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Monitoring Stem Cell Research 
inhibitory effect on alloimmune reactivity, the possibility exists that 
they could theoretically be derived from a donor irrespective of their 
HLA type and used to inhibit T-cell responses to transplantation 
antigens of an unrelated third party. In initial human clinical studies, 
the use human adult bone marrow-derived mesenchymal stem cells 
has been shown to successfully enable engraftment of subsequently 
infused allogeneic bone marrow in transplant recipients, reduce the 
risk of graft-versus-host disease, and reduce the need for 
concomitantly administered immunosuppression. Whether similar 
results v\hll be obtained when combining adult bone marrow-derived 
mesenchymal stem cells with solid organ allografts remains to be 
determined, and this is an area of active research for clinical 
transplant immunobiologists. Of broader relevance, if the results 
relating to long-term engraftment and survival of adult bone marrow- 
derived MSG are confirmed and extended in human clinical studies, 
they will have broad implications for the field of tissue and organ 
regeneration. 
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