HISTOLOGY AND HISTOPATHOLOGY

From Cell Biology to Tissue Engineering

 

Distinct presence of the tight junction protein claudin-3 in olfactory bulb and fila olfactoria of the mouse

Elisabeth Eppler, Magdalena Müller-Gerbl and I. Piotr Maly

Department of Biomedicine, University of Basel, Basel, Switzerland

Offprint requests to: Elisabeth Eppler, Department of Biomedicine, University of Basel, Basel, Switzerland. e-mail: elisabeth.eppler@unibas.ch


Summary. The tight junction protein claudin-3 is overexpressed in diverse epithelial tumours and is associated with increased survival, progression and motility of tumour cells. Claudin-3 expression profiles are being increasingly used for diagnostic and prognostic tumour classification. Claudin-3 has been identified as a receptor for Clostridium perfringens enterotoxin, which is under consideration for selective lysis of claudin-3-expressing tumours, particularly brain metastases, and other translational medicine uses. However, the localization of claudin-3 in the brain has not been completely elucidated. While claudin-3 in brain tissue adjacent to claudin-3-expressing metastases had been excluded and low or undetectable levels proposed in the CNS, under physiological conditions, in adult human, rat and mouse brains, claudin-3 was exclusively found in choroid plexus epithelium where it is considered an integral component of the blood-cerebrospinal-fluid barrier. We report here the pronounced presence of claudin-3 not only in the nasal region (as described for rat), but also in the mouse olfactory bulb and nerve using immunohistochemistry and Western blot. Claudin-3 was present in the fila olfactoria from the epithelium to the olfactory nerve and in the main and accessory olfactory bulb. We propose that the abundant presence of claudin-3 in the olfactory system, particularly in nerve fibres and the olfactory bulb cone, which we present here, may play a role at the interface of the central and peripheral nervous system, both as barrier and for axonal growth and communication. Thus, claudin-3 should be considered and further explored with regards to treatment approaches addressing the olfactory bulb and nasal region. Histol Histopathol 32, 835-849 (2017)

Key words: Claudins, Claudin-1, Claudin-2, Claudin-3, Claudin-4, Claudin-5, Occludin, Olfactory nerve, Olfactory epithelium, Nasal region

DOI: 10.14670/HH-11-854