Expression Of CD19⁺CD24^hiCD38^hiB Cells In Peripheral Blood Of Patients With Systemic Lupus Erythematosus

【Backgroud】 Systemic lupus erythematosus （SLE） is a chronic，multisystem-involved， typical autoimmune disease， the cause of which remainsunclear．The main pathogenesis is immune system disorders caused by T-lymphocyteabnormalities and B-lymphocyte over-activation．Regulatory B cells（Bregs） is a newsubset of B lymphocytes. Moreover, regulatory B cells that suppress immune responseshave been recognized as an important new component of the immune system. Furthermore,studies of murine disease models have demonstrated that regulatory B cells play asignificant role in autoimmune connective tissue diseases such as rheumatoid arthritis andsystemic lupus erythematosus. It is indicated in one recent study that humanCD19⁺CD24^hiCD38^hiB cells isolated from the peripheral blood of systemic lupuserythematosus（SLE） patients possess regulatory capacity.【Objective】： To access the expression and clinical significance ofCD19⁺CD24^hiCD38^hiB cells in patients with systemic lupus erythematosus.【Methods】: Thirty-six SLE patients，diagnosis complied with1997emendatoryACR classification standard,were recruited in the First Affiliated Hospital of SoochowUniversity from May2011to December2011, with their general and clinical materialscollected. According to systemic disease activity index （SLEDAI） integral evaluation,patients were divided into stable condition group（SLEDAI<10points）, disease activitygroup（SLEDAI≥10points）. Meanwhile,20healthy persons were selected as control group.CD19+CD24hiCD38hi, CD19+CD24intCD38intand CD19⁺CD24^hiCD38^-B cells subsets weredetected with Flow cytometery.The data was analyzed by SPSS18.0.【Results】（1）.Significantly higher percentages of CD19⁺CD24^hiCD38^hiB cells werediscovered in the PBMCs of patients with SLE compared to healthy individuals（P<0.05）. Significantly higher percentages of CD19⁺CD24^hiCD38^hiB cells were found in diseaseactivity group as compare to stable condition group （P<0.05）.（2）.Compared with healthy individuals，patients with SLE had significantly lowerpercentages of CD19⁺CD24^hiCD38^-B cells（P<0.05）.（3）.There is no statistical difference between percentages of CD19+CD24intCD38intBcells in the PB of controls versus patients with SLE （P>0.05）.（4）.The percentages ofCD19⁺CD24^hiCD38^hiB cells were positively correlated with SLEDAI （P<0.05）, but had nocorrelation with disease duration, age,C3, ESR, CRP, SLEDAI, etc （P>0.05）.（5）. The percentages of CD19⁺CD24^hiCD38^-B cells were negtively correlated withESR（P<0.05）;but had no correlation with disease duration, age, C3,ESR,CRP, SLEDAI,etc （P>0.05）.（6）.The expression of CD19+CD24intCD38intB cells had no correlation with diseaseduration, age,C3,ESR,CRP, SLEDAI, etc （P>0.05）.【Conclusions】（1） Compared with normal control group， CD19⁺CD24^hiCD38^hiB cells in the PB of patients with SLE increased significantly; In contrast, the percentages ofCD19⁺CD24^hiCD38^-B cells were significantly reduced in SLE patients. These resultssuggest that the inability of SLE CD19⁺CD24^hiCD38^hiB cells to suppress the expression ofproinflammatory cytokines by effector T cells is unlikely to be due to a numericaldeficiency, but be functionally impaired.（2） The percentages of CD19⁺CD24^hiCD38^hiB cells were positively correlated withSLEDAI; and compared with the stable condition patients，disease activity patients hadsignificantly higher percentages of CD19⁺CD24^hiCD38^hiB cells; these results suggest thatthe expression of CD19⁺CD24^hiCD38^hiB cells have correlation with disease activity.