The expression of Th2 cytokines (IL-4, IL-5, and IL-13) and Treg cytokines (IL-10 and IL-1β) was downregulated, whereas the expression of Th1 cytokines (IL-12, IFN-γ, and TNF-α) was upregulated, in the FMT_8w compared with the AD group. Here, IL4 is linked to Alzheimer disease.