In vitro and in vivo chemotaxis of guinea pig leukocytes toward leukotriene B4 and its w-oxidation products

Leukotriene B₄ (LTB₄), 20-OH-LTB₄, and 20-COOH-LTB₄ were studied for their relative activities towards guinea pig peritoneal eosinophils and neutrophils during in vitro chemotaxis in modified Boyden chambers. The leukotrienes were also injected into guinea pig skin, and the cellular infiltrate in 4 hour biopsies was evaluated histologically. Eosinophils migrated more actively than neutrophils towards LTB₄in vitro, while in vivo, more neutrophils were observed. 20-OH-LTB₄, was markedly less active than LTB₄in vivo and in vitro, and 20-COOH-LTB₄ was barely active at all. Crude ionophore-stimulated neutrophil supernatants (ECF) were more active towards eosinophils than towards neutrophils, both in vivo and in vitro, compared to the pure leukotrienes. The data confirm the potent chemotactic properties of LTB₄ for eosinophils and neutrophils, with less activity of its w-metabolites.