Monoclonal antibody OKT11A inhibits and recombinant interleukin 2 (IL 2) augments expression of IL 2 receptors at a pretranslational level

J Immunol. 1985 Oct;135(4):2478-82.

Abstract

The expression of receptors for interleukin 2 (IL 2) represents a critical event regulating the growth of normal T lymphocytes. We investigated the effects of the inhibitory monoclonal antibody OKT11A (anti-sheep erythrocyte receptor) and of purified recombinant IL 2 (rIL 2) on the expression of IL 2 receptors by activated T cells at both the protein and the mRNA levels. Adding OKT11A antibody (0.5 microgram/ml) to phytohemagglutinin (PHA)-stimulated cultures of human peripheral blood mononuclear cells (PBMC) markedly suppressed cellular proliferation (assessed by [3H]thymidine incorporation) and IL 2 receptor expression (determined by immunofluorescence assay by using the anti-IL 2-receptor antibody, anti-Tac). Northern blot analysis performed with the use of a cDNA probe specific for the human IL 2 receptor gene demonstrated that OKT11A antibody also decreased the accumulation of IL 2 receptor mRNA induced by PHA in PBMC. Purified rIL 2 (10 U/ml) alone had little effect on the expression of IL 2 receptors in unstimulated PBMC cultures. In combination with PHA or with PHA plus OKT11A, however, rIL 2 augmented both the expression of IL 2 receptor protein on PBMC and the accumulation of IL 2 receptor mRNA in PBMC. Adding anti-Tac antibody to PBMC cultures to block the interaction of IL 2 with its receptor diminished the accumulation of IL 2 receptor mRNA induced by PHA. Taken together, these data demonstrate that OKT11A antibody inhibits and IL 2 augments expression of IL 2 receptors on PHA-stimulated T cells, at least in part, at a pretranslational level.

Publication types

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

MeSH terms

  • Adjuvants, Immunologic / physiology
  • Antibodies, Monoclonal / physiology*
  • Autoradiography
  • Binding, Competitive
  • DNA / biosynthesis
  • Fluorescent Antibody Technique
  • Humans
  • Interleukin-2 / genetics
  • Interleukin-2 / physiology*
  • Lymphocyte Activation
  • Protein Biosynthesis
  • RNA, Messenger / metabolism*
  • Receptors, Immunologic / biosynthesis*
  • Receptors, Immunologic / genetics
  • Receptors, Interleukin-2
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism*

Substances

  • Adjuvants, Immunologic
  • Antibodies, Monoclonal
  • Interleukin-2
  • RNA, Messenger
  • Receptors, Immunologic
  • Receptors, Interleukin-2
  • DNA