BACKGROUNDPatients with systemic lupus erythematosus often have various autoantibodies. The relationship between these antibodies is still poorly understood. The aim of the present study was to observe the anti-SSB antibody and anti-dsDNA antibody production profiles following immunization with synthetic SSB peptide alone, DNA alone or co-immunization with these two antigens.

METHODSSSB 214 - 225 aa peptide was synthesized by organic chemistry solid-phase peptide synthesis. Rabbits were immunized with the following antigens: synthetic SSB peptide linked with keyhole limpet hemocyanin (KLH), DNA, SSB plus dsDNA, KLH and PBS. Antibodies were measured by ELISA. Histopathology and direct immufluorescence assays were also applied.

RESULTSAnti-SSB and anti-dsDNA antibodies were produced following immunization with SSB peptide and DNA respectively. The level of SSB antibody in the co-immunization group was higher than that of the SSB peptide immunization group. The level of anti-dsDNA antibody in the co-immunization group was, however, lower than that in the DNA immunization group. Meanwhile, the level of anti-SSB antibody was higher than that of anti-DNA antibody in the co-immunization group. No morphological or immunological abnormalities were found in the heart, liver, kidney, spleen or skin tissues.

CONCLUSIONInhibition of anti-dsDNA-antibody was induced by co-immunization with synthesized SSB peptide and DNA, which might explain, at least partly, the mild disease in some LE subsets associated with SSB antibody.

Animals ; Antibodies, Antinuclear ; biosynthesis ; Autoantigens ; immunology ; DNA ; immunology ; Fluorescent Antibody Technique, Direct ; Immunization ; Rabbits ; Ribonucleoproteins ; immunology

BACKGROUNDSkin lesions are common manifestations in systemic lupus erythematosus (SLE). It is still unknown what the definite pathogenesis of skin involvement was and whether DNA participated in it. Our study was designed to explore the pathogenetic role and nature of nuclear antigen (DNA) deposited in the skin lesions of patients with SLE.

METHODSThirty skin samples from patients with SLE and 2 normal skin samples were studied. Extracellular DNA was evaluated by indirect immunofluorescence methods. The deposited immune complexes were extracted by cryoprecipitation, and DNA was then isolated with phenol and chloroform. DNA fragment sizes were detected by agarose gel electrophoresis. Finally, 8 different probes were used to analyze the origin of these DNA molecules using Dot hybridization.

RESULTSExtracellular DNA staining was found only in skin lesions, mainly those located in the basement membrane zone, vascular wall, and hair follicle wall. Normal skin and non-lesion SLE skin showed no fluorescence at locations outside the nuclei. There were no differences in the rate and intensity of extracellular DNA staining when comparing active phase to remission phase patients. No relationship was found between extracellular DNA and circulating anti-dsDNA antibodies. Deposited DNA fragments clustered into four bands of somewhat discrete sizes: 20 000 bp, 1300 bp, 800-900 bp, 100-200 bp. Small sized fragments (100-200 bp) were positively correlated with disease activity (P < 0.05, r = 0.407). Dot hybridization showed significant homology of the various extracellular DNA fragments examined with human genomic DNA, but not with DNA from the microorganisms and viruses we examined. There were also homologies between DNA samples from different individuals.

CONCLUSIONSDNA and its immune complexes may contribute to the pathogenesis of skin lesions in SLE. These DNA molecules range in size from 100 bp to 20 kb and may be endogenous in origin.

Antibodies, Antinuclear ; blood ; Antigen-Antibody Complex ; analysis ; DNA ; analysis ; immunology ; Humans ; Lupus Erythematosus, Systemic ; immunology ; Skin ; immunology ; Staining and Labeling

OBJECTIVETo investigate the prevalence of antinuclear antibodies (ANA) and anti-liver/ kidney microsomal type 1 antibodies (anti-LKM1) in patients with chronic hepatitis C (CHC)and to explore the mechanism of production of these autoantibodies.

METHODSSerum samples were collected from 360 patients with CHC (case group), 69 patients with chronic hepatitis B (CHB) and 69 patients with autoimmune hepatitis (AIH) (control group). Serum ANA and anti-LKM1 were detected by indirect immunofluorescence (HF) technique and enzyme-linked immunosorbent assay (ELISA), respectively. Multi-factor analysis was performed to explore the correlations of the production of autoantibodies with some factors such as age, sex, viral loads, HCV genotype, biochemical parameters and clinical characteristics.

