Upregulation by retinoic acid of interleukin-2-receptor mRNA in human T lymphocytes

Cell Immunol. 1993 Jan;146(1):28-37. doi: 10.1006/cimm.1993.1003.

Abstract

It was previously demonstrated that retinoic acid (RA) can enhance the functional responses of human T lymphocytes by increasing surface IL-2R alpha chain protein expression on proliferating T blasts, resulting in augmented IL-2-dependent growth. In the present study, we used IL-2-maintained lymphoblasts generated from human thymocytes to show that RA enhancement of IL-2R alpha is accompanied by an increase in steady-state levels of IL-2R alpha mRNA. This increase occurred within 1 hr after the addition of RA to the culture and was inhibited by the presence of the protein synthesis inhibitor cycloheximide. RA did not alter the stability of either IL-2R alpha on the cell surface or IL-2R alpha mRNA, suggesting regulation by RA at the level of transcription. This contention was supported by the demonstrated ability of RA to activate the IL-2R alpha promoter in a chloramphenicol acetyltransferase plasmid construct that was transfected into the blast cells. In addition to inducing IL-2R alpha expression, RA also increased the surface expression and mRNA levels of IL-2R beta, the 75-kDa component of the IL-2 receptor that mediates IL-2 signal transduction. These new findings showing regulation by RA of both IL-2R alpha and IL-2R beta suggest multiple pathways by which this retinoid can modulate functional IL-2 receptors.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Cells, Cultured / drug effects
  • Cycloheximide / pharmacology
  • Humans
  • RNA / biosynthesis
  • Receptors, Interleukin-2 / biosynthesis*
  • T-Lymphocytes / drug effects*
  • T-Lymphocytes / immunology
  • Thymus Gland / cytology
  • Tretinoin / pharmacology*
  • Up-Regulation

Substances

  • Receptors, Interleukin-2
  • Tretinoin
  • RNA
  • Cycloheximide