title: V. Effect of enzymes and temperature on the serological activity of the antigen of Fasciola gigantica.
abstract: The partially purified extract of Fasciola gigantica was incubated with enzyme pepsin and samples were taken at different time intervals from 0-24 hours, and tested intradermally for diagnosing bilharziasis. The enzymatic degradation of the protein molecule results in the progressive decrease and eventually the complete disappearance of serological activity. This showed that the protein portion of the antigen was deemed necessary for its activity in intradermal tests for diagnosing schistosomiasis. Amylase, even at a concentration of 5 per cent, did not influence the activity of the partially purified extract of Fasciola gigantica. This showed that the carbohydrate portion of the antigen has no effect on serological activity. The partially purified extract of Fasciola gigantica was subjected to heating at 37 degrees C, 50 degrees C, and 60 degrees C for periods of two, six and 24 hours, and tested intradermally for diagnosing schistosomiasis. Heating decreased the reactivity of the supernatant liquid of the protein solution but did not completely inactivate the serologically active component which is fairly stable at 50 degrees C. Temperatures higher than 50 degrees C started to affect the serological activity of the protein solution. The higher the temperature, the shorter is the time required for the inactivation of the protein. This shows that the serologically active component is protein and not polysaccharide which resists much higher temperatures.
mesh_terms: D000681:Amylases / Q000494:pharmacology*; D000937:Antigen-Antibody Reactions; D000941:Antigens / Q000008:administration & dosage / Q000032:analysis; D002845:Chromatography; D005209:Fasciola / Q000276:immunology*; D006868:Hydrolysis; D006967:Hypersensitivity; D066298:In Vitro Techniques; D007271:Injections, Intradermal; D007428:Intradermal Tests; D009584:Nitrogen / Q000032:analysis; D009696:Nucleic Acids; D010434:Pepsin A / Q000494:pharmacology*; D012552:Schistosomiasis / Q000175:diagnosis*; D012698:Serologic Tests; D012699:Serology; D013053:Spectrophotometry; D013696:Temperature; D014556:Urine / Q000469:parasitology
chemical_list: D000941:Antigens; D009696:Nucleic Acids; D000681:Amylases; D010434:Pepsin A; D009584:Nitrogen