Summary
It has been shown that the random copolymers GLT, GLA5 and GLPhe are antigenic in rabbits but that the polymers GA and GLA30 are more effective antigens. The introduction of aromatic acid residues did not enhance the antigenicity of G or GL as much as did the introduction of the nonpolar amino acid alanine. The enhanced antigenicity of GLA30 and GA may be ascribed to the increase in the random sequences of polypeptide sequences rather than to the increase in rigidity in the molecules.
Correlations have been shown between the antibody level as determined by PCA and hemagglutination of antigen-coated cells.
The inability of GA and GAT to coat cells and the odd reactions of GAT have been ascribed to the high negative charge density. The possible role of positively charged areas in a molecule in coating of tanned cells has been suggested.
Footnotes
This work was supported by Grants E 3514 and 2E 196 from the National Institutes of Allergy and Infectious Diseases and Contract No. DA-49-193-MD-2113 from the Department of the Army. Office of the Surgeon General.
Presented in part at the annual meeting of the American Association of Immunologists, Atlantic City, New Jersey, 1961, and at the First International Symposium on Poly Alpha Amino Acids, Madison, Wisconsin, June 1961.
