IFN-α and IL-2 protect the clonal Th2 cells against spontaneous apoptosis.

CD3⁻CD4⁺ cells from hypereosinophilic patient 1 and patient 2 (♦) were cultured in presence of IFN-α (10⁴ IU/mL) (▪) or IL-2 (100 IU/mL) (▴). Cells were recovered after 24, 48, 72, and 96 hours of culture. Apoptotic cells were detected by flow cytometry according to FSC/SSC parameters. Results are the means ± SEM of % apoptotic cells of 5 experiments. *P < .005 as compared with culture without IFN-α or IL-2 (ANOVA test).