the cell cycle time of cd8+ t cells responding in vivo is controlled by the type of antigenic stimuluscd8 + t细胞的细胞周期时间反应体内受抗原刺激的类型.pdf

The Cell Cycle Time of CD8+ T Cells Responding In Vivo Is Controlled by the Type of Antigenic Stimulus 1 1,3 1,2,3 Heesik Yoon , Taeg S. Kim , Thomas J. Braciale * 1The Carter Immunology Center, University of Virginia, Charlottesville, Virginia, United States of America, 2 Department of Microbiology, University of Virginia, Charlottesville, Virginia, United States of America, 3 Department of Pathology, University of Virginia, Charlottesville, Virginia, United States of America Abstract ¨ A hallmark of cells comprising the mammalian adaptive immune system is the requirement for these rare naıve T (and B) lymphocytes directed to a specific microorganism to undergo proliferative expansion upon first encounter with this antigen. ¨ + In the case of naıve CD8 T cells the ability of these rare quiescent lymphocytes to rapidly activate and expand into effector T cells in numbers sufficient to control viral and certain bacterial infections can be essential for survival. In this report we ¨ + examined the activation, cell cycle time and initial proliferative response of naıve murine CD8 T cells responding in vivo to Influenza and Vaccinia virus infection or vaccination with viral antigens. Remarkably, we observed that CD8+ T cells could divide and proliferate with an initial cell division time of as short as 2 hours. The initial cell cycle time of responding CD8+ T cells is not fixed but is controlled by the antigenic stimulus provided by the APC