Expression and significance of CD19+ CD5+ B cells and interleukin-10 in patients with systemic lupus erythematosus

Objective To access the expression and clinical significance of CD19+ CD5+ B cells and interleukin (IL)-10 in patients with systemic lupus erythematosus (SLE). Methods Forty-six SLE patients and ten healthy controls were recruited in the Second Affiliated Hospital of Shanxi Medical University. CD19+CD5+ B cells subsets were detected with flow cytometry. IL-10 level in serum were detected with enzyme linked immunosorbent assay (ELISA). The correlation between the expression of CD19+CD5+ B cells and serum level of IL-10 with ESR, systemic lupus erythematosus disease activity index (SLEDAI) score and complement was analyzed. Pair-wise comparison of means of groups was conducted with one-way ANOVA. Comparison between the two groups was conducted by LSD-t test. Correlations between variables were carried out using Spearman's rank correlation test. Results The percentage of CD19+CD5+ B cells in peripheral blood of SLE patients [(5.7± 2.1)%] was significantly lower than those in healthy control group [(19.1±2.9)%](t=2.431, P=0.005), and it had a negative correlation with SLEDAI score (r=-0.292, P=0.049). The IL-10 serum level of SLE patients [(18.8± 13.5) pg/ml] was significantly higher than the healthy control group [(8.3±2.9) pg/ml] (t=3.021, P=0.003), and it had a positive correlation with SLEDAI score (r=0.322, P=0.029). Conclusion CD19+CD5+ B cells and IL-10 may participate in the occurrence and development of SLE. The changes of CD19+CD5+ B cells and IL-10 in the peripheral blood might contribute to the pathogenesis and correlate with the disease activity of SLE. Key words: Lupus erythematosus, systemic; Interleukin-10; Antigens, differentiation, B-lymphocyte