Effect of rIFN-gamma and IL-2 treatments in mouse and nude rat infections with Toxoplasma gondii.
Mice and nude rats lethally infected with T. gondii and treated with recombinant rat interferon-gamma (rIFN-gamma) or recombinant human interleukin-2 (rIL-2) were protected against death, when compared with untreated infected controls. In mice rIFN-gamma and rIL-2 played an important role in "prophylactic treatment", but not in "curative therapy". The survival rate was 42% in mice treated with 3 doses of 20,000 U of rIFN-gamma at days -2, -1, 0 before challenge and up to 66% in mice treated with 3 doses of 10,000 U of rIFN-gamma at days -2, 0, +2 before and after infection. Whereas the survival rate was 33% in mice that received 3 doses of 500 U rIL-2 at days -2, -1, 0 before infection, or -2, 0, +2 before and after infection respectively, up to 50% of the mice treated with 3 doses of 1,000 U rIL-2 at days -2, -1, 0 survived. In nude rats rIFN-gamma had a slight effect in "prophylactic treatment", whereas rIL-2 was active only in "curative treatment". The survival rate was 25% both in nude rats treated with doses of 400,000 U of rIFN-gamma at days -3, 0 before challenge, or with doses of 5,000 U of rIL-2 at days +2, +6, +9 after infection. These results lead us to hypothesise that the mechanism by which the lymphokine treatment exerts a protective effect on Toxoplasma infected mice is different from that on nu/nu rats. We conclude that these cytokines may play a notable role in modulating the host's immune defence against T. gondii infection.
Benedetto
N
N
Unité Mixte Institut National de la Santé et de la Recherche Médicale, Institut Pasteur, Lille, France.
Auriault
C
C
Darcy
F
F
Lando
D
D
Watier
H
H
Capron
A
A
D000818:Animals; D016867:Immunocompromised Host; D007155:Immunologic Factors / Q000494:pharmacology / Q000627:therapeutic use*; D007371:Interferon-gamma / Q000494:pharmacology / Q000627:therapeutic use*; D007376:Interleukin-2 / Q000494:pharmacology / Q000627:therapeutic use*; D008213:Lymphocyte Activation / Q000187:drug effects; D008262:Macrophage Activation / Q000187:drug effects; D008297:Male; D051379:Mice; D051381:Rats; D011916:Rats, Inbred F344; D011923:Rats, Nude / Q000276:immunology; D011994:Recombinant Proteins; D014124:Toxoplasmosis, Animal / Q000276:immunology / Q000517:prevention & control / Q000628:therapy*
D007155:Immunologic Factors; D007376:Interleukin-2; D011994:Recombinant Proteins; D007371:Interferon-gamma