Targeted Therapy of Antibody-Induced Autoimmune Arthritis Using Peptide-Guided Nanoparticles.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joints and it affects over 18 million people worldwide. Despite the availability of a variety of potent drugs for RA, over 30-40 percent of patients fail to achieve adequate remission, and many patients suffer from systemic adverse effects. Thus, there is an urgent need for a joint-targeted drug delivery system. Nanotechnology-based drug delivery methods offer a promising resource that is largely untapped for RA. Using the T cell-driven rat adjuvant-induced arthritis (AA) model of human RA, we developed a peptide-targeted liposomal drug delivery system for arthritis therapy. It was based on a novel joint-homing peptide ART-2 to guide liposomes entrapping dexamethasone (Dex) to arthritic joints of rats, and this approach was more effective in suppressing arthritis than the unpackaged (free) drug. To de-risk the translation of our innovative drug delivery technology to RA patients, we undertook the validation of ART-2-liposomal delivery in a genetically and mechanistically distinct arthritis model in mice, the collagen antibody-induced arthritis (CAIA) model. Using live imaging for tissue distribution of liposomes in vivo, immunohistochemistry of paws for cellular binding of ART-2, and liposomal Dex delivery, our results fully validated the key findings of the rat model, namely, preferential homing of peptide-functionalized liposomes to arthritic joints compared to healthy joints, and higher efficacy of liposomal Dex than free Dex. These results offer a proof-of-concept for the benefits of targeted drug delivery to the joints and its potential translation to RA patients.