QUANTITATIVE CHEMICAL STUDIES ON HEMOLYSINS : I. THE ESTIMATION OF TOTAL ANTIBODY IN ANTISERA TO SHEEP ERYTHROCYTES AND STROMATA

1. Total antibody in hemolysins may be estimated from the nitrogen added to sheep stromata suspensions. 2. The method is applied to a number of hemolysins and a correlation, valid to within 20 per cent, established between hemolytic titer and total antibody. 3. When stromata combine with antibody in the presence of guinea pig complement they may take up at least 80 per cent of their weight of complement combining component(s)

QUANTITATIVE EXPERIMENTS WITH ANTIBODIES TO A SPECIFIC PRECIPITATE. I

1. Rabbits were injected with the washed specific precipitate from Type II antipneumococcus horse serum. Antibody in the resulting antiserum was determined by the quantitative agglutinin method using various specific precipitates as antigens. 2. Suspensions of Types I and II antipneumococcus horse specific precipitates, as well as the specific precipitates derived from Type VIII Pn (anti-C portion), and H. influenzae horse antisera were found to remove the same amount of antibody from the immune rabbit serum. 3. Purified antibody solutions prepared by dissociation methods from Types I and II antipneumococcus horse sera were found to remove the same quantity of antibody as did the homologous specific precipitates. 4. Specific precipitates from anti-crystalline egg albumin and anti-diphtheria horse sera were found to remove only a fraction of the antibody. The reasons for this are discussed. 5. A specific precipitate prepared from pepsin-digested Type I anti-pneumococcus horse serum removed all of the antibody to the homologous antigen from the rabbit anti-precipitate serum, but followed a different quantitative course. 6. From the quantitative course of these reactions and from experiments with specific precipitates from anti-Pn rabbit and pig sera it is concluded that the only antigenic specificity demonstrable for the antibodies investigated was that due to their common origin, and that the groupings responsible for their antibody function constitute either a small part of the total protein molecule or else are non-antigenic

QUANTITATIVE EXPERIMENTS WITH ANTIBODIES TO SPECIFIC PRECIPITATES. II

1. Antisera have been produced in chickens with specific precipitates from Type II pneumococcus horse and rabbit antisera. 2. Specific precipitates from anti-Types I and II pneumococcus horse sera removed the same amount of antibody from the chicken anti-horse specific precipitate serum. Specific precipitates from horse antisera to diphtheria toxin and to crystalline egg albumin removed about one-half of the antibody. 3. Specific precipitates from anti-egg albumin, antipneumococcus C substance, and anti-Type II pneumococcus rabbit sera removed the same amount of antibody from the chicken anti-rabbit specific precipitate serum. 4. No antibody was removed from the chicken anti-horse specific precipitate serum by rabbit specific precipitates or from the chicken anti-rabbit specific precipitate serum by horse specific precipitates. 5. It is concluded that the antigenic specificities of antibodies from the horse and rabbit are not influenced by their particular antibody functions