Entamoeba histolytica: induction and isotype analysis of antibody producing cell responses in Peyer's patches and spleen after local and systemic immunization in male and female mice.

The purpose of this work was to determine if anti-amebic antibody producing cell responses could be elicited in Peyer's patches and spleen in mice locally or systemically immunized with glutaraldehyde-fixed trophozoites of Entamoeba histolytica (GFT). The animals were inoculated with either a single or four doses of GFT via intragastric, rectal, and intraperitoneal routes. The anti-amebic antibody producing cell responses were analyzed by a spot forming cell assay (ELISPOT). The kinetics of antibody response revealed that a single dose of GFT by any route evoked anti-amebic responses in Peyer's patches and spleen. Furthermore, antibody producing cells of the three major isotypes were produced in both Peyer's patches and spleen of the mice receiving four doses of GFT, by either local or systemic routes. Our results indicate that immunization with GFT can induce a considerable number of specific antibody producing cells, which seem to remain in the Peyer's patches. After rectal and intraperitoneal immunization, females produced higher anti-amebic responses than males. Since either local or systemic immunization with GFT elicits both mucosal and systemic anti-amebic responses, this strategy should be considered as a promising tool for future elaboration of an anti-amebic vaccine.