Intact RBCs and RBC/T-cell contacts are required for optimal T-cell expansion and survival.

T-cell proliferation was measured 5 days after stimulation in the following conditions: PHA-P, PHA-P plus intact RBCs, PHA-P plus intact RBCs separated by a cell insert, PHA-P plus sonicated RBCs, and PHA-P plus catalase (10 μg/mL). Results show thymidine incorporation (cpm, mean ± SD, n = 3) in the different culture conditions. PHA-P was used at 5 μg/mL.