Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2000-3-9
pubmed:abstractText
Dipeptidyl peptidase I (DPPI) is a cysteine protease found in many tissues, including the lung. Major cell types expressing DPPI in vitro include myelomonocytic cells, cytotoxic T cells, and mast cells. After activation and degranulation, cytotoxic T cells and mast cells secrete DPPI. With a goal of clarifying possible roles for DPPI in lung diseases, we sought to identify cells expressing DPPI in lung tissue, hypothesizing that lung mast cells are major producers of DPPI and that secreted DPPI cleaves extracellular matrix proteins. To address these hypotheses, we used immunohistochemical techniques to localize DPPI in normal dog airways, lung, and cultured mast cells, and we used purified DPPI to examine cleavage of matrix-associated proteins in vitro. We found that mast cells are the major identifiable source of DPPI in airways and that macrophages are the major source in alveoli. Within mast cells, DPPI localizes to cytoplasmic granules. We also found that DPPI endoproteolytically cleaves the extracellular matrix proteins fibronectin and collagen types I, III, and IV. The finding of DPPI in airway mast cells and its cleavage of matrix proteins suggest the possibility that DPPI plays a role in mast cell-mediated turnover of matrix proteins and in airway remodeling of chronic airway diseases such as asthma.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1044-1549
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
183-90
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Dipeptidyl peptidase I cleaves matrix-associated proteins and is expressed mainly by mast cells in normal dog airways.
pubmed:affiliation
Department of Medicine and Cardiovascular Research Institute, University of California, San Francisco, California 94143-0911, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't