Chondrogenic Progenitor Cells Isolated From The Fascia Of Skeletal Muscle

Background:Osteoarthritis(OA)is a common cause of chronic pain and even disability in the middle-aged and elderly people,especially in the hip and knee joints.The distinguish feature of pathological changes in the affected joint is articular cartilage degeneration and osteophyte formation.Due to the poor blood supply of the articular cartilage,its repair capacity is very limited.Although a variety of treatment regimens have been applied during the treatment of OA patients,there are no effective treatments but arthroplasty.Therefore,many researchers conducted in-depth research on the tissue engineering technology for repairing articular cartilage.However,the suitable seed cells are still the main problems restricting the application of tissue engineering in cartilage.Many experimental studies remain some limitations.Muscle derived cells in skeletal muscle have the ability to differentiate into cartilage in the culture of BMP-4 and TGF-?3.Skeletal muscle,for its wide source,easy access,relatively low immunogenicity,easier to control in vitro culture,can be an ideal seed cell source of fine conditions in the future.However,due to the complexity of skeletal muscle,including muscle fibers,fascia,Vascular tissue,nerve tissue and circulating blood vessels and so on,the original cell has not been identified.Objective:To verify the ability of cartilage differentiation of fascia-derived cells,the analysis,from the aspect of histological and cytological respectively,of skeletal muscle fascia tissue macrostructure,separation and purification and the distribution characteristics of cell surface markers were conducted.After culturing in cartilageforming medium containing BMP4 and TGF-?3 with L6 myoblasts at different proportions,the differentiation into cartilage cells of each group was analyzed in order to clarify the presence of cartilage differentiation-capable seed cells in skeletalderived cells.Observe the potential for chondrogenic differentiation of fascia derived cells(FDCs),in order to clarify the chondrogenic progenitor cells of cartilage in the cells derived from skeletal muscle.Methods:In the present study,using a rat model,we isolated cells from the fascia of skeletal muscle,termed as fascia derived cells(FDCs).The fascia then was cultured in chondrogenic medium(Cambrex)containing BMP4(500ng/ml);Samples were harvested on days 14.Alcian blue/Eosin and Safranin O stainings were used to identify chondrogenic differentiation.Cell markers were investigated by immunostaining using the antibodies for desmin,CD34,vimentin,vWF and a-SMA.Immunostaining was used to assay the potential of Chondrogenic in pellets with varying ratios of FDCs and L6 myoblasts.Results:Fascia harvested from skeletal muscle displayed chondrogenic differentiation and formed cartilaginous tissue when cultured for 14 days in chondrogenic medium.Cells isolated from fascia were negative for desmin(a myogenic marker),CD34,vWF(a endothelial marker)and a-SMA(pericyte marker),but a high percentage of the cells(>90%)expressed vimentin(a fibroblastic marker).Histological examination of fascia-derived cell pellets cultured in chondrogenic medium containing BMP4 revealed positive stainings for Alcian blue and Safranin O.Mixed FDC and L6 myoblast pellets showed chondrogenic potential decreased with increasing ratio of L6 myoblasts to FDCs.Conclusion:From the analysis of cell surface marker of fascia-derived cells(FDCs)in skeletal muscle,immunostaining,FDCs have the ability to differentiate into chondrocytes;After mixed culture with FDCs and L6 rat myoblasts at different proportions,the differences indicate that FDCs are cartilage-capable seed cells in skeletal-derived cells,whereas myoblasts do not possess cartilage-forming ability.