TLR2 ligand stimulation induces less production of Th1/Th17 cytokines such as IFNγ, IL-12, and IL-17F, and more production of the Th2 cytokine IL-5 in macrophages or PBMCs of AD patients than in macrophages and PBMCs from non-AD patients. Here, TLR2 is linked to Alzheimer disease.