IL22 and Alzheimer disease: The Th2 cytokines; IL-4, IL-5, IL-9, IL-13, IL-31, as well as IL-22, which is also produced by Th22 cells; are produced excessively during the acute phase of AD (Henderson et al., 2008; Gittler et al., 2012; Wynn, 2015; Gandhi et al., 2016).