title: Mast cells produce novel shorter forms of perlecan that contain functional endorepellin: a role in angiogenesis and wound healing.
abstract: Mast cells are derived from hematopoietic progenitors that are known to migrate to and reside within connective and mucosal tissues, where they differentiate and respond to various stimuli by releasing pro-inflammatory mediators, including histamine, growth factors, and proteases. This study demonstrated that primary human mast cells as well as the rat and human mast cell lines, RBL-2H3 and HMC-1, produce the heparan sulfate proteoglycan, perlecan, with a molecular mass of 640 kDa as well as smaller molecular mass species of 300 and 130 kDa. Utilizing domain-specific antibodies coupled with N-terminal sequencing, it was confirmed that both forms contained the C-terminal module of the protein core known as endorepellin, which were generated by mast cell-derived proteases. Domain-specific RT-PCR experiments demonstrated that transcripts corresponding to domains I and V, including endorepellin, were present; however, mRNA transcripts corresponding to regions of domain III were not present, suggesting that these cells were capable of producing spliced forms of the protein core. Fractions from mast cell cultures that were enriched for these fragments were shown to bind endothelial cells via the α(2)β(1) integrin and stimulate the migration of cells in "scratch assays," both activities of which were inhibited by incubation with either anti-endorepellin or anti-perlecan antibodies. This study shows for the first time that mast cells secrete and process the extracellular proteoglycan perlecan into fragments containing the endorepellin C-terminal region that regulate angiogenesis and matrix turnover, which are both key events in wound healing.
authors.affiliation: Graduate School of Biomedical Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia.
authors.forename: Moonsun
authors.initials: M
authors.lastname: Jung
authors.forename: Megan S
authors.initials: MS
authors.lastname: Lord
authors.forename: Bill
authors.initials: B
authors.lastname: Cheng
authors.forename: J Guy
authors.initials: JG
authors.lastname: Lyons
authors.forename: Hatem
authors.initials: H
authors.lastname: Alkhouri
authors.forename: J Margaret
authors.initials: JM
authors.lastname: Hughes
authors.forename: Simon J
authors.initials: SJ
authors.lastname: McCarthy
authors.forename: Renato V
authors.initials: RV
authors.lastname: Iozzo
authors.forename: John M
authors.initials: JM
authors.lastname: Whitelock
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002448:Cell Adhesion; D002460:Cell Line; D002465:Cell Movement; D003331:Coronary Vessels / Q000166:cytology; D042783:Endothelial Cells / Q000166:cytology / Q000378:metabolism; D006025:Glycosaminoglycans / Q000096:biosynthesis; D019812:Heparan Sulfate Proteoglycans / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D038982:Integrin alpha2beta1 / Q000378:metabolism; D008168:Lung / Q000166:cytology; D008407:Mast Cells / Q000166:cytology / Q000378:metabolism*; D008969:Molecular Sequence Data; D018919:Neovascularization, Physiologic; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011509:Proteoglycans / Q000096:biosynthesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D033921:Vesicular Transport Proteins / Q000096:biosynthesis; D014945:Wound Healing
chemical_list: D006025:Glycosaminoglycans; D019812:Heparan Sulfate Proteoglycans; D038982:Integrin alpha2beta1; D010446:Peptide Fragments; D020033:Protein Isoforms; D011509:Proteoglycans; D012333:RNA, Messenger; D033921:Vesicular Transport Proteins; C579274:endorepellin protein, rat; C075430:serglycin; C071927:perlecan