Type II phospholipase A(2) is linked to cyclooxygenase-2-mediated delayed prostaglandin D-2 generation by cultured mouse mast cells following Fc epsilon RI- and cytokine-dependent activation

Treatment of murine bone marrow-derived mast cells (BMMC) with interleukin (IL)-10 and IL-1 beta increased the expression of type II secretory phospholipase A(2) (sPLA(2)), but not cytosolic PLA(2) (cPLA(2)), after culture for several hours. Further stimulation with IgE and antigen (IgE/Ag) increased cyclooxygenase (COX)-2 expression dramatically, accompanied by augmented delayed prostaglandin (PG) D-2 generation over several hours. BMMC were also found to express type IIC PLA(2) (PLA(2)-IIC), a recently described novel sPLA(2) possessing 16 cysteine residues, expression of which changed minimally after BMMC activation. Delayed PGD(2) generation was suppressed by similar to 80% by an antibody raised against recombinant murine type II sPLA(2). These results suggest that, of the three PLA(2)s expressed in BMMC, type II sPLA(2) is the critical enzyme that is coupled with COX-2-dependent PGD(2) generation elicited by IgE/Ag in the presence of IL-10 + IL-1 beta. (C) 1996 Academic Press