title: CD44 expression in plexiform lesions of idiopathic pulmonary arterial hypertension.
abstract: Plexiform lesions in pulmonary arteries are a characteristic histological feature for idiopathic pulmonary arterial hypertension (IPAH). The pathogenesis of the plexiform lesion is not fully understood, although it may be related to endothelial cell dysfunction and local inflammation. CD44 is a cell adhesion molecule and it is also involved in angiogenesis, endothelial cell proliferation and migration. The expression of CD44 was examined in lung plexiform lesions obtained from patients with IPAH (IPAH group, n= 7) and pulmonary arterial hypertension associated with atrial septal defect (ASD-PAH group, n= 4). Expression of CD44 was