Enhanced release of bone morphogenetic proteins from demineralized bone matrix by gamma irradiation

• Demineralized bone matrix (DBM) was gamma-irradiated for sterilization.
• Irradiated DBM had higher alkaline phosphatase and osteocalcin production.
• It was reasoned the more released bone morphogenetic proteins by irradiation.
• This result supports the application of radiation sterilization for bone implants.

Gamma irradiation is a useful method for sterilizing demineralized bone matrix (DBM), but its effect on the osteoinductivity of DBM is still controversial. In this study, the osteoinductive activity of gamma-irradiated DBM was examined using a mouse myoblastic cell line (C2C12). DBM was extracted from adult bovine bone and was irradiated at a dose of 25 kGy using a 60cobalt gamma-irradiator. Cell proliferation with DBM was not affected by gamma-irradiation, but alkaline phosphatase and osteocalcin productions were significantly increased in C2C12 cell groups treated with gamma-irradiated DBM. It was reasoned that bone morphogenetic proteins were more efficiently released from gamma-irradiated DBM than from the non-irradiated control. This result suggests the effectiveness of radiation sterilization of bone implants