Polypeptide having an activity to support proliferation or survival of hematopoietic stem or progenitor cells

Patent Number: 7,439,332

This patent covers a specific nucleic acid sequence and expressed protein thereof, for the stimulation of erythropoiesis. 

The inventors identified the protein through establishing stromal cell lines from the AGM (Aorta-Gonad-Mesonephros) region of a fetal mouse and screening them to see which ones support hematopoiesis, and which type of hematopoietic propensity (eg were they stimulating more erythropoiesis, or more lymphopoiesis, or more granulopoiesis?  They found a stromal cell line that stimulated more erythropoiesis, did genetic analysis, and found certain genes that were upregulated.  They tied the gene to function, filed the patent, and it got issued.

This patent is worth reading because of the neat way that they found the patentable product.  There are other agents that stimulate hematopoiesis, for example US patent #5,968,513 covers the use of human chorionic gonadotrophin (hCG) for stimulation of hematopoiesis;  US patent # 6,103,701 covers acyl deoxyribonucleosides for stimulation of hematopoiesis; US patent #6,348,444 covers growth hormone for stimulation of hematopoietic stem cells; and US patent # 6,713,065 covers the use of hedgehog proteins for the same thing.  Unfortunately, it is difficult to compare efficacy of all these agents side by side since they used different experimental protocols of assessing potency of hematopoietic stimulation.  Additionally, various assays detect various stages of "stemness".

View this patent on the USPTO website.