Objective To evaluate the expression of autoantibodies to cell membrane associated with DNA (mDNA) in systemic lupus erythematosus (SLE).The specificity of these antibodies differs from antibodies to double stranded DNA.Method Using indirect immunofluorescence,serum samples were detected giving a characteristic pattern of peripheral membrane fluorescence on cultured HL60.Results This pattern was observed in 81 of 90 serum samplas of SLE patients,but absent in the serum samples of 35 rheumatoid arthritis,31 ankylosing spondylarthritis and 42 blood donors.In 20 Sjgren syndrome′s patients only one showed a positive test.Conclusion This novel rapid immunofluorescence method may serve as an identification test of SLE patients.Due to the sensitivity (90%) and specificity (98 8%),it is better than the other diagnostic tests such as the detection of antibodies to dsDNA and Sm.

Objective To compare the specificity and sensitivity of antibodies against cell membrane associated DNA (cmDNA)、 nucleosome (AnuA)、 double stranded DNA (dsDNA)、 deoxyribonucleoprotein (DNP) and antinuclear antibodies (ANA) in systemic lupus erythematosus (SLE). To analyze the relationship between these auto-antibodies in SLE. Methods One hundred and twenty five SLE patients and 118 other rheumatic diseases patients were studied. The latter included primary Sj?觟gren syndrome, ploymyositis, dermatomyositis, rheumatoid arthritis, osteoarthritis and systemic sclerosis. Indirect immunofluorescence was used to measure the anti-cmDNA antibodies and ANA. The enzyme-linked immunosorbent assay (ELISA) was used to measure the AnuA. Anti-DNP antibodies were detected by latex agglutination text and anti-dsDNA antibodies were detected by colloidal gold-technique. Results The seropositive rates of AnuA、 anti-cmDNA、 DNP、 dsDNA antibodies and ANA were 68%、 38.4%、 51.2%、 49.6% and 95.2% respectively in SLE patients. They were much higher than those of control groups (P

Objective To establish the method of anti-cell membrane associated DNA (mDNA) antibody detection, to evalute its sensitivity and specificity in systemic lupus erythematosus (SLE), and to analyze the relationship between anti-mDNA antibody and the clinical features of SLE. Methods Indirect immunofluorescence assay was used to measure anti-mDNA antibodies in sera of 207 SLE patients, 167 patients with other rheumatic diseases and 82 healthy controls. Using indirect immunofluorescence to detect the expression of mDNA with positive standard serum samples on nine cultured cell lines and pre-treated cells by DNAse, RNAse or trypsin. Results Of the serum samples, 73.3% SLE and 5.4% other rheumatic diseases were positive for anti-mDNA, but negative in 82 blood donors (P0.05). This study also proved that mDNA was expressed on B and T lymphocytes, the strongest staining was expressed on Raji cell line. The mDNA molecule was confirmed by pattern extinction on the cells pre-treated with DNAse but not RNAse or trypsin. Conclusion Anti-mDNA antibody is one of the most valuable marker in the diagnosis of SLE. Anti-mDNA antibody is valuable in diagnosis of SLE with negative anti-dsDNA, Sm, DNP, AHA and AnuA antibodies; but it has no significant with relationship the disease activity of SLE.

Objective To evaluate the quality of autoantibodies detection in China. Method Standardized samples were sent to 73 laboratories that are able to detect autoantibodies. The autoantibodies detected included antinuclear antibody (ANA), anti-dsDNA antibody, anti-extractable nuclear antigen (ENA) antibody, anti-mitochondrial antibody (AMA) and anti-smooth muscle antibody (ASMA). The analysis of testing results was double-blinded. Result The consistent rates of ANA, anti-dsDNA antibody, anti-ENA antibody, anti-mitochondrial antibody and anti-smooth muscle antibody were 86.2%, 75.4%, 62.7%, 100% and 61.1% respectively. Conclusion The overall accuracy has been elevated, but still needs to be improved.

