Table 1.
Notable senescence markers and methods used for their detection.
| Senescent Cell Feature | Biomarker | Marker Level Change | Senescence Type | Detection Method |
|---|---|---|---|---|
| morphological changes | morphology, size | wide and flattened | general | light microscopy, FC |
| lysosomal activity | SA-β-galactosidase | increased | general | enzymatic staining |
| SA-α-fucosidase | increased | general | enzymatic staining | |
| Lipofuscin | increased | general | SBB, GL13 | |
| DNA damage, DDR | γH2AX | increased | general/damage-induced | IF |
| Mre11 | increased | general/damage-induced | IF | |
| Rad50 | increased | general/damage-induced | IF | |
| NSB1 | increased | general/damage-induced | IF | |
| ATM | increased | general/damage-induced | IF | |
| ATR | increased | general/damage-induced | IF | |
| 53BP1 | increased | general/damage-induced | IF | |
| MDC1 | increased | general/damage-induced | IF | |
| Rad17 | increased | general/damage-induced | IF | |
| TIF | increased | general/damage-induced | IF | |
| low/lack of DNA synthesis | BrdU | decreased | general | staining incorporation, IF |
| EdU | decreased | general | staining incorporation, IF | |
| lack of proliferation | Ki67 | decreased | general | IHC, IF |
| p16/pRB pathway | p16INK4a | increased | general | WB, IHC, IF |
| pRB | increased | general | WB, IHC, IF | |
| phospho-pRB | increased | general | WB, IHC, IF | |
| p53/p21 pathway | p53 | increased | general/damage-induced | WB, IHC, IF |
| p21 | increased | general/damage-induced | WB, IHC, IF | |
| phospho-p21 | increased | general/damage-induced | WB, IHC, IF | |
| DEC1 | increased | general/damage-induced | IHC, IF, special assay | |
| PPP1A | increased | general/damage-induced | IHC, special assay | |
| ROS | ROS | increased | general/oxidative stress-induced | fluorometry, FC |
| telomere length | telomere | decreased | replicative-induced | qPCR, FISH |
| SAHFs | SAHFs | increased | general/damage-induced | DAPI/Hoechst, confocal microscopy |
| HP1-gamma | increased | general/damage-induced | IF, IHC | |
| H3K9-methylation | increased | general/damage-induced | IF | |
| PML bodies | increased | general/damage-induced | IF | |
| nuclear membrane | lamin B1 | decreased | general | WB, IF, qPCR |
| cytokine secretion | SASPs | increased | damage-/oncogene-induced | WB, ELISA, SASP-assay |
| others | plasma membrane proteins | increased | general/replicative-/oncogene-induced | IF, WB, IHC, FC |
| apoptosis elimination | absent | general | IF, IHC |