OBJECTIVETo compare indirect immunofluorescence assay (IIFA) and enzyme-linked immunosorbent assay (ELISA) for detecting antinuclear antibodies (ANA) and anti-double-stranded DNA antibodies (anti-dsDNA).

METHODSA total of 125 serum samples were obtained from patients with established or suspected autoimmune disease, and 82 samples were used for ANA detection and 57 for anti-dsDNA detection using both IIFA and ELISA. Fourteen samples were examined for both ANA and anti-dsDNA. In cases where discrepancy occurred in the results by the two methods, extractable nuclear antigens were detected using immunoblotting.

RESULTSThe positivity rate of ANA detected by IIFA and ELISA was significantly different (87.8% and 73.17%, respectively, P<0.01), but the positivity rate of anti-dsDNA was similar between IIFA and ELISA (77.19% and 71.93%, respectively, P>0.05). The percent agreement between the two testing methods with different cutoff values of ANA and anti-dsDNA showed significant differences (P<0.01), and for some uncommon patterns, the percent agreement of the two methods was lowered in ANA detection but remained unchanged for anti-dsDNA with different ANA patterns. High percent agreements of the two methods were obtained with the cutoff ANA titer of 1:100 and the cutoff anti-dsDNA value of weak positivity, but they demonstrated a significant difference in testing low-titer ANA and anti-dsDNA.

CONCLUSIONIIFA is more sensitive than ELISA in detecting the total ANA and anti-dsDNA. ELISA prescreening combined with IIFA can obtain the information of the nuclear pattern and allow the observation of the titer alterations. The combination of two or more testing methods can greatly enhance the accuracy of the results.

Antibodies, Antinuclear ; analysis ; DNA ; immunology ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique, Indirect ; Humans

The efficacy of Saireito (a herbal preparation) against autoimmune recurrent abortion was evaluated clinically and immunologically. Saireito therapy was performed with 87 women having experienced 3 or more recurrent abortions in the early stages of pregnancy (less than 12 weeks gestation), and whose antinuclear antibody (ANA) and anti-cardiolipine antibody (ACA) test results were positive. The effects of this therapy on the percentage of women in whom abortion was successfully prevented (the abortion prevention rate), and on the antibody titer were investigated. Among the 49 women who became pregnant during the study period, the abortion prevention rate was 63.3%, the percentage of ANA positive cases was 65.6%(32/49), the percentage of ACA IgG and/or IgM positive cases (as evaluated by SRL methods) was 65.5%(29/49) and the percentage of both ANA and ACA IgG and /or IgM positive cases was 75.0%(12/49). Although the titer of ANA was not significantly reduced by this therapy, the titer of ACA IgM was reduced significantly.These results suggest that Saireito exerts its efficacy by suppressing humoral immunity through its adjustment of the Th1/Th 2 cytokine balance. This therapy is expected to be effective against ACA-positive recurrent abortion by reducing the effects of ACA. Furthermore, in 2 observed child birth cases whose ACA titer were not decreased by Saireito, different effective mechanisms were speculated; for example, suppression of platelet aggregation via saireito's component herbs (ninjin and bukuryou) similar to the effect seen with low-dose aspirin therapy, or its “risui” effect via its components (bukuryou, soujyutu, takusha and chorei).
Therapeutic procedure ; Unspecified Abortion ; Antinuclear Antibody Assay ; Antibodies ; Immunoglobulin M measurement

