Elevated serum IL-37 levels in SLE patients with renal disease. Serum IL-37 levels exhibited a significant elevation in patients with renal involvement (n = 40) relative to patients without renal disease (n = 26) as well as healthy control (HC, n = 41). Each symbol represents an individual patient or healthy control. Horizontal lines indicate median values. Mann-Whitney U-test and associated P values are indicated. NS, no significant.