In Alzheimer's disease, the synaptic proteins synaptophysin and PSD-95 were quantified by ELISA, and the inflammatory proteins and mRNAs by MesoScale Discovery Multiplex Assays and qPCR, respectively.Systemic infection in Alzheimer's disease was associated with decreased CD16 (p = 0.027, grey matter) and CD68 (p = 0.015, white matter); increased CD64 (p = 0.017, white matter) as well as increased protein expression of IL6 (p = 0.047) and decreased IL5 (p = 0.007), IL7 (p = 0.002), IL12/IL23p40 (p = 0.001), IL15 (p = 0.008), IL16 (p < 0.001) and IL17A (p < 0.001).
Phenotype analysis revealed differences in expression of CD16 (increased in mAD), NKG2A (decreased in aMCI), and TLR2 and TLR9 (both decreased in mAD).