**Please mention the Journal of Clinical Investigation as the source of these articles**

Find below two highlighted articles and the full Table of Contents for the December 2, 2002 issue

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Restoration of Faulty Blood Vessel Architecture by Angiopoietin-1

Angiogenesis (the growth of new blood vessels) requires complex signaling between multiple cell types, and abnormalities in these pathways results in faulty vessels. During normal vessel formation endothelial cells that comprise the blood vessel communicate, through a number of secreted agents called growth factors, with a family of cells known as mural cells. Endothelial cells secrete the growth factor PDGF B that is bound to mural cells by the PDGF-b receptor. Murals cells are then recruited to the new vessel where upon direct interaction with endothelial cells they secrete angiopoietin-1 (Ang1). Multiple roles in vessel maturation have been designated to Ang1 and they include sprouting, survival and stability of the new vessel. However, the exact nature of its involvement is unclear. The critical interactions between endothelial cells and mural cells facilitate the growth and maturation of new blood vessels. In diseases such as diabetic retinopathy, mural cells are absent from the vessel maturation process, which results in abnormal vessels growing on top of the retina, which can lead to blindness. The complex mechanisms by which mural cells regulate the activity of endothelial cells is also unclear. One way to investigate this relationship would be to develop an experimental system in which mural cells and endothelial cells are separated, yet new blood vessels still develop. As this development usually happens in the early embryo, it has been a difficult experimental system to manipulate. In the December 2 issue of the Journal of Clinical Investigation, Akiyoshi Uemura a
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Contact: Brooke Grindlinger, PhD
science_editor@the-jci.org
212-342-9006
Journal of Clinical Investigation
3-Dec-2002