X chromosome-linked defect of CBA/HN mice in production of tumor-reactive naturally occurring IgM antibodies

Abstract

Tumor-reactive naturally occurring antibodies (NOA) could be readily detected in sera of many mouse strains including congenitally athymic (nude) and germ free (gf) mice. Mice of the CBA/HN strain, however, were found to possess low or undetectable levels of NOA against a wide range of tumor cell lines. Genetic studies indicated that the defect in production of tumor-reactive NOA in CBA/HN mice was largely determined by the absence of an X chromosome-linked gene and is probably similar to the known X chromosome defect of this mouse strain in their antibody response to thymus-independent antigens. In spite of the low level of tumor-reactive NOA, CBA/HN mice do not have a high incidence of spontaneous tumors. These findings suggest that if tumor reactive NOA are involved in immune surveillance against malignancy they are unlikely to act directly in a quantitative manner in the detection and elimination of autochthonous tumors.