Preferential expansion of BV8 and BV13 CD8+ T cells after stimulation with CMV
-peptide. Cells were stimulated in vitro for 14 days with CMVNLV-peptide in the presence of IL-2 and autologous, irradiated PBMC. (A) CD8+ T cells were stained with APC-conjugated pentamers containing the CMVNLV-peptide. Representative examples are shown for one young, one middle-aged and one elderly donor directly ex vivo and after 14 days of culture. Percentages of CD8+ CMVNLV-specific T cells are indicated. (B) After 14 days of culture CMVNLV-specific T cells were further purified from the expanded cells using MACS-technology. Spectratyping was performed from PCR-products of 24 individual V beta families for 31 donors (10 young, 7 middle-aged, 14 elderly). In the right panel examples for the different clonality and intensity scores (see Methods) are shown. Clonality and intensity scores are added to obtain a total score. For each BV family the percentage of donors with a total score above 5 is shown.