BACKGROUND: Anti-mitochondrial antibody (AMA) is a serological hallmark of primary biliary cirrhosis (PBC). AMAs are detected by an immunofluorescence assay (IF), which is subject to errors. We evaluated the diagnostic performances of the AMA ELISA test (the anti-MIT3 antibody) and PBC-associated antinuclear antibody (ANA) tests (the anti-gp210 and anti-sp100 antibodies). METHODS: AMA, anti-gp210, and anti-sp100 were measured in the sera of 130 subjects including patients for whom the AMA test was requested with the clinical suspicion of PBC, patients with other autoimmune diseases, and those undergoing health check-ups. AMA was detected by both IF and ELISA (anti-MIT3 antibodies), and anti-gp210 and anti-sp100 were detected by ELISA. The diagnostic performances of the anti-MIT3, anti-gp210, and anti-sp100 were compared with that of the AMA IF test. Associations between the presence of anti-sp100 or anti-gp210 and the diagnosis and biochemical abnormalities of PBC were investigated. RESULTS: The area under the curve of anti-MIT3 for the diagnosis of PBC was 0.934 (95% confidence interval, 0.877-0.970), and the agreement between anti-MIT3 and AMA IF was 93.8% (kappa, 0.82). The sensitivities of anti-MIT3 and AMA IF were both 100%, and the specificities were 83.1% and 81.4%, respectively, whereas the sensitivities of anti-gp210 and anti-sp100 were 41.7% and 16.7%, and their specificities were 94.9% and 97.5%, respectively. The presence of anti-gp210 was associated with the diagnosis of PBC (P=0.0001), but that of anti-sp100 was not. CONCLUSIONS: The diagnostic performance of anti-MIT3 is comparable to that of AMA IF. Anti-gp210 seems to be complementary to AMA for the diagnosis of PBC.
Antibodies* ; Antibodies, Antinuclear ; Autoimmune Diseases ; Diagnosis* ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique ; Humans ; Liver Cirrhosis, Biliary*

BACKGROUND: Infection can activate the immune system and may trigger the production of autoantibodies. It has been reported that malaria infection triggers the production of various autoantibodies. Therefore, we investigated the pattern and significance of antinuclear antibodies (ANA) found in patients with malaria infection. METHODS: Our study group included 36 patients who were diagnosed with malaria infection at Mokdong Hospital from July 1998 to July 2001. We performed antinuclear antibody test using indirect immunofluorescence method (Quantafluor, Sanofi Diagnostics Pasteur Inc., USA), extractable nuclear antigen test (ENA) using double immunodiffusion method (Nova Gel, Inova Diagnostics Inc., USA), anti-double stranded DNA Ab test (anti-ds DNA Ab) using Farr assay (DPC anti-DNA, Diagnostic products Corporation, USA), and anti-single stranded DNA Ab test (anti-ssDNA Ab) using enzyme immunoassay method (QUANTA, Lite ssDNA, Inova Diagnostics Inc., USA). RESULTS: Among the 36 patients, 32 patients (88.9%) showed ANA positivity and 27 patients (75.0%) showed cytoskeleton or speckled pattern of ANA. Anti-ssDNA Ab was found in 3 of 20 patients; however, anti-dsDNA Ab and ENA were not found in all patients. Patients who had ANA showed higher levels of IgG, IgM and IgA, compared with those patients who did not have ANA. Follow up (11-37 month) of the 13 patients with ANA positivity revealed no symptoms associated with autoimmune disorder. CONCLUSIONS: Malaria infection may develop ANA, especially cytoskeleton or speckled pattern. The follow up of patients with ANA positivity showed no symptoms associated with any autoimmune disorder, but further evaluation would be necessary to reveal the relationship between malaria infection and development of autoimmune disorder.
Antibodies, Antinuclear* ; Autoantibodies ; Cytoskeleton ; DNA ; Fluorescent Antibody Technique, Indirect ; Follow-Up Studies ; Humans ; Immune System ; Immunodiffusion ; Immunoenzyme Techniques ; Immunoglobulin A ; Immunoglobulin G ; Immunoglobulin M ; Malaria* ; Radioimmunoprecipitation Assay

