Altered polyvinylpyrrolidone clearance and immune responsiveness caused by small dietary changes.

The introduction of 25 mg of a new protein antigen into the diets of mice produced transient increases in PVP clearance which reached a maximum 60 hr after the change of diet and had disappeared by 4 days. At the same time the immune responsiveness to unrelated antigens given parenterally was also raised transiently, reaching a peak 5 days following the change and disappearing by 7 days. In contrast the responsiveness to the fed antigen was diminished.