tailieunhanh - Báo cáo y học: " Tax gene expression and cell cycling but not cell death are selected during HTLV-1 infection in vivo"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Retrovirology cung cấp cho các bạn kiến thức về ngành y đề tài: Tax gene expression and cell cycling but not cell death are selected during HTLV-1 infection in vivo. | Zane et al. Retrovirology 2010 7 17 http content 7 1 17 RETR0VIR0L0GY RESEARCH Open Access Tax gene expression and cell cycling but not cell death are selected during HTLV-1 infection in vivo I I U . I 7 1 l h I I c I U . 1 2 7 I I f . z . I lz- - c- r- ir 1 h I iZz ĩU . zU Xz l ỉ3 h I ri I_I I z u-x l h I -f-x II I -X KI I X4 hz I f-i f V t t I k-x5 Linda zane David Sibon Lionel Jeannin Marc zandecKi iviarie-Hélène uelrau-Larue Antoine Gessain Olivier Gout6 Christiane Pinatel1 Agnès Langon1 FrancK Mortreux1 Eric Wattel1 2 Abstract Background Adult T cell leukemia results from the malignant transformation of a CD4 lymphoid clone carrying an integrated HTLV-1 provirus that has undergone several oncogenic events over a 30-60 year period of persistent clonal expansion. Both CD4 and CD8 lymphocytes are infected in vivo their expansion relies on CD4 cell cycling and on the prevention of CD8 cell death. Cloned infected CD4 but not CD8 T cells from patients without malignancy also add up nuclear and mitotic defects typical of genetic instability related to theexpression of the virus-encoded oncogene tax. HTLV-1 expression is cancer-prone in vitro but in vivo numerous selection forces act to maintain T cell homeostasis and are possibly involved in clonal selection. Results Here we demonstrate that the HTLV-1 associated CD4 preleuKemic phenotype and the specific patterns of CD4 and CD8 clonal expansion are in vivo selected processes. By comparing the effects of recent 1 month experimental infections performed in vitro and those observed in cloned T cells from patients infected for 6-26 years we found that in chronically HTLV-1 infected individuals HTLV-1 positive clones are selected for tax expression. In vivo infected CD4 cells are positively selected for cell cycling whereas infected CD8 cells and uninfected CD4 cells are negatively selected for the same processes. In contrast the Known HTLV-1-dependent prevention of CD8 T cell death pertains to both