A number of competing lines of research aim at producing large volumes of blood to order, with an eye to eventually eliminating the need for blood donors and all of the shortcomings inherent in donated blood - the need for screening and other expenses in the donation process, the short shelf-life of blood outside the body, and so forth. Firstly there is the approach of creating synthetic blood substitutes, which will be most likely restricted to short-term use in trauma cases for the near future as the intent is to provide the critical function of oxygen transport and little else. Then there are the varied efforts to grow blood from stem cells, some of which are coming closer to clinical trials, an initial step on the way to commercialization. A decade from now blood factories will be established in much the same way as skin factories are a going concern at present: there will likely be some mix of generic blood types produced in bulk from known lineages alongside the ability to create blood to order from a specific patient's cells.
A few years back the researchers involved in the work quoted below estimated that blood derived from stem cells would be in trials by now. They are presently looking at starting small trials in 2016 at the earliest, which perhaps illustrates why scientists are usually cautious about putting timelines on the table, especially in an environment of heavy government regulation, where new delays and new expenses are ever on the menu.
The consortium will be using pluripotent stem cells, which are able to form any other cell in the body. The team will guide these cells in the lab to multiply and become fresh red blood cells for use in humans, with the hope of making the process scalable for manufacture on a commercial scale. The team hopes to start the first-in-man trial by late 2016.
Blood transfusions play a critical role in current clinical practice, with over 90m red blood cell transfusions taking place each year worldwide. Transfusions are currently made possible by blood donation programmes, but supplies are insufficient in many countries globally. Blood donations also bring a range of challenges with them, including the risk of transmitting infections, the potential for incompatibility with the recipient's immune system and the possibility of iron overload. The use of cultured red blood cells in transfusions could avoid these risks and provide fresh, younger cells that may have a clinical advantage by surviving longer and performing better.
Professor Marc Turner, Principal Investigator, said: "Producing a cellular therapy which is of the scale, quality and safety required for human clinical trials is a very significant challenge, but if we can achieve success with this first-in-man clinical study it will be an important step forward to enable populations all over the world to benefit from blood transfusions. These developments will also provide information of value to other researchers working on the development of cellular therapies."
Prof Turner has devised a technique to culture red blood cells from induced pluripotent stem (iPS) cells - cells that have been taken from humans and 'rewound' into stem cells. Biochemical conditions similar to those in the human body are then recreated to induce the iPS cells to mature into red blood cells - of the rare universal blood type O.
There are plans in place for the trial to be concluded by late 2016 or early 2017, he said. It will most likely involve the treatment of three patients with Thalassaemia, a blood disorder requiring regular transfusions. The behaviour of the manufactured blood cells will then be monitored.
This sort of pace of development will likely be beaten to the end goal of commercial blood manufacture by less constrained and more ambitious commercial development in East Asia, I'd imagine. That has been the pattern so far in the development of applied stem cell technologies, at least.