Inhibition of IL-8-induced W3/25+ (CD4+) T lymphocyte recruitment into subcutaneous tissues of rats by selective depletion of in vivo neutrophils with a monoclonal antibody

IL-8 recruits both neutrophils and lymphocytes in vitro and in vivo. To elucidate the mechanisms of lymphocyte recruitment in vivo by IL-8, we examined the role of neutrophil infiltration through selective depletion of circulating neutrophils using a mAb, RP-3. Selective depletion of neutrophils inhibited the IL-8 induced in vivo migration of the W3/25+ (CD4+) T cell subset but did not inhibit that of the MRC-OX8+ (CD8+) subset. These results suggest that CD4+ T cell migration into IL-8-injected s.c. tissues depends on the prior infiltration of neutrophils chemoattracted directly by IL-8.