ATP-binding cassette protein E (ABCE1) has been annotated as an Rnase L inhibitor in eukaryotes. Previous study showed that the overexpression of ABCE1 was related with the occurrence and clinical stage of lung adenocarcinoma. As an initial investigation into the novel functions of ABCE1, siRNA-expressing vectors targeting sites of the ABCE1 gene were constructed from RNAi-Ready pSIREN-DNR-DsRed-Express vector. Cultured 95-D and NCI-H446 lung carcinoma cells were transfected with the siRNA-expressing vectors using FuGENE 6 and transfection efficiency was determined by using fluorescence microscopy. The expression level of ABCE1 protein was determined by Western blot and immunofluorescence staining. Cell viability was determined by MTT, cell cycle was analysed by flow cytometry.The apoptotic rate was observed by ELISA. Fluorescence microscopy showed a satisfactory transfection efficiency which was about 42.70%. Cell viability and the growth fraction were markedly suppressed, whereas the apoptosis was significantly increased in SiRNA-95-D and SiRNA-NCI-H446 cells than controls(P< 0.05). It can be concluded that the siRNA targeting ABCE1 gene shows a dramatic inhibitory effect on RNA transcription and protein expression and a promoting effect on the apoptosis in 95-D/NCI-H446 cells, which offers a reliable base for the further in vivo experiment.

Graft versus host disease(GVHD)is a refractory complication of allogeneic hematopoietic stem cell transplantation for the treatment of malignant and non-malignant hematopoietic diseases.Inflammatory cascade responses and cellular immune reactions are the major factors underlying GVHD pathogenesis.Cells producing the cytokine,interleukin(IL)-21 are crucial players involved in injured tissues in GVHD patients.Besides T helper 17 cells,follicular T helper(Tfh)cells are a new source of IL-21 and play a vital role in GVHD pathogenesis.Tfh cell function is mostly regulated by T-follicular regulatory(Tfr)cells that are also located in the germinal center.This review highlights recent advances in the role of Tfh and Tfr cell function in GVHD pathogenesis.New insights are provided into the potential for clinical application in GVHD prevention and treatment.