Studies on Organ Specificity

Abstract

Summary The sera of rabbits immunized with hog thyroid crude saline extract or hog thyroglobulin were studied by gel-diffusion precipitation techniques. Several precipitation lines were discernible by the double diffusion techniques of agarprecipitation in tubes when hog thyroid antisera were tested with hog thyroid extract. The individual precipitation bands were identified by absorption experiments. The antisera were shown to contain antibodies that react only with antigen(s) in hog thyroid extract as well as antibodies that cross-react with antigen(s) in thyroid extracts from other species. In addition, some of the antisera contained antibodies that react with extracts of other hog organs. The nature of the reactions of hog thyroid antisera with hog thyroid extract and thyroid extracts from other species was demonstrated by the Ouchterlony technique of gel precipitation. One of the two lines produced by the reaction of a hog thyroid antiserum (after species-specific antibodies had been absorbed) with hog thyroid extract gave a reaction of partial identity with a single precipitation band produced by the same antiserum with the thyroid extracts of certain other species. Hog thyroid antisera (species-specific antibodies absorbed) gave a single precipitation are with hog thyroid extract and thyroid extracts of other species subjected to electrophoresis. The location of the precipitation are was the same for both the homologous and cross-reactions. The organ-specific thyroid antigens have the same electrophoretic mobility as α-globulins of human serum.