Immunological study of allogeneic mesenchymal stem cells during bone formation.

Autologous mesenchymal stem cells (MSCs) are limited in their clinical application because tissue-engineered bone cannot be pre-fabricated. Allogeneic MSCs are readily available but carry the risk of transplant rejection. It is not yet clear whether allogeneic MSCs can induce a rejection response during bone formation. In this study, two strains of genetically unmatched mini-pigs were used as experimental animals to study the immunological changes in MSCs in vitro and in vivo when generating bone. Mini-pig MSCs showed low immunogenicity during osteogenesis both in vitro and in vivo, indicating that allogeneic MSCs had little or no immunogenicity in osteosis. In conclusion, allogeneic MSCs are an important source of seed cells for the tissue engineering of bone. This favours the clinical application of pre-constructed tissue-engineered bone.