Influence of different doses of vitamin A supplements on the function of T help 17 and regulatory T cells in peripheral blood of asthmatic children / 中华实用儿科临床杂志

ABSTRACT

Objective To observe the effect of vitamin A(VitA) on T help 17(Th17) and regulatory T cells (Treg) in the peripheral blood in children with asthma and their dose effect relationship,and to investigate the immunoregulation mechanism of VitA.Methods Twenty children with asthma (asthma group) and 16 healthy children (healthy control group) were selected.Peripheral blood mononuclear cells(PBMC) were isolated from venous blood by density gradient centrifugation in the aseptic condition.Different concentrations of VitA [0.0μmol/L (blank control),0.5μmol/L,1.0μmol/L,2.0μmol/L] were added into the cultures in the asthma group.The healthy control group were not interfered with VitA.The supernatant was collected after 72 h.The levels of interleukin 17 (IL-17),interleukin 10(IL-10) and transforming growth factor-β1 (TGF-β1) in the supernatant were determined by enzyme-linked immunosorbent assay.Results (1) IL-17 levels produced by PBMC in the asthma group were significantly higher than those in the healthy control group [(960.53±75.59) ng/L vs (425.07±70.71) ng/L,P＜0.01],and the levels of IL-10 and TGF-β1 were significantly lower than those in the healthy control group [(53.13±6.94)ng/L vs (84.41±6.02) ng/L,(304.51±51.52) ng/L vs (489.45±73.68) ng/L,all P＜0.01].(2) IL-17 levels produced by PBMC in the 0.5μmol/L,1.0μmol/L and 2.0μmol/L VitA concentration of the asthma group [(588.95±44.18)ng/L,(573.13±27.43) ng/L,(686.71±38.98) ng/L] were significantly lower than those in the blank control group[(960.53±75.59) ng/L,all P＜0.01],and IL-17 levels in the 2.0 μmol/L VitA concentration were significantly higher than those in 0.5μmol/L and 1.0μmol/L concentration groop (P＜0.01).(3) IL-10 levels produced by PBMC in the 0.5μmol/L,1.0μmol/L and 2.0μmol/L VitA concentration of the asthma group [(105.35±10.79) ng/L,(111.21±16.11) ng/L,(81.09±6.05) ng/L] were significantly higher than those in the blank control group[(53.13±6.94) ng/L,all P＜0.01],TGF-β1 levels produced by PBMC in the 0.5μmol/L,1.0μmol/L and 2.0μmol/L VitA concentration of the asthma group[(933.01±73.98) ng/L,(1223.31±105.99)ng/L,(776.98±145.44) ng/L] were significantly higher than that in blank control group[(304.51±51.52) ng/L,all P＜0.01],and the levels of IL-10 and TGF-β1 in the 0.5 μmol/L and 1.0μmol/L concentration group were significantly higher than those in the 2.0μmol/L concentration group(all P＜0.01).The level of TGF-β1 in the 1.0μmol/L concentration group were significantly higher than that in the 0.5μmol/L concentration group (P＜0.01).Conclusions The function of Th17 in children with asthma during asthma attack was enhanced,and the function of Treg cells was reduced.The balance disorder of the functions of Th17 and Treg cells occurred.VitA can reduce the function of Th17 in peripheral blood,and enhance the activity of Treg cells in the children with asthma.The physiological level of VitA has the best effect,if high VitA concentration is high its effect is significantly decreased.