Leukotriene B sub(4) receptor BLT1 mediates early effector T cell recruitment

Leukotriene B sub(4) (LTB sub(4)) was originally described as a potent lipid myeloid cell chemoattractant, rapidly generated from innate immune cells, that activates leukocytes through the G protein-coupled receptor BLT1. We report here that BLT1 is expressed on effector CD4 super(+) T cells generated in vitro as well as in vivo when effector T cells migrate out of the lymphoid compartment and are recruited into peripheral tissues. BLT1 mediated LTB sub(4)-induced T helper type 1 (T sub(H)1) and T sub(H)2 cell chemotaxis and firm adhesion to endothelial cells under flow, as well as early CD4 super(+) and CD8 super(+) T cell recruitment into the airway in an asthma model. Our findings show that the LTB sub(4)-BLT1 pathway is involved in linking early immune system activation and early effector T cell recruitment.