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The natural killer cell serine protease gene Lmet1 maps to mouse chromosome 10

Journal Article · · Immunogenetics
;  [1]; ; ;  [2]
  1. Austin Hospital, Heidelberg (Australia)
  2. NCI-Frederick Cancer Research and Development Center, Frederick, MD (United States)

Cytotoxic lymphocytes play a key role in immune responses against viruses and tumors. Lymphocyte-mediated cytolysis by both cytotoxic T lymphocytes (CTL) and natural killer (NK) cells is often associated with the formation of membrane lesions on target cells caused by exocytosis of cytoplasmic granule serine proteases and a pore-forming protein, perforin. A variety of granzymes have been found to reside within the cytoplasmic granules of cytotoxic lymphocytes, but unlike perforin, isolated serine proteases are not intrinsically lytic. However, a role for serine proteases in cellular cytotoxicity has been supported by the ability of protease inhibitors to completely abrogate lymphocyte cytotoxicity, and the demonstration that serine proteases can initiate DNA fragmentation in target cells transfected or pretreated with a sublytic concentration of perforin. Granzymes cloned in human, mouse, and rat encode four granzyme activities and all are expressed in either T cells, their thymic precursors, and/or NK cells. In particular, a rat granzyme that cleaves after methionine residues, but not phenylalanine residues and its human equivalent, human Met-ase 1, are unique granzymes with restricted expression in CD3-NK cells. 24 refs., 2 figs.

Sponsoring Organization:
USDOE
OSTI ID:
75574
Journal Information:
Immunogenetics, Journal Name: Immunogenetics Journal Issue: 1 Vol. 41; ISSN 0093-7711; ISSN IMNGBK
Country of Publication:
United States
Language:
English