Intra-articular injection of micronized dehydrated human amnion/chorion membrane attenuates osteoarthritis development

Introduction: Micronized dehydrated human amnion/chorion membrane (mu-dHACM) is derived from donated human placentae and has anti-inflammatory, low immunogenic and anti-fibrotic properties. The objective of this study was to quantitatively assess the efficacy of mu-dHACM as a disease modifying intervention in a rat model of osteoarthritis (OA). It was hypothesized that intra-articular injection of mu-dHACM would attenuate OA progression. Methods: Lewis rats underwent medial meniscal transection (MMT) surgery to induce OA. Twenty four hours post-surgery, mu-dHACM or saline was injected intra-articularly into the rat joint. Na ve rats also received mu-dHACM injections. Microstructural changes in the tibial articular cartilage were assessed using equilibrium partitioning of an ionic contrast agent (EPIC-mu CT) at 21 days post-surgery. The joint was also evaluated histologically and synovial fluid was analyzed for inflammatory markers at 3 and 21 days post-surgery. Results: There was no measured baseline effect of mu-dHACM on cartilage in na ve animals. Histological staining of treated joints showed presence of mu-dHACM in the synovium along with local hypercellularity at 3 and 21 days post-surgery. In MMT animals, development of cartilage lesions at 21 days was prevented and number of partial erosions was significantly reduced by treatment with mu-dHACM. EPIC-mu CT analysis quantitatively showed that mu-dHACM reduced proteoglycan loss in MMT animals. Conclusions: mu-dHACM is rapidly sequestered in the synovial membrane following intra-articular injection and attenuates cartilage degradation in a rat OA model. These data suggest that intra-articular delivery of mu-dHACM may have a therapeutic effect on OA development.