Transendothelial chemotaxis of human α/β and γ/δ T lymphocytes to chemokines

Two subpopulations of human T lymphocytes expressing different antigen receptors, α/β and γ/δ, emigrate into inflamed tissues in distinctive patterns. We compared the transmigration of α/β and γ/δ T cells to C-C and C-X-C chemokines using an in vitro transendothelial chemotaxis assay. The C-C chemokines monocyte chemoattractant protein (MCP)-1, RANTES, macrophage inflammatory protein (MIP)-1α and MIP-1β stimulated similar, dose-dependent chemotaxis of purified γ/δ T cells, whereas MCP-1, RANTES, and MIP-1α produced greater chemotaxis of purified α/β T cells than MIP-1β. In contrast, the C-X-C chemokines interleukin (IL)-8 and interferon-γ inducible protein-10 (IP-10) did not promote chemotaxis of either α/β or γ/δ T cells. Three γ/δ T cell clones with differing CD4 and CD8 phenotypes also migrated exclusively to C-C chemokines. Phenotypic analysis of mononuclear cells that transmigrated from an input population of unfractionated peripheral blood mononuclear cells confirmed the results with purified γ/δ T cells. Our data demonstrate that human peripheral blood α/β and γ/δ T cells can transmigrate to MCP-1, RANTES, MIP-1α, and MIP-1β, and suggest that both T lymphocyte subpopulations share the capacity to emigrate in response to C-C chemokines during inflammation.