Selective release of a processed form of interleukin 1 alpha

Cytokine. 1994 Nov;6(6):597-601. doi: 10.1016/1043-4666(94)90046-9.

Abstract

Interleukin 1 alpha (IL-1 alpha) is synthesized as a 33 kDa form and proteolytically processed into a 17 kDa form. Although IL-1 alpha has no signal peptide, it is released from cells. To investigate the relationship between the processing and release of IL-1 alpha, human bladder carcinoma cells (HTB9 5637) which express IL-1 alpha constitutively, were treated with calcium ionophore (A23187). A23187 induced the processing of 33 kDa IL-1 alpha and selectively released processed 17 kDa IL-1 alpha, without any change in the release of 33 kDa IL-1 alpha. When extracellular calcium was chelated by EGTA, or when intracellular calpain was inhibited by the cell-permeable cysteine-protease inhibitor, E64d, the processing of 33 kDa IL-1 alpha was significantly blocked, the release of 33 kDa IL-1 alpha being unchanged. These results indicate that the release of IL-1 alpha was accompanied by the processing of 33 kDa IL-1 alpha.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calcimycin / pharmacology
  • Calcium / metabolism
  • Calpain / antagonists & inhibitors
  • Cell Line
  • Cysteine Proteinase Inhibitors / pharmacology
  • Egtazic Acid / pharmacology
  • Gene Expression / drug effects*
  • Humans
  • Interleukin-1 / biosynthesis*
  • Interleukin-1 / metabolism
  • L-Lactate Dehydrogenase / analysis
  • Leucine / analogs & derivatives
  • Leucine / pharmacology
  • Methionine / metabolism
  • Molecular Weight
  • Protein Processing, Post-Translational / drug effects
  • Sulfur Radioisotopes
  • Tumor Cells, Cultured
  • Urinary Bladder Neoplasms

Substances

  • Cysteine Proteinase Inhibitors
  • Interleukin-1
  • Sulfur Radioisotopes
  • Calcimycin
  • Egtazic Acid
  • Methionine
  • L-Lactate Dehydrogenase
  • Calpain
  • Leucine
  • aloxistatin
  • Calcium