Study On The Correlation Between 3 Serum Autoantibodies And Systemic Lupus Erythematosus

Objective To explore the relationship among the anti-α-actinin Abs, anti-calreticulin Abs, anti-dsDNA Abs and the pathogenesis of systemic lupus erythematosus (SLE), and to study the influence of 3 kinds of autoantibodies on the organ or system damage in SLE patients, providing scientific evidence for the diagnosis and treatment of SLE.Methods 36 new-onset SLE patients were selected from two hospitals, and 53 healthy volunteers were recruited as controls. General information, laboratory examination results and state of the organ or system damage were collected by self-designed questionnaire containing the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). The serum anti-α-actinin Abs and anti-calreticulin Abs were measured by competitive-ELISA, and the serum anti-dsDNA Abs were measured by indirect-ELISA. The data were analyzed by SPSS 13.0 software. Comparisons of the differences between different groups were made by the Student's t- test or Mann-whitney rank sum test for continuous variables,χ~2 test or Fisher's exact test for dichotomous variables. Pearson correlation or Spearman correlation were used to analyze the correlation between two continuous variables.α=0.05.Results The OD values of anti-α-actinin Abs and anti-calreticulin Abs in SLE patients were significantly lower than that in normal controls respectively, and the OD value of anti-dsDNA Abs was significantly higher than that in normal control. The positive rate of anti-α-actinin Abs, anti-calreticulin Abs and anti-dsDNA Abs in SLE patients were 19.4%, 47.2% and 50% respectively, which were significantly higher than that in normal control. In addition, there were no significant differences of clinical parameters between the Abs-positive patients and the negative patients. The positive rate of the term urine casts, elevated IgM and IgA in anti-α-actinin Abs-positive patients were higher than that in the negative patients. The positive rate ofγ-globulin in anti-calreticulin Abs-positive patients was higher than that in the negative patients. The positive rate of the term urine casts in anti-dsDNA Abs-positive patients was higher than that in the negative patients. Positive correlation had been found between the serum level of anti-α-actinin Abs, anti-dsDNA Abs and SLEDAI, and there was no correlation between the serum level of anti-calreticulin Abs and SLEDAI. The AUCROC of anti-dsDNA Abs was the highest, while 3 autoantibodies were effective for the diagnosis for SLE. Combination of anti-calreticulin Abs and anti-dsDNA Abs can significantly improve the sensitivity in the diagnosis of SLE.Conclusions anti-α-actinin Abs, anti-calreticulin Abs and anti-dsDNA Abs were rarely detected in the general group, they were effective for the diagnosis for SLE. Anti-α--actinin Abs and anti-dsDNA Abs may serve as useful markers of the disease activity of SLE. In addition, anti-α-actinin Abs may be used as a complementary parameter to differentiate LN from SLE without nephritis.