title: Phospholipase C-delta extends intercellular signalling range and responses to injury-released growth factors in non-excitable cells.
abstract: OBJECTIVE
  Intercellular communication in non-excitable cells is restricted to a limited range close to the signal source. Here, we have examined whether modification of the intracellular microenvironment could prolong the spatial proposition of signal generation and could increase cell proliferation.
  
  
  METHODS
  Mathematical models and experimental studies of endothelial repair after controlled mechanical injury were used. The models predict the diffusion range of injury-released growth factors and identify important parameters involved in a signalling regenerative mode. Transfected human umbilical vein endothelial cells (HUVECs) were used to validate model results, by examining intercellular calcium signalling range, cell proliferation and wound healing rate.
  
  
  RESULTS
  The models predict that growth factors have a limited capacity of extracellular diffusion and that intercellular signals are specially sensitive to cell phospholipase C-delta (PLCdelta) levels. As basal PLCdelta levels are increased by transfection, a significantly increased intercellular calcium range, enhanced cell proliferation, and faster wound healing rate were observed.
  
  
  CONCLUSIONS
  Our in silico and in vitro studies demonstrated that non-excitable endothelial cells respond to stimuli in a complex manner, in which intercellular communication is controlled by physicochemical properties of the stimulus and by the cell microenvironment. Such findings may have profound implications for our understanding of the tight nature of autocrine cell growth control, compensation to stress states and response to altered microenvironment, under pathological conditions.
authors.affiliation: Harvard-MIT Division of Health Science and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. liyumi@mit.edu
authors.forename: L Y
authors.initials: LY
authors.lastname: Mi
authors.forename: D S
authors.initials: DS
authors.lastname: Ettenson
authors.forename: E R
authors.initials: ER
authors.lastname: Edelman
mesh_terms: D002118:Calcium / Q000502:physiology; D002450:Cell Communication / Q000502:physiology; D004730:Endothelium, Vascular / Q000166:cytology / Q000502:physiology*; D005346:Fibroblast Growth Factors / Q000378:metabolism; D006133:Growth Substances / Q000378:metabolism*; D006801:Humans; D008954:Models, Biological; D054799:Phospholipase C beta / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D014471:Umbilical Veins; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D014947:Wounds and Injuries / Q000503:physiopathology*
chemical_list: D006133:Growth Substances; D042461:Vascular Endothelial Growth Factor A; D005346:Fibroblast Growth Factors; D054799:Phospholipase C beta; D002118:Calcium