Eosinophils elicit proliferation of naive and fungal-specific cells in vivo so enhancing a T helper type 1 cytokine profile in favour of a protective immune response against Cryptococcus neoformans infection.

GARRO AP; CHIAPELLO L S; BARONETTI JL; MASIH DT

IMMUNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2011 vol. 134 p. 198 - 198

0019-2805

xperimental Cryptococcus neoformans infection in rats has been shown to have similarities with human cryptococcosis, revealing a strong granulomatous response and a low susceptibility to dissemination. Moreover, it has been shown that eosinophils are components of the inflammatory response to C. neoformans infections. In this in vitro study, we demonstrated that rat peritoneal eosinophils phagocytose opsonized live yeasts of C. neoformans,and that the phenomenon involves the engagement of FccRII and CD18.Moreover, our results showed that the phagocytosis of opsonized C. neoformans triggers eosinophil activation, as indicated by (i) the up-regulation of major histocompatibility complex (MHC) class I, MHC class II and costimulatory molecules, and (ii) an increase in interleukin (IL)-12, tumour necrosis factor-a (TNF-a) and interferon-c (IFN-c) production. However, nitric oxide (NO) and hydrogen peroxide (H2O2) synthesis by eosinophils was down-regulated after interaction with C. neofor