Proliferation and gene transfer efficiency of purified T-cell populations.

(A) Proliferation of and (B) gene transfer of NIT into T cells of donor U.S. and donor S.B. were compared at different time points after initiation with irradiated autologous EBV-transformed B cells. Cultures were restimulated 24 hours before the assays. Background proliferation of the irradiated BLCL was subtracted from the proliferation value of the stimulated T cells. To standardize the gene transfer procedure, previously frozen supernatant was used, explaining the relatively low gene transfer efficiency in this experiment. Cells, transduced with fresh supernatant as controls, showed a 30% to 50% higher gene expression at all time points.