title: Evidence for negative regulation of T cell growth by low affinity interleukin 2 receptors.
abstract: Two experimental situations have been studied, and the results provide evidence for a negative regulatory role for the low affinity interleukin 2 receptor (LA-IL 2R). The IL 2-dependent T helper cell line L-14, deprived of IL 2, becomes quiescent and expresses comparable numbers of high affinity IL 2R (HA-IL 2R) and LA-IL 2R. After activation by recombinant IL 2, this cell line preferentially expresses LA-IL 2R. The IL 2 responsiveness of the L-14 cell line was found to vary according to the ratio of LA-IL 2R to HA-IL 2R: the relative predominance of the LA-IL 2R coincides with a hyporeactivity of cells to IL 2. In contrast, a predominance of HA-IL 2R is accompanied by an increase in cellular IL 2 reactivity. Treatment of three IL 2-dependent T cell lines (L-14, HT-2, and C30.1) with limited amounts of recombinant IL 2 and moderate concentrations of anti-IL 2R monoclonal antibodies stimulates T cell growth. This treatment was shown to selectively diminish the expression of membrane LA-IL 2R. The stimulation was attributed to the decrease of expression of LA-IL 2R.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D002455:Cell Division; D002999:Clone Cells; D007376:Interleukin-2 / Q000502:physiology*; D008213:Lymphocyte Activation; D051379:Mice; D011971:Receptors, Immunologic / Q000502:physiology*; D015375:Receptors, Interleukin-2; D012995:Solubility; D013601:T-Lymphocytes / Q000166:cytology*; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D007376:Interleukin-2; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2