Granzyme A-deficient mice retain potent cell-mediated cytotoxicity

EMBO J. 1995 Sep 1;14(17):4230-9.

Abstract

Granzyme A, a granule-associated serine proteinase of activated cytotoxic T cells and natural killer cells, has been reported to play a critical role in DNA fragmentation of target cells. To address the question of the biological role of granzyme A, we have now generated a granzyme A-deficient mouse mutant by homologous recombination. Western blot analysis, enzyme assays and reverse transcription-PCR confirmed the absence of granzyme A in activated T cells. In addition, deletion of granzyme A does not alter the expression patterns of other granule components, such as granzymes B-G and perforin. Granzyme A-deficient mice are healthy and show normal hematopoietic development. Most notably, their in vitro- and ex vivo-derived cytotoxic T cells and natural killer cells are indistinguishable from those of normal mice in causing membrane disruption, apoptosis and DNA fragmentation in target cells. Furthermore, granzyme A-deficient mice readily recover from both lymphocytic choriomeningitis virus and Listeria monocytogenes infections and eradicate syngeneic tumors with kinetics similar to the wild-type strain. These results demonstrate that granzyme A does not play a primary role in cell-mediated cytotoxicity, as has been assumed previously.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Apoptosis
  • Base Sequence
  • Cytotoxicity, Immunologic
  • DNA Primers
  • Exons
  • Flow Cytometry
  • Gene Expression
  • Granzymes
  • Hematopoiesis / genetics
  • Killer Cells, Natural / enzymology*
  • Killer Cells, Natural / immunology
  • Listeria monocytogenes
  • Listeriosis / immunology
  • Lymphocyte Activation
  • Lymphocytic Choriomeningitis / immunology
  • Lymphocytic choriomeningitis virus
  • Mice
  • Mice, Mutant Strains
  • Molecular Sequence Data
  • Mutagenesis, Insertional
  • Polymerase Chain Reaction
  • RNA, Messenger / analysis
  • RNA, Messenger / biosynthesis
  • Serine Endopeptidases / deficiency*
  • Serine Endopeptidases / genetics*
  • T-Lymphocytes, Cytotoxic / enzymology*
  • T-Lymphocytes, Cytotoxic / immunology
  • Tumor Cells, Cultured

Substances

  • DNA Primers
  • RNA, Messenger
  • Granzymes
  • Serine Endopeptidases