Intervertebral disc regeneration in an ex vivo culture system using mesenchymal stem cells and platelet-rich plasma Wei-Hong Chen a, b,1 , Hen-Yu Liu c,1 , Wen-Cheng Lo d,1 , Shinn-Chih Wu e , Chau-Hwa Chi f , Hsueh-Yuan Chang g , Shih-Hsiang Hsiao e , Chih-Hsiung Wu h , Wen-Ta Chiu i , Bao-Ji Chen e , Win-Ping Deng a, b, j, * a Stem Cell Research Center, Taipei Medical University, Taipei, Taiwan, ROC b Graduate Institute of Biomedical Materials and Engineering, Taipei Medical University, Taipei, Taiwan, ROC c Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan, ROC d Department of Neurosurgery, Taipei Medical University, Taipei, Taiwan, ROC e Department of Animal Science and Technology, National Taiwan University, Taipei, Taiwan, ROC f School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan, ROC g School of Pharmacy, College of Medicine, National Taiwan University, Taiwan, ROC h Division of General Surgery, Department of Surgery, Taipei Medical University, Taiwan, ROC i Department of Neurosurgery, Taipei Medical University–Wan Fang Hospital, Taipei, Taiwan, ROC j Cancer Center, Taipei Medical University Hospital, Taipei, Taiwan, ROC article info Article history: Received 15 April 2009 Accepted 8 July 2009 Available online 30 July 2009 Keywords: Intervertebral disc Mesenchymal stem cell Platelet-rich plasma Nucleus pulposus Regeneration abstract An ex vivo degenerative intervertebral disc (IVD) organ culture system was established for the screening of disc regeneration agents. Its application was demonstrated by a stem cell and growth factor-based therapeutic approach for the amelioration of IVD. An ex vivo culture system using chymopapain to partially digest nucleus proposus tissue was established to mimic human IVD degeneration. This system was then used for the evaluation of different therapeutic regimens including: mesenchymal stem cell derived from eGFP-transgenic porcine (MSC-GFP), platelet-rich plasma (PRP) and MSC-GFP/PRP combined treatment, and confirmed in in vivo animal model. Chondrogenic-specific gene products including Col II and aggrecan were found upregulated and chondrogenic matrix deposition increased, as evident by sustained fluorescent signals over 4 weeks, in the MSC-GFP implanted group. Previously, we demonstrated in vitro stage-specific chondrogenesis of MSC by chondrocytic commitment. These same molecules upregulated for chondrogenesis were also observed in MSC-GFP group. PRP that has been shown to promote nucleus pulposus (NP) regeneration also resulted in significant increased levels of mRNA involved in chondrogenesis and matrices accumulation. The ex vivo IVD regeneration results were repeated and supported by in vivo porcine degenerative system. Moreover, the disc height index (DHI) was significantly increased in both in vivo MSC-GFP and PRP regeneration groups. Unexpectedly, the MSC-GFP/PRP combined therapy demonstrated an inclination towards osteogenesis in ex vivo system. The ex vivo degenerative IVD culture system described in this study could serve as an alternative and more accessible model over large animal model. This system also provides a high-throughput platform for screening therapeutic agents for IVD regeneration. Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction Low back pain (LBP) induced by intervertebral disc (IVD) degeneration has excruciated approximately 80% aging population and caused a significant socio-economic problem [1]. The tissue degeneration often originated from the high degradation of proteoglycan composites in nucleus pulposus (NP), and the extra- cellular matrix (ECM) was subsequently altered, representing the major pathogenic characterization of IVD degeneration [2]. In the multiple and complex process of IVD degeneration, the breakdown of cross-link in collagen fibers and disorganizations of proteoglycan composites will result in structural deformation and dehydration in discs, respectively [3]. Hence, therapeutic strategies for IVD degeneration have become emergent to be further developed. The * Corresponding author. Institute of Biomedical Materials and Engineering, Taipei Medical University, 250 Wu-Hsing Street, Taipei 110, Taiwan, ROC. Tel.: þ886 2 2739 0863; fax: þ886 2 2739 5584. E-mail address: wpdeng@ms41.hinet.net (W.-P. Deng). 1 These authors contributed equally to this work. Contents lists available at ScienceDirect Biomaterials journal homepage: www.elsevier.com/locate/biomaterials 0142-9612/$ – see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.biomaterials.2009.07.019 Biomaterials 30 (2009) 5523–5533