Cytolytic activity of antileukemia CTL.

(A) CTL lines were derived from PBMCs of BMT recipient (■), from BMCs of BMT donor (▪), and from PBMCs of BMT donor (▨). Cultures were assessed by stimulating responder cells with LB-pulsed DCs as described, followed by weekly restimulations with LBs and autologous irradiated adherent feeder cells. Cultures were tested 7 days after each subsequent stimulation against recipient LB at an effector-target (E/T) ratio of 5:1. The number of cell culture stimulations is represented by II, III, IV, and V. Cytolytic activity of thawed antileukemia CTL, cryopreserved after the fourth restimulation, is represented as IVa. The 4 panels refer to patient 1, patient 2, patient 3, and patient 4 donor-recipient pairs, respectively. (B) CTL lines derived from PBMCs of BMT recipient (■), from BMCs of BMT donor (▪), and from PBMCs of BMT donor (▨) were simultaneously tested against pretransplantation recipient T-PHA blasts or BMRCs (*) at an E/T ratio of 40:1. Ctrl refers to alloreactive CTL lines derived from PBMCs of a healthy volunteer stimulated with autologous DC pulsed with patient 1, patient 2, patient 3, and patient 4 BMRCs, respectively. Alloreactive CTL lines were tested against pretransplantation recipient T-PHA blasts (░) or BMRCs (▥).