Regulation of interleukin 2 receptors on T cells from multiple sclerosis patients.

Receptors for interleukin 2 (IL-2) are absent on resting T lymphocytes and are induced by antigenic and mitogenic stimulation. After a limited time (8-12 days), these receptors on normal T cells are down-regulated despite the presence of receptor-saturating concentrations of IL-2. We report here that both antigen- and mitogen-induced T-cell lines and clones obtained from peripheral blood and cerebrospinal fluid of multiple sclerosis patients show prolonged expression of IL-2 receptors. This expression is coincident with a prolonged responsiveness to the proliferative effects of IL-2. In addition, Leu 3+, IL-2 receptor-positive T-cell clone from the cerebrospinal fluid of a multiple sclerosis patient has been established and maintained for more than 1 year without IL-2. This clone has some morphologic and histochemical properties of T cells transformed or infected by human T-lymphotropic virus type I.