From Scientific American, a look at progress towards diabetes therapies in the form of regenerative medicine for the pancreas: "In newly diabetic mice, the results were spectacular. After two weeks of treatment, the beta-cell mass had tripled, the insulin content had increased eightfold, and the blood glucose concentration had fallen to normal levels. It did not go so well in mice with long-standing diabetes: their glucose levels fell substantially, yet they needed some immunosuppressive medication. ... Even a partial regeneration in patients would at least get around the shortage of donor tissue and would probably require less immunotherapy; native cells would need defense from autoimmunity alone, not from that and organ rejection combined."