Comparison of IFNλ1 mRNA and protein levels between SLE and NC. The methods employed to detect expression levels of IFNλ1 mRNA and protein levels are described in Materials and methods. (a) IFNλ1 mRNA levels were significantly elevated in SLE patients versus NC. (b) Serum IFNλ1 protein levels were significantly elevated in SLE patients versus NC. Each symbol represents an individual patient and healthy donor. Horizontal lines indicate median values. IFNλ1, interferon λ1; NC, normal control; SLE, systemic lupus erythematosus.