Abstract: Objective To analyze the correlation between expression levels of serum phosphatidylserine-specific phospholipase A1(PS-PLA1), chemokine ligand 19(CCL19), interleukin-17(IL-17), and interleukin-23(IL-23) and disease activity in patients with systemic lupus erythematosus(SLE). 
Methods Clinical data of 103 patients with SLE were collected retrospectively, and the patients were divided into the mild subgroups(n=31), the moderate subgroups(n=50), and the severe subgroup(n=22) according to the systemic lupus erythematosus disease activity score(SLEDAS). Another 62 people undergoing physical examination population during the same period were selected as the control group. The blood routine index ［white blood cell(WBC) count, lymphocyte percentage(LY%), platelet(PLT), hemoglobin(Hb)］ and immune function-related index ［immunoglobulin G(IgG), immunoglobulin A(IgA), immunoglobulin M(IgM), complement 3(C3), and complement 4(C4) ］ of the two groups were compared between two groups. The levels of serum PS-PLA1, CCL19, IL-17, and IL-23 between the research group and the control group as well as between each subgroup were analyzed, and the correlation of PS-PLA1, CCL19, IL-17, IL-23 and blood routine and immune function-related indexes was analyzed by Pearson correlation analysis method. 
Results The levels of complete blood WBC, LY%, PLT, Hb, C3, and C4 in the research group were lower than those of the control group, while the levels of serum IgG and IgA and IgM were higher than those of the control group(P＜0.05). The levels of serum PS-PLA1, CCL19, IL-17, and IL-23 in the research group were higher than those in the control group(P＜0.05). The levels of serum PS-PLA1, CCL19, IL-17, and IL-23 were higher in the severe subgroup than in the mild and moderate subgroups, and higher in moderate subgroup than in the mild subgroup(P＜0.05). The results of Pearson correlation analysis showed that PS-PLA1 and IgG expression were positively correlated(P＜0.05), CCL19, IL-17, IL-23 and IgG, IgA, IgM expressions were positively correlated(P＜0.05). and IL-17, IL-23 and C3 expression were negatively correlated(P＜0.05). 
Conclusion The levels of serum PS-PLA1, CCL19, IL-17 and IL-23 in patients with SLE are elevated, and their levels are closely related to the disease activity and cellular immune dysfunction, and may serve as new targets for the clinical diagnosis and treatment of SLE.

Key words: lupus erythematosus, systemic, interleukin-17, interleukin-23