FIG. 2.

Stat6 is activated in the absence of IRS-2. (A) Whole-cell extracts were prepared from enriched T lymphocytes cultured in the presence or absence (−) of IL-4. Activated Stat6 was detected by immunoblotting using an antibody specific for phosphorylated Stat6 (pStat6). The blot was stripped and reprobed with a total Stat6 antibody. The results are representative of three independent experiments. (B) Total splenocytes were cultured overnight in the presence (bold line) or absence (thin line) of IL-4. IL-4Rα expression on B220⁻ cells and major histocompatibility complex class II expression on B220⁺ cells were determined by FACS.