High level stable expression of human interleukin-2 receptors in mouse cells generates only low affinity interleukin-2 binding sites.

A bovine papilloma virus-derived vector was used to direct the high level expression in mouse C127 cells of three different cDNAs encoding the human interleukin-2 receptor. These were: the previously described cDNA clone isolated from the T-cell lymphoma, HUT-102; a cDNA clone isolated from mitogen-activated, normal peripheral blood T cells; and an altered version of the HUT-102 receptor in which Ser247, believed to be the site of protein kinase C-mediated phosphorylation, has been changed to an Ala residue. Fluorescence-activated cell-sorting using a monoclonal antibody directed against the human IL-2 receptor was used to derive stable lines of C127 cells expressing from 2-6 X 10(6) IL-2 binding sites per cell. However, all of these receptors bound IL-2 with low affinity.