Fig. 2.

In vitro anti-apoptotic effect of IL-12 on CD8⁺ CD62L^hi cells. OT-1 cells were primed with or without 10 ng/ml of IL-12. Cells were harvested at day 5 and 7 after priming and stained with a mixture of mAbs against Vα2, CD62L and Annexin-V. Cells positive for Vα2 were assayed for CD62L and annexin-V binding (a). Expression of caspase-3, caspase-8, Bax, and Bad was determined on sorted OT-1⁺CD62L^lo/IL-12 or OT-1⁺CD62L^hi/IL-12 at day-5 after priming by real-time PCR (b). Results are presented as the mean normalized expression which is the number of transcripts per 10³ copies of β-actin ± SEM