Transplantation of Culture-Expanded Bone Marrow Mesenchymal Cells and Type I Collagen Gel-Xenograft Complex / 대한정형외과연구학회지

ABSTRACT

Bone marrow contains mesenchymal stem cells capable of differentiating into osteoblastic lineage. To test the ability of purified bone marrow mesenchymal cell loaded onto xenograft with type I collagen gel to heal bone defect, mesenchymal stem cells were isolated from bone marrow of Lewis rat, and culture-expanded. Northern blot hybridization revealed that osteocalcin and osteopontin mRNA expression persisted for 8 weeks of in-vitro culture. When the bone marrow mesenchymal cells became 80-90% confluent in 2-3 weeks, they were loaded onto chips of xenograft (Lubboc(R) with type I collagen gel. The cell-gel-xenograft composite was transplanted subcutaneously into the dorsum of nude mice. It was also transplanted into tibial diaphyseal defect made in syngeneic Lewis rats, and compared with the control group where only the xenograft was planted. There was no ectopic bone formation at the dorsum of nude mice around the transplanted cell-gel-xenograft complex. In the long bone defect model, the cell-gel-xenograft group induced fibrosis around it and the bone healing was inferior to the control group. Type I collagen gel is not a suitable carrier of bone marrow mesenchymal cells to heal the long bone defect.