Isolation of broadly reactive, tumor-specific, HLA class-I restricted CTL from blood lymphocytes of a breast cancer patient

Blood lymphocytes of a HLA-AZ positive breast cancer patient were stimulate d with either MCF-7 or MDA-MB-231, i.e., HLA-A2-matched allogeneic breast, carcinoma cell lines. Several CD8(+) CTL clones with reactivity against the stimulator cells bur not against K562 were generated. Reactivity could be blocked Rich monoclonal antibody (mAb) W6/32, MA2.1, and/or BB7.2, indicati ng that the clones art HLA-class I and HLA-A2 restricted. The CTL clones ge nerated following stimulation with MCF-7, recognized various other allogene ic HLA-A2(+) tumor cell lines, including breast carcinoma, renal cell carci noma, and melanoma cell lines, but not HLA-AZ- tumor cell lines. The CTL cl ones did nor recognize normal HLA-A2(+) cells including breast epithelial c ells, renal proximal tubular epiehelial cells (PTEC), or EBV-transformed B cells including the autologous EBV cell line. In contrast to the CTL clones induced with MCF-7, the reactivity of the clones stimulated with MDA-MB-23 1, was limited to the stimulator cell MDA- MB-231. Cytotoxicity assays util izing T2 cells loaded with peptides as target cells indicated that none of the examined CTL-epitopes derived from HER-2/neu, Muc-1, Ep-CAM-1, and p53 were recognized by the CTL clones generated. Our findings underscore that b reast cancer is an immunogenic tumor and that HLA-class I-matched allogenei c tumor cells can be used as stimulator cells tu generate rumor-specific CT L from peripheral blood of a breast cancer patient with specificity for an ant;genic determinant that is broadly expressed on tumor cells from various origins or with specificity limited to the breast cancer stimulator cell. Human Immunology 60, 1195-1206 (1999) (C) American Society for Histocompati bility and Immunogenetics, 1999 Published by Elsevier Science Inc.