IL17A and Alzheimer disease: Th2 expansion has been shown in peripheral blood in paediatric AD, without other polar T‐cell subsets in the blood; in contrast, adult profiles showed Th2 and Th22 polarization.27 In infant skin there was a Th2 response but also innate and IL‐17‐related inflammation.28 Nonlesional, clinically unaffected skin in both adults and children has increased expression levels of cytokines with as high, or even higher levels in children compared with adults.28, 29