Endocrine Abstracts

Introduction

The main population of GnRH-1 neurons that control activity of the HPG axis in primates originate in the peripheral olfactory system. Recently, in vitro primary cell cultures from human fetal olfactory epithelium, named FNC-B4, have been shown to express GnRH-1 and are likely to be the precursor of the adult-like GnRH-1 system distribution in the CNS. A number of external and cell-autonomous factors are known to control migration of these specialized cells into the developing mammalian brain, including Pax6, NELF, ARK, KAL-1 and DCC. Among them, NELF is known to regulate GnRH-1 migratory activity in mice. However the precise role of its action over GnRH-1 cells remains unclear.

Aims

The aim was to find if NELF was produced in human GnRH-1 olfactory neuroepithelial cells.

Methods and Results

In vitro immunofluorescence techniques using specific antibodies against NELF and GnRH-1 peptides have been used in order to localize their presence in FNCB-4 cells. The results showed a clear co-localization of both peptides in the cytoplasm of the secreting neuroblasts.

Discussion and conclusions

The co-localization of NELF and GnRH-1 in FNC-B4 cell line is consistent with these cells having a migratory phenotype. The presence and action of NELF in human olfactory GnRH-1 neurons may affect the olfactory axon projections, allowing GnRH-1 cells to distinguish different pathways in the CNS and thereby facilitate establishment of the correct adult-like GnRH-1 distribution.