Fig. 1
Levels of cytokines in patients with systemic lupus erythematosus (SLE) and a population of control subjects. Levels of (a) interferon (IFN)-λ1 and (b) IFN-α are significantly higher in patients with SLE (Mann-Whitney U test). c–e The cytokines interleukin (IL)-17A, IL-23, and interferon-γ-induced protein 10 (IP-10) are all expressed at higher levels in patients with SLE (Mann-Whitney U test). f The levels of IFN-λ1 are independent of the levels of IFN-α in the analysis of the whole cohort (n = 522) (Spearman’s rank correlation test). g No correlation was observed between the levels of IFN-λ1 and IFN-α in patients with SLE (Spearman’s rank correlation test). Data on cytokine concentrations are presented in log10 scale. The dashed boxes indicate individuals with high expression levels of each investigated cytokine (a–e) or double-high IFN-λ1 and IFN-α (g). The limit for high expression was set at the 75th percentile for IFN-λ1, IFN-α, IL-23, and IP-10. For IL-17A, the limit for high was set at the 90th percentile. Medians are indicated by horizontal lines, and IQRs are indicated by whiskers (90th percentile for IL-17A)