Activation requirement of CD95⁻ T cells.

Data are from a representative experiment of 3 similar experiments. T cells showed dose-dependent proliferative responses to immobilized anti-CD3 mAb. On the contrary, purified CD95⁻ T cells did not respond to increasing doses of anti-CD3 mAb alone and showed an optimal proliferation only when costimulated by immobilized anti-CD28 (1 mg/mL) and anti-CD3 mAb.