BTG3 and arthritic joint disease: We measured arthritis disease severity, flare intensity, pain, and disability, then plasma antibody levels of rheumatoid factor IgM, anti-cyclic citrullinated peptide (CCP), anti-citrullinated α-enolase peptide 1 (CEP-1), anti-nuclear antibody (ANA), anti-citrullinated vimentin (Sa), and immunoglobulins produced in response to chikungunya, Zika and Mayaro.