Analysing Temporal Dynamics of T Cell Division in vivo Using Ki67 and BrdU Co-labelling by Flow Cytometry

This protocol was developed to increase the richness of information available from in vivo T cell proliferation studies. DNA labelling techniques such as BrdU incorporation allow precise control of label administration and withdrawal, so that the division history of a population can be tracked in detail over long timeframes (days-weeks). Ki67 is expressed in the nucleus of dividing cells, and is retained for a short time (3-4 days) after division ( Gossel et al., 2017 ); therefore acting as a molecular clock to identify cells that have recently divided. Combining these two techniques allows the integration of current and historical proliferation information from individual cells within a population. This data can subsequently be used to probe population dynamics by fitting mathematical models of proliferation ( Gossel et al., 2017 ).