Apoptosis Mechanism Of Mouse T-cell Lymphoma EL4 Cells Induced By Murine Cytomegalovirus

Objective To figure out whether the murine T-cell lymphoma cell line EL4 could be infected by murine cytomegalovirus(MCMV)and to observe the changes of cell morphological and apoptosis in EL4 cells after MCMV infection.To provide a new direction for the effective treatment of T-cell lymphoma.Methods EL4 cells were infected with MCMV smith strain with 1?10 and 100 multiplicity of infection(MOI)respectively.The cells were collected on the 1th?3th and 5th day after infection.The morphology of the cells was observed by light microscopy and Wright's-Giemsa staining.Cell viability was counted by trypan blue staining.RT-PCR-based assay was used to detect MCMV-DNA.Flow cytometry was used to detect apoptosis.RT-qPCR detected the mRNA expression levels of P53,P21,cFlip and Caspase8.The expression levels of Caspase8,P53,BAX,Bcl-2 and Cleaved-Caspase3 proteins were examined by Western Blot.Results EL4 cells infected with MCMV displayed with larger volume,irregular nuclei and the folded twist under light microscopic.Compared with the normal control group,the decreased cell viability and increased apoptosis rate of EL4 cells were observed in every infected group.Accordingly,the expression of apoptosis protein P53,Bax/Bcl-2,Cleaved-caspase3 and Caspase8 were up-regulated(P<0.05).And the survival rate,apoptosis rate and the level of apoptosis protein of MOI=10 infected EL4 cells were the most obvious at the 5th day.Compared with MCMV infection group(MOI=60),the copies of MCMV DNA in EL4 cells decreased in MCMV+GGV group[MOI=60,GCV 25(g/ml)],and cell apoptosis rate and apoptosis protein P53,Caspase8.Bax/bcl-2 expression decreased(P<0.05).Conclusion Murine T-cell lymphoma cell line EL4 cells could be infected by MCMV and displayed an increased apoptosis rate,by up-regulate the apoptosis protein P53.Bax-Bcl-2?Cleaved-caspase3 and Caspase8 after MCMV infection.Ganciclovir inhibit the killing effect of MCMV on EL4 cells by reduced the copies of MCMV DNA.