Tracking & Reporting Cellular Age Using Population Doubling Level & Not Cell Passage Number

Often, cellular age is tracked by the number of times a cell has been passaged. However, cell passage number is imprecise because different labs may use different initial cell seeding densities which affect the number of times cells divide in culture. It is generally accepted that tracking the population doubling level (PDL) or cumulative population doublings (CPD) of primary cells is a best practice for reporting cellular age in vitro.

Here we explain explain how passage number and population doubling level are related and how varying cell culture techniques can create a divergence in the reporting of a cell passage number compared to PDL. We provide guidance and tools to help labs adopt the best practice of tracking PDL of cell cultures to help bring standardization to their own experimental protocols as well as to the field.