TCL1_71-78 peptide-specific T cells can be generated from lymphoma patients. (A) PBMCs and tumor-infiltrating lymphocytes (TILs) derived from HLA-A2⁺ patients with CLL or FL were stimulated in vitro with TCL1_65-79. After 5 stimulations, IFN-γ production in response to TCL1_65-79 peptide was determined as described in Figure 3A. (B,E) Cytotoxic function of TCL1_65-79 peptide-specific T cells generated as described in panel A was tested against T2 cells pulsed with TCL1_65-79 peptide or HIV Gag_77-85 peptide (B) or primary HLA-A2⁺ or HLA-A2⁻ MCL or FL tumor cells (FL Tu) or tumor-free PBMCs from FL5 patient (FL5-PB) or HLA-A2⁻ MCF-7 cell line (E). (C) Percentage of tetramer positive CD8⁺ T cells in each of the TCL1-specific T-cell lines generated from lymphoma patients is shown. (D) Expression of TCL1 in each of the primary lymphoma samples as determined by flow cytometry is shown. All cytotoxicity assays were performed in triplicate wells, and mean and standard deviation are shown. CLL1-PB-T indicates TCL1-specific CTL generated from peripheral blood T cells of CLL patient 1; FL5-PB-T, TCL1-specific CTL generated from peripheral blood T cells of FL patient 5; and FL5-TILs-T, TCL1-specific CTL generated from tumor infiltrating T cells of FL patient 5.