Changes in proliferative activity as cells move along undulating basement membranes in stratified squamous epithelium.

The filiform papillae of mouse tongue provide evidence for a flow of interphase basal cells along the basement membrane. This implies that they are aligned on that structure according to age. In addition there is a decrease in proliferative potential as the basal cells age. This is probably due at least in part to a fall in growth fraction. Such a method of basal cell replacement may exist in other stratified squamous epithelia characterized by undulating basement membranes.