Immunogenicity of N-(2-hydroxypropyl)-methacrylamide copolymers—Potential hapten or drug carriers

Abstract

After repeated i.p. immunizations of mice with 10 μg of homopolymer poly (HPMA) no antibodies were detected by the ELISA test. Immunization with copolymer P-Acap-Leu-HMDA leads to a weak antibody response, while immunization with a copolymer with someside chains modified with ARS or FITC groups (P-Acap-Leu-HMDA-ARS or P-Acap-Leu-HMDA-FITC) leads to a significant antibody response detectable by PFC, ELISA and haemagglutination tests. Most of these antibodies are aimed against the modifying haptenic group, a smaller amount against side oligopeptide sequences of the carrier. Intensity of the antibody response depends on: 1) the antigen dose—the optimal dose was 10μg: both the higher (100μg) and the lower doses (1 and 0.1μg) induced considerably lower antibody responses; 2) molar mass of the immunizing fractions—fractions of high molar mass induced up to five times higher responses than those of a low molar mass; 3) the bound haptenic group—the ARS-copolymers induced ten times lower response than the FITC-copolymers. We detected no difference between capacities of the H-2^a, H-2^b and H-2^d haplotypes to react with anti-ARS antibodies after immunization with P-Acap-Leu-HMDA-ARS.