title: Establishment of human retinal microvascular endothelial cells with extended life-span.
abstract: OBJECTIVE
  To generate and characterize a telomerase-immortalized human retinal microvascular endothelial cell (HREC) line. This cell line may be utilized as an in vitro model to study the molecular basis of several diseases of the human retina.
  
  
  METHODS
  Primary retinal neuronal cells were isolated and transfected with plasmid encoding full-length human telomerase reverse transcriptase (hTERT). Transfected cells were selected and characterized to determine telomerase activity, karyotype, proliferative capacity and functionality.
  
  
  RESULTS
  HREC-hTERT cells appear morphologically similar to primary endothelial cells and have an extended in vitro life-span. HREC-hTERT cells express the progenitor/stem cell marker nestin. They have active telomerase and a high proliferative capacity. These cells also maintain a diploid karyotype. The HREC-hTERT cells showed high colony-formation capacity and plating efficiency compared to the primary cells. These cells are capable of differentiation into neuronal and glial cell phenotypes and the differentiated cells express the astrocyte marker glial fibrillary acidic protein (GFAP) and the neuronal marker microtubule-associated protein-2 (MAP2), respectively.
  
  
  CONCLUSIONS
  The in vitro life-span of human retinal neuronal endothelial cells can be extended by ectopic expression of hTERT without altering the genetic stability and functionality of these cells. These cells will be a valuable tool to further our understanding on the role of HRECs in the human blood-retinal-barrier and in angiogenesis and neovascularization.
authors.affiliation: Professor and Dean, UNT Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, Texas 76107, U.S.A. Jamboor.vishwanatha@unthsc.edu.
authors.forename: Meghana V
authors.initials: MV
authors.lastname: Kashyap
authors.forename: Amalendu P
authors.initials: AP
authors.lastname: Ranjan
authors.forename: Jwalitha
authors.initials: J
authors.lastname: Shankardas
authors.forename: Jamboor K
authors.initials: JK
authors.lastname: Vishwanatha
mesh_terms: D018929:Cell Culture Techniques; D002454:Cell Differentiation; D049109:Cell Proliferation; D002469:Cell Separation; D048430:Cell Shape; D002478:Cells, Cultured; D016922:Cellular Senescence; D042783:Endothelial Cells / Q000502:physiology*; D004730:Endothelium, Vascular / Q000166:cytology*; D006801:Humans; D059785:Karyotype; D055806:Microvessels / Q000166:cytology; D010641:Phenotype; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D012171:Retinal Vessels / Q000166:cytology; D019098:Telomerase / Q000378:metabolism; D014841:von Willebrand Factor / Q000378:metabolism
chemical_list: D019408:Platelet Endothelial Cell Adhesion Molecule-1; C029417:Von Willebrand antigen; D014841:von Willebrand Factor; C509186:TERT protein, human; D019098:Telomerase
keywords: Retina; extended life-span; neuronal endothelial cells; telomerase