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).
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.
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).
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.