Abstract: Objective: To investigate the clinical and laboratory characteristics of lupus nephritis(LN) patients by detecting the anti-nucleosome antibodies, anti-C1q antibodies and anti-double stranded antibodies(anti-ds DNA), and to clarify the risk factors of LN in the patients with systemic lupus erythematosus(SLE),and the significance of three kinds of antibodies in diagnosis of LN.Methods: A total of 120 SLE patients were selected and divided into LN group(n=60) and non-LN group(n=60).The ANAS data of 120 patients were retrospectively analyzed,the levels of anti-C1q antibodies were measured.The clinical symptoms and laboratory data of the patients with positive anti-dsDNA, -nucleosome and -C1q antibodies (3-pos group)and negative three kinds of antibodies(non 3-pos group) were analyzed in LN group.Results: The positive rate of anti-C1q antibody of the patients in LN group (40.00%) was higher than that in non-LN group (21.67%) (χ²=4.728, P=0.03).The positive rate of anti-dsDNA antibody in LN group was 66.67%, and it was 46.67% in non-LN group; the positive rates of the patients had significant difference between two groups (χ²=4.887, P=0.027). The positive rate of anti-nucleosome antibody in LN group was 58.33%, and it was 40.00% in non-LN group; the positive rates of the patients had significant difference between two groups (χ²=4.034, P=0.045).The positive rates of U1-snRNP, SmD1 and other antibodies Jo-1, SSA/Ro60kD, SSA/Ro52kD, SSB, ScL-70, CENP-B,and P0 had no significant differences between two groups(P>0.05). The levels of C3 and C4 and hemoglobinin of the patients in 3-pos group were higher than those innon 3-pos group (P<0.05);the age,the levels of immunoglobulin protein and C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR), white blood cell (WBC) and platelet had no statistically significant differences between 3-pos and non 3-pos groups(P>0.05).The clinical symptoms were not statistically significant in 3-pos and non 3-pos groups (P>0.05).Conclusion: The anti-nucleosome, anti-C1q and anti-dsDNA antibodies are the risk factors of SLE complicated with LN;the positive antibodies can improve the diagnostic rate of LN.The 3-pos patients have more severe damage in complements and blood system with higher renal disease activities.

Key words: anti-nucleosome antibody, lupus nephritis, anti-C1q antibody, anti-double stranded DNA antibody