RESULTSFifty-four (15%) of 360 patients infected with HCV were positive in autoantibodies. The prevalence of ANA and anti-LKM1 were 12.5% (45/360) and 2.5% (9/ 360), respectively. The positive rate of autoantibodies in patients with CHC was significantly higher than that in patients with CHB (15% vs 2.9%, P = 0.006), but significantly lower than that in patients with AIH (15% vs 47.9%, P < 0.001). Twenty-one (11.35%) of 185 male patients and 33 (18.86%) of 175 female patients were positive in autoantibodies, the difference in positive rate was significant (P < 0.05). HCV virus loads in the autoantibodies negative group were higher than that in the autoantibodies positive group (7.2 x 10(7) copies/L vs 1.23 x 10(7) copies/L, P < 0.05). There were not significant differences in age and genotype between the autoantibody positive group and the autoantibody negative group. The serum biochemical parameters of the autoantibody positive group were similar to those of the autoantibody negative group. The differences were not significant for the course of disease, clinical symptom, the incidence of cirrhosis between the autoantibody positive group and the autoantibody negative group. The prevalence of autoantibodies was not different for patients with or without interferon treatment (P > 0.05).

CONCLUSIONAutoantibodies related to AIH can be detected in CHC patients; interferon may not induce the production of autoantibodies; it is very likely that HCV infection induces the autoimmune reaction and the production of autoantibodies.

Adult ; Antibodies, Antinuclear ; blood ; immunology ; Autoantibodies ; blood ; immunology ; Female ; Hepatitis C, Chronic ; blood ; immunology ; virology ; Humans ; Male ; Middle Aged

Antibodies, Antinuclear ; blood ; Autoantibodies ; blood ; Autoimmunity ; Biomarkers ; blood ; Hepatitis C ; blood ; immunology ; Humans ; Mitochondria ; immunology ; Muscle, Smooth ; immunology ; Retrospective Studies

Adolescent ; Antibodies, Antinuclear ; blood ; Child ; Female ; Humans ; Sjogren's Syndrome ; diagnosis ; immunology ; therapy

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

OBJECTIVETo explore the follow-up visit, outcome and auxiliary diagnosis method on the cases with indeterminate antibody level measured by Western blotting as well as the related biological factors.

METHODSThe cases with indeterminate result were followed up according to the National Guideline for Detection of HIV/AIDS (2009) and samples were collected for HIV antibody detection, p24 antigen and nucleic acid were detected as a supplementary diagnosis at the same time. The samples were also be detected for HBV, HCV, TP, HTLV-I/II, ANA, and AFP, and the results were compared to that of screened positive and confirmed negative cases.

RESULTSA total of 73 were followed up successfully and taken a second HIV test, 25 cases were tested positive and 48 were tested negative for HIV during the follow-up period. For the 25 HIV positive cases, the HIV seroconversion rate was 100.00% at any time point when the interval between the first and returning detection was longer than 1 week. The major Western blotting bands for the cases with indeterminate result were p24 and gp160 and it was different between HIV positive and negative cases in Western blotting band profiles. The consistency and sensitivity of nucleic acid detection were higher than 90.00%, and were higher than that of p24 antigen (69.09% (38/55) and 27.27% (6/22)) (χ(2)(consistency) = 6.875, χ(2)(sensitivity) = 18.893, P < 0.05). The positive rates of ANA and AFP of indeterminate cases excluded from HIV infection were 20.83% (10/28) and 6.25% (3/48) and higher than that of screened positive and confirmed negative cases (0.00%), the difference had statistic significance (χ(2)(ANA) = 19.430, χ(2)(AFP) = 5.520, P < 0.05).

CONCLUSIONIt is critical to get timely diagnosis for the indeterminate cases according to the new national guideline for detection of HIV/AIDS. Nucleic acid detection has higher application value as auxiliary diagnosis for HIV infection than p24 antigen. The increased levels of ANA and AFP may be the factors resulting in the nonspecific indeterminate results.

Antibodies, Antinuclear ; blood ; Female ; Follow-Up Studies ; HIV Antibodies ; blood ; HIV Infections ; diagnosis ; immunology ; Humans ; Male ; alpha-Fetoproteins ; analysis

