classified into uniform, marginal, mottled, nucleoli, cytoplasmic, PCNA, and centromere (scattered mottled types) according to their staining patterns. Antigens corresponding to each staining pattern are known, and detection of ANA has great significance in selecting a diagnosis or a subsequent test.

Takeuchi Ken, 2 others, "Systemic lupus erythematosus", Medical Examination, Japanese Association of Clinical Hygienists, 2002, 51 (9), 1256-1264 Miyo Kyoyo, "Progress in Antinuclear Antibody Research-Structure and Function of Nuclear and Cytoplasmic Proteins Recognized by Autoantibodies-", Rheumatism, 1992, 32 (4), 366-378.

  However, the antinuclear antibody test has a high positive rate even in healthy people. Further, there is a case where the judgment of the staining pattern lacks objectivity. For this reason, it is difficult to say that the accuracy of diagnosing an autoimmune disease by the antinuclear antibody test is sufficiently high. It is highly desirable that a test equivalent to an antinuclear antibody test can provide further useful information for diagnosis.

The present invention has been made in view of the above circumstances, diagnostic kits for autoimmune diseases which can improve the diagnostic accuracy of autoimmune diseases, more precisely determine the onset of and autoimmune diseases and to provide a determination method of assisting in the diagnosis of autoimmune diseases that can be.

The diagnostic kit for an autoimmune disease according to the first aspect of the present invention includes:
A first reagent for labeling a protein constituting a stress granule formed in a cell;
A second reagent for labeling a human antibody;
Is provided.

In this case, the first reagent is
A primary antibody that binds to the protein;
A secondary antibody labeled with a fluorescent dye, which binds to the primary antibody,
including,
It may be good.

Further, further comprising an inducer for inducing the formation of intracellular stress granules,
It may be good.

Further, the protein is
eIF3 eta,
It may be good.

A determination method for assisting diagnosis of an autoimmune disease according to the second aspect of the present invention,
An antibody to a protein constituting the stress granules formed in the cells, comprising a detection step of detecting from a sample collected from the subject,
Result of the detecting step, said subject is used to determine whether the autoimmune disease.

In this case, the autoimmune disease is
Rheumatoid arthritis,
It may be good.

ADVANTAGE OF THE INVENTION According to this invention, the diagnostic accuracy of an autoimmune disease can be improved. Further, according to the present invention, it is possible to determine the onset of autoimmune diseases more accurately.

It is a figure which shows the staining example of the anti-stress granule antibody positive case in an Example. (a) shows the fluorescence of Cy2, a marker of stress granules formed in the cytoplasm. b is a diagram showing the fluorescence of Cy3 which is a marker of a human antibody. c is a diagram in which a and b are superimposed. It is a figure which shows the staining example of the case where an anti-stress granule antibody positive and an anti-nuclear antibody positive in an Example. (a) shows the fluorescence of Cy2, a marker of stress granules formed in the cytoplasm. b is a diagram showing the fluorescence of Cy3 which is a marker of a human antibody. c is a diagram in which a and b are superimposed.

  An embodiment according to the present invention will be described. Note that the present invention is not limited by the following embodiments and drawings.

(Embodiment 1)
First, Embodiment 1 will be described. The kit for diagnosing an autoimmune disease according to the first embodiment includes a first reagent for labeling a protein constituting a stress granule formed in a cell, and a second reagent for labeling a human antibody.

  Stress granules (hereinafter, also simply referred to as “SG”) are aggregates of proteins and RNA formed in the cytoplasm in response to stress. Stress is a sudden change in environmental conditions, such as heat shock, oxidative stress, ischemia, viral infection, and the formation of denatured proteins and double-stranded RNA. The formation of stress granules is thought to be to temporarily preserve mRNA whose translation was stopped by stress and the mechanism of translation, and to start translation immediately after the release of stress. As the molecules constituting the stress granules, mRNA, ribosomal RNA excluding 60S, RNA binding protein and the like are known.

  The proteins constituting the stress granules are listed in, for example, Table 1. The first reagent is not particularly limited as long as it labels at least one of the proteins listed in Table 1. Preferably, the first reagent labels the eIF3 eta as a protein constituting a stress granule.

