CCR2 and neurodegenerative disease: Microglia is a key player in neuroinflammation, and proinflammatory cytokine production responsible for progressive neuron damage and CCR2 on microglia has been implicated as a key player for proinflammatory response in many neurodegenerative diseases and thus important in regulating microglia-mediated neurotoxicity (Ghoshal et al., 2007; Terry et al., 2012; Kim et al., 2016; Chauhan et al., 2017; Käufer et al., 2018; Zhang et al., 2019).