Roles of phospholipase C beta2 in chemoattractant-elicited responses.

The physiological roles of phospholipase C (PLC) beta2 in hematopoiesis, leukocyte function, and host defense against infection were investigated using a mouse line that lacks PLC beta2. PLC beta2 deficiency did not affect hematopoiesis, but it blocked chemoattractant-induced Ca2+ release, superoxide production, and MAC-1 up-regulation in neutrophils. In view of these effects, it was surprising that the absence of PLC beta2 enhanced chemotaxis of different leukocyte populations and sensitized the in vivo response of the PLC beta2-deficient mice to bacteria, viruses, and immune complexes. These data raise questions about the roles that PLC beta2 may play in signal transduction induced by chemoattractants in leukocytes.