Combining Bone Collagen Matrix with hUC-MSCs for Application to Alveolar Process Cleft in a Rabbit Model

Background: Most materials used clinically for filling severe bone defects either cannot induce bone re-generation or exhibit low bone conversion, therefore, their therapeutic effects are limited. Human umbilical cord mesenchymal stem cells (hUC-MSCs) exhibit good osteoinduction. However, the mechanism by which combining a heterogeneous bone collagen matrix with hUC-MSCs to repair the bone defects of alveolar process clefts remains unclear.Methods: A rabbit alveolar process cleft model was established by removing the bone tissue from the left maxillary bone. 48 young Japanese white rabbits (JWRs) were divided into normal, control, material and MSCs groups. An equal volume of a bone collagen matrix alone or combined with hUC-MSCs was implanted in the defect. X-ray, micro-focus computed tomography (micro-CT), blood analysis, histochemical staining and TUNEL were used to detect the newly formed bone in the defect area at 3 and 6 months after the surgery. Results: The bone formation rate obtained from the skull tissue in MSCs group was significantly higher than that in control group at 3 months (PPPPConclusions: Combining bone collagen matrix with hUC-MSCs promoted the new bone regeneration in the rabbit alveolar process cleft model through promoting osteoblasts formations and chondrocyte growth, and inducing type 1 collagen formation and BMP-2 generation.