Figure 7.
Adoptive transfer of HSV-TK–modified T cells results in the induction of a durable memory T-cell response. Samples of PBMCs were obtained from UPN 1574 more than 7 years after HSV-TK–modified DLI, stained with anti-CD8 and anti-CD62L mAbs, and separated by fluorescence-activated cell sorting (FACS) in a CD8+CD62L+ and CD8+CD62L– fraction. These fractions were then incubated with medium alone or stimulated for 6 hours with a peptide mix consisting of the 6 candidate 15-mer peptides as described in “Patients, materials, and methods.” After 6 hours of stimulation, cells were then stained with FITC-coupled anti–IFN-γ and PE-Cy7–coupled anti-CD8 mAbs and examined by flow cytometry. Cells were gated to identify CD8+ T cells and assessed for cytokine production.