Article

In vivo protective effect of the lectin from Canavalia brasiliensis on BALB/c mice infected by Leishmania amazonensis.

Serviço de Imunologia, Universidade Federal da Bahia, Brazil.
Acta Tropica (impact factor: 2.72). 03/1996; 60(4):237-50. pp.237-50
Source: PubMed

ABSTRACT In vivo administration of Canavalia brasiliensis lectin (at the time of infection, or maintained throughout the infection) reduced the lesions of highly susceptible BALB/c mice infected by Leishmania amazonensis. At the doses used C. brasiliensis lectin (ConBr) does not interfere with penetration or fate of Leishmania in the macrophages in vitro. Since Interferon-gamma (IFN-gamma) is the major macrophage activating factor, and considered a critical element in the successful immune response against leishmaniasis, we explored its participation in this phenomenon. ConBr either in vivo or in vitro induced IFN-gamma production in normal or in leishmania-infected BALB/c mice. However we were unable to change the course of disease by in vivo IFN-gamma administration (although IFN-gamma preparations were effective in inducing a leishmanicidal effect in vitro on L. amazonensis-infected peritoneal macrophages). Additionally, IFN-gamma neutralization with anti-IFN-gamma monoclonal antibody did not alter the protection conferred by ConBr administration. These data show that lectin administration in vivo is protective in the otherwise unchecked L. amazonensis infection of BALB/c mice, and suggest that such effect is not mediated by IFN-gamma.

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    Kelany S Nascimento, P A J Rosa, K S Nascimento, B S Cavada, A M Azevedo, M R Aires-Barros
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Keywords

anti-IFN-gamma monoclonal antibody
 
BALB/c mice
 
C. brasiliensis lectin
 
Canavalia brasiliensis lectin
 
ConBr administration
 
critical element
 
IFN-gamma
 
IFN-gamma neutralization
 
IFN-gamma preparations
 
L. amazonensis-infected peritoneal macrophages
 
Leishmania amazonensis
 
leishmania-infected BALB/c mice
 
leishmanicidal effect
 
major macrophage activating factor
 
successful immune response
 
susceptible BALB/c mice
 
unchecked L. amazonensis infection
 
vitro induced IFN-gamma production
 
vivo administration
 
vivo IFN-gamma administration