CHI3L1 and Alzheimer disease: Higher expression of C-reactive protein (CRP), proinflammatory cytokines IL-1β, IL-6, and TNF-α, and chitinase-3 like protein I (CHI3L1 or YKL-40) have been reported to be associated with the pathogenesis of AD (Wang et al., 2015; Kim et al., 2017; Shen et al., 2019).