Recent advances in the search for new drugs for treatment of toxoplasmosis

Department of Immunology & Infectious Diseases, Research Institute, Palo Alto Medical Foundation, Palo Alto, California, USA; Department of Medicine, Division of Infectious Diseases, Stanford University School of Medicine, Stanford, California, USA
International Journal of Antimicrobial Agents (Impact Factor: 4.42). 02/1992; DOI: 10.1016/0924-8579(92)90002-9

ABSTRACT Although the combination of pyrimethamine with a sulfonamide is still very effective for treatment of toxoplasmosis the use of these two drugs immunocompromised individuals, particularly AIDS patienst, often results in a remarkable incidence of adverse reactions. There is, therefore, an urgent need for alternative drugs and newer therapeutic regimens for treatment of human toxoplasmosis. In this review, the in vitro and in vivo activities of a number of new drugs and new therapeutic regimens that have shown promising results in vartious experimental models for toxoplasmosisared discussed.

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    ABSTRACT: To investigate the role that cytokines may have in the development of toxoplasmic encephalitis (TE), the levels of gamma interferon (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), interleukin-12 (IL-12 ]p40[), IL-10, IL-6, IL-4, and IL-2 in serum were examined in CBA/Ca mice infected with a type II strain (ME49 or FORT) of Toxoplasma gondii. These strains caused severe (ME49) or mild (FORT) TE in CBA/Ca mice. From weeks 1 to 8 of infection, the levels of IL-6, IL-10, IL-12, IFN-gamma, and TNF-alpha in serum were significantly higher in the ME49-infected mice than in the FORT-infected mice, suggesting a role for these cytokines in the severity of TE in CBA/Ca mice. Since the ME49 and FORT strains are of the same type, our results suggest a role for the parasite in the development of severe TE through the increased production of proinflammatory cytokines and indicate that not all type II strains cause TE.
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