Chemiluminescent detection of senescence-associated β galactosidase. 
Identifying molecules that serve as markers for cell aging is a goal that has been pursued by several groups.  Senescence-associated β galactosidase (SA-βgal) staining is broadly used and very easily detected.  β-gal is a lysosomal enzyme strongly correlated to the progression of cell senescence.  Here, we describe a simple, fast, and quantitative protocol to quantify SA-βgal activity in cell lysate extracts by a chemiluminescent method using galacton as substrate.