Basic fibroblast growth factor in the primary olfactory pathway: mitogenic effect on ensheathing cells

Area of Science:

• Neuroscience
• Cell Biology
• Histology

Background:

• Olfactory ensheathing cells (OECs) are crucial for olfactory nerve regeneration.
• Basic fibroblast growth factor (bFGF) and nerve growth factor (NGF) are implicated in neural development and repair.
• The role of bFGF and NGF in OEC proliferation requires further elucidation.

Purpose of the Study:

• To investigate the mitogenic effects of bFGF and NGF on OEC cultures.
• To identify potential in vivo sites for OEC proliferation within the olfactory system.

Main Methods:

• Bromodeoxyuridine uptake assay to measure OEC proliferation.
• Immunohistochemical staining to detect bFGF expression in olfactory tissues.
• Cell culture experiments to assess the role of perlecan.

Main Results:

• bFGF (10 ng/ml) induced a threefold increase in OEC proliferation, significantly more than NGF.
• Perlecan, expressed by OECs, mediates high-affinity binding of bFGF to cell receptors.
• bFGF was localized in the lamina propria and olfactory epithelium, and on the periphery of nerve bundles in the olfactory nerve layer.

Conclusions:

• bFGF is a potent mitogen for OECs in vitro.
• The presence of bFGF in the lamina propria and olfactory epithelium suggests these are potential sites for OEC proliferation in vivo.
• Perlecan plays a role in mediating the proliferative effects of bFGF on OECs.