Red blood cell blood circulation for about 100 to 120 days (and 80 to 90 days in a full term infant). At the end of their lifespan, they are removed from circulation. In many chronic diseases, the lifespan of the red blood cells is reduced. Erythropoiesis is the process by which new red blood cells are produced; it lasts about 7 days. Through this process red blood cells are continuously produced in the red bone marrow of large bones. (In the embryo, the liver is the main site of red blood cell production.) The production can be stimulated by the hormone erythropoietin (EPO),
Generative tissue becoming a living tissue. To date, the types of gTissue created can be characterized as variants of soft connective tissues including dermis, tendon, ligament, and fascia. Initially the cell-free ECM biomaterial is implanted and progressively adopted by the host. Immediately upon surgical implantation, the porous material becomes soaked in blood. This seeds the material with a population of circulating stem cells, and growth factors to support gTissue development. As generation progresses, the growth factors, cytokines, and fibrin provisional matrix signals host cells to repopulate the matrix. To support the metabolic activity of these cells, a vascular network is simultaneously created