Objective To consecutively investigate the quality of auto-antibody testing of the whole country and to improve quality.Methods A nation-wide investigation was carried out and hospitals or departments participating were notified by letter or telephone communication.Autoantibodies tested for quality control survey included anti-nuclear antibody (anti-ANA),anti-double-stranded DNA (anti-dsDNA)antibody,anti-extractable nuclear antigens (anti-ENA) antibody,anti-mitochondria antibody (AMA),anti-smooth muscle antibody (ASMA) and anti-citrulline antibody (anti-CCP).There were 15 samples in total for testing,including 3 control samples for each test.Same sample was used for both AMA and ASMA test.Sample distribution and data analysis were carried out double-blindly.A total of 114 hospitals or departments participated in the survey.Multiple testing methods were adopted including indirect immumo-fluo-rescence (IIF),immuno-blot (IB),dot-blot (DB),double immuno-diffusion (DID),enzyme linked immuno-sorbent assay (ELISA),chemiluminescent assay,dot-immunogold filtration assay.Results The accurate rates for this survey were 98％,96.6％,89.5％,98.1％,92.1％,96.4％ respectively for ANA,anti-dsDNA,anti-ENA,AMA,ASMA and anti-CCP.Anti-ENAs were further divided into anti-RNP,anti-Sm,anti-SSA,anti-SSB and anti-Scl-70 subgroups,and the accurate rates were 88.4％,96.8％,100％,100％ and 95.8％,respectively.Titers of ANA varied greatly among different labs,so did quantitative analysis of anti-CCP,AMA and antidsDNA by ELISA.However,the accuracy of ANA types determined by IIF was greatly improved.Detection rate of AMA and AMSAwas still low.Conclusion Among detected antibodies,ANA,anti-dsDNA and antiCCP are the most prominently improved.Accurate rate of anti-ENA antibody is slightly increased.

Objective To investigate the current national situation of autoantibody test in order to improve the quality of autoantibodies test.Methods Hospitals or departments in the whole country participated voluntarily or on invitation.Fifteen samples in total were distributed double-blindly,and autoantibodies including anti-nuclear antibody (ANA),anti-double-stranded DNA (anti-dsDNA) antibody,anti-extractable nuclear antigens (anti-ENA),anti-citrulline antibody (anti-CCP),anti-mitochondria antibody (AMA) and anti-smooth muscle antibody (ASMA) were tested in 6 samples.The samples were used for AMA and ASMA tests.Results A total of 148 hospitals or departments participated and multiple testing methods were adopted.The accurate rate of ANA(97.3％),AMA (96.1％),ASMA (92.1％) and anti-CCP (97.4％) were higher than that of anti-dsDNA (81.9％) and anti-ENA (77.2％).Anti-RNP and anti-Scl70 in anti-ENAs had the lower accurate rate,90.9％ and 80.3％ respectively.Taking data of the past 10 years together,the accuracy of antiSSA,anti-SSB,anti-Sm had been stable since 2009,while that of anti-RNP and anti-Scl70 decreased slightly.For methodology,indirect immunofluorescence was mainly adopted in the testing of ANA,anti-dsDNA,AMA and ASMA,immunoblotting was mainly adopted in anti-ENA detection and enzyme linked immunosorbent serologic assay was used for anti-CCP test.Conclusion No major variation of primary testing method is found in recent 10 years.Although diverged greatly among different methods,the accuracy of antibody detection has improved year by year.

Objective To investigate the susceptibility to rheumatoid arthritis (RA) with HLA- DR?1*04 subtypes.Methods One hundred and thirty-six RA patients and 79 patients with other rheumatic diseases were recruited in this study.HLA typing was performed using high-resolution PCR-SSP DNA techniques.The clinical features and serologic markers between different motifs were analyzed.Results Compared with other rheumatic diseases,the frequency of HLA-DR?1*04 alleles in RA patients was significantly increased(33.8% vs 12.7%)(OR=3.52,95%CI=1.43~5.43,P

