Dr. Kassai Tibor szerk.: Parasitologia Hungarica 2. (Budapest, 1969)

Parasit Hung. 2. 39-44.1969 Inhibitory Effect of Worm Metabolic Antigen on the Proteolytic Activity of Intestinal Fluid Dr. Tibor KASSAI — Dr. Béla L. TÓTH Helminthological Research Laboratory, Department of Parasitology Veterinary University, Budapest By intraduodenal transplantation of sexually mature worms CHANDLER (1936) established that antigenic secretions and excretions of Nippostrongylus brasiljensis parasitising the intestine can be absorbed and induce an immune response. One might infer, therefore, that certain products of N. brasiliensis escape digestion by inhibiting host proteolytic enzymes, a property that may assist in creating conditions favourable for absorption of immunogenic molecules. Experiments devised to study in vitro the inhibitory effects of metabolic pruducts of N. brasiliensis on host proteolytic enzymes are presented in this paper. Materials and Methods Collection of intestinal fluid

: After 24 hours' starvation 11 rats (200-300 g), were killed without anaesthesia. The small intestine was ligated at both ends, removed from the body and 4 ml warm (37°) physiological salt solution injected into the lumen. After mild massage the ligatures were cut and the fluid collected for centrifneration

. From the supernatant fluid dilutions of 1:25, 1:50 and 1:100 were made.