2015 Volume No 30  pages 303-314
|  Title: The infrapatellar fat pad from diseased joints inhibits chondrogenesis of mesenchymal stem cells | 
| Authors: W Wei, R Rudjito, N Fahy, JAN Verhaar, S Clockaerts, YM Bastiaansen-Jenniskens, GJVM van Osch | 
|  Address: Department of Orthopaedics and Otorhinolaryngology, Ee1655, Erasmus MC University Medical Centre, Wytemaweg 80, 3015 CN, Rotterdam, The Netherlands | 
| E-mail: g.vanosch at erasmusmc.nl | 
|  Key Words: Cartilage repair, mesenchymal stem cells, infrapatellar fat pad, osteoarthritis, inflammation, obesity. | 
| Publication date: December 2nd 2015 | 
|  Abstract: Cartilage repair by bone marrow derived  mesenchymal stem cells (MSCs) can be influenced by inflammation in the knee.  Next to synovium, the infrapatellar fat pad (IPFP) has been described as a  source for inflammatory factors. Here, we investigated whether factors secreted  by the IPFP affect chondrogenesis of MSCs and whether this is influenced by  different joint pathologies or obesity. Furthermore, we examined the role of  IPFP resident macrophages. First, we made conditioned medium from IPFP obtained  from osteoarthritic joints, IPFP from traumatically injured joints during  anterior cruciate ligament reconstruction, and subcutaneous adipose tissue.  Additionally, we made conditioned medium of macrophages isolated from  osteoarthritic IPFP and of polarised monocytes from peripheral blood. We  evaluated the effect of different types of conditioned medium on MSC  chondrogenesis. Conditioned medium from IPFP decreased collagen 2 and aggrecan  gene expression as well as thionin and collagen type 2 staining. This  anti-chondrogenic effect was the same for conditioned medium from IPFP of  osteoarthritic and traumatically injured joints. Furthermore, IPFP from obese  (Body Mass Index >30) donors did not inhibit chondrogenesis more than that  of lean (Body Mass Index <25) donors. Finally, conditioned medium from  macrophages isolated from IPFP decreased the expression of hyaline cartilage  genes, as did peripheral blood monocytes stimulated with pro-inflammatory  cytokines. The IPFP and the resident pro-inflammatory macrophages could  therefore be targets for therapies to improve MSC-based cartilage repair. | 
| Article download: Pages 
                303-314 (PDF file) | 

 
     
     
     
    