C3 and diabetic kidney disease: We found an increased expression of Cxcl1 and Cxcl2, encoding proinflammatory chemokines that stimulate monocyte infiltration (Pichler et al., 2017), and of C3, C6 and C7 genes, which are part of the complement system known to be activated in human DKD (Woroniecka et al., 2011; Ju et al., 2013; Sircar et al., 2018; Yiu et al., 2018).