title: Thy-1 Regulates VEGF-Mediated Choroidal Endothelial Cell Activation and Migration: Implications in Neovascular Age-Related Macular Degeneration.
abstract: OBJECTIVE
  This study addresses the hypothesis that age-related stresses upregulate Thy-1 in choroidal endothelial cells (CECs) and contribute to CEC activation and migration, processes important in choroidal neovascularization (CNV).
  
  
  METHODS
  Measurements were made of Thy-1 protein (Western blot) in CECs and Thy-1 mRNA (real time quantitative PCR) in CECs treated with VEGF, CCL11, or PBS or in RPE/choroids from young or old donors or lasered or nonlasered mice. Immunolabeled Thy-1 in ocular sections was compared from young versus old human donor eyes or those with or without neovascular AMD or from lasered versus nonlasered mice. Choroidal endothelial cells transfected with Thy-1 or control siRNA or pretreated with Thy-1 blocking peptide or control were stimulated with VEGF or 7-ketocholesterol (7-KC). Choroidal endothelial cell migration, proliferation, cytoskeletal stress fibers, Rac1 activation, and phosphorylated VEGF receptor 2 (VEGFR2), integrin β3, and Src were measured. Statistics were performed using ANOVA.
  
  
  RESULTS
  Thy-1 was expressed in retinal ganglion cells and in vascular endothelial-cadherin-labeled choroid and localized to human or mouse laser-induced CNV lesions. Thy-1 protein and mRNA were significantly increased in CECs treated with VEGF or CCL11 and in RPE/choroids from aged versus young donor eyes or from lasered mice versus nonlasered controls. Knockdown or inhibition of Thy-1 in CECs significantly reduced VEGF-induced CEC migration and proliferation, stress fiber formation and VEGFR2, Src, integrin β3 and Rac1 activation, and 7-KC-induced Rac1 and Src activation.
  
  
  CONCLUSIONS
  Thy-1 in CECs regulates VEGF-induced CEC activation and migration and links extracellular 7-KC to intracellular signaling. Future studies elucidating Thy-1 mechanisms in neovascular AMD are warranted.
authors: The John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, United States.
authors: Haibo
authors: H
authors: Wang
authors: The John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, United States 2Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.
authors: Xiaokun
authors: X
authors: Han
authors: The John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, United States.
authors: Eric
authors: E
authors: Kunz
authors: The John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, United States.
authors: M Elizabeth
authors: ME
authors: Hartnett
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D015153:Blotting, Western; D002465:Cell Movement; D049109:Cell Proliferation; D002478:Cells, Cultured; D002829:Choroid / Q000098:blood supply / Q000378:metabolism*; D020256:Choroidal Neovascularization / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000378:metabolism / Q000473:pathology; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008268:Macular Degeneration / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D055213:Retinal Pigment Epithelium / Q000378:metabolism* / Q000473:pathology; D015398:Signal Transduction; D018800:Thy-1 Antigens / Q000096:biosynthesis / Q000235:genetics*; D014019:Tissue Donors; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*; D055815:Young Adult
chemical_list: D012333:RNA, Messenger; D018800:Thy-1 Antigens; D042461:Vascular Endothelial Growth Factor A