AGO2 and systemic lupus erythematosus: In detail, AGO2 Abs have been described in 3-24% of SLE patients, 3-32% of scleroderma/systemic sclerosis patients, 0-9% of rheumatoid arthritis patients, and 8-13% of primary SjS patients (9), and 0-9% of polymyositis/dermatomyositis patients (10), but also in 5% of hepatitis B virus or hepatitis B+C virus coinfected patients (18), and 3% of breast cancer patients (19).