The Isolation and Characterization of Two Host Antigens in Hydatid Fluid of Echinococcus Granulosus

Abstract
Summary Hydatid fluids from the cysts of Echinococcus granulosus in man, cattle, sheep and pigs were fractionated by means of a DEAE cellulose column in a stepwise fashion using five phosphate buffers of increasing molarity. Normal human serum was also fractionated. Fractions A and D of human hydatid fluid contain a gamma globulin component and an albumin component, respectively, which were identical in the Ouchterlony reaction with similar components in human serum fractions. In addition to the presence of serum albumin in fraction D of hydatid fluid, an antigen component active with sera from proven cases of hydatid disease was also located in fraction D of pig hydatid fluid. Tests with human serum albumin as antigen in hemagglutination tests with sera from individuals with hydatid disease were negative. Gel-diffusion studies of hydatid fluid and hydatid fluid fractions showed eight antigen-antibody systems in pig hydatid fluid, two in human hydatid fluid, four or five in sheep hydatid fluid and seven in human serum. Studies on the specificity of these antigen-antibody reactions were made.