Map. Oliveira et al., Leishmania sp: Comparative study with Toxoplasma gondii and Trypanosoma cruzi in their ability to initialize IL-12 and IFN-g synthesis, EXP PARASIT, 95(2), 2000, pp. 96-105
Oliveira, M. A. P., Santiago, H. C., Lisboa, C. R., Ceravollo, I. P., Trinc
hieri, G., Gazzinelli, R. T, and Vieira, L,. Q. 1000. Leishmania sp: Compar
ative study with Toxoplasma gondii and Trypanosoma cruzi in their ability t
o initialize IL-12 and IFN-gamma synthesis. Experimental Parasitology 95, 9
6-105. We compared in vitro and in vivo induction of IL-12 (p40) and IFN-ga
mma by mouse cells stimulated with Toxoplasma gondii, Trypanosoma cruzi, an
d different species of Leishmamia. Spleen cells cultured in vitro with T. c
ruzi or T. gondii, but not with Leishmania produced IL-12 (p40) and IFN-gam
ma. Accordingly, IL-12 (p30) was produced by macrophages stimulated in vitr
o with live T.cruzi or T. gondii or membrane glycoconjugates obtained from
trypomastigotes or tachyzoites. No IL-12 production was detected when macro
phages were stimulated with live parasites or glycoconjugates from Leishman
ia, regardless of priming with IFN-gamma. In vivo, only T. cruzi and T. gon
dii induced the synthesis of IL-12 and IFN-gamma by mouse spleen cells afte
r intraperitoneal injection of parasites. When injected subcutaneously, liv
e Leishmania sp. induced IL-12 (p40) and IFN-gamma production by draining l
ymph node cells, albeit the levels were slightly lower than those induced b
y infection with T. gondii or T. cruzi using the same route. Together our r
esults indicate that under different conditions, the intracellular protozoa
7 gondii and 7 cruzi are more potent stimulators of IL-12 and IFN-gamma sy
nthesis by host immune cells than parasites of the genus Leishmania. (C) 20
00 Academic Press.