There are a number of different lines of research focused on developing artificial blood or culturing blood to order from stem cells: "Clinical trials using blood created from adult stem cells are set to begin within the next two or three years, raising the prospect it could soon become routinely used where real blood is unavailable. Scientists are also developing alternative bloodlike substances which could be injected into the body as a 'stopgap' until an actual blood transfusion could be performed. ... modern doctors have minimised the risk of patients receiving infections such as Hepatitis A and C during transmission [but] blood produced from stem cells would avoid these risks and could be manufactured as type 'O-negative', which is produced by just 7 per cent of the population but is suitable for use in into up to 98 per cent of patients. ... It could also be used in certain hospital situations, for example in elective surgery, and save hundreds of thousands of lives in parts of the world where blood banks are not available. [Researchers have] developed a method of taking adult stem cells from bone marrow and growing them in the laboratory to produce cells which look and act almost identically to red blood cells. Once their technique is fine-tuned the team may consider using stem cells taken from embryos, or reprogrammed skin cells, instead of adult cells because although the end product does not mimic red blood as closely, they can be grown in much greater quantities in the lab. ... A more radical solution, which [researchers] say could be perfected within five to 10 years, is to develop a completely artificial alternative to blood which performs the same key functions and would be safe to use in patients of every blood type. This could involve packing haemoglobin - which carries oxygen around the body - into a synthetic cell-like structure, or using a chemical to hold the haemoglobin together so that it can be injected without the need for red blood cells."