Blood donation will be a thing of the past not so many years from now. Building blood to order is one of the fields of research and development in which entirely artificial alternatives might beat tissue engineering to the broader marketplace. On the one hand several well-funded initiatives presently aim to mass-produce particles that behave like red blood cells - and that might even perform some tasks more effectively than the real thing. On the other hand, tissue engineers are working on reliable methodologies to generate large quantities of blood from stem cells. The most advanced of these efforts have made it to the trial stage.
An example of the second approach can be found over at Singularity Hub:
Two years ago, DARPA awarded a $1.95 million grant to a Cleveland company called Arteriocyte, which was developing technology that could quickly transform stem cells into red blood cells. The idea was to develop a system that could produce an almost limitless amount of universal donor blood (O-negative) in remote areas. And earlier this month, Arteriocyte submitted samples of their artificially produced blood to the Food and Drug Administration (FDA), seeking approval before making the technology available to both the civilian and military sectors.
Hematopoietic cells isolated from umbilical cord blood are cultured in an environment that provides them with all the nutrients and molecular signals they need to develop into red blood cells. Currently, it takes about 3 days to generate up to 20 units of transfusion-ready blood from a single unit of umbilical cord blood.
It's a good example of how even early stage products of the growing regenerative medicine industry have the potential to produce large infrastructure changes - reducing cost and improving quality along the way. Looking at the other side of the aisle, an example of fully artificial red blood can be found back in the Fight Aging! archives:
Samir Mitragotri of the University of California and his team got their inspiration from the way real red blood cells acquire their final shape in the body. They start out as spherical cells which then collapse into mature red blood cells following exposure to various substances. Similarly, Mitragotri's team found that if they added small balls made of a polymer called PLGA to a particular solvent, the spheres would collapse into a biconcave shape.
The researchers coated these 7-micrometre across, tyre-shaped particles, in a layer of protein. When they dissolved away the polymer core, a soft biodegradable protein shell was left behind with the same mechanical properties as red blood cells.