Expansion of HA-1– and HA-2–specific CTLs. Data represent a theoretical calculation based on the actual expansion rates of the CTLs. The expansion rates of the CTLs were calculated as follows: expansion rate = Total number of the cells after restimulation/no. of restimulated cells. The initial number of responder cells was 5 × 10⁷ and the total yield of CTLs before each restimulation was calculated by multiplying the expansion rate per week with the number of theoretically restimulated cells. (◍,◊) Two HA-2–specific CTLs induced by PBDC; (△) HA-1–specific CTL induced by PBDC; (⧫) HA-1–specific CTL induced by BMDC.