More specifically, the first reagent is, for example, a labeled antibody that binds to a protein constituting a stress granule. The labeled antibody preferably carries a radioisotope, an enzyme used in a color reaction, a fluorescent dye, and the like. The labeled antibody can label the protein by an immune reaction. When an antibody carrying a radioisotope is used, radiation from the radioisotope may be detected after the immunological reaction. In the case of using an antibody carrying an enzyme to be used in a color reaction, a chromogenic substrate for the enzyme is reacted after the immune reaction, and the protein can be detected by the generated color. In the case of using an antibody carrying a fluorescent dye, light having an excitation wavelength for the fluorescent dye may be applied after the immune reaction, and the fluorescence may be detected.

Examples of the radioisotope include deuterium ( ² H), tritium ( ³ H), ¹⁰ B, ¹¹ B, ¹³ C, ¹⁵ N, and ¹⁸ O. The enzyme used in the color reaction is a known enzyme such as alkaline phosphatase and peroxidase. Any known fluorescent dye can be used, and examples thereof include FITC, Cy2, Cy3, fluorescein, rhodamine, dansyl, and carbocyanine derivatives, and a green fluorescent protein as a fluorescent protein and a mutant thereof.

  Preferably, the first reagent includes a primary antibody that binds to the protein described above, and a secondary antibody that binds to the primary antibody and is labeled with a fluorescent dye. In this case, for example, a goat antibody against the above-described protein prepared in a non-human animal, for example, goat, may be used as the primary antibody, and a donkey anti-goat antibody labeled with a fluorescent dye may be used as the secondary antibody. The primary antibody and the secondary antibody can label at least one of the above proteins by the indirect fluorescent antibody method.

  The second reagent is not particularly limited as long as it labels a human antibody. The second reagent is, for example, a labeled human antibody, such as a human immunoglobulin antibody. The human immunoglobulin antibody is not particularly limited, and may be an anti-human IgG antibody, an anti-human IgM antibody, an anti-human IgA antibody, an anti-human IgD antibody, and an anti-human IgE antibody.

  Antibodies to the above proteins may be those produced by a known method, or commercially available antibodies. Antibodies prepared from any animal species such as donkey, goat, mouse, rabbit, rat, sheep, pig, bird, etc. can be used.

  The first reagent and the second reagent are not limited to antibodies, but may be labeled aptamers, compounds or peptides that bind to the above-mentioned proteins. The avidin-biotin system may be used for labeling the antibody.

  The cells are not particularly limited, and any cells can be used as long as stress granules are formed in the cells. For example, the cells may be primary cultured cells or various cell lines, and are preferably cancer cell lines, particularly U2OS which is an osteosarcoma cell line.

  Next, a method of using the diagnostic kit will be described. For example, when an antibody is used as the first reagent and the second reagent, the diagnostic kit is preferably used by a known immunostaining method. First, blocking treatment is performed on cells fixed with formaldehyde or the like and having stress granules formed in the cytoplasm. Next, the cells are exposed to the first reagent and the serum of the subject. Subsequently, after removing the unreacted first reagent by a washing treatment, the cells are exposed to the second reagent. After the washing treatment, the cells are fixed on a slide glass and observed with a fluorescence microscope.

  Labeling with the first reagent indicates the presence of stress granules. Labeling with the second reagent indicates the presence of a human antibody. Therefore, if the label of the first reagent and the label of the second reagent overlap with each other, the serum of the subject contains autoantibodies to the proteins constituting the stress granules formed in the cells. become.

  As shown in the Examples below, autoantibodies against proteins constituting stress granules are associated with autoimmune diseases. By using the present diagnostic kit, a patient with an autoimmune disease can be diagnosed. In particular, by using the present diagnostic kit for a subject who has a negative anti-nuclear antibody test and anti-cytoplasmic antibody test, the subject can be diagnosed with an autoimmune disease or easily diagnosed with an autoimmune disease. The morbidity can be determined.

