Up-regulation of the raft marker GM1 in TCR-stimulated but not IL-7–stimulated CD4⁺ lymphocytes.

CD4⁺ T cells were cultured for 4 days in the presence of media alone (−), recombinant IL-7 (IL-7), or immobilized αCD3 and αCD28 mAbs. Expression of the ganglioside GM1 was assessed using FITC-conjugated cholera toxin B. Unstained control cells are shown by a filled histogram. CD4 surface staining was performed using an αCD4-PE mAb, and staining of cells in each of the 3 culture conditions is shown. Histograms are representative of data obtained in 3 independent experiments.