CCL22 and Alzheimer disease: After stimulation with TLR2 ligands, the mRNA expression levels of regulated on activation, normal T cell expressed and secreted (RANTES)/CCL5, MCP-2/CCL8, MCP-4/CCL13, pulmonary and activation-regulated chemokine (PARC)/CCL18, and macrophage-derived chemokine (MDC)/CCL22 were higher in PBMCs from AD patients than in those from healthy controls (48)).