  Here, the autoimmune diseases are various diseases caused by the immune system, and more specifically, autoimmune hepatitis, primary biliary cirrhosis, pemphigus vulgaris, pemphigus foliaceus, pemphigus Pemphigus, Passeow's disease, chronic thyroiditis, gastritis type A, ulcerative colitis, Crohn's disease, celiac sprue, insulin-dependent diabetes mellitus, Addison's disease, Goodpasture's syndrome, crescent-forming glomerulonephritis, multiple sclerosis, Guillain-Barre syndrome, myasthenia gravis, autoimmune hemolytic anemia, erythroblastosis, idiopathic thrombocytopenic purpura, dilated cardiomyopathy, chronic myocarditis, systemic lupus erythematosus and autoimmune infertility is there. In particular, autoimmune diseases include rheumatoid arthritis, Sjögren's syndrome, collagen disease, scleroderma, arthritis, Raynaud's disease, RS3PE (Remitting Seronegative Symmetrical Synovitis With Pitting Edema) syndrome, and osteoarthritis.

The diagnostic kit according to the present embodiment may further include an inducer for inducing the formation of intracellular stress granules. The inducing agent, sodium arsenite, diethyl maleate _{(DEM), H 2 O 2} , tunicamycin, thapsigargin, dithiothreitol, etoposide and thenoyltrifluoroacetone the like.

  As described above in detail, according to the diagnostic kit of the present embodiment, an autoimmune disease can be accurately diagnosed. Further, since the diagnostic kit includes the second reagent for labeling a human antibody, the presence or absence of an antinuclear antibody in a sample can be determined.

  Note that the first reagent may include a primary antibody and a secondary antibody. In the indirect fluorescent antibody method using a primary antibody and a secondary antibody, since a plurality of secondary antibodies react with the primary antibody, a signal of a label such as fluorescence intensity can be enhanced, and diagnosis is facilitated. In addition, if there is a primary antibody specific to the protein constituting the stress granules, a common secondary antibody can be used, so that the versatility of the secondary antibody is enhanced.

  Further, the diagnostic kit may include an inducer. The induction agent can induce the formation of stress granules in various cells such as passaged cells and cell lines, so that the convenience of the present diagnostic kit is further enhanced.

  When antibodies are used as the first reagent and the second reagent, proteins constituting the stress granules and human antibodies may be labeled by a fluorescent antibody complement method.

(Embodiment 2)
Next, a second embodiment will be described. As mentioned above, stress granules are formed in the cytoplasm in response to stress. Therefore, stress granules can be formed in cells by applying stress to the cells with an inducer or the like. On the other hand, in the cell according to Embodiment 2, the stress granules are formed in the cells without inducing the formation of the intracellular stress granules. The cells according to the present embodiment do not artificially induce the formation of stress granules, but contain, for example, salts such as Eagle's Minimal Essential Medium medium, non-essential amino acids, glutamine, and sodium bicarbonate as necessary. Even when cultured in a medium, stress granules are formed in cells.

  The cell according to the present embodiment can be prepared by introducing a gene encoding a protein that participates in the formation of stress granules or promotes the mechanism of forming stress granules into cells. The protein is, for example, a protein constituting a stress granule shown in Table 1. In this case, each gene encoding one or more proteins may be introduced into the cell.

  Genes can be introduced into cells by known biological, chemical or physical techniques. For example, a vector incorporating a gene encoding a protein constituting a stress granule may be introduced into cells by a known method such as a microinjection method, an electroporation method, a calcium phosphate method, and a lipofection method. Further, a gene encoding a protein constituting the stress granule may be introduced into cells using a transposon vector having a transposase gene.

  In introducing a gene, the genome of a cell is cut at an arbitrary site with a programmable endonuclease, and a gene encoding a protein constituting a stress granule is inserted into the genome using homologous recombination repair. Good. Examples of the programmable endonuclease include, but are not limited to, a transcription activator-like effector nuclease (TALEN), a zinc finger nuclease (ZFN), and a CRISPR-Regulated Pharmaceutical Inspection System (CRP). The programmable endonuclease is designed by a known method according to the nucleotide sequence near the cleavage site of the genome. Preferably, a gene encoding a protein constituting a stress granule may be inserted downstream of a gene having high transcriptional activity.

