To determine the role of global Mφ, regardless of polarization state, in AKI, studies have been performed using depletion methods based on: (1) repeated administration of Mφ-depleting agents (clodronate, small molecule CSF-1R inhibitors, neutralizing anti-CSF-1R antibodies, etc.); (2) genetic deletion of Mφ survival factors (CSF-1, IL-34 or CSF-1R deficiency) (Lenda et al., 2003; Ma et al., 2009; Baek et al., 2015). The gene discussed is IL34; the disease is acute kidney injury.