Table 3.
Examples of gene expression changes in microglia with aging.
| Reference | Age comparison | O>Y # genes | O>Y gene examples | O>Y pathways | O<Y # genes | O<Y gene examples | O<Y pathways | No change with aging | Methodology and Tools |
|---|---|---|---|---|---|---|---|---|---|
| 53 | Mouse 2 vs 15 months | 29 | C4; C1qb; Cats; Gas5 | Complement; lysosome; iron homeostasis | 6 | Acecs2 | Acetyl-CoA biosynthesis | C57BL/6NIA; bulk HPC; microarray | |
| 30 | Mouse 5 vs 24 months | 1831 | Tnf; Cxcl10; Nampt; Birc3; Cxcl9; Spp1; Arg1 | Stat3; neuroregulin-1; 5/12 classic activation markers; 24/37 alternate activation markers | 1672 | Trem2; P2ry12; Dap12; Siglech; Nlrp3 | Oxidative phosphorylation | Itgam (Cd11b); Cd14; Cd68; Icam | C57BL/6NIA; Cd11b/Cd45+; FACS sort; RNAseq |
| 86 | Mouse 2.5 vs 15-18 months | 482 | Ccl3; Pik3cd; Lyz1; Wbscr22; Rdh12; P2ry12 | Cytoplasmic membrane-bounded vesicle; regulation of proliferation; regulation of lymphocyte activation | 169 | Ccr6; Slpi; Clec4d; Ifitm1; Plbd1 | Inflammatory response; glycosamino-glycan binding; cell motility | C57BL/6J; Cd11b/Cd45+; FACS sort; microarray | |
| 39 | Mouse 4, 12, 22 months | 200-500 (varied with brain region) | Immune amplification | 10-100 (varied with brain region) | Tmem119; P2ry12; P2ry13; Fcrls | Homeostatic genes; TGFβ receptor genes; Cell adhesion/migration/motility | Bioenergetic pathways | C57BL/6J; Cd11b+; MACS selection; microarray | |
| 40 | Human 20-99 year | 50-200 depending on region | CLU; S100A8; CD14; CASP1 | Complement; TLRs | CX3CL1 | CX3CR1 | 4 brain regions; Bulk RNA; microarray | ||
| 48 | Human 13-95 year | CX3CR1; CSF1R; P2RY12; P2RY13; TREM2; TYROBP; some TLRs | Cell surface receptors for microglia-neuron crosstalk; M2a genes | M1 marker genes | Frontal Cortex; bulk RNA imputed to microglia; microarray | ||||
| 16 | Human 34-102 year | 212 | cell adhesion; axonal guidance; cell surface receptor expression | 360 | P2RY12; IL6R; TLR10 | Actin dynamics | Parietal cortex; percoll gradient separation; CD11B+/CD45int FACS sort; RNAseq | ||
| 36 | Human 50 (archived data set) vs 95 year | 1060 | C1QA; CD14; GRN; IRF7; TSPO | Amyloid fiber formation | 1174 | CD83; IL1B; NFKB1; TLR4 | TGFβ signaling | Dorsolateral prefrontal cortex (BA 9/46); CD11B+ MACS selection; RNAseq | |
| 26 | Human <30, 30-50, >50 (year) | SPP1 | Percoll gradient separation; CD45+ FACs cell sorting; single cell RNAseq |
Abbreviations: BA, Brodmann area; FACS, fluorescent cell sorting; HPC, hippocampus; MACS, positive cell selection using magnetic beads; O, old; Y, young