YWHAQ and rheumatoid arthritis: In a population-based study, RA patients exhibited elevated serum levels of 14-3-3η protein at 3.26 ng/mL, a stark contrast to the 0.37 ng/mL in healthy controls.158 These levels correlated positively with baseline radiographic damage, suggesting 14-3-3η as a potential RA biomarker.159 The question then arises: what is the specific role of 14-3-3η in RA, and what is the source of 14-3-3 in RA patient serum and synovial fluid?