Kappa B binding proteins are constitutively expressed in an IL-2 autocrine human T cell line

J Immunol. 1991 Apr 1;146(7):2409-16.


The IL-2 and the IL-2-R alpha genes are both expressed transiently in normal T lymphocytes after Ag or mitogen activation. In contrast, the human T cell line, IARC 301, expresses these two genes constitutively and we have previously demonstrated that its growth depends on the autocrine production of this T cell growth factor and high affinity IL-2R. To dissect the molecular basis for the unusual persistent expression of the IL-2 and IL-2-R alpha genes in these IARC 301 T cells, we have analyzed the interactions of constitutively expressed nuclear proteins with the 5' flanking regions of the IL-2 and IL-2-R alpha genes using both DNase I footprinting and gel retardation techniques. We have found that a region in both genes (-276 to -250 for IL-2-R alpha and -203 to -183 for IL-2), which corresponds to a kappa B enhancer element, is specifically protected by nuclear proteins from IARC 301. In agreement with this finding, both the IL-2 and IL-2-R alpha promoters are active in transient transfection assays in IARC 301 cells. In contrast, mutation of the kappa B enhancer results in markedly attenuated activities of both promoters. Two proteins binding the kappa B sequence, NF-kappa B and KBF1, are constitutively expressed in IARC 301 nuclei and induced by PMA and PHA in Jurkat. They bind to the kappa B motifs with different relative affinities that may reflect their different contribution in the expression of various promoters.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Cell Line
  • DNA-Binding Proteins / physiology
  • Gene Expression Regulation
  • Humans
  • Interleukin-2 / genetics*
  • Molecular Sequence Data
  • NF-kappa B / metabolism*
  • NF-kappa B p50 Subunit
  • Oligonucleotide Probes / chemistry
  • Promoter Regions, Genetic
  • Receptors, Interleukin-2 / genetics*
  • T-Lymphocytes / physiology*
  • Transcription Factors / metabolism


  • DNA-Binding Proteins
  • Interleukin-2
  • NF-kappa B
  • NF-kappa B p50 Subunit
  • NFKB1 protein, human
  • Oligonucleotide Probes
  • Receptors, Interleukin-2
  • Transcription Factors