The temporal and spatial expression of basic fibroblast growth factor during ocular development in the chicken.

Purpose: The authors determined the temporal and spatial localization of basic fibroblast growth factor (bFGF) during ocular development in the chick embryo in an attempt to elucidate its role in this process.

Methods: These studies used monospecific polyclonal rabbit anti-human bFGF immunoglobulin G in conjunction with immunohistochemical techniques and western blot analysis. Embryonic eyes at 5-20 days of development were studied.

Results: The bFGF was not detected by western blot analysis until embryonic day 12. However, low levels of bFGF-immunoreactive material were present in pigmented and neural retina and the lenses of 5-day embryos. Lens epithelial and fiber cells remained weakly stained throughout development; neuroepithelial cells, ganglion cells, amacrine cells, and photoreceptors all contained significant levels of bFGF-immunoreactive material. Corneal epithelium consistently contained high levels of immunoreactive material. In the corneal endothelium, increasing levels of immunoreactive material were seen as development proceeded.

Conclusion: It was hypothesized that bFGF may be involved in regulating the proliferation and differentiation of ocular cells in either an autocrine or paracrine fashion during development and that it may play a role in tissue maintenance in the adult eye. These conclusions are consistent with the temporal and spatial expression of bFGF described here.