| Objective To compare the difference of Hela cell nuclear extracts (Hela antigen) and Ehrlich ascite cell nuclear extracts (Ehrlich antigen) in detecting anti-RA33/36 antibody, and to present a simple and reliable method for detecting anti-RA33/36 antibody in rheumatoid arthritis(RA).Patients and Methods 281 consecutive cases of RA patients were included in the study group. The control group included: 41 cases of systemic lupus erythematosus (SLE), 12 osteoarthritis(OA), 10 Gout, 16 ankylosing spondylitis(AS), 10 mixed connective tissue disease (MCTD) and 50 healthy controls. All patients came from the clinic of Rheumatology of the First Affiliated Hospital of Shantou University Medical College during 1994-2001. Clinical data of RA patients was recorded, such as sex, age, onset age, disease duration, 28-joint-index,tender joint counts, swollen joint counts, limited joint counts, extra-articular manifestations, patient's and physician's global assessments of disease activity, patient's assessment of pain, 1991 revised classification of global functional status, the level of erythrocyte sedimentation rate(ESR), Oreactive protein, IgG, IgA, IgM, Y -globulin's, RBC and WBC, IgM rheumatoid factor(RF), antinuclear antibodies (ANA), anti-keratin antibodies(AKA), antiperinuclear factor(APF), Steinbrocker's classification and modified Sharp's radiological progression scores. Anti-RA33/36 antigen was extracted from Hela cells and Ehrlich ascite cells. Anti-RA33/36 antibody was detected at the sera titer of 1:10 using Western blotting. The data was analyzed by using the Statistical Package for the Social Sciences (SPSS) software package. The differences between the mean values were tested with t test. Chi-square test was used to compare percentages. Steinbrocker's classification and 1991 revised classification of global functional status were tested with Wilcoxon's rank test. All tests were 2-sided and 0=0.05 was considered significant.Results Detecting by using the Hela cell extracts as antigenic source on immunoblotting, the sensitivity of anti-RA33 antibody, anti-RA36 antibody and anti-RA33/36 antibody for RA was 14. 9% , 13. 5% and 6. 4% respectively, total 34. 8%, and the specificity was 92.1%, 96. 4% and 94. 9% respectively, total 83. 5%. When using the Ehrlich ascite cell nuclear extracts as antigen, the sensitivity of anti-RA33 antibody, anti-RA36 antibody and anti-RA33/36 antibody for RA was 23.5%, 15.3% and 5.3%respectively, total 44. 1%, and the specificity was 88. 5%, 94. 9% and 88.5% respectively, total 71.9%. The sensitivity and specificity of anti-RA33/36 antibody for RA was 52. 3% and 70. 5% by using two antigens. When detecting by using two antigen, the anti~RA33 antibody positive cases were 26 (9.3%), the anti-RA36 antibody positive cases were 18(6.4%), the anti-RA33^ 36 antibody positive cases were 6 (2.1%), the anti-RA33/36 antibody negative cases were 134(47.7%). There were 23 cases, of which anti-RA33/36 antibody was positive by using Hela antigen, and anti~RA33/36 antibody was negative by using Ehrlich antigen. There were also 49 cases, of which anti-RA33/36 antibody was positive by using Ehrlich antigen, and anti-RA33/36 antibody was negative by using Hela antigen. In addition, there were 25 cases, of which anti-RA33/36 antibody was positive, but their results were different between using Hela antigen and Ehrlich antigen. In summary, using Hela and Ehrlich antigen to detect anti-RA33/36 antibody, the proportion of the same result was 65. 5%, but 34. 5% was the different result. Detecting with two antigens, the same anti-RA33/36 antibody positive patients, their great part of indicators of disease activity and severity were higher than those of anti-RA33/36 antibody negative cases. The patients of positive anti-RA33/36 antibody detected by merely using Hela antigen or Ehrlich antigen, their great part of indicators of disease activity and severity were higher than those of anti-RA33/36 antibody negative cases, but lower than those of the same anti-RA33/36 antibody positive patient...
|
PDF Full Text Request