People with lupus have a markedly increased risk of developing osteoporosis. Clinical trials have shown that receiving a transplant of mesenchymal stem cells can greatly improve the condition of lupus patients, yet it has not been clear why this treatment strategy works so well.
Now, University of Pennsylvania researchers and colleagues have puzzled out a mechanism by which stem cell transplants may help preserve bone in an animal model of lupus. In a paper published in the journal Cell Metabolism, they show that the transplanted cells provide a source of a key protein called Fas, which improves the function of bone marrow stem cells through a multi-step, epigenetic effect. The work has implications for potential therapeutic strategies for lupus as well as other diseases for which stem cell transplants have shown promise.