Mouse model of human immune system inadequate for stem cell studies
Known as "humanized" mice, the animals have been engineered to have a human, rather than a murine, immune system. Researchers have relied upon the animals for decades to study, among other things, the immune response to the transplantation of pancreatic islet cells for diabetes and skin grafts for burn victims. However, the Stanford researchers found that, unlike what would occur in a human patient, the humanized mice are unable to robustly reject the transplantation of genetically mismatched human stem cells. As a result, they can't be used to study the immunosuppressive drugs that patients will likely require after transplant. The researchers conclude that the humanized mouse model is not suitable for studying the human immune response to transplanted stem cells or cells derived from them. "In an ideal situation, these humanized mice would reject foreign stem cells just as a human patient would," said Joseph Wu, MD, PhD , director of Stanford's Ca