The major histocompatibility complex of the guinea pig. I. Serologic and genetic studies.

Serologic and genetic studies of the antigens which comprise the guinea pig MHC have demonstrated three distinct but linked genetic regions. Antisera to the B region were raised by cross-immunization of random-bred animals; this region controls antigens B.1, B.2, B.3, and B.4 which behave as alleles at a single locus and which resemble the products of the murine D or K region genes in their tissue distribution and molecular characteristics. Cross-immunization of inbred strain 2 and strain 13 animals, both of which bear the B.1 antigen, leads to sera which identify antigens which resemble the products of the I region of the murine MHC. Specific absorption experiments have demonstrated four distinct I region antigens. In addition to the B and I regions, inbred strain 2, strain 13, and some outbred animals bear an antigen (S.1) which is the product of a third genetic region and which also resembles the murine D or K region gene products in molecular size. The results of these studies should facilitate the use of the guinea pig as an experimental model for studies of genetic control of the immune response and the function of the histocompatibility-linked Ir genes.