Association of serum IFN-λ1 levels with SLEDAI as well as laboratory values. Each symbol represents an individual patient. (a) Serum IFN-λ1 levels were positively correlated with SLEDAI. (b) A significantly positive correlation was observed between serum IFN-λ1 levels and anti-dsDNA antibody. (c) Positive correlation was also seen between serum IFN-λ1 levels and CRP. (d) Negative relationship was observed between serum IFN-λ1 levels and C3. anti-dsDNA antibody, anti-double stranded DNA antibody; C3, complement 3; CRP, C-reactive protein; IFNλ1, interferon λ1; SLEDAI, systemic lupus erythematosus disease activity index.