Gürkan et al. reported significantly increased serum IL‐5 levels in infants with AD compared with controls, but did not demonstrate a correlation with disease severity.59 Eosinophils constitutively express IL‐31RA and release proinflammatory cytokines and chemokines, including IL‐1β, IL‐6, IL‐31, CXCL1, CXCL8, CCL2, CCL18 and CCL26, in response to IL‐31.60 In keeping with elevated IL‐5 levels and eosinophil activation, we found elevated levels of CCL2, IL‐1β and CXCL8 in the SC. This evidence concerns the gene CCL2 and Alzheimer disease.