title: Expression of nerve growth factor is upregulated in the rat thymic epithelial cells during thymus regeneration following acute thymic involution.
abstract: Neuroimmune networks in the thymic microenvironment are thought to be involved in the regulation of T cell development. Nerve growth factor (NGF) is increasingly recognized as a potent immunomodulator, promoting "cross-talk" between various types of immune system cells. The present study describes the expression of NGF during thymus regeneration following acute involution induced by cyclophosphamide in the rat. Immunohistochemical stain demonstrated not only the presence of NGF but also its upregulated expression mainly in the subcapsular, paraseptal, and perivascular epithelial cells, and medullary epithelial cells including Hassall's corpuscles in both the normal and regenerating thymus. Biochemical data obtained using Western blot and RT-PCR supported these results and showed that thymic extracts contain NGF protein and mRNA, at higher levels during thymus regeneration. Thus, our results suggest that NGF expressed in these thymic epithelial cells plays a role in the T lymphopoiesis associated with thymus regeneration during recovery from acute thymic involution.
authors.affiliation: Department of Anatomy, Pusan National University School of Medicine, Seo-Gu, Busan, South Korea.
authors.forename: Hee-Woo
authors.initials: HW
authors.lastname: Lee
authors.forename: Sung-Min
authors.initials: SM
authors.lastname: Kim
authors.forename: Na-Ri
authors.initials: NR
authors.lastname: Shim
authors.forename: Soo-Kyung
authors.initials: SK
authors.lastname: Bae
authors.forename: Il-Gun
authors.initials: IG
authors.lastname: Jung
authors.forename: Jong-Young
authors.initials: JY
authors.lastname: Kwak
authors.forename: Bong-Seon
authors.initials: BS
authors.lastname: Kim
authors.forename: Jae-Bong
authors.initials: JB
authors.lastname: Kim
authors.forename: Jeon-Ok
authors.initials: JO
authors.lastname: Moon
authors.forename: Joo-Seop
authors.initials: JS
authors.lastname: Chung
authors.forename: Sik
authors.initials: S
authors.lastname: Yoon
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003520:Cyclophosphamide / Q000633:toxicity; D004847:Epithelial Cells / Q000502:physiology*; D007150:Immunohistochemistry; D008297:Male; D020932:Nerve Growth Factor / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012038:Regeneration; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013047:Specific Pathogen-Free Organisms; D013950:Thymus Gland / Q000166:cytology / Q000473:pathology / Q000502:physiology; D015854:Up-Regulation
chemical_list: D003520:Cyclophosphamide; D020932:Nerve Growth Factor