Ex vivo and in vivo biological behavior of Leishmania (Viannia) shawi.
Since the first description of Leishmania (Viannia) shawi, few studies were performed with this parasite. In the present work, the in vivo and ex vivo behavior of L. (Viannia) shawi infection was studied using murine model. Peritoneal macrophages from BALB/c and C57BL/6 mice were infected with promastigotes in the stationary phase of growth; after 24 h, the infection index and nitric oxide (NO) levels in the supernatant of the cultures were analyzed. BALB/c and C57BL/6 mice were infected into the hind footpad, and at each 2 weeks, mice were sacrificed, and the histological changes of the skin inoculation site, parasitism, and humoral immune responses were evaluated during 8 weeks. Ex vivo experiments showed that macrophages of BALB/c presented higher infection index and lesser NO levels than macrophages of C57BL/6. In vivo experiments showed that BALB/c presented higher lesion size than C57BL/6 mice; similarly, the histopathological changes and the parasitism in skin were more exacerbate in BALB/c mice. In draining lymph nodes, the main change was increase of germinative centers, and parasites were detected from 6 weeks pi onwards in both mice strain. IgG was detected in BALB/c mice from 4 weeks, while in C57BL/6, from 6 weeks pi onwards. Taken together, these results indicate that BALB/c showed a classical behavior of susceptibility when compared to C57BL/6 mice.
Passero
Luiz Felipe Domingues
LF
Laboratório de Patologia de Moléstias Infecciosas (LIM-50), Depto. de Patologia, Universidade de São Paulo, São Paulo, SP, Brazil. felipepassero@usp.br
Sacomori
Juliano V
JV
Tomokane
Thaíse Yumie
TY
Corbett
Carlos Eduardo Pereira
CE
da Silveira
Fernando Tobias
FT
Laurenti
Márcia Dalastra
MD
D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D002478:Cells, Cultured; D004195:Disease Models, Animal; D006651:Histocytochemistry; D007074:Immunoglobulin G / Q000097:blood; D007150:Immunohistochemistry; D007891:Leishmania / Q000254:growth & development* / Q000276:immunology*; D007896:Leishmaniasis / Q000469:parasitology* / Q000473:pathology*; D008198:Lymph Nodes / Q000469:parasitology / Q000473:pathology; D017737:Macrophages, Peritoneal / Q000469:parasitology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008853:Microscopy; D009569:Nitric Oxide / Q000378:metabolism; D012867:Skin / Q000469:parasitology / Q000473:pathology
D000913:Antibodies, Protozoan; D007074:Immunoglobulin G; D009569:Nitric Oxide