Figure 2. NIK-deficient CD4⁺ T cells respond normally to TCR signaling.

Sorted naive T cells (CD4⁺CD25^–CD44^lo) were stimulated with plate-bound anti-CD3 with (A–C) or without (B and C) anti-CD28. (A) Upregulation of OX40, CD69, and CD25 was assessed on day 2. Gray represents Ox40^–/– (for OX40) or +/+ unstimulated (for CD69 and CD25); thin line represents +/+ stimulated; bold line represents aly/aly stimulated. (B) Proliferation was measured by tritiated thymidine incorporation on days 3 and 4. (C) IL-2 was measured by ELISA of culture supernatants on days 3 and 4. Data (± SD) are representative of 1 (A) or 2 (B and C) independent experiments.