tailieunhanh - Báo cáo y học: "Vaccination with live attenuated simian immunodeficiency virus causes dynamic changes in intestinal CD4+CCR5+ T cells"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: Vaccination with live attenuated simian immunodeficiency virus causes dynamic changes in intestinal CD4+CCR5+ T cells. | Li et al. Retrovirology 2011 8 8 http content 8 1 8 RETR0VIR0L0GY RESEARCH Open Access Vaccination with live attenuated simian immunodeficiency virus causes dynamic changes in intestinal CD4 CCR5 T cells 12 2 2 2 2 2 Bo Li Neil Berry Claire Ham Deborah Ferguson Deborah Smith Joanna Hall Mark Page 2 2 2 2 1 Ruby Quartey-Papafio William Elsley Mark Robinson Neil Almond Richard Stebbings Abstract Background Vaccination with live attenuated SIV can protect against detectable infection with wild-type virus. We have investigated whether target cell depletion contributes to the protection observed. Following vaccination with live attenuated SIV the frequency of intestinal CD4 CCR5 T cells an early target of wild-type SIV infection and destruction was determined at days 3 7 10 21 and 125 post inoculation. Results In naive controls modest frequencies of intestinal CD4 CCR5 T cells were predominantly found within the LPL TTrM-1 and IEL TTrM-2 subsets. At day 3 LPL and IEL CD4 CCR5 TEM cells were dramatically increased whilst less differentiated subsets were greatly reduced consistent with activation-induced maturation. CCR5 expression remained high at day 7 although there was a shift in subset balance from CD4 CCR5 TEM to less differentiated TTrM-2 cells. This increase in intestinal CD4 CCR5 T cells preceded the peak of SIV RNA plasma loads measured at day 10. Greater than depletion of intestinal CD4 CCR5 T cells followed at day 10 but overall CD4 T cell homeostasis was maintained by increased CD4 CCR5- T cells. At days 21 and 125 high numbers of intestinal CD4 CCR5- naive TN cells were detected concurrent with greatly increased CD4 CCR5 LPL TTrM-2 and IEL TEM cells at day 125 yet SIV RNA plasma loads remained low. Conclusions This increase in intestinal CD4 CCR5 T cells following vaccination with live attenuated SIV does not correlate with target cell depletion as a mechanism of protection. Instead increased intestinal CD4 CCR5 T cells may .