Chemokines: attractive mediators of the immune response.

An effective inflammatory immune response first requires the recruitment of cells to the site of inflammation and then their appropriate activation and regulation. Chemokines are critical in this response since they are both chemotactic and immunoregulatory molecules. In this regard, the interaction between CCL5 and CCR5 may be critical in regulating T cell functions, by mediating their recruitment and polarization, activation, and differentiation. Various tyrosine phosphorylation signaling cascades can be engaged following chemokine receptor aggregation on T cells, including the Jak-Stat pathway, FAK activation, the MAP kinase pathway, PI3-kinase activation, and transactivation of the T cell receptor. This review will address specific aspects related to chemokine-T cell interactions and the molecular signaling mechanisms that influence T cell function in an inflammatory immune response.