Objective To study the disease spectrum,clinical and lab characteristic of cryoglobulinaemia.Methods The clinical and laboratory data of 58 patients with positive cryoglobulin admitted in Peking University People's Hospital from April 2010 to May 2014 were retrospectively analyzed.Results Among 58 patients,34 were diagnosed as autoimmune disease,8 as infectious disease,4 as hematological disease and 12 as primary cryoglobulinemia.Renal involvement was the most frequent clinical presentation among all cryoglobulin positive patients.Patients with autoimmune disease presented all clinical manifestations related to cryoglobulinaemia.Renal involvement (7/8) was prominent in patients with HBV/HCV infection,while other clinical presentations were rare.Among 4 patients with hematological disease,purpura was presented in 3 cases,renal involvement in 2,arthralgia in 2,fatigue,thrombosis or hyperviscosity was presented in 1 case,respectively;however,none of these patients had elevated rheumatoid factor (RF) level.Renal lesions were the most common reason for patients with primary cryoglobulinaemia to consult doctors,and 5 of them had positive antinuclear antibodies (ANA).Conclusions There is a broad spectrum of disease in cryoglobulinaemia.Multi-system involvement was most common in patients with autoimmune disease.For patients with HBV/HCV infection,extra-hepatic presentations were rare except renal involvement.Hyperviscosity syndrome tended to occur in patients with hematological disease.Since patients with primary cryoglobulinaemia had a relatively high rate of positive antinuclear antibodies,we should keep vigilance at the occurrence of autoimmune disease.

Objective To explore the diagnostic value of anti-cyclic citrullinated peptide (CCP) 3.1 IgG/IgA antibody detected by enzyme-linked immunosorbent assay (ELISA) in patients with rheumatoid arthritis (RA).Methods The ELISA was used to measure the anti-CCP3.1 antibody in the serum of 169 RA patients,100 patients with other rheumatic diseases (including systemic lupus erythematosus,Sjogren's syndrome and osteoarthritis) and 72 healthy controls.The diagnostic value of CCP3.1 was assessed and compared with the second generation of anti-CCP IgG (CCP2) antibody,the correlations between anti-CCP3.1 antibody and the clinical and laboratory parameters were analyzed.Two-independent samples t test,chi-square test and Spearman's correlation were adopted for statistical analysis.Results ① The average cut-off concentration of anti-CCP3.1 antibody was (1122±1429) U/ml in RA,(13±14) U/ml in other rheumatic diseases and (6±5) U/ml in healthy controls.② The area under curve of ROC for anti-CCP3.1 antibody and anti-CCP2 antibody were 0.923 and 0.936 respectively.There was no difference between the sensitivity (82％ vs 79％)and specificity (97％ vs 99％) of anti-CCP3.1 antibody and anti-CCP2 antibody.The Kappa values between anti-CCP3.1 antibody and anti-CCP2 antibody was 0.763.③ We also found that anti-CCP3.1 antibody was positive in 20％(7/35) of anti-CCP2 antibody negative,43％(18/42) of RF negative,62％(47/76) of AKA negative,71％(49/69) of APF negative and 13％ of autoantibodies negative patients,indicated that antiCCP3.1 antibody had a potential value in the diagnosis of serum negative patients with RA.④ The presence of anti-CCP3.1 antibody was correlated with RF,HRF-IgG,APF,AKA,GPI and IgA (P＜0.05),except disease activity.Conclusion The sensitivity of anti-CCP3.1 antibody is slightly higher than anti-CCP2 antibody.The Anti-CCP3.1 antibody is a very valuable parameter for the diagnosis of RA,especially in serum negative patients.

Objective　To investigate the impact of rheumatoid arthritis (RA)-associated HLA-DRβ1*0401,*0402,*0403 and*0404 subtypes on protein kinase A (PKA) signaling. Methods　To detect the activities of adenylate cyclase (AC), cAMP and PKA in transfectants expressing rheumatoid arthritis-associated HLA-DRβ1 subtypes and their mutants. Results　The levels of AC, cAMP and PKA of HLA-DRβ1*0401 and*0404 transfectants were significant lower than that of HLA-DRβ1*0402 and*0403 transfectants (P＜0.01). The mutant HLA-DRβ1*0403 tranfectants expressing DRRAE or QRRAA secreted lower levels of PKA, cAMP and AC (P＜0.01). Conclusion　RA-associated HLA-DRβ1*0401 and*0404 expression suppressed intracelluar PKA signaling pathway, and may mediate abnormal intracellular signaling in rheumatoid arthritis.