A growing number of studies show an association between neurodegenerative processes and immune changes, both in the central nervous system (CNS) and in the periphery[26], and genetic studies indicate that markers of immunity such as variants of complement receptor 1, triggering receptor expressed on myeloid cells 2 (TREM2) and clusterin genes are risk factors for late-onset AD[27-29]. Here, CR1 is linked to Alzheimer disease.