  The formation of stress granules in cells exposed to stress requires the phosphorylation of Ser51 of a regulatory subunit of the eukaryotic translation initiation factor 2 (eIF2α) complex. Therefore, cells according to the present embodiment can also be prepared by introducing factors such as a protein that promotes phosphorylation of Ser51 of eIF2α complex into cells.

  Preferably, at least one protein constituting the stress granules formed in the cells is labeled. As a protein label, for example, green fluorescent protein (GFP) is preferable. In the case of labeling with GFP, a protein constituting the stress granule may be expressed as a fusion protein with GFP.

  The fact that stress granules were formed in cells without artificial induction can be confirmed, for example, by the above-mentioned first reagent that labels a protein constituting the stress granules. When the cells are cultured and a protein constituting the stress granules, for example, eIFη is observed in the cytoplasm, it can be determined that the stress granules have been formed in the cells. In this case, as a positive control, the formation of stress granules can be easily confirmed by comparing with U2OS exposed to the inducer. The formation of stress granules can also be confirmed by quantifying the expression of a gene specific to the formation of stress granules.

  As described in detail above, according to the cells according to the present embodiment, since the stress granules are formed in the cells without using an inducer, human antibodies to the proteins constituting the stress granules are exposed. It is useful when detecting from the serum of the examiner. Since the step of causing the inducer to act on the cells is not required, the test time can be reduced, and the test can be performed easily. Since the human antibody is associated with an autoimmune disease, the cells according to the present embodiment are suitable for an autoimmune disease diagnostic kit.

  In the present embodiment, at least one type of protein constituting the stress granules formed in the cells may be labeled. This makes it possible to grasp the localization of the protein in the cell, so that the formation mechanism of stress granules can be easily observed or analyzed. Also, the presence or absence of a human antibody against the protein in the cell can be easily determined by comparing the position of the label of the human antibody that has acted on the cell with the localization of the protein in the cell.

  In another embodiment, a kit for diagnosing an autoimmune disease comprising the cell according to the present embodiment and a reagent for labeling a human antibody is provided. According to the diagnostic kit, a human antibody against a protein that forms a stress granule contained in a serum or the like of a subject can be detected without inducing the formation of a stress granule in cells. Disease can be diagnosed.

(Embodiment 3)
Next, a third embodiment will be described. The method for determining susceptibility to an autoimmune disease according to the present embodiment includes a detection step and a determination step.

  In the detection step, an antibody against a protein constituting the stress granule is detected from a sample collected from the subject. The protein is, for example, a protein shown in Table 1. Antibodies can be detected with human antibodies. The antibody can be detected as described above with a labeled human antibody, such as a human immunoglobulin antibody.

  The sample is blood, urine, synovial fluid, bile, gastric fluid, intestinal fluid, saliva, cerebrospinal fluid, etc. of the subject. Preferably, the sample is serum.

  In the determining step, the susceptibility of the subject to the autoimmune disease is determined based on the result of the detecting step. For example, when an antibody is detected from a sample, it is determined that the subject is more susceptible to an autoimmune disease than when no antibody is detected from the sample. On the other hand, when the antibody is not detected from the sample, it may be determined that the subject is less susceptible to the autoimmune disease than when the antibody is detected from the sample.

  The autoimmune disease is not particularly limited as long as it is a variety of diseases caused by the above-mentioned immune system, but is preferably rheumatoid arthritis, Sjogren's syndrome, collagen disease, scleroderma, arthritis, Raynaud's disease, RS3PE syndrome, and osteoarthritis. Disease.

  As described in detail above, the method for determining susceptibility to an autoimmune disease according to the present embodiment involves subjecting an antibody against a protein constituting stress granules, which is associated with the onset or susceptibility of an autoimmune disease, to a subject. Since the detection is performed from the sample derived from the examiner, the susceptibility of the subject to the autoimmune disease can be accurately determined.

  In addition, this determination method is particularly effective for determining the susceptibility of rheumatoid arthritis. The antinuclear antibody test has relatively many false positives and lacks objectivity in determining the staining pattern, so the clinical significance of this determination method in improving the accuracy of determining the susceptibility of rheumatoid arthritis is Extremely high. This determination method may be used alone in determining the susceptibility of rheumatoid arthritis, or may be used in combination with an antinuclear antibody test. In addition, the determination method may be used as a substitute for a test using a rheumatoid factor or an anti-cyclic citrullinated peptide antibody (ACPA), or may be used to assist a test using a rheumatoid factor or ACPA. Good.

