Cellular Senescence Assay Kit | CBA-230

Cellular Senescence Assay Kit | CBA-230

Normal primary cells proliferate in culture for a limited number of population doublings prior to
undergoing terminal growth arrest and acquiring a senescent phenotype. This finite life span correlates
with the age of the organism and with the life expectancy of the species from which the cells were
obtained; such that the older the age or the shorter the life span, the less the ability of the cells to
undergo population doubling. Senescent cells are characterized by an irreversible G1 growth arrest
involving the repression of genes that drive cell cycle progression and the upregulation of cell cycle
inhibitorslike p16INK4a, p53, and its transcriptional target, p21CIP1
. They are resistant to mitogeninduced proliferation, and assume a characteristic enlarged, flattened morphology. Research into the
pathways that positively regulate senescence and ways cells bypass senescence is therefore critical in
understanding carcinogenesis. Normal cells have several mechanisms in place to protect against
uncontrolled proliferation and tumorigenesis.
Senescent cells show common biochemical markers such as expression of an acidic senescenceassociated ß-galactosidase (SA-ß-Gal) activity. While senescence has been characterized primarily in
cultured cells, there is also evidence that it occurs in vivo. Cells expressing markers of senescence
such as SA-ß-Gal have been identified in normal tissues.
The Cellular Senescence Assay Kit provides an easy-to-use and efficient method to determine cellular
senescence. SA-β-galactosidase catalyzes the hydrolysis of X-gal, which produces a blue color. Each
kit provides sufficient quantities to perform up to 50 assays in 35 mm dishes.

Kit Components
1. 100X Fixing Solution (Part No. 40010): One tube – 1.5 mL of 25% Glutaraldehyde
2. Staining Solution A (Part No. 40011): One tube – 1.5 mL of 500 mM Potassium Ferrocyanide
3. Staining Solution B (Part No. 40012): One tube – 1.5 mL of 500 mM Potassium Ferricyanide
4. Staining Solution C (Part No. 40015): One bottle – 4.5 mL of 1 M Citrate-Na2HPO4 Buffer, pH
6.0, 50 mM MgCl2 in each tube
5. Staining Solution D (Part No. 90016): Two tubes – 2.0 mL of 5 M NaCl in each tube
6. X-gal Solution (Part No. 40014): Two tubes – 1.5 mL of 40 mg/mL X-gal in DMF in each tube

Materials Not Supplied
1. PBS
2. 37ºC Incubator
3. Light microscope
4. Senescent cells or tissue samples
Storage
Store X-gal solution protected from light at -20ºC. Store all other components at 4ºC.