Abstract
Purpose: :
Lumican, a major Keratan sulfate proteoglycan in corneal stroma, plays an important role in corneal wound healing. Human telomerase immortalized corneal epithelial cells (HTCE) cells were used to examine the cellular mechanism by which lumican modulates wound healing.
Methods: :
Recombinant GST-lumican (glutathione S-tranferase-lumican fusion protein) was isolated from E. coli transfected with pGEX-2T-lum plasmid, and subsequently purified using glutathione-Sepharose affinity column. Closure of scratch wound with confluent HTCE cultures was used to examine the rate of wound healing in the presence or absence of recombinant GST-lumican, in vitro. Immune fluorescence staining and western blot analysis with anti-Ki67, phospho-ERK1/2 and phospho-p38MAPK were performed to determine the effects of lumican on cell proliferation and signaling pathways on wound healing.
Results: :
GST-lumican promoted wound closure of an in vitro wound model. GST-lumican stimulated cell proliferation as shown by a marked increase of Ki67 positive cells at the edge of scratch and away from wound site than in comparison to that of control groups (without GST-lum and GST only treatments). Activation of ERK via phosphorylation was observed in 10 min of adding GST-lumican, phospho-p38MAPK was not detected within 1 hr after wounding in the presence or absence of GST-lumican.
Conclusions: :
These findings indicate that GST-lumican stimulates cell migration and proliferation during wound healing in vitro. The lumican effects on wound healing might be mediated via the activation of ERK 1/2 signaling pathways.
Keywords: wound healing • extracellular matrix • cornea: epithelium