CXCL9 and Alzheimer disease: The mRNA expression levels of 10 chemokine genes (Ccl3, Ccl5, Ccl8, Ccrl2, Cx3cr1, Cxcl1, Cxcl9, Cxcl10, Cxcl13, and Cxcl16) were upregulated along with age and reached a significant level of differential expression at the late stage of AD.