H-2L(d) antigen encoded by a recombinant retrovirus genome is expressed on the surface of infected cells

A recombinant murine retrovirus was constructed which contains, within its genome, a truncated version of the gene encoding the murine H-2L(d) major histocompatibility antigen. The H-2L(d) gene, which was inserted 3' of the env splice acceptor site in the recombinant retrovirus MSV-neo, lacked the 5' promoter and TATA sequences and the 3' transcription termination and polyadenylate addition sites of the normal H-2L(d) gene. Transfection of the MSV-neo/H-2L(d) plasmid (pLTV-11) into Y-2 cells resulted in the production of the transmissible recombinant retrovirus LTV-11. Cells infected with LTV-11 virus were resistant to the eucaryotic antibiotic G418 and expressed H-2L(d) on the cell surface. These infected cells contained a viral RNA species which possessed both the H-2L(d) and the neomycin resistance gene sequences but did not contain significant levels of the smaller H-2L(d)-specific mRNA. The H-2L(d) antigen expressed on the surface of infected cells functioned as a target for cytolytic T cells specific for the H-2L(d) antigen.