Fig 5. Proliferative capacity of Ag-specific T cells in young and aged mice after 8-wk post- immunization with LdCen-/-.

Splenocytes were isolated from each naive, 8-wk post immunized (Imm), naive and 4-wk post challenged (Naive Chal), 8-wk post immunized and 4-wk post challenged (Imm Chal) mouse; stained with CFSE, and stimulated in vitro with FTAg for 5 days. (A) Cells were analyzed by flow cytometry, in which CFSE dilution on particular gated cells was used as the readout for Ag-specific proliferation. (B) Percentages of gated CD3, CD4, and CD8-proliferated T cells were calculated. The data presented are representative of two independent experiments with similar results and six mice in each group. Mean and SEM of each group were shown. *p < 0.05, **p < 0.005. Black bar indicates young mice and white bar indicates aged mice.