Endogenous BCL11B associates with the IL-2 promoter in Jurkat and primary CD4⁺ T cells. Immunoprecipitation (IP) of chromatin from Jurkat cells (A) or primary CD4⁺ T cells (B) stimulated with PMA/ionomycin (lanes 5 and 6) or no stimulation (lanes 3 and 4) using anti-BCL11B (lanes 4 and 6) or nonspecific (lanes 3 and 5) antibodies. Eluted DNA was analyzed by PCR using human (A) or mouse (B) IL-2 promoter-specific primers or actin promoter primers covering the indicated regions. In each case, lanes 1 and 2 represent input from untreated and treated cells, respectively.