ABSTRACT
Objective To study B lymphocyte subsets(na(?)ve B cells,memory B cells and plas- mablasts)of peripheral blood in patients with rheumatoid arthritis(RA)and its relationship with autoantibod- ies and clinical manifestation.Methods Blood samples and clinical data of 60 patients with RA were enrolled into this study.They were divided into three groups:active,inactive and refractory RA based on clinical mani- festations and 24 healthy controls were included.CD19 and CD27 of B cells in peripheral blood of RA patients and healthy controls were detected using flow cytometry at single-cell level.Frequence of na(?)ve B cells (CD19~+CD27~-),memory B cells(CD19~+CD27~(dim)),plasmablasts(CD19~+CD27~(high))and average fluorescence in- tensity of CD19 were analyzed,and their relationship with clinical manifestations and rheumatoid factor(RF), anti-typeⅡcollagen(anti-CⅡ),anti-cyclic citrullianted peptide(CCP)antibodies were investigatied.Results Frequence of na(?)ve B cells and plasmablasts in peripheral blood of patients with RA was increased compared with normal control.In contrast,memory B cells in patients with RA were decreased.The na(?)ve B cells subset in inactive and refractory RA was higher than that of healthy controls(P<0.05),and the memory B cells subset in those groups was lower than that of healthy controls(P<0.05).The plasmablasts in active and refractory groups of RA were higher than those of healthy controls(P<0.05).The average fluorescence intensity of CD19 in peripheral blood in patients with RA was positively correlated with ESR,C-reactive protein(CRP),healthy assessment questionaire(HAQ),and plasmablasts was positively correlated with arthrocele index.Na(?)ve B cells,memory B cells and plasmablasts subsets had no relation with RF,anti-CⅡand anti-CCP antibodies. Conclusion B cell subsets in peripheral blood of patients with RA are significantly abnormal,characterized by expanded naive B cells and plasmablasts but diminished memory B cells.Plasmablasts are increasesd in active and refractory groups of RA,and have positive correlation with swollen joint index.B cells may play an important rote in the pathogenesis of RA.