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The mast cell-restricted tryptase mMCP-6 has a critical immunoprotective role in bacterial infections

Department of Pulmonary Medicine, The University of Texas M. D. Anderson Cancer Center and Center for Lung Inflammation and Infection, Institute for Biosciences and Technology, Houston, Texas 77030, USA.
Journal of Biological Chemistry (Impact Factor: 4.6). 08/2007; 282(29):20809-15. DOI: 10.1074/jbc.M611842200
Source: PubMed

ABSTRACT Although it has been shown that mast cell-deficient mice have diminished innate immune responses against bacteria, the most important immunoprotective factors secreted from activated mast cells have not been identified. Mouse mast cell protease 6 is a tetramer-forming tryptase. This serine protease is abundant in the secretory granules and is exocytosed upon bacterial challenge. Here we have described the generation of a mast cell protease-6-null mouse. Our discovery that mice lacking this neutral protease cannot efficiently clear Klebsiella pneumoniae from their peritoneal cavities reveals an essential role for this serine protease, and presumably its human ortholog, in innate immunity.

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