Influence Of Azithromycin On Peripheral Blood Dendritic Cells In Asthmatic Children

Objective To observe the influence of azithromycin in the expression of the co-stimulatory molecules CD80,CD86 and CD83 and the level of the interleukin-12 (IL-12) and interleukin-10(IL-10) on peripheral blood mononuclear cells(PBMC)direvd-dendritic cells (DCs) in asthmatic children, to investigate the immunomodulating effect of azithro-mycm.Methods 16 asthmatic children and 18 healthy children were selected. Periphe-ral blood mononuclear cells(PBMC) were isolated from venous blood by density gradient centrifugation in aseptic condition. Different concentration of azithromycin (blank control,0.1mg/L and 10mg/L) were added into the cultures in asthmatic group. The healthy control group was not interfered with azithromycin. Then PBMC samples were induced with rhGM-CSF,rhIL-4,rhTNF-a to make them transform into mature DCs. The expression of the co-stimulatory molecules CD80(B7-1),CD86(B7-2) and CD83 were examined by fluorescent activated cell sorter and the levels of IL-10 and IL-12 in the supernatant were determined by enzyme-linked immunosobent assay.Results①The expression of CD86 on DCs were significantly higher than that of healthy control group(t=2.27, P<0.05). There were no significant difference in the expression of CD80,CD83 between the two groups (t=1.17,1.34; P>0.05).②The level of IL-10 and IL-12 produced from DCs of asthmatic group were significantly lower than that of healthy control group (t'=3.31,3.39; P<0.01).③No significant difference in the expression of CD80,CD86 and CD83 on DCs among different concentration of azithromycin in asthmatic group(F=0.35～0.53, q=0.031～1.022, P>0.05).④The level of IL-10 produced from DCs of azithromycin 0.1mg/L and 10mg/L asthmatic group were significantly lower than that of blank control group(F=10.55, q=3.042,4.502; P<0.01); while there were no significant difference between azithromycin 0.1mg/L and 10mg/L (F=10.55, q=1.460, P>0.05). The level of IL-12 produced from DCs of azithromycin 0.1mg/L were significantly lower than that of blank control group and azithromycin 10mg/L group (F=8.09, q=3.148,3.940; P<0.01); while there were no significant difference between blank control group and azithromycin 10mg/L group(F=8.69, q=0.792, P>0.05).⑤IL-10 were postively correlated to IL-12 in asthma group(r=0.740, P<0.01), while there were no correlation in healthy control group(r=0.232, P>0.05).Conclusion①DCs dysfunction existed in asthmatic children. It mainly manifested in the increase of the expression of CD86 and the decrease of the secretion of IL-10 and IL-12, which indirectly led to the imbalance of the TH1/TH2.②There were no significant effect on the expression CD80, CD86 and CD83 on DCs after being interfered with azithromycin, while IL-10 and IL-12 decreased and had certain concentration dependence, suggesting that azithromycin had a negative role in immune regulation to DCs.