Activation of pro-urokinase by the human T cell-associated serine proteinase HuTSP-1

FEBS Lett. 1990 Jan 15;260(1):141-4. doi: 10.1016/0014-5793(90)80087-y.


The human T cell-associated serine proteinase-1 (HuTSP-1) is expressed by activated T lymphocytes and is exocytosed upon their interaction with target cells. Here, we report that HuTSP-1 is able to convert single-chain human pro-urokinase into the active two-chain enzyme. Time-dependent activation by HuTSP-1 of recombinant human pro-urokinase as well as natural pro-urokinase derived from human melanoma cells was demonstrated in a chromogenic assay specific for active urokinase type plasminogen activator and in immunoblotting experiments revealing the conversion of single-chain into two-chain urokinase. Control experiments excluded plasmin as the activating agent. These data suggest a novel pathway for plasmin generation during T cell-mediated processes such as immune responses and extravasation of immune cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Enzyme Activation
  • Enzyme-Linked Immunosorbent Assay
  • Fibrinolysin / analysis
  • Gene Expression Regulation, Enzymologic*
  • Granzymes
  • Humans
  • Hydrolysis
  • Immunoblotting
  • Melanoma / metabolism
  • Plasminogen Activators / analysis
  • Plasminogen Activators / metabolism*
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / metabolism
  • Serine Endopeptidases / genetics
  • Serine Endopeptidases / metabolism*
  • T-Lymphocytes / immunology
  • Tumor Cells, Cultured
  • Urokinase-Type Plasminogen Activator / biosynthesis
  • Urokinase-Type Plasminogen Activator / metabolism*


  • Recombinant Proteins
  • Granzymes
  • Plasminogen Activators
  • Serine Endopeptidases
  • Fibrinolysin
  • Urokinase-Type Plasminogen Activator
  • GZMA protein, human