  In another embodiment, a method for diagnosing an autoimmune disease is provided. The diagnosis method includes a detection step and a diagnosis step of diagnosing whether or not the subject has an autoimmune disease based on a result of the detection step. For example, in the diagnosis step, if an antibody against a protein constituting the stress granule is detected from a sample collected from the subject, the subject is diagnosed as having an autoimmune disease.

  In another embodiment, a method for predicting the prognosis of an autoimmune disease is provided. The prognosis prediction method includes a detection step and a prediction step of predicting a prognosis of an autoimmune disease of a subject based on a result of the detection step. For example, in the predicting step, the prognosis of the subject's autoimmune disease is higher when the antibody against the protein constituting the stress granules is detected from the sample collected from the subject than when the antibody is not detected from the sample. Predict bad.

  The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to the examples.

(Target cases)
The person who was not notified of the diagnosis randomly selected 90 cases subjected to an antinuclear antibody test among the cases visited at the Department of Rheumatology and Collagen Diseases at Hiroshima University Hospital, and made them the subjects of the following examination.

(Induction of stress granules and fixation of cells)
Cover slips were placed on 24-well tissue culture plates. Each well was seeded with 2.0 × 10 ⁵ osteosarcoma cell line U2OS. The seeded cells were cultured overnight in Dulbecco's modified Eagle's medium (DMEM) containing 10% fetal calf serum in the presence of 5% carbon dioxide at 37 ° C. The cells were adhered to the plate by culturing.

  To induce stress granules, 0.5 mM sodium arsenite was added to each well to a concentration of 100 μM, and the cells were cultured at 37 ° C. in the presence of 5% carbon dioxide for 40 minutes. After washing each well with Phosphate buffer saline (PBS), the cells were fixed with 4% formaldehyde diluted in PBS. Next, the cells were fixed with 100% methanol at −20 ° C. for 15 minutes, further immersed in 70% ethanol, and dehydrated at 4 ° C. for 4 hours or more. Thereafter, cells were soaked in PBS and stored at 4 ° C. until staining.

(Detection of anti-stress granule antibody)
The fixed cells after the induction of stress granules were blocked with PBS containing 5% normal horse serum. Subsequently, a goat anti-eIF3η antibody (manufactured by Santa Cruz) as a marker for stress granules and patient serum were mixed with a blocking solution so that the antibody was diluted to 1 μg / ml and the patient serum was diluted 40-fold. Was added. Next, the plate was incubated at 4 ° C. for 1 hour. After washing each well three times with PBS, a Cy2-labeled donkey anti-goat antibody, a Cy3-labelled donkey anti-human antibody, and Hoechst 33258 (1 ng / ml) for nuclear staining were diluted in PBS and added to each well. Plates were incubated for 1 hour at room temperature. After washing three times with PBS, the cells were fixed on a slide glass and observed with a fluorescence microscope (Olympus system biological microscope BX53).

(result)
Since a goat anti-eIF3η antibody bound to eIF3η binds to a donkey anti-goat antibody labeled with Cy2, SG aggregated in the cytoplasm can be detected by the fluorescence of Cy2. When the anti-SG antibody is present in the patient serum, the donkey anti-human antibody labeled with Cy3 binds to the anti-SG antibody bound to the stress granules. Therefore, the fluorescence of Cy3 is observed overlapping the position of the stress granules detected by Cy2. You.

  FIGS. 1 and 2 show examples of cases in which anti-SG antibodies were detected in patient sera, ie, cases of anti-SG antibody positive cases. The arrow in FIG. 1a indicates the fluorescence of Cy2, indicating the localization of SG formed in the cytoplasm. The arrow in FIG. 1b indicates the fluorescence of Cy3 and indicates the localization of the human antibody (IgG). FIG. 1c shows an image in which FIGS. 1a and 1b are superimposed. The position of the fluorescence of Cy2 indicating the localization of SG coincides with the position of the fluorescence of Cy3 indicating the localization of the human antibody. For this reason, it was shown that the patient's serum in this case contained an anti-SG antibody.

