Angiogenesis And Accessibility

Dr. Folkman opened the meeting by sketching a list of 15 central questions and interesting problems in the field of angiogenesis research.  George Yancopoulos presented his discovery of a new family of angiogenesis stimulators, the angiopoietins.  He showed that angiopoietin-1 may work together with another angiogenic factor, VEGF to build normal new blood vessels in the embryo and possibly in wounds.  Furthermore, a related member of this family, angiopoietin-2 appears to be made by the endothelial cells which line the blood vessels coming into tumors.  Angiopoietin-2 appears to instruct new tumor vessels not to coat themselves with an outer layer of smooth muscle cells, as is the case for new vessels in wound.  This leaves tumor vessels with thin walls.  Dr. Yancopoulos made transgenic mice which over-produced angiopoietin-1 in their skin.  These mice produced extra vessels with large diameters, beneath the skin.  The mice had red Skin.  This proved that angiopoietin-1 is a new member of the family of angiogenic stimulators, but more importantly, the vessels did not leak blood or reveal microbleeding, as was the case with another angiogenic factor, VEGF