Immunohistochemical study on the distribution of β-defensin 1 and β-defensin 2 throughout the respiratory tract of healthy rats

• Published in: Journal of Veterinary Medical Science Vol. 80; no. 3; pp. 395 - 404
• Main Authors: MASUDA, Natsumi, MANTANI, Youhei, YUASA, Hideto, YOSHITOMI, Chiaki, ARAI, Masaya, NISHIDA, Miho, QI, Wang-Mei, KAWANO, Junichi, YOKOYAMA, Toshifumi, HOSHI, Nobuhiko, KITAGAWA, Hiroshi
• Format: Journal Article
• Language: English
• Published: Japan JAPANESE SOCIETY OF VETERINARY SCIENCE 2018; Japan Science and Technology Agency; The Japanese Society of Veterinary Science
• Subjects: Acinar cells; Alveoli; Anatomy; bactericidal substance; Bronchus; Defensins; Epithelial cells; Epithelium; Glands; Goblet cells; host defense; Immunohistochemistry; Larynx; Mucosa; Mucus; mucus layer; Nose; Rats; respiratory organ; Respiratory tract; Rodents; secretory cell; Small intestine; respiratory organ; mucus layer; secretory cell; bactericidal substance; host defense
• ISSN: 0916-7250; 1347-7439
• DOI: 10.1292/jvms.17-0686

The distributions of β-defensin 1 and 2 in secretory host defense system throughout respiratory tract of healthy rats were immunohistochemically investigated. In the nasal epithelium, a large number of non-ciliated and non-microvillous cells (NCs) were immunopositive for both β-defensin 1 and 2, whereas a small number of goblet cells (GCs) were immunopositive only for β-defensin 1. Beta-defensin 2-immunopositive GCs were few. In the nasal glands, a small number of acinar cells and a large number of ductal epithelial cells were immunopositive for both β-defensins. In the laryngeal and tracheal epithelia, a very few NCs and GCs were immunopositive for both β-defensins. In laryngeal and tracheal glands, a very few acinar cells and a large number of ductal epithelial cells were immunopositive for both β-defensins. In the extra-pulmonary bronchus, a small number of NCs were immunopositive for both β-defensins. A small number of GCs were immunopositive for β-defensin 1, whereas few GCs were immunopositive for β-defensin 2. From the intra-pulmonary bronchus to alveoli, a very few or no epithelial cells were immunopositive for both β-defensins. In the mucus and periciliary layers, β-defensin 1 was detected from the nose to the extra-pulmonary bronchus, whereas β-defensin 2 was weakly detected only in the nose and the larynx. These findings suggest that the secretory sources of β-defensin 1 and 2 are mainly distributed in the nasal mucosa and gradually decrease toward the caudal airway in healthy rats.