FIG. 2.
p12I increases IL-2 production by T-cell antigen receptor ligation in the presence or absence of CD28 costimulation. Transduced Jurkat T cells were activated by immobilized anti-CD3 (coated at 5 μg/ml) (A), immobilized anti-CD3 plus anti-CD28 (coated at 5 μg/ml) (B), or PMA plus 2 μM ionomycin (Iono) (C) in 96-well plates. After 24 h at 37°C, IL-2 secreted in the supernatant was measured by ELISA techniques. p12I-transduced Jurkat T cells secreted significantly higher IL-2 than p12(AS)-transduced cells or mock-infected cells in the presence of anti-CD3 with or without anti-CD28 stimulation. ✽, P < 0.05. Data represent mean IL-2 concentrations from triplicate wells. The results are representative of three independent infection experiments. Statistical significance was analyzed by using the Student t test.