BACKGROUND: Detection of antibodies to extractable nuclear antigens (ENAs) and dsDNA is needed for the diagnosis of and predicting prognosis in systemic autoimmune diseases. Recently introduced line immunoassay (LIA) has the advantage of detecting several autoantibodies simultaneously, and we evaluated its usefulness in the diagnosis of autoimmune diseases in comparison with enzyme-linked immunosorbent assay (ELISA). METHODS: Samples were collected from 437 patients referred by rheumatologists. FANA (fluorescent antinuclear antibody) test and LIA for the detection of 13 different autoantibodies, including 6 ENAs and dsDNA were performed. LIA-positive samples for ENA or dsDNA antibodies were further tested with ELISA. Final diagnosis was made by rheumatologists according to the diagnostic criteria. Agreement of results between LIA and ELISA was analyzed in 53 selected patients with systemic autoimmune diseases. RESULTS: The LIA detected antibodies to ENA and dsDNA in 118 and 22 patients, respectively, and ELISA detected 70.3% (83/118) and 45.5% (10/22) of LIA positive samples. Especially, 60.2% (71/118) of patients with positive ENA antibody on LIA was diagnosed as systemic autoimmune diseases. Patients having strong FANA titer and homogenous/speckled pattern showed higher prevalence of autoantibodies, but a small proportion of FANA negative patients also showed positive reactivity (LIA 10.8%, ELISA 5.2%). LIA showed a good agreement with ELISA for the anti-ENA antibodies (> or =80%), and a lower agreement for the anti-dsDNA antibody (67.9%). CONCLUSIONS: LIA detecting several autoantibodies simultaneously might replace ELISA for anti-ENA antibodies, but not for anti-dsDNA antibodies. When LIA is performed considering clinical manifestations and FANA, it could contribute to the diagnosis of systemic autoimmune disease.
Antibodies, Antinuclear/*analysis ; Antigens, Nuclear/immunology ; Autoimmune Diseases/*diagnosis ; DNA/*immunology ; Enzyme-Linked Immunosorbent Assay ; Female ; Fluorescent Antibody Technique, Indirect ; Humans ; *Immunoassay ; Male ; Middle Aged ; Reagent Kits, Diagnostic ; Reproducibility of Results

BACKGROUND: Anti-double stranded DNA antibody (anti-dsDNA) test is useful for the diagnosis and monitoring of systemic lupus erythematosus (SLE). Although several methods are available, none of them is completely satisfactory and differences among them have been reported. We evaluated the diagnostic performance of 6 commercial kits for anti-dsDNA detection. METHODS: A total of 142 sera (SLE [N=74], other systemic rheumatic diseases [N=50], other diseases [N=18]) were tested by 6 different assay kits using different antigenic sources of DNA: Crithidia luciliae immunofluorescence test (CLIFT), salmon testes (immunoblot, IB), human (ELISA I), salmon testes with nucleosome linker (ELISA II), plasmid (ELISA III), and synthetic oligonucleotides (chemiluminescence immunoassay, CLIA). RESULTS: With manufacturers' cut-off values, 6 test kits showed sensitivities of 55.4-91.9%. ELISA I had a greater sensitivity than the other five assays (P<0.001). The specificities of ELISA II, ELISA III, CLIA, and CLIFT were higher than those of ELISA I and IB (P<0.05). In ROC curve analysis, 3 ELISA kits and CLIA showed AUC values of 0.845-0.893, and revealed no significant differences among them (P>0.05). With cut-off values set at 95% of specificity, ELISA II had a higher sensitivity than ELISA III (63.5% vs. 41.9%, P<0.05). IB had poor concordance rates with other assays (42.0-65.0%). Pearson correlation coefficients among 4 quantitative assays were 0.667-0.798. CONCLUSIONS: Six different assays showed various performances depending on the methods and cut-off values used. Except IB, the other five assays can be used for the detection of anti-dsDNA.
Adult ; Antibodies, Antinuclear/*analysis ; Area Under Curve ; Chemiluminescent Measurements/*methods ; DNA/*immunology ; Enzyme-Linked Immunosorbent Assay/*methods ; Female ; Fluorescent Antibody Technique/*methods ; Humans ; Immunoblotting/*methods ; Lupus Erythematosus, Systemic/diagnosis ; Male ; Middle Aged ; ROC Curve ; Reagent Kits, Diagnostic ; Sensitivity and Specificity

BACKGROUNDHepatitis C virus (HCV) infection may induce autoimmune response and autoantibodies can be detected in chronic hepatitis C (CHC) patients. However, the reported positive rate of autoantibodies in CHC patients in China varies considerably. In this study, we investigated the prevalence of antinuclear antibodies (ANA) and anti-liver-kidney-microsome type 1 autoantibodies (anti-LKM-1) in a large cohort of CHC patients, and analyzed the factors related to the presence of the autoantibodies.

