Research On The Effects Of Human Umbilical Cord Mesenchymal Stem Cells In Wear Particle-induced Murine Calvarial Osteolysis

Objective:Aseptic loosening is a common late complication of artificial joint replacement.As the main inducement of aseptic loosening,wear particles could impair the functions of the cells around the prosthesis directly or indirectly.Studies indicated that the constant release of wear particles from the prosthesis stimulate the interaction between the periprosthetic cells,thus inducing periprosthetic chronic inflammation,reducing bone formation and increasing osteolysis,eventually leading to loosening of artificial joint prosthesis.Currently,the only clinical treatment for aseptic loosening is joint revision,but this operation is difficult and the long-term effect is controversial.As a result,further research on possible non-surgical intervention is necessary.As the main source of osteoblasts,mesenchymal stem cells(MSCs)play a vital role in the process of bone formation.Human umbilical cord mesenchymal stem cells(h UCMSCs),one kind of MSCs,have the advantages of easy extraction,low immunogenicity and suppressing the inflammatory response.The h UCMSCs have potential of osteogenetic differentiation and thus were applied in bone tissue engineering.Therefore,to investigate the effect of HUCMSCs on wear particle induced osteolysis,we established an animal model of wear particles-induced murine calvarial osteolysis.Methods:First,we verified characteristics of h UCMSCs from health pregnant women by the means of flow cytometry,as well as Co Cr Mo metal wear particles from patients with aseptic loosening by electron microscope and X-ray diffractometer.Then the h UCMSCs were used to treat animal models at different doses.Results:The results showed that repeated administration of h UCMSCs could significantly reduce osteolysis and decrease the number of local activated osteoclasts in the murine calvaria,and thus suppressing the expression level of TNF-α in the local calvarial periosteal tissues.Conclusion:Our results suggested that h UCMSCs inhibited wear particles-induced murine calvarial osteolysis by inhibiting the activation of local osteoclasts in the murine calvaria and the expression of inflammatory factors in periosteum tissue.This research provided a new insight and theoretical basis for the non-surgical prevention and treatment of aseptic loosening.