BACKGROUND/AIMS: Exclusion of liver disease from other causes such as autoimmune hepatitis is necessary for diagnosis of nonalcoholic fatty liver disease (NAFLD). However, there has been no study on the prevalence and significance of autoantibodies in the patients with clinically suspected NAFLD in Korea, where hepatitis B is endemic and autoimmune hepatitis is relatively uncommon. METHODS: We prospectively tested for anti-nuclear antibody (ANA), anti-smooth muscle antibody (ASMA), and anti-mitochondrial antibody (AMA) in 135 serially enrolled patients with suspected NAFLD. We compared the clinical characteristics and biochemical indices of the ANA-positive or ASMA-positive group with those of the autoantibody-negative group. RESULTS: Sixteen patients (11.8%) had serum autoantibodies; there was ANA in 8 patients (5.9%), ASMA in 7 (5.1%), and AMA in 2 (1.5%). Both ANA and AMA were positive in one patient. The ANA-positive or ASMA-positive group showed an older age (49.5+/-13.0 vs. 42.0+/-10.9 years, respectively, P=0.018) and higher levels of serum globulin (3.1+/-0.4 vs. 2.9+/-0.4 g/dL, respectively, P=0.037), compared with the autoantibody-negative group. Two cases with positive ANA or ASMA fulfilled the diagnostic criteria for probable autoimmune hepatitis and two cases with positive AMA were suspected as primary biliary cirrhosis. CONCLUSIONS: These findings suggest that autoantibodies could be found in some patients with suspected NAFLD in Korea, AMA-positivity or ASMA-positivity could be associated with old age and high serum globulin, and some of the autoantibody-positive cases could be diagnosed as autoimmune hepatitis or primary biliary cirrhosis. Further studies are necessary to clarify the clinical significance of autoantibody positivity in those patients.
Adult ; Aged ; Antibodies, Antinuclear/analysis ; Autoantibodies/*blood ; English Abstract ; Fatty Liver/*immunology ; Female ; Humans ; Male ; Middle Aged ; Muscle, Smooth/immunology

Systemic lupus erythematosus (SLE) is a typical autoimmune disease that's characterized by various autoantibodies to nuclear and cytoplasmic antigens. The presence of antinuclear antibodies (ANA) in serum is generally considered a decisive diagnostic sign of SLE. However, a small subset of SLE patients who had the typical clinical features of SLE was reported to show persistently negative ANA tests. Our report describes a 16-yr-old female who presented with the clinical manifestations of SLE such as malar rash, photosensitivity, arthritis, lymphopenia, pericarditis and proteinuria. The serum autoantibodies were all negative and renal biopsy showed that the histopathological changes of immune complex mediated the focal segmental necrotizing glomerulonephritis with crescent formation. She was treated with monthly pulse cyclophosphamide along with corticosteroids. During the 2-yr follow-up period, the proteinuria was markedly decreased and all of the ANA and anti-double stranded DNA antibody tests were negative. This case suggests that ANA may not be required in the pathogenesis of lupus nephritis.
Adolescent ; Antibodies, Antinuclear/*immunology ; Biopsy ; Female ; Follow-Up Studies ; Humans ; Lupus Nephritis/diagnosis/*immunology ; Tomography, X-Ray Computed

OBJECTIVETo explore the clinical and pathological features of primary biliary cirrhosis (PBC) patients with negative anti-mitochondria antibody (AMA).

METHODSTwo hundreds and eight PBC patients were enrolled. The clinical and histological data of the negative AMA cases were compared with the AMA/AMA-M2 positive cases.

RESULTS30 out of the 208 cases (14.4%) were AMA negative patients in our study. The general status, biochemical tests and histological findings between the two groups had no significant difference (P > 0.05). The Gamma-globulin, IgG, IgM and IgA levels of AMA/AMA-M2 positive PBC patients were higher than that of the AMA negative cases (P < 0.05). The abnormal rate of cholesterol in AMA negative PBC patients was 65.4% as compared to 50.4% in AMA/AMA-M2 positive cases, no significant difference existed between (P > 0.05). Anti-nuclear antibody (ANA) was observed in 29 (96.7%) AMA negative PBC patients, including 14 (48.3%) with granular pattern, 8 (27.6%) with nuclear membrane pattern, 6 (20.7%) with kinetochore pattern and 1 (3.4%) with homogeneous pattern. AMA negative PBC patients had elevated serum ALP, GGT, IgM and cholesterol levels, and decreased serum AST, IgG and IgA levels as compared with that of autoimmune hepatitis patients (P < 0.05, respectively).

CONCLUSIONIn cholestatic patients with elevated IgM and cholesterol levels, ANA positive with non-homogeneous pattern, the diagnosis of PBC should be suspected, albeit AMA negative. The clinical, biochemical and histological features of the AMA negative PBC patients were similar to classic PBC patients, but quite different from autoimmune hepatitis.

Adult ; Antibodies, Antinuclear ; analysis ; Female ; Humans ; Liver Cirrhosis, Biliary ; immunology ; pathology ; Male ; Middle Aged ; Mitochondria ; immunology ; gamma-Globulins ; metabolism