(From PhysOrg.com). A growing breadth of approaches are emerging within the field of tissue engineering. Scientists "have developed a new technique which uses electricity to engineer human tissue. They now believe it may have the potential to engineer bespoke bone marrow. ... The technique, which uses electric fields to build up layers of cells to form a tissue, is being used to create Hematons - aggregates of blood producing cells essential in the function of healthy bone marrow. ... If we can perfect this technique then it may one day be possible to create artificial bone marrow outside the body and produce any given blood type ... By varying the voltage and using different electrode shapes, cells can be positioned and stacked on top of each other in any pattern. Different electric fields can also be used to attract different types of cells. Most importantly, cells can be kept alive and active."