MLKL and systemic lupus erythematosus: Recently, Guo and co-workers observed that the activation of RIPK3 and MLKL was observed in kidney podocytes from class IV human lupus nephritis and experimental animal models such as lupus-prone NZM2328 and MRL/lpr mice, as evidenced by staining of phosphorylated forms of RIP3 and MLKL in podocytes.