HLA-E and Alzheimer disease: Transcriptome profiling showed that genes associated with angiogenesis (i.e., CLDN5, ERG, FLT1, and VWF) and antigen presentation—especially MHC-I (major histocompatibility complex class I) machinery (i.e., HLA-E)—were enriched in these three AD-up-regulated subpopulations (Fig. 5C and SI Appendix, Table S5).