Artery smooth muscle- and vein smooth muscle-specific proteins and uses therefor

Patent Number: 7,163,808

The use of stem cells for stimulation of angiogenesis is of great interest to current researchers. The ability of stem cells to stimulate angiogenesis is dependent not only on differentiation of stem cells into endothelial cells, but also by virtue of stem cell secreted growth factors that promote localized tissue remodeling and proliferation of endogenous endothelial precursors.

The current patent covers the use of various surface molecules (Ephrins) as distinguishing features of arterial and venous smooth muscles cells. The importance of identifying, and therefore having the ability to isolate smooth muscle cells is that these cells contribute to stability and regulation of blood vessels. Through the use of the current invention it is possible to: a) assess whether an angiogenic stimulus is actually causing formation of new smooth muscle cells surrounding the new blood vessels; and b) to isolate smooth muscle cells and inject them with exogenous stem cells for formation of new blood vessels.

Previous attempts at angiogenesis therapy have been hampered by the fact that new blood vessels formed lacked appropriate smooth muscle cells and as a result were leaky. Indeed, the hyperangiogenesis associated with cancer results in formation of new blood vessels that area leaky due to poor content of smooth muscle cells. The fact that tumor cell associated endothelium is leaky is leveraged by drugs such as Abraxane, which selectively cross leaky endothelium and as a result preferentially accumulate within tumors and not normal tissue.

View this patent on the USPTO website.