  FIG. 2 shows a staining example of a case positive for anti-SG antibody and positive for antinuclear antibody. As in FIG. 1, anti-SG antibody positivity can be confirmed from FIGS. 2a, 2b and 2c. Furthermore, since the fluorescence of Cy3 indicating the localization of the human antibody can be confirmed in the nucleus stained with Hoechst 33258 (FIG. 2b), it was shown that the serum of the patient in this case contained an antinuclear antibody. . In addition, the pattern of the antinuclear antibody was the same as the pattern detected by the FLUORO HEPANA TEST. From this, according to the present method, it is possible to detect anti-SG antibodies while maintaining the ability to detect antinuclear antibodies.

  When anti-SG antibody was detected by this method, 15 (17%) of 90 cases were anti-SG antibody positive cases. Table 2 shows the characteristics of the positive cases. 1 and 2 show the results of Case 13 and Case 14 in Table 1.

  Positive cases were diagnosed with 5 cases of undiagnosed arthritis, 4 cases of rheumatoid arthritis, RS3PE, Crohn's disease, systemic sclerosis, Raynaud's phenomenon, Sjogren's syndrome, and osteoarthritis, respectively. One case excluding Raynaud's phenomenon was a case complaining of joint pain.

  Of the 15 anti-SG antibody positive cases, only 2 were antinuclear antibody positive. The two cases positive for antinuclear antibodies were all mottled. Anti-cytoplasmic antibodies were negative in all cases. Among the 15 anti-SG antibody positive cases, 4 cases were rheumatoid factor (RF) positive (cases 1, 10, 13, and 14), and 2 cases were ACPA positive (cases 11 and 13). The normal range for rheumatoid factor is less than 15.0 IU / ml. The normal range for ACPA is less than 4.5 U / ml. "ND" in Table 2 means undecided.

  It is noteworthy that the anti-SG antibody was detected in 9 cases excluding rheumatoid factor-positive 4 cases and ACPA-positive 2 cases, although rheumatoid arthritis-related autoantibodies were negative. There were 4 cases that resulted in a definitive diagnosis of rheumatoid arthritis (cases 2, 11, 13, and 15), but only case 13 was clearly positive for both RF and ACPA, and the other three cases were RF And ACPA were both negative (cases 2 and 15), or only ACPA was positive with low titer (case 11).

  According to the results shown in this example, even if autoantibodies related to rheumatoid arthritis are negative, the possibility of developing cases of autoimmune diseases such as rheumatoid arthritis or autoimmune diseases by detecting anti-SG antibodies Can be found. Therefore, detection of an anti-SG antibody is helpful in diagnosing an autoimmune disease that could not be diagnosed, and is effective in determining susceptibility to an autoimmune disease.

  The embodiments described above are for explaining the present invention, and do not limit the scope of the present invention. That is, the scope of the present invention is shown not by the embodiments but by the claims. Various modifications made within the scope of the claims and the scope of the invention equivalent thereto are considered to be within the scope of the present invention.

  The present invention is suitable for diagnosis and treatment of autoimmune diseases.

Claims (6)

A first reagent for labeling a protein constituting a stress granule formed in a cell;
A second reagent for labeling a human antibody;
A diagnostic kit for an autoimmune disease, comprising: The first reagent comprises:
A primary antibody that binds to the protein;
A secondary antibody labeled with a fluorescent dye, which binds to the primary antibody,
The diagnostic kit for an autoimmune disease according to claim 1, comprising: Further comprising an inducer for inducing the formation of intracellular stress granules,
The kit for diagnosing an autoimmune disease according to claim 1 or 2. The protein is
eIF3 eta,
A kit for diagnosing an autoimmune disease according to any one of claims 1 to 3. An antibody to a protein constituting the stress granules formed in the cells, comprising a detection step of detecting from a sample collected from the subject,
Result of the detecting step, it said subject is used to determine whether suffering from an autoimmune disease,
Determination method aiding in the diagnosis of autoimmune diseases. The autoimmune disease is
Rheumatoid arthritis,
A determination method for assisting diagnosis of an autoimmune disease according to claim 5.