title: Histological evaluation of the lesion induced by inoculation of Leishmania mexicana in the cheek pouch of the hamster.
abstract: We have studied the role of the immune response in the morphology of the leishmaniotic granuloma induced in the cheek pouch of hamsters, an immunologically privileged site, after inoculation of 3 x 10(5) Leishmania mexicana. Animals were histologically and immunologically evaluated until 120 days after inoculation. Independent of the time of sacrifice, the animals were always non-reactors to the footpad test (FPT). At histology, the introduction of L. mexicana in the cheek pouch leads to an abscess that evolves to a granulomatous reaction rich in amastigote forms, and later it leads to resolution, even in the absence of immune response detectable by FPT. Our results demonstrate that the development of immune response is not preponderant for the control of infection induced by L. mexicana inoculated subcutaneously in the cheek pouch of the hamster. It also suggests that the macrophages present in the leishmaniotic granuloma are capable of eliminating this parasite, even in the absence of immune response evaluated by FPT.
authors.affiliation: Departamento de Ciências Biológicas, Faculdade de Ciências, Universidade Estadual Paulista, Campus de Bauru, SP, Brasil. sueli@fc.unesp.br
authors.forename: Maria Sueli
authors.initials: MS
authors.lastname: Parreira de Arruda
authors.forename: Maria Esther Salles
authors.initials: ME
authors.lastname: Nogueira
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Bordon
mesh_terms: D000818:Animals; D002610:Cheek; D006224:Cricetinae; D006099:Granuloma / Q000276:immunology / Q000469:parasitology / Q000473:pathology*; D007894:Leishmania mexicana / Q000276:immunology; D016773:Leishmaniasis, Cutaneous / Q000276:immunology / Q000473:pathology*; D008297:Male; D008647:Mesocricetus