Immunosuppression, interleukin-10 synthesis and apoptosis are induced in rats inoculated with Cryptococcus neoformans glucuronoxylomannan

CHIAPELLO LS, BARONETTI JL, AOKI MP, GEA S, RUBINSTEIN H, MASIH DT

Blackwell

Lugar: Londres; Año: 2004 vol. 113 p. 392 - 392

p class="MsoNormal" style="MARGIN: 0pt">Glucuronoxylomannan (GXM) is the major Cryptococcus neoformans capsular polysaccharide and represents the main virulence factor of this fungus. In in vitro studies we have demonstrated previously that this acidic and high-molecular-weight polysaccharide suppresses lymphoproliferation, modulates cytokine production and promotes apoptosis in spleen mononuclear (Spm) cells from rats. In this study we demonstrate that these phenomena also occur in vivo after the intracardiac inoculation of GXM into normal Wistar rats. The results of this study show suppression of the proliferative response Spm cells to concanavalin A (Con A) or heat-killed C. neoformans (HKCn) in the first 2 weeks after polysaccharide administration. In addition, increased levels of interleukin (IL)-10 were produced by Con A-stimulated Spm cells, coinciding with immunohistochemical GXM detection in the white pulp of spleen. In particular, high production of IL-10 with diminution of