Effects of multiple signaling inhibitors on adhesion of peripheral ATL cells to IL-1–activated HUVECs and purified ICAM-1. ATL cells were pretreated with or without indicated concentrations of multiple inhibitors of intracytoplasmic signaling to purified ICAM-1 (a) and IL-1–activated HUVECs (b). Adhesion assay was performed as described in the Materials and Methods. Data are expressed as the mean percentage of bound cells from a representative experiment of 4 patients.