In vitro and in vivo effects of interleukin 2 on the protozoan parasite leishmania.
T cells can have either resistance-promoting or disease-promoting effects in murine cutaneous leishmaniasis. It is known that the adoptive transfer of parasite-specific helper T cells led to an exacerbation of Leishmania-induced lesions. This work presents evidence that lymphokines produced by activated T cells could be involved in this exacerbating process by directly stimulating the parasite growth. In the presence of activated T cell supernatants, the in vitro growth of Leishmania mexicana amazonensis promastigotes was greatly enhanced. This effect was reproduced by addition of recombinant interleukin 2 (IL2). An anti-IL2 antibody partially reversed the stimulatory effect of IL. An in vivo in situ treatment of infected mice with IL 2 led to an exacerbation of the lesions. The increase in footpad swelling after IL2 treatment was correlated with a higher number of parasites per lesion. The protective effect of cyclosporin A against the development of Leishmania infection was abolished by IL2 treatment. As we observed that IL2 has a stimulatory effect on the in vitro Leishmania growth, we speculate that exacerbation of the lesions observed in vivo after IL2 treatment could be partially related with a direct effect of IL2 on the parasite growth.
Mazingue
C
C
INSERUM U167, Institut Pasteur, Lille, France.
Cottrez-Detoeuf
F
F
Louis
J
J
Kweider
M
M
Auriault
C
C
Capron
A
A
D000818:Animals; D003524:Cyclosporins / Q000494:pharmacology; D007376:Interleukin-2 / Q000494:pharmacology*; D007891:Leishmania / Q000254:growth & development / Q000276:immunology* / Q000472:pathogenicity; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011994:Recombinant Proteins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology
D003524:Cyclosporins; D007376:Interleukin-2; D011994:Recombinant Proteins