Peripheral blood lymphocytes and monocytes heterogeneity in SLE patients treated by Belimumab

Abstract Objective: To estimate the effect of Belimumab on the heterogeneity of peripheral blood lymphocytes and monocytes subsets in systemic lupus erythematosus (SLE).Methods: There were three groups of populations, namely health controls (HC, n = 92), SLE patients treated (n = 26) and un-treated with BAFF (n = 155) in the present study. Cell subsets of CD3+T cells, CD3+CD4+T cells, CD3+CD8+T cells, CD19+B cells, CD16+CD56+NK cells, CD14+HLA-DR+monocytes, CD14+CD206+monocytes and CD14+CD163+monocytes were estimated by flow cytometry. Results: Compared with HC group, SLE patients had a higher level of CD3+T cells and CD3+CD8+T cells, but a lower level of CD3+CD4+T cells, CD16+CD56+NK cells, CD14+CD206+monocytes, and CD14+CD163+monocytes. Besides, the ratio of CD3+CD4+/CD3+CD8+T cells was much lower in SLE patients. Belimumab could effectively decrease CD19+B cells but increase CD3+T cell and CD3+CD8+T cells in the peripheral blood of SLE patients. Moreover, SLE patients had decreased CD14+CD206+ monocytes and CD14+CD163+ monocytes in peripheral blood, while Belimumab therapy did not affect the heterogeneity of monocytes in SLE.Conclusions: Our results revealed the heterogeneity of lymphocytes and monocytes in SLE patients. The clinical efficacy of Belimumab in SLE treatment is remarkable due to its significant effect on down-regulating B cell but up-regulating CD3+T cell and CD3+CD8+T cells in SLE.