Histological evaluation of the lesion induced by inoculation of Leishmania mexicana in the cheek pouch of the hamster

• Published in: Revista da Sociedade Brasileira de Medicina Tropical Vol. 35; no. 4; pp. 293 - 297
• Main Authors: Parreira de Arruda, Maria Sueli, Nogueira, Maria Esther Salles, Bordon, Ana Paula
• Format: Journal Article
• Language: English
• Published: Brazil Sociedade Brasileira de Medicina Tropical 01-08-2002; Sociedade Brasileira de Medicina Tropical - SBMT; Sociedade Brasileira de Medicina Tropical (SBMT)
• Subjects: Animals; Cheek; Cheek pouch; Cricetinae; Experimental leishmaniasis; Granuloma - immunology; Granuloma - parasitology; Granuloma - pathology; Histology; Immune response; Leishmania mexicana; Leishmania mexicana - immunology; Leishmaniasis, Cutaneous - immunology; Leishmaniasis, Cutaneous - pathology; Male; Mesocricetus; Parasites; TROPICAL MEDICINE; Leishmaniose experimental; Cheek pouch; Bolsa jugal do hamster; Experimental leishmaniasis; Leishmania mexicana
• DOI: 10.1590/s0037-86822002000400003
• EISSN: 0037-8682; 1678-9849

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.