Lck-deficient Th2 skewed cells produce Th2 cytokines IL-10, IL-13, and IL-5. A, lck−/− Th2 cells express IL-10 and IL-13. CD4+CD62L+ T cells were stimulated under Th1 and Th2 conditions for 7 d and IL-13 and IL-10 (upper panels), and IL-4 and IFN-γ (lower panels) were analyzed by ICCS. Cells were initially gated on CD4 expression. B, lck−/− Th2 cells express IL-5. CD4+ T cells were stimulated under Th2 conditions for 7 d, and IL-5 expression was detected by a mouse IL-5 secretion assay (upper panels), and IL-4 and IFN-γ were measured by ICCS (lower panels). The shaded peaks in the IL-5 plots represent the no stimulation control, and the line represents the stimulated sample. The cells were initially gated on CD4 expression. The results are representative of two experiments.