Proliferative capacity of memory CD8⁺ T cells.

<p>(A) C57BL/6 mice were primed with PBS or anti-DEC:OVA+anti-CD40, and boosted with anti-DEC:OVA+anti-CD40 at day 60. At day 2, 4, and 7 after booster immunization, splenocyes were isolated, labeled with CFSE, and then cultured without (B) or with (C) OVA(257-264) peptide. 3 days after in vitro culture, OVA-specific CD8⁺ T cell proliferation was examined by staining splenocytes with anti-CD8 and K^b/OVA257-264 tetramer. (B) Autonomous proliferation of OVA-specific T cells in the absence of OVA peptide. Plots were gated on CD8⁺ cells. Numbers indicate the percentage of tetramer⁺ cells in CD8⁺ cells. (C) Ag-driven proliferation of OVA-specific T cell in the presence of OVA-peptide. Plots were gated on CD8⁺ cells. Numbers indicate the percentage of CFSE low tetramer⁺ cells in CD8⁺ cells.