Identification of a BALB/c H-2L^d gene by DNA-mediated gene transfer

Gene transfer and immunoselection were used in the identification of a BALB/c genomic clone containing an H-2L^d gene (clone 27.5). Transformation of thymidine kinase-negative C3H mouse L cells with the cloned 27.5 DNA together with the herpes simplex virus tk gene produced transformants expressing L^d molecules detected by radioimmune assay with monoclonal hybridoma antibodies to Ld antigens. The foreign L^d gene products expressed by cloned mouse L cell transformants were shown to be virtually indistinguishable from BALB/c spleen L^d molecules by two-dimensional electrophoretic analysis of H-2L^d immunoprecipitates. These results indicate that the genomic clone 27.5 contains a functional BALB/c H-2L^d gene and demonstrate the usefulness of this approach for identifying the gene products encoded by cloned genes which are members of a multigene family. Furthermore, the ability to place cell-surface recognition molecules on the surfaces of foreign cells provides a powerful opportunity for functional analyses of these molecules.