To expand the spectrum of recognition of effector lymphocytes and to redirect them towards predefined targets, we have altered the specificity of human tumor-infiltrating lymphocytes (TIL) through stable modification with chimeric receptor genes consisting of single-chain antibody variable regions linked to the gamma subunit common to the immunoglobulin (Ig)G and IgE Fc receptors. Using either hapten or ovarian carcinoma-specific monoclonal antibodies, we constructed chimeric receptor genes and retrovirally introduced them into CD8+ TIL. Redirected TIL specifically lysed trinitrophenyl-labeled Daudi or a human ovarian carcinoma cell line (IGROV-1), and secreted granulocyte/macrophage colony-stimulating factor upon stimulation with the appropriate antigen. This strategy may allow new approaches towards the adoptive immunotherapy of cancer in humans.