Osteocel Plus is an allograft cellular bone matrix containing native mesenchymal stem cells (MSCs) which is intended to mimic the biologic performance of autograft without the morbidity associated with the autograft harvest. Mesenchymal stem cells, like those found in Osteocel Plus, are naturally occurring in the body and can differentiate into a variety of tissue types, depending on the local environment. Once implanted, MSCs can differentiate into osteoblasts, which produce new bone matrix. MSCs also naturally secrete bone-inducing growth factors that signal the patient's endogenous cells to migrate and participate in the bone formation process. Osteocel Plus is different from other orthobiologic products such as DBM and allograft cancellous bone because it contains living stem cells, which provide osteogenic potential. The cells include mesenchymal stem cells from an adult human donor; they are not from an embryonic source.