The involvement of VCAM-1 and ICAM-1 is confirmed by the high expression of very late antigen (VLA)-4 and lymphocyte function-activated antigen (LFA)-1, their main ligands, respectively, on the immune infiltrates populating MS lesions (Cannella and Raine, 1995; Bö et al., 1996). The gene discussed is VCAM1; the disease is myeloid sarcoma.