title: Role of CD13/aminopeptidase N in rat lymphocytic alveolitis caused by thoracic irradiation.
abstract: CD13/aminopeptidase N is a cell surface glycoprotein that is widely distributed in a variety of mammalian cells. It was recently shown to have chemotactic activity for T lymphocytes. This study examined the role of CD13/aminopeptidase N in lymphocytic alveolitis in radiation-induced lung injury caused by a single-dose thoracic irradiation (15 Gy) in rats. Significantly increased aminopeptidase activity was detected in bronchoalveolar lavage fluid obtained from irradiated rats at 4 weeks after irradiation compared to the activity in unirradiated rats. Significantly higher aminopeptidase activity was detected on alveolar macrophages from irradiated rats at 2 and 4 weeks than on those from unirradiated rats. Western blot analysis showed an increased expression of CD13/aminopeptidase N protein in alveolar macrophages from irradiated rats at 4 weeks. Chemotactic activity for normal rat lymphocytes was detected in bronchoalveolar lavage fluid from irradiated rats at 4 weeks, and approximately 60% of the activity was inhibited by pretreatment of bronchoalveolar lavage fluid with bestatin, a specific aminopeptidase inhibitor. This study suggests that CD13/aminopeptidase N may play an important role as a lymphocyte chemoattractant in lymphocyte-mediated alveolitis in experimental radiation-induced lung injury.
authors.affiliation: Third Department of Internal Medicine, School of Medicine, Tokushima University, Tokushima, Japan.
authors.forename: Luping
authors.initials: L
authors.lastname: Huang
authors.forename: Kenji
authors.initials: K
authors.lastname: Tani
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Ogushi
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Ogawa
authors.forename: Teruki
authors.initials: T
authors.lastname: Shimizu
authors.forename: Yumi
authors.initials: Y
authors.lastname: Motoki
authors.forename: Hiroki
authors.initials: H
authors.lastname: Moriguchi
authors.forename: Saburo
authors.initials: S
authors.lastname: Sone
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D018826:CD13 Antigens / Q000037:antagonists & inhibitors / Q000502:physiology*; D002630:Chemotactic Factors / Q000032:analysis; D002634:Chemotaxis, Leukocyte / Q000528:radiation effects*; D007930:Leucine / Q000031:analogs & derivatives* / Q000494:pharmacology; D008168:Lung / Q000528:radiation effects; D008214:Lymphocytes / Q000276:immunology*; D016676:Macrophages, Alveolar / Q000201:enzymology; D011480:Protease Inhibitors / Q000494:pharmacology; D011658:Pulmonary Fibrosis / Q000201:enzymology* / Q000209:etiology / Q000473:pathology; D011833:Radiation Injuries, Experimental / Q000201:enzymology* / Q000209:etiology / Q000473:pathology; D017564:Radiation Pneumonitis / Q000201:enzymology* / Q000209:etiology / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D013047:Specific Pathogen-Free Organisms
chemical_list: D002630:Chemotactic Factors; D011480:Protease Inhibitors; D018826:CD13 Antigens; D007930:Leucine; C012211:ubenimex