Influence of coal-arsenic exposure on human T cells proliferation and its mechanism / 中国地方病学杂志

ABSTRACT

Objective To explore the influence of coal-arsenic exposure on human T cells proliferation and its mechanism.Methods Blood samples colleoted from individuals which lived in arsenism area of coal-burning type and non-arsenism area in Guizhou Province were divided into exposed group(17),mild(35),moderate(38) and severe arsenism group(19)and control group(35)according to Diagnosis Smndard for Endemic Arsenism (WS/T 211-2001).T cell stimulation index wag determined by methyl thiazolyl tetrazolium(MTT)colorimetric method.The intracellular Ca2+ exponential(IECa2+)in peripheral blood mononuclear cell(PBMC)was analyzed by Fho-3/AM dye and flow cytometry.DNA binding activity of actively T cells nuclear factor(NF-AT)in PBMC was evaluated by electrophoretie mobility shift assay(EMSA).Results Concanavalin A(ConA)stimulation decreased the T cells stimulation indexes in exposed group,mild,moderate and severe arsenism groups(1.315±0.962, 1.611±1.224,1.114±0.545,1.289±0.875)compared with control group(2.322±1.241),all the differences being statistically significant(P＜0.01).After stimulated by anti-CD3 monoclonal antibody(McAb),the T cells stimulation index in exposed group,mild,moderate and severe arsenism group(0.997±0.177,1.103±0.291,1.007±0.221, 0.957±0.205) were lower than that of control group(1.842±0.429,P ＜ 0.01 ). IECa2+ of PBMC after treated by anti-CD3 McAb in mild,moderate and severe arsenism group( 110.130±49.637,92.429±31.191,77.640± 35.372) were lower compared with control group(145.986±59.450,P ＜0.01 ). Moreover,IECa2+ in moderat and severe arsenism group were lower than exposed group(121.337±46.410,P ＜ 0.05). DNA binding activity of PBMC NF-AT in mild,moderate and severe arsenism group(1.354±0.446,1.290±0.291,1.159±0.411 ) were lowered than that of control group(1.722±0.291,P ＜ 0.01) and exposed group(1.611±0.294,P ＜ 0.05). Conclusions The coal-arsenic exposure can reduce the human T cells stimulation indexes,IECa2+ in PBMC and the DNA binding activity of NF-AT. It suggest that arsenic may suppress the proliferation ability of human T cells,which may be partly related to the influence of arsenic on T cell receptor(TCR)/CD3 signal transduetion pathway.