TGFB1 and Alzheimer disease: In lesional skin from dogs with AD, in addition to Th2 responses, Th1 (IFN-γ, IL-2, IL-12, IL-15, IL-18), Th17 (IL-17, IL-23) and Th22 (IL-22) axes are activated, along with regulatory cytokines such as IL-10 and TGF-β [8].