Abstract: Objective To investigate the polarization of Th1/Th2/Th3 cell function of dermatomyositis/polymyositis(DM/PM).Methods The culture supernatant levels of IL-4,IFN-γ,TGF-β1 that were produced by the peripheral blood mononuclear cells(PBMC)were detected by Sandwich ELISA in23DM/PM patients(DM18,PM5)and17healthy subjects.Results The level of IFN-γ(168.17±218.35ng/mL)produced by PBMC from the patients of DM/PM was significantly lower than that from normal controls(380.61±299.13ng/mL)(P<0.02).The levels of IL-4(34.68±11.12ng/mL)and TGF-β1(332.93±196.99ng/mL)were significantly increased,compared with those from normal controls(IL-4:27.95±7.55ng/mL,TGF-β1:231.64±83.92ng/mL)(P<0.05).The ratio of IFN-γto IL-4(5.05±6.25)was significantly smaller than that of normal controls(14.29±12.59)(P<0.02).Lung X-ray examination or CT was performed in 19DM/PM patients(DM16,PM3).Pulmonary fibrosis or a lot of increased lung marking on CT or pneumonograph was shown in eleven patients(DM10,PM1).The TGF-β1level in these patients was significantly higher than those(DM6,PM2) without pulmonary fibrosis or increased lung marking(P>0.05),and normal controls(231.64±83.92)(P<0.05).Conclusions There is imbalance of Th1/Th2/Th3 cytokines in of the patients with DM/PM:levels of IL-4and TGF-βare higher with lower IFN-γthan those in normal controls.

Key words: Dermatomyositis, Polymyositis, Interleukin-4, Interferon typeⅡ, Transforming growth factor beta