Radiographic evaluation of healing potential of stem cell-loaded scaffold in experimental bone defect

Regeneration of critical size bone defects using tissue engineered constructs involving bone scaffolds and stem cells is being extensively evaluated. The main aim remains to develop an effective and affordable biomaterials in general and in veterinary medicine, in particular. The present study sought to explore the feasibility of using decellularized bovine (xenogenic) cancellous bone scaffold and allogenic mesenchymal stem cells (MSCs) for treating critical-size bone defects. The in vivo study was carried out in grey giant rabbits (n=48) equally divided in 4 groups as per the treatment protocol with left side critical size bone defect in radial diaphysis. The radiographic evaluation on day 30, revealed little radiopacity at defect site in Group I (self-repair without implant) and Group III (decellularized bovine bone scaffold, DBBG) while as in Group II (autologous implant) and Group IV (decellularized bone graft loaded with allogenic mesenchymal stem cells) larger area of radiopacity with external callus and bridging of defect was recorded. In Group I there was no apparent change at day 60th with unrepaired sections seen on radiograph but in Group II and Group IV complete union was seen with most extensive callus formation in Group IV and moderate amount of callus in Group III. Stem cell loaded bovine decellularized scaffold is an effective strategy to improve bone regeneration in critical size gap defects in rabbits.