Extracellular activities of human granzymes. I. Granzyme A induces IL6 and IL8 production in fibroblast and epithelial cell lines

Cell Immunol. 1996 Jul 10;171(1):159-63. doi: 10.1006/cimm.1996.0187.


Situated in secretory granules of cytotoxic cells, granzymes are essential for induction of target cell apoptosis with perforin. However, since cytotoxic cells constitutively secrete a portion of their synthesized granzymes, these proteases could mediate extracellular functions independently of their role in the lytic event. Thrombin has been shown to function as an activation molecule by cleaving its receptor. We hypothesize that granzymes may act similarly. In this report, we show that purified human granzyme A can induce human lung fibroblasts to produce IL6 and IL8. Cytokine induction is abrogated by treating the serine protease with the suicide serine protease inhibitor 3,4-dichloroisocoumarin. Other fibroblast lines as well as epithelial cells produced cytokines in response to granzyme A. Our data suggest that granzyme A can function as an activation molecule with potentially important immunoregulatory functions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • Enzyme Activation / immunology
  • Epithelium / drug effects
  • Epithelium / metabolism
  • Extracellular Space / enzymology*
  • Fibroblasts / drug effects
  • Fibroblasts / metabolism*
  • Granzymes
  • Humans
  • Interleukin-6 / biosynthesis*
  • Interleukin-8 / biosynthesis*
  • Lung
  • Serine Endopeptidases / pharmacology*
  • Skin
  • Thrombin / pharmacology


  • Interleukin-6
  • Interleukin-8
  • Granzymes
  • Serine Endopeptidases
  • Thrombin
  • GZMA protein, human