METHODSA total of 360 CHC patients were enrolled in this study. Serum ANA and anti-LKM-1 were detected by indirect immunofluorescence and enzyme-linked immunosorbent assay, respectively. Clinical analysis was performed to disclose the related factors to autoantibody production.

RESULTSThe prevalence of ANA and anti-LKM-1 in CHC patients was 12.5% (45/360) and 2.5% (9/360), respectively. Women had a higher prevalence than men (18.9% vs 11.4%, P = 0.046). Patients with positive autoantibodies had lower HCV RNA levels (1.2 x 10(7) copies/L vs 7.2 x 10(7) copies/L, P < 0.05). Positive ANA was associated with higher serum globulin (P < 0.05). Stratified analysis showed that there were no significant differences in age, HCV genotype, disease course, clinical stage, prevalence of cirrhosis and interferon therapy between autoantibody-positive and -negative subgroups.

CONCLUSIONAutoantibodies can be induced in the course of CHC, and some CHC patients can even develop autoimmune hepatitis.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antibodies, Antinuclear ; blood ; Autoantibodies ; blood ; Child ; Child, Preschool ; China ; Enzyme-Linked Immunosorbent Assay ; Female ; Fluorescent Antibody Technique, Indirect ; Hepatitis C, Chronic ; blood ; immunology ; Humans ; Male ; Middle Aged ; Prevalence ; Young Adult

OBJECTIVETo compare the diagnostic value of antibodies to mutated citrullinated vimentin (MCV) and some associated autoantibodies in juvenile idiopathic arthritis and to further analyze the relation between antibodies and inflammatory markers.

METHODAntibodies to cyclic citrullinated peptides (CCP) and anti-MCV antibodies were detected by enzyme-linked immunosorbent assay (ELISA), antiperinuclear factor (APF) and antikeratin antibody (AKA) by indirect immunofluorescent assay, as well as rheumatoid factor (RF) by latex agglutination test in serum samples from 113 patients with JIA and 56 children without rheumatoid arthritis.

RESULT(1) The positive rate of anti-MCV antibodies, anti-CCP antibodies, and RF was 16.8%, 14.2%, and 21.2% in the JIA. In the other group, the positive rate was 2.2%, 2.2%, and 6.5%. There was a significant difference between the two groups (χ(2)=8.105, 6.337, 7.036, P<0.05). The positive rate of AKA and APF were not significantly different. The area under the ROC curve of anti-MCV antibodies, anti-CCP antibodies, RF, AKA, APF was 0.579, 0.561, 0.578, 0.539, 0.505. (2) The positive rate of anti-MCV antibodies and anti-CCP antibodies were higher than other antibodies. In the RF-positive polyarticular disease patients, they were higher than those in the other subtypes (P<0.05). Antibody levels were not significantly different (P>0.05) from other subtypes. (3) The swollen joint counts and tender joint counts had a low correlation to anti-MCV antibodies, anti-CCP antibodies, RF, AKA and APF. No correlation was found between ESR, CRP and anti-MCV antibodies, anti-CCP antibodies, RF, AKA and APF.

CONCLUSIONThe diagnostic value of anti-MCV antibodies is low for JIA. The positive rate of anti-MCV antibodies was higher than the other antibodies in the classification of JIA. There was a low correlation between anti-MCV antibodies, anti-CCP antibodies, RF, AKA, APF and swollen joint counts, tender joint counts.

Antibodies, Antinuclear ; blood ; Arthritis, Juvenile ; blood ; Arthritis, Rheumatoid ; Autoantibodies ; blood ; Biomarkers ; blood ; Child ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique, Indirect ; Humans ; Peptides, Cyclic ; immunology ; ROC Curve ; Rheumatoid Factor ; blood ; Vimentin ; immunology