Tcell receptor expression

T cells are bone marro v-derived lymphocytes. There are six different types of Tcells identified in humans helper T cells (Th), cytotoxic T cells (Tc), memory T cells, regulatory T cells (Treg), natural killer T cells (NKT) and yb T cells. AD types have different roles in the adaptive immune systems and consequentiaUy distinct chemokine receptor expression patterns. 

Memory CD4 and CD8 T cells can be divided in effector and central memory Tcells. Effector memory cells are thought to home to nonlymphoid tissues, whereas the central memory T cells localize more to secondary lymphoid tissue [29]. Although originally distinguished by the expression of CCR7 by the central memory T cells, it is clear that both subsets express CCR7 [29, 34]. However, it is thought that these memory cells can express every appropriate chemokine receptor [29]. 

Campbell, J.J. et al. (2001) Expression of chemokine receptors by lung Tcells from normal and asthmatic subjects, /ouma of Immunology (Baltimore, Md 1950), 166, 2842-2848. 

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