Research On The Regenerative Effect Of Human Umbilical Cord Mesenchymal Stem Cells And Platelet-rich Plasma On Healing In Chondral Defects

Background:Articular cartilage’s basic framework is composed of collagen fibers, it’s surface belongs to hyaline cartilage and is relatively smooth, pale blue, luster, no innervation and blood vessel.Once the articular cartilage injuries, its repair is unlikely.The regeneration method is cartilage transplantation, but the source of cartilage is limited. For autologous transplantation bring patients with secondary trauma and increase patients’ pain and heterotransplantation has strong graft rejection problems.This technology is not yet mature and its application is limited.Bone marrow stromal stem cells and h UCMSCs have many similar functions.HUCMSCs have stronger ability of amplification and low immunogenicity on osteogenesis and tissue repair, and its colony growth potential and osteogenesis time are earlier than other sources.And induced experiment in vitro has confirmed that h UCMSCs have osteogenesis effect and can repair bone injury. Some scholars think that h UCMSCs can replace bone marrow stromal stem cells in the research application. PRP co-culture with BMSCs found that BMSCs have the tendency of differentiating into cartilage cells. PRP is the autologous whole blood platelet concentration and contains a large number of growth factors and proteins.These growth factors constitute a complex regulation network through many ways, versatility and collaboration.These growth factors can promote bone repair through synergistic effect.Objective:The experiment was designed to confirm that h UMSCs and PRP can repair cartilage damage and observe their combination effect.Methods: Forty healthy New Zealand white rabbits were selected to establish models of cartilage defects, and then randomly divided into normal saline group, PRP group, h UCMSCs group and the combination group. PRP was prepared by using double centrifugations.Prepare passage 3 h UCMSCs. After modeling, intra-articular injection of normal saline(0.5 ml),platelet-rich plasma(0.5 ml),1×107h UCMSCs(0.5 ml), platelet-rich plasma(12.5%) with h UCMSCs(1×107)totally0.5 ml in corresponding groups respectively. After 12 weeks of modeling,the injured cartilage were evaluated including gross morphology observation;hematoxylin-eosin staining was used to observe cartilage repair under light microscope;The O’Driscoll histologic standard was used for histologic grading.Results and Conclusion:12 weeks after repairing,the gross morphology observation, hematoxylin eosin staining and O ’Driscoll histological grading results showed that h UCMSCs group, PRP group, PRP with h UCMSCs group were better than saline group, with significant difference(P<0.05).The repair effect of PRP group, PRP with h UCMSCs group were better than that of h UCMSCs group, with significant difference(P<0.05). Results showed that h UCMSCs and PRP can promote the repair of cartilage damage and PRP, PRP with h UCMSCs are better than h UCMSCs alone.