The research project, OA-ACTIVE aims to develop a cellular therapeutic strategy for arthropathies with the aim of regeneration and protection of cartilage in the long run. Two intraarticular therapeutic solutions will be developed and evaluated: (1) a visco-suppletion type strategy with functionalised hydroexpansive hybrid unnanogel and (2) adult stem cell secretomy (MSCs). Depending on the results obtained in this project, these two therapeutic pathways could be combined in the future to potentiate their effectiveness. This translational research project, regenerative medicineregroups 2 partners with complementary skills and recognised in their areas of expertise for cellular and tissue-scale (BIOTARGEN) and organism-wide studies (CIRALE), with the horse as a patient and model for targeted application, to meet the unmet clinical needs in the treatment of osteoarthritis. In humans, osteoarthritis is the main cause of morbidity in developed countries, significantly affecting the quality of life of patients. It would concern between 9 and 10 million people in France (Le Pen et al., 2005), 100 million in the European Union (Altman et al., 2006), generating 1.6 billion euros in 2002 for health insurance in France, making this disease a major public health problem. In horses, it is the main cause of lameness and the first cause of reduced performance or career stops for racing and sports horses (Perkins et al., 2005; Oke et al., 2010). Thus, joint diseases have a major economic impact on the sector, corresponding to about EUR 100 million per year for the Trot sector alone in France. Normandy with its 125,000 equidae (1 million equidae in France) is considered to be the French horse region for all disciplines:chevaux sports, races with for example 25 major equestrian events organised each year including 20 international events, plus intense breeding activity with 5200 farms and 12,000 births per year. The equine sector, embodied in the French Hippolia Competitiveness Pole based in Normandy in Caen, thus represents a major asset for Normandy in terms of its social, economic and tourism impact, with 1.3 billion euros in annual turnover and around 18,000 direct and indirect jobs in the region, including 6,500 companies, which are more unlocalizable, a major asset for a Region. This economic weight has led theRegion Normandy and the Departmental Council of Calvados to make major investments for more than 20 years on two platforms for research and training in equine health based in St Contest (in vitro) and inGoustranville (in vivo research). Named Normandie Equine Vallée, as the Mixed Union (Region Normandy + Departmental Council of Calvados) of the same name, owner of the sites, these platforms are today a unique ensemble in Europe. The research teams that occupy them have come together with a GIS dedicated to equine health research: the GIS Centaure is developing its research work in a “One Health” concept with 2 axes: Infectious diseases and fight against majorlocomotor diseases. In this regional context, but also internationally, arthropathies are a major focus of equine research whose stake is all the more important as the horse represents an excellent animal model for humans, internationally recognised. Thus, the development of effective therapeutic strategies for the horse, is essential for the management of arthropathies and integrates perfectly into the concept “One Health” for the health and well-being of man and horse.