Injectable repair offull-thickness cartilage defects with basic fibroblast growth factor-modified bone marrowmesenchymal cells

Abstract

：Objective To testify thefeasibility of the basic fibroblast growth factor (bFGF)-modified bone marrow mesenchymalstem cells to repair full-thickness cartilage defects by injection.Methods The bone marrowstromal cells (BMSCs) were derived from bone nla.rYow of the rabbits and cultured invitro,and modified by bFGF.The Expression of the type Ⅱ collagen and aggrecan Was detected by immunohistochemistry and RT-PCR.Twenty-oneNew Zealand white rabbits were divided into three groups randomly.The cultured BMSCs mixedwith calcium alginate gel were used to fill the full-thickness hyaline cartilage defectscreated at the femoral condyle,and the de~cts repaired with gel or without treatmentserved as control groups.After 8 weeks,the reconstructed tissue Was evaluatedmacroscopically and microscopically.Histologic analysis and electron microscopic detectionwere also performed to observe the structure of repair tissue.Results The populationdoubling time(PDrr)of BMSCs was about 33.8 h.The exprezsion of the type Ⅱ collagen and aggrecan was detected after bFGF application.Thereconstructed tissue with BMSCs was similar with the microstructure of hyalinecartilage,and contained ulore ceils and thick extracellular matrix than other groups.TypeⅡ collagen wasdetected within the matrix by immunohistochemical staining.Plenty of collagen fibersaround cells could be seen under the transmission electron microscopy.Only partial softconnective tissue filled the bottom of the defects in other two control groups.ConclusionThe compound of bFGF-modified BMSCs with injectable calcium alginate gel is applicable forfull-thickness cartilage defects. Key words: Cartilage; Defect; Basic fibroblast growth factor; Bonemarrow mesenchymal stem cells