Division-linked differentiation can account for CD8( ) T-cell phenotype in vivo

Abstract

The CD8(+) T-cell response to infection involves a large initial expansion in the numbers of responding cells, accompanied by differentiation of these cells. Expression of the adhesion molecule CD62L is high on naïve cells and rapidly downregulated on the surface of the majority (approximately 90%) of cells during the 'effector' phase of acute infection. Adoptive transfer studies have been used to study differentiation in this system; however, relatively little work has investigated the phenotype of cells in the endogenous repertoire. We demonstrate that the extent of CD62L down-regulation is positively correlated with clone size in vivo, consistent with division-linked differentiation of re..