Complementary genes controlling immune response to theta-AKR antigen in mice.

Abstract

The primary response of mice to ϑ-AKR antigen was measured by means of plaque assay detecting cells producing antibodies lytic for AKR thymocytes (PFC). It was found that 3 of 12 different F1 hybrids produced significantly more PFC than either parental strain. In segregating populations of C57BL/6J and DBA/2J mice, H-2 homozygotes responded like parental mice, whereas most but not all H-2 heterozygotes responded like F1 hybrids. In the F2 population 7% and in the backcross population to C57BL/6J parent 20% of H-2 heterozygotes responded like parental mice. On the basis of experimental data, a hypothesis was advanced that thre eloci in the IXth linkage group are involved in genetic control of the response to ϑ-AKR antigen. Each locus has at least two alleles, one dominant and one recessive. Dominant alleles complement each other which explains why the response to certain F1 hybrids is higher than the response of their parents. Two of three hypothetical loci are closely linked to each other as well as to the H-2 complex and might be considered components of the Ir-1 system.