Fig. 2. Human adult palm keratinocyte populations, separated by rapid and slow adhesion to type IV collagen, show different desmosomal protein expression. Two cell populations, separated by rapid (<20 minutes, lane 1) or slow (>20 minutes-24 hours, lane 2) adhesion to type IV collagen, were analysed by western blotting for the desmosomal proteins Dp, Dsgs, Dscs, Pg and Pkp1. Non-separated cells were used as the control (lane 3). The graph shows densitometric analysis of eight blots from five experiments on Dp expression (mean±s.e.m.). Note Dp expression in the slowly adhering cell population is about fourfold that of the rapidly adhering cell population. Control cells show an intermediate level of expression as expected. Similar expression profiles were observed for the other desmosomal proteins. ß-actin demonstrates equal loading of the protein samples.