The inhibitory effect of ovine recombinant interferon‐gamma on intracellular replication of Toxoplasma gondii

Abstract
A model for the in vitro infection of ovine cells with Toxoplasma gondii tachyzoites has been developed and used to investigate the effect of treatment with ovine recombinant interferon-gamma (ov.rIFN gamma) on parasite replication. Treatment of both alveolar macrophages and fibroblast cells either 24 h pre-infection or 2 h post-infection with ov.rIFN gamma inhibited replication of T. gondii and was quantified by suppression of 3H uracil uptake by the parasite. Replication of T. gondii in the fibroblast cells was significantly inhibited by treatment with 200-300 U/ml ov.rIFN gamma, whereas concentrations as low as 1 U/ml suppressed parasite replication in the alveolar macrophages.