Triggering T cells by otherwise inert hybrid anti-CD3/antitumor antibodies requires encounter with the specific target cell

We have previously demonstrated that H-2Kd-restricted CTL specific for HLA-CW3 or HLA-A24 can recognize synthetic peptides corresponding to residues 170-182 of the HLA molecules. Synthetic oligonucleotides encoding region 170-182 of CW3 or A24 were inserted into the influenza nucleoprotein (NP) gene. We demonstrate herein that P815 (H-2d) cells transfected with the NP-oligo recombinant genes are specifically lysed by HLA-specific Kd-restricted CTL clones. Our results imply that there must be a high degree of flexibility for the expression of T cell epitopes in different molecular contexts.