Monoclonal Antibodies Specific for the Mouse IgG 1 Allotypic Determinants: Reactivity With Inbred and Outbred Mice

Abstract

C57BL/6J mice were immunized with an affinity purified monoclonal antibody (IgG₁) derived from BALB/c mice and their spleen cells were fused with the mouse myeloma X63.Ag8.653. Two monoclonal antibodies (3A9, γ₁,kappa and 1C10, γ₁,kappa) derived from separate fusions were originally found to react with BALB/c monoclonal antibodies expressing a γ₁ heavy chain isotype but not with other heavy chain isotypes. The results from strain distribution reactivity patterns indicate that these antibodies recognize determinants coded by the allotype locus designated Igh-4^a. In a survey of 22 different inbred or congenic strains of mice, no additional polymorphism associated with this locus has been detected. However, allelic polymorphism of the γ₁ heavy chain allotype does exist in the wild mouse population. The 3A9 and 1C10 antibodies recognize the same determinants (i.e., specificity 1) associated with Igh-4^a allotype.