INCREASED LEVELS OF ANTIBODIES TO IFN-GAMMA IN HUMAN AND EXPERIMENTALAFRICAN TRYPANOSOMIASIS

In African trypanosomiasis the occurrence of antibodies to interferon- gamma (IFN-gamma) was studied in both humans and experimental rats. Se ra from patients infected with Trypanosoma brucei gambiense showed inc reased levels of antibodies to IFN-gamma as compared with controls fro m the same regions in Africa. In Sprague-Dawley rats infected with Try panosoma brucei brucei an early appearance of IFN-gamma-producing sple en cells was observed, followed by an increase in levels of antibodies against IFN-gamma in the sera. Previously, IFN-gamma has been found t o play a crucial role in trypanosome infections in rats by promoting p roliferation of Trypanosoma brucei brucei. The appearance of antibodie s to IFN-gamma in humans, as in rats, indicates that this cytokine is produced also in the human infection. Its parasitic growth-stimulating and pathophysiological effects on the organism may be reduced by the antibodies.