Objective: To investigate the correlation of anti-60 000 SSA antibody and anti-52 000 SSA antibody with systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS).
Methods: Western blotting against purified 60 000 SSA antigenic polypeptide and 52 000 SSA antigenic polypeptide were done to detect the anti-60 000 SSA and anti-52 000 SSA antibodies in 59 serum samples positive in anti-SSA antibodies, among which 44 samples were from SLE patients and 15 samples from SS patients.
Result: There was no significant difference in positive rate of anti-60 000 SSA antibodies between the SLE and pSS patients (P > 0.05). But the sole positive rate of anti-60 000 SSA antibodies of the SLA patients was 39.47% (15/38), significantly higher than that of the primary SS (pSS) patients ((6.67%, 1/15, P < 0.05). The positive rate of anti-52 000 SSA antibodies of the pSS patients was 93.33% (14/15), significantly higher than that of the SLE patients (23/38, 60.53%, P < 0.05). There was no significant differences in positive rates of anti-60 000 SSA antibodies and anti-52 000 SSA antibodies between the secondary SS (sSS) and pSS patients (P > 0.05).
Conclusion: The pSS patients mainly present anti-52 000 antibodies and with a very low sole anti-60 000 SSA antibody positive rate. Sole positivity of anti-52 000 SSA antibodies maybe correlated with pSS and is not a strong implication for the diagnosis of sSS. Sole positive anti-60000 SSA antibodies rate can be seen mainly in SLE.