Role of the Valence of Concanavalin A in the Activation of Guinea Pig Polymorphonuclear Leukocytes

Abstract

Stimulation of polymorphonuclear leukocytes (PMN) by tetravalent concanavalin A (α-ConA) induces membrane depolarization preceding the onset of superoxide anion (O₂^-) production. Both divalent and monovalent ConA analogues were studied to evaluate the role of valence. Monovalent ConA (m-ConA) was inactive in stimulating O₂^-production and divalent derivatives were less active than native a-ConA. Similarly, membrane depolarization was dependent on the valency of ConA. m-ConA did not induce a marked change in membrane potential, whereas sustained depolarization occurred with multivalent ConA. The formation of multiple linked interactions between surface receptors may be an important early event in the activation of PMN by ConA.