title: Regeneration of ovine articular cartilage defects by cell-free polymer-based implants.
abstract: The aim of our study was the evaluation of a cell-free cartilage implant that allows the recruitment of mesenchymal stem and progenitor cells by chemo-attractants and subsequent guidance of the progenitors to form cartilage repair tissue after microfracture. Chemotactic activity of human serum on human mesenchymal progenitors was tested in 96-well chemotaxis assays and chondrogenic differentiation was assessed by gene expression profiling after stimulating progenitors with hyaluronan in high-density cultures. Autologous serum and hyaluronan were combined with polyglycolic acid (PGA) scaffolds and were implanted into full-thickness articular cartilage defects of the sheep pre-treated with microfracture. Defects treated with microfracture served as controls. Human serum was a potent chemo-attractant and efficiently recruited mesenchymal progenitors. Chondrogenic differentiation of progenitors upon stimulation with hyaluronan was shown by the induction of typical chondrogenic marker genes like type II collagen and aggrecan. Three months after implantation of the cell-free implant, histological analysis documented the formation of a cartilaginous repair tissue. Controls treated with microfracture showed no formation of repair tissue. The cell-free cartilage implant consisting of autologous serum, hyaluronan and PGA utilizes the migration and differentiation potential of mesenchymal progenitors for cartilage regeneration and is well suited for the treatment of cartilage defects after microfracture.
authors: Department of Traumatology and Orthopaedic Surgery, University of Freiburg, Hugstetter Street 55, 79106 Freiburg, Germany.
authors: Christoph
authors: C
authors: Erggelet
authors: Katja
authors: K
authors: Neumann
authors: Michaela
authors: M
authors: Endres
authors: Kathrin
authors: K
authors: Haberstroh
authors: Michael
authors: M
authors: Sittinger
authors: Christian
authors: C
authors: Kaps
mesh_terms: D000818:Animals; D054544:Arthroplasty, Subchondral; D002358:Cartilage, Articular / Q000187:drug effects* / Q000293:injuries / Q000473:pathology* / Q000601:surgery; D002465:Cell Movement; D002474:Cell-Free System; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D006820:Hyaluronic Acid / Q000494:pharmacology; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects; D011108:Polymers / Q000737:chemistry* / Q000494:pharmacology*; D019736:Prostheses and Implants; D012038:Regeneration / Q000187:drug effects*; D044967:Serum; D012756:Sheep
chemical_list: D011108:Polymers; D006820:Hyaluronic Acid