Macrophage inflammatory protein-1: a prostaglandin-independent endogenous pyrogen.

Macrophage inflammatory protein-1 (MIP-1) produced a monophasic fever of rapid onset whose magnitude was equal to or greater than that of fevers produced with either recombinant human cachectin (or tumor necrosis factor) or recombinant human interleukin-1. However, in contrast to these two endogenous pyrogens, the fever induced by MIP-1 was not inhibited by the cyclooxygenase inhibitor ibuprofen. Thus, MIP-1 may participate in the febrile response that is not mediated through prostaglandin synthesis and clinically cannot be ablated by cyclooxygenase inhibitors.