Human PBMC proliferative response to Leishmania infantum promastigotes is inhibited by anti-IFN-gamma mAb gamma 123.
PBMC from individuals both exposed and non-exposed to leishmaniae proliferative and produce interferon-gamma (IFN-gamma) following stimulation with Leishmania antigens. We studied the kinetics of the proliferative response of PBMC from non-exposed individuals and from patients recovering from visceral leishmaniasis due to Leishmania infantum, using heat-killed stationary-phase promastigotes of L. infantum as stimulating agent. The kinetics of both groups followed a similar temporal pattern, with higher values in the patient's group. Moreover, we observed that in both groups the activation was dose-dependently inhibited following the addition of gamma 123 anti-IFN-gamma monoclonal antibody. These results indicate the need for IFN-gamma in the activation process of PBMC induced by Leishmania antigens and stress the role of IFN-gamma in the immune response to leishmaniasis. The relevance of the elucidation of the immune response mechanism in human leishmaniasis for therapy and vaccination is briefly discussed.
Zucca
M
M
Institute of Microbiology, Torino, Italy.
Novelli
F
F
Giovarelli
M
M
Caramello
P
P
Garotta
G
G
Musso
T
T
Savoia
D
D
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000953:Antigens, Protozoan / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis / Q000276:immunology*; D015847:Interleukin-4 / Q000096:biosynthesis / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology; D007700:Kinetics; D018314:Leishmania infantum / Q000276:immunology*; D007898:Leishmaniasis, Visceral / Q000276:immunology*; D008213:Lymphocyte Activation; D013601:T-Lymphocytes / Q000276:immunology
D000911:Antibodies, Monoclonal; D000953:Antigens, Protozoan; D015847:Interleukin-4; D007371:Interferon-gamma