Transfection of genes for human cell surface antigens identified by monoclonal antibodies

Six murine L cell lines expressing five different human cell surface antigens have been prepared by DNA-mediated gene transfer. Ltk- cells were transfected with calcium phosphate co-precipitates of human genomic DNA and a plasmid containing the Herpes simplex thymidine kinase gene. After HAT selection, transfectants expressing specific cell surface antigens were identified by in situ immune rosetting using monoclonal antibodies. In this way, transfected cell lines expressing the CD9 antigen, the CD31 antigen (two lines), a unique platelet antigen, an X-linked antigen (R1), and a previously unreported monocyte antigen 11D1 were prepared. These cell lines have proved useful in the definitive assignment of monoclonal antibodies to specific CD groups. In addition, they provide a source of mRNA for use in expression cloning of the genes for these antigens.