A study on the association of autoantibodies, chemokine, and its receptor with disease activity in systemic lupus erythematosus in North Indian population

Systemic lupus erythematosus (SLE) is a chronic and complex autoimmune disease characterized by the production of autoantibodies against a spectrum of nuclear antigens. RANTES and its receptor CCR5 have been associated with the pathogenesis of SLE. The objective of this study is to analyze autoantibodies (DNA/RNA), allelic distribution of RANTES and the association of levels of RANTES and its receptor CCR5 in SLE patients in North Indian region. The RANTES-403 and RANTES-28 polymorphism in the promoter region of RANTES gene was studied in 80 patients and 80 healthy controls. The levels of chemokine RANTES, its receptor CCR5, anti-dsDNA, and anti-SSA antibodies levels were determined. Disease activity was assessed with the systemic lupus erythematosus disease activity index (SLEDAI) score. All the parameters were studied for statistical analysis by using t test (graph pad prism) and correlation by SPSS data. PCR-RFLP performed showed 28C/C and the 403G/G genotypes in both patients and controls, but no other genotypes such as 28C/G, 28G/G and 403A/G, 403A/A were found. Patients had higher levels of RANTES (1840.48 ± 739.42 vs. 835.44 ± 70.48 pg/ml; P < 0.0001) and its receptor CCR5 expression (26.49 ± 0.16 vs. 24.72 ± 3.02 %; P < 0.05) compared to controls. The levels of autoantibodies anti-dsDNA and anti-SSA were also higher in patients than controls. The patients showing elevated anti-dsDNA had negative correlation with SLEDAI score (P < 0.05) while borderline patients were not found to be correlated. In case of anti-Ro/anti-SSA antibody levels, the borderline patients showed a moderately significant negative correlation as compared to controls than patients with elevated autoantibody (P < 0.01). The levels of RANTES and CCR5 were also higher in case of patients than controls. But there was no significant correlation of RANTES and CCR5 with disease activity. We were unable to find an association of RANTES polymorphism with SLE in North Indian population in our sample. No significant difference in allele distribution of RANTES-28 and RANTES-403 in the sample of 160 individuals was detected. Of the two autoantibodies studied, anti-Ro/anti-SSA levels in borderline lupus patients appeared as an important parameter for monitoring/diagnosis of lupus patients.