The Harry M. Zweig Memorial Fund for Equine Research

Harnessing the Immunomodulatory Properties of Interleukin-10 through a Gene Therapy Approach to Prevent Equine Osterarthritis

Principal Investigator: Kyla Ortved with Alan Nixon
Contact Information: Email:; Phone: 607-253-3030
Project Costs: $28,814
Project Period: 1/1/2015-12/31/2015

         Kyla Ortved                              
The broad objective of this two year proposal is to investigate the potential therapeutic role of the immunomodulatory cytokine, interleukin-10 (IL-10), using a gene therapy approach, in the prevention and treatment of post-traumatic osteoarthritis (OA) in the horse. OA is most commonly a consequence of traumatic injury to the articular surface, which occurs frequently in equine athletes. It is a progressive, debilitating disease that is estimated to affect 60% of horses in the USA and is responsible for substantial economic loss in the equine industry. Following joint injury, chondrocytes undergo a shift in the balance between anabolism and catabolism, with decreased production extra-cellular matrix (ECM) and increased production of inflammatory
mediators and degradative enzymes. Progressive degradation of the articular surface leads to pain, stiffness and lack of mobility, which culminates in functional failure of the joint. Currently there are no effective disease-modifying drugs to halt or reverse OA once the process begins, therefore, therapeutic interventions that interfere with the early inflammatory changes that occur in the posttraumatic joint would be of great benefit. Interleukin- 10, a cytokine with potent anti-inflammatory effects, has been shown by our group and others, to have antiinflammatory effects in the joint and to play a role in ECM homeostasis. A gene therapy approach using an adeno-associated virus (AAV) vector to overexpress IL-10 represents a feasible method of delivering sustained, high doses of this cytokine to the joint environment. We hypothesize that IL-10 will modulate the global inflammatory response in the posttraumatic joint and that overexpression of this cytokine following injury will help protect the joint from secondary OA. This hypothesis will be tested in two specific aims:

Aim 1: Investigate the protective effects of AAV-mediated IL-10 overexpression in chondrocytes and synoviocytes cultured in inflammatory 3-dimensional, explant and co-culture systems;

Aim 2: Evaluate the in vivo effects of direct intra-articular injection of rAAV5-IL-10 into the equine carpal joint after induction of OA using a
validated carpal chip model. Response of cell and explant cultures will be evaluated by quantifying gene expression, protein synthesis and biochemical content of the ECM using qPCR, ELISA, flow cytometry, and histology. The second aim will be carried out in vivo using a previously validated carpal chip model for OA in
the horse and treatment outcomes will be measured through clinical examinations and synovial fluid analyses over a 56 day period. Cartilage and synovium will then be evaluated using pathology scores, gene expression analysis, biochemical assays, histology and immunohistochemistry.