Interleukin 1α activity of peritoneal and bone marrow macrophages infected with Leishmania major and Leishmania donovani in vitro

In this study, the pattern of interleukin-1α (IL-1α) production by both peritoneal (PM) and bone marrow macrophages (BMM) from resistant (C3H/HeJ) and susceptible (BALB/c) mice was investigated, using a bioassay and an IL-1α-specific ELISA kit. PM from normal uninfected mice showed either an initial high (C3H/HeJ) or a neglected (BALB/c) level of IL-1α activity, respectively, probably due to thioglycollate stimulation. Infection with Leishmania major induced only a marginal effect on IL-1 production by both cells. Normal, uninfected and unstimulated BMM from both mice did not produce IL- 1α over a 7-day period of cultivation in vitro. Upon stimulation with either lipopolysaccharide (LPS) (BALB/c) or concanavalin A (Con A) (C3H/HeJ), both cell types produced IL-1α that peaked within the first 12-24 h following stimulation. BMM from C3H/HeJ and BALB/c mice failed to produce IL-1α when infected in vitro with L. major or L. donovani promastigotes. However, infection with these two parasites did not interfere with the capability of the host cell to produce IL-1α when stimulated with LPS or Con A. The level of IL-1α production was independent of the degree of parasitization of the macrophages. Similar results were observed with IL-1β and IL-6 production by BMM, even though their levels were generally slightly higher than those obtained with IL-1α. (C) 2000 Academic Press.