Novel enzymatic processing of perlecan by mast cells: a potential role in angiogenesis

Download files
Access & Terms of Use
open access
Copyright: Jung, Moonsun
Altmetric
Abstract
Mast cells are multifunctional secretory cells that are involved in allergy and autoimmune diseases and predominantly were found in blood vessels near connective tissues of the skin and mucosa. These cells respond to various stimuli by releasing pro-inflammatory mediators including histamine, growth factors, and proteases. The proximity of mast cells to blood vessels together with the mediators released by these cells upon activation suggests a role of mast cell in angiogenesis. The aim of the thesis was to characterise the structure of proteoglycans (PGs) produced by model mast cells and determine whether the proteases released by activated mast cells were capable of processing extracellular matrix components, including heparan sulfate (HS) PGs, into fragments that modulate angiogenesis. Rat and human model mast cell lines, RBL-2H3 and HMC-1, were found to produce chondroitin sulfate (CS), HS and heparin. Both cell lines were found to produce and secrete serglycin, which was detected as two protein cores (11 and 13 kDa) decorated with both CS and HS. Novel finding in this thesis is that the model mast cells are capable of producing and secreting perlecan decorated with HS and CS, which was detected as both full length material (600 kDa) and fragments of 130 and 300 kDa. This suggested that perlecan may be processed by mast cell proteases. Alignment of the cleavage specificities of mast cell proteases with the N-terminal amino acid sequences of perlecan fragments showed that cathepsin S and MMPs-3 and -13 present in mast cells are potential candidate proteases that process perlecan. Releasate from activated HMC-1 cells was found to promote endothelial cell proliferation and migration to the same extent as FGF2 in an in vitro ‘scratch’ assay. Addition of anti-FGF2, anti-VEGF165 or anti-perlecan antibodies including those specific for domains I, III and V of the protein core, significantly inhibited endothelial cell migration in the presence of activated HMC-1 cell releasate. This is another novel finding of the work presented in this thesis and suggests that mast cells release growth factors and proteases to stimulate ECM remodelling, including perlecan fragmentation and the release of bound growth factors, for endothelial cell proliferation and migration, which are essential for in vivo in the context of angiogenesis in wound healing.
Persistent link to this record
Link to Publisher Version
Link to Open Access Version
Additional Link
Author(s)
Jung, Moonsun
Supervisor(s)
Whitelock, John
Lord, Megan
Creator(s)
Editor(s)
Translator(s)
Curator(s)
Designer(s)
Arranger(s)
Composer(s)
Recordist(s)
Conference Proceedings Editor(s)
Other Contributor(s)
Corporate/Industry Contributor(s)
Publication Year
2010
Resource Type
Thesis
Degree Type
PhD Doctorate
UNSW Faculty
Files
download whole.pdf 1.79 MB Adobe Portable Document Format
Related dataset(s)