S100B and complement 3 glomerulopathy: In addition, C4-convertase (C4-Nef), as well as C5-convertase (C5-Nef), targeting autoantibodies are described in C3 glomerulopathy (Corvillo et al. 2019; Noris et al. 2019; Marinzoni et al. 2017; Smith et al. 2019; Zhao et al. 2019; Zipfel et al. 2020).