THE EFFECT OF PEPTIC AND TRYPTIC DIGESTION ON THE ANTIGENICITY OF TRICHINELLA SPIRALIS1

Abstract

Powdered trichinae were digested anaerobically in alkaline-trypsin and acid-pepsin solutions until biuret-negative. The digests were used as antigens, with an undigested control, to sensitize dogs intraven. and subcut. After a suitable time interval, serial skin tests were performed with an undigested Trichinella antigen. Serial flocculation tests were done on sera. The dogs sensitized with digested antigens reacted as strongly as the control animals to skin tests. No difference was noted in the flocculation tests. Acid-pepsin and alkaline-trypsin digestion of Trichinella antigen did not destroy its reactivity for dogs, as measured by skin tests and flocculation tests. A more marked reactivity was noted to skin tests as compared with the flocculation test, suggesting that the same antigen may not be responsible for both reactions. Failure of proteolytic digestion to destroy the antigens suggests that the antigenic fraction of T. spiralis is not solely a protein.