TNC and psoriatic arthritis: Having established the total tenascin-C ELISA, screening was undertaken for a larger number of samples to assess levels of total tenascin-C in both healthy controls and patients suffering from a range of inflammatory or musculoskeletal diseases, including RA, scleroderma, OA, psoriatic arthritis, ankylosing spondylitis, SLE, polymyalgia rheumatic, and vasculitis.