Interferon induction in rabbits after intraduodenal administration of a phosphorylated glucomannan-protein fraction of the cell wall of Candida albicans

The aim of this work was to demonstrate whether a glucomannan protein fraction (GMP) of Candida albicans cell wall could induce interferon after intraduodenal administration in normal rabbits and rabbits immunized against C. albicans. For this purpose we collected simultaneously plasma and abdominal lymph for 10 h after the administration of the inducer. We observed a peak of antiviral activity in the lymph 4 h after intraduodenal administration of 20 mg GMP dissolved in saline to 6 normal rabbits. Immunized rabbits (anti-GMP titres greater than 1024) responded earlier (peak after 2 h) and more intensely; analysis of the values of the areas under the curve indicated that the IFN response in the lymph of immunized rabbits was significantly higher (P less than 0.0025) than in normal rabbits. Antiviral activity was absent in plasma in all cases. Preliminary characterization of the IFN activity has shown it to be trypsin-sensitive, acid and heat stable, and species-specific.