Nitric oxide and IL-10 production induced by PIII - A fraction of Schistosoma mansoni adult worm antigenic preparation - Associated with downregulation of in vitro granuloma formation

Identification and characterization of Schistosoma mansoni antigens that ca n provide protective immunity, as well as an investigation of their role in host-parasite interaction, is crucial For understanding the complex immuno regulatory events that modulate granuloma formation in schistosomiasis. Pre vious work by our laboratory identified a fraction of S, mansoni soluble ad ult worm antigenic preparation (SWAP), named PIII, obtained by anionic chro matography on fast protein liquid chromatography (FPLC), This fraction was able to elicit significant in vitro cell proliferation and at the same time lower in vitro and in vivo granuloma formation when compared either to SWA P or to soluble egg antigens (SEA), In the present work, we investigate som e biological activities of PIII, such as the stimulation of nitric oxide (N O) and cytokine production. Our data demonstrated that SEA, SWAP and specia lly PIII were able to induce a time-dependent increased NO production durin g in vitro granuloma reaction. Besides that, PIII evoked increased IL-10 pr oduction, but not IL-2 or IFN gamma. Collectively, our results indicate the possibility that the modulation role of PIII on in vitro granuloma might b e mediated in part by its ability to induce the higher production, initiall y of IL-10, and lately of NO. Human Immunology 60, 305-311 (1999). (C) Amer ican Society for Histocompatibility and Immunogenetics, 1999. Published by Elsevier Science Inc.