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<\/div>Stem cells are produced by bone marrow and can turn into different types of blood cells<\/p>\n
KATERYNA KON \/ SPL\/ Alamy<\/p>\n<\/div>\n<\/figcaption><\/figure>\n<\/p>\n
Human blood stem cells have been made in a laboratory for the first time, which could significantly improve how we treat certain types of cancer<\/a>.<\/p>\n The lab-grown cells have so far only been tested in mice, but when infused into the animals, the cells became functional bone marrow at similar levels to those seen after umbilical cord blood<\/a> cell transplants.<\/p>\n Treating cancers such as leukaemia and lymphoma via radiation and chemotherapy can destroy the blood-forming cells in bone marrow. A stem cell transplant means that new, healthy bone marrow and blood cells can grow. Umbilical cords are a particularly rich source of stem cells, but donations are limited and the transplant can be rejected by the body.<\/p>\n The new method would allow researchers to produce stem cells<\/a> from the actual patient, eliminating the supply issue and reducing the risk that their body would reject them.<\/p>\n First, human blood or skin cells were turned into so-called pluripotent stem cells through a process called reprogramming. \u201cThis involves temporarily turning on four genes, with the result that the patient cells revert to an early stage of development when they can become any cell in the body,\u201d says Andrew Elefanty<\/a> at the Murdoch Children\u2019s Research Institute in Melbourne.<\/p>\n <\/p>\n The second stage involved turning the pluripotent cells into blood stem cells. \u201cWe first make thousands of small floating balls of cells, a few hundred cells in each ball, and direct them to change from being stem cells to sequentially become blood vessels and then blood cells,\u201d says Elefanty. This process, called differentiation, takes about two weeks and makes millions of blood cells, he says.<\/p>\n These cells were then infused into mice that lacked an immune system<\/a> and became functional bone marrow in up to 50 per cent of cases. This means it made the same cells that carry oxygen and fight infections as healthy human bone marrow does, says Elefanty. \u201cIt is this unique ability to make all the blood cell types for a prolonged period of time that defines the cells as blood stem cells,\u201d he says.<\/p>\n Abbas Shafiee<\/a> at the University of Queensland in Brisbane says the work is a \u201cmagnificent breakthrough\u201d towards new therapies for blood cancers. \u201cIt has not been done before and it has a lot of potential for the future.\u201d But even once animal testing is complete, a lot of research in humans needs to be done before the approach can be used in clinics, he says.<\/p>\n