The Preliminary Study Of Regulatory B Cell In The Pathogenesis Of Childhood Asthma

Objective: To investigate the role of regulatory B cells in the pathogenesis in patients with asthma in children.Methods: 23 cases of patients with acute asthma had been included into reserach group,their mean age was 6.58±2.38 years,and the male to female ratio was 2.83:1.And 21 age-matcher healthy children as control group,their mean age was 5.43±1.91 years,and the male to female ratio was 2.00:1.(1)Flow cytometry was used to evaluate the proportions of Treg,Th1,Th2,Th17,Breg in peripheral blood and the expression levels of CD80,CD86 and CD1 d.(2)Transcription levels of IFN-γ,T-bet,GATA3,IL-17 A,IL-17 F,RORγt,IL-10 and TGF-β m RNA were detected by quantitative real-time PCR.(3)Plasma concentrations of IL-10 was detected by ELISA.Results:(1)The proportions of CD24 hi CD27~+ Breg in patients with acute asthma were significantly found to be lower than those of healthy controls(P<0.05);and its expression levels of CD80 and CD86 were down-regulated(P<0.05);the expression levels of CD1 d had downtrend,but there was no statisical significant(P>0.05).(2)The proportions of CD4~+CD25~+Foxp3~+ Treg in patients with acute asthma was significantly lower than that in healthy controls(P<0.05).(3)Plasma concentrations of IL-10 in patients with acute asthma was significantly lower compared to that in healthy controls(P<0.05).(4)The proportions of Th1 were decreased where as the proportions of Th2 and Th17 were increased in patients with acute asthma(P<0.05).(5)Expression levels of IL-10 in CD19~+ B cells had significant difference and its of TGF-β in CD19~+ B cells were increased in patients with acute asthma(P<0.05).(6)Expression levels of T-bet in CD4~+ T cells were down-regulated and its of IFNG,RORγt,IL-17 A and IL-17 F in CD4~+ T cells were up-regulated significantly in patients with acute asthma(P<0.05);there is no significant differences in expressions of GATA3(P>0.05).Conclusion: The decreasing of the proportion of CD24 hi CD27~+ Breg and the subdued function of IL-10 secretion may be important factors contributing to abnormal inducement of CD4~+T cells in patients with acute asthma;down-regulation of costimulatory molecules CD80 and CD86 may also affect the regulate function of CD24hiCD27~+ Breg.