Contrasting effects of basic fibroblast growth factor and epidermal growth factor on mouse neonatal olfactory mucosa cells.

Basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) affect proliferation and survival of many cell types, but their role in the maintenance of olfactory mucosa cells remains unclear. In the neonatal mouse olfactory mucosa, cell proliferation mainly occurs in the neuroepithelium and, to a lesser extent, in the lamina propria. To establish whether bFGF and EGF affect proliferation and/or survival of these cells, we isolated olfactory mucosa cells from the neonatal mouse and cultured them as free-floating spheres under bFGF or EGF stimulation. Our data demonstrate that bFGF is a mitogen for the rapidly dividing cells (olfactory neuronal precursors and olfactory ensheathing cells), and also a survival factor for both slowly and rapidly dividing cells of the olfactory mucosa. In contrast, EGF appears to be primarily a survival factor for both the olfactory stem and precursor cells.