ObjectiveOsteoarthritis (OA) is the most common degenerative joint disease, characterized by a progressive loss of cartilage associated with synovitis and subchondral bone remodeling. There is however no treatment to cure or delay the progression of OA. The objective of this manuscript was to provide a scoping review of the preclinical and clinical studies reporting the effect of gene therapies for OA.MethodThis review followed the JBI methodology and was reported in accordance with the PRISMA-ScR checklist. All research studies that explore in vitro, in vivo, or ex vivo gene therapies that follow a viral or non-viral gene therapy approach were considered. Only studies published in English were included in this review. There were no limitations to their date of publication, country of origin, or setting. Relevant publications were searched in Medline ALL (Ovid), Embase (Elsevier), and Scopus (Elsevier) in March 2023. Study selection and data charting were performed by two independent reviewers.ResultsWe found a total of 29 different targets for OA gene therapy, including studies examining interleukins, growth factors and receptors, transcription factors and other key targets. Most articles were on preclinical in vitro studies (32 articles) or in vivo animal models (39 articles), while four articles were on clinical trials related to the development of TissueGene-C (TG-C).ConclusionIn the absence of any DMOAD, gene therapy could be a highly promising treatment for OA, even though further development is required to bring more targets to the clinical stage.

Abnormal subchondral bone remodeling leading to sclerosis is a main feature of osteoarthritis (OA) and Osteomodulin (OMD), a proteoglycan involved in extracellular matrix mineralization, is associated to the sclerotic phenotype. However, the functions of OMD remain poorly understood, specifically in vivo. We used knock-out and overexpressing male mice for Omd and mutant zebrafish to study its roles in bone and cartilage metabolism and in the development of OA. The expression of Omd is deeply correlated to bone and cartilage microarchitectures affecting the bone volume and the onset of subchondral bone sclerosis and spontaneous cartilage lesions. Mechanistically, OMD binds to RANKL and inhibits osteoclastogenesis; thus controlling the balance of the bone remodeling. In conclusions, OMD is a key factor in subchondral bone sclerosis associated with OA. It participates in bone and cartilage homeostasis acting on the regulation of osteoclastogenesis. Targeting OMD may be a promising new and personalized approach for OA.