ASCARIS-SUUM . IMMUNE REACTIONS IN MICE .1. LARVAL METABOLIC AND SOMATIC ANTIGENS

The immunologie activity of somatic and metabolic antigens derived from second and third stage Ascaris suum larvae was studied in mice. The results demonstrate that metabolic antigens harvested from third stage A. suum larvae in vitro were capable of inducing resistance to reinfection almost comparable to the immunity stimulated by a combined primary and rechallenge infection. The nonviable metabolic antigen(s) did not appear to be adversely affected by lyophilization. Third stage larvae, recovered from the lungs of infected mice, were cultured for 5 days in Eagle's Minimum Essential Medium, and supplementation with protein did not seem to improve the yield of metabolic antigen(s). © 1969.