Development of autocytolytic activity in patients with autologous GVHD. (A) Maximum autocytolytic (n = 18), anti-T47D (n = 15) and NK cell (n = 18) activity observed during the interval (days 5 through 33) for patients who developed autologous GVHD confirmed by skin biopsy. The results from 6 control ABMT patients not on the autologous GVHD induction protocol are presented for comparison. (B) Peripheral blood lymphocytes from ABMT patients on the autologous GVHD induction protocol were sequentially monitored for their ability to lyse pretransplantation, PHA-stimulated lymphoblasts. The results from 5 representative patients are expressed as the percentage of specific lysis at a 100:1 effector to target cell ratio. Initial time to onset of clinical autologous GVHD confirmed by skin biopsy for patients S.L., J. M., K.S., R. R., and G.T. was on days 17, 10, 10, 12, and 12, respectively. (C) Peripheral blood lymphocytes from patient C.N. who developed autologous GVHD beginning on day 11 were serially monitored for the development of lytic activity against pretransplant lymphocytes, the T47D breast cancer cell line, and the NK target cell line, K562. All lytic assays were performed at a 100:1 effector to target cell ratio with the results expressed as the percentage of specific lysis.