Evaluation of Immune Events Ocurring in the Intestinal Mucosae during Trichinella spiralis Infection

COHEN MELINA; NUÑEZ GUILLERMO G.; ROUX MARIA E.; VENTURIELLO STELLA M.

Boston, Massachusetts, USA

Congreso; 14th International Congress of Mucosal Immunology (ICMI 2009); 2009

Society of Mucosal Immunology (SMI)

The protective role of the intestinal immune response remains unclear. The kinetics of cell phenotype, immunoglobulins, cytokines and eotaxin were determined analyzing their correlation with worm expulsion. Wistar rats duodeni were obtained on 1-13 days post-infection (dpi), subjected to the Perfext method to be used in ELISAs or to determine the intestinal adult worm (AW) burdens. Histochemical and indirect immunofluorescence techniques were employed to determine anti-newborn larvae (NBL) immunoglobulins and cell phenotype. a) IgA,IgE,IgG1 and IgG2a anti-muscle larvae excretory-secretory products (ESP) were positive from 1-2dpi. By 6dpi IgG2a negativized, when IgG1 started to increase. b) IgA and IgE anti-AW-ESP were detected on 1dpi and 3 dpi respectively, with a marked peak of IgA on 13dpi. c) Anti-NBL IgE was detected by 6dpi and IgA by 13dpi. d) INFg,TNFa,IL-4,IL-10 and eotaxin were found on 1-6dpi. E)Histopathological changes with a significant early increase of CD4+,CD8aa+,TCRgd+,IgE+,IgA+,eosinophils and mast cells were found. 1-There is an early mixed innate-Th1-Th2 response with important immunohistopathological change finally polarizing to Th2, priming the intestine for AW expulsion. 2-Parasite stage specific IgE suggest a protective role of this immunoglobulin. 3-The increase in the levels of IgA-anti-AW during the late phase of the infection suggests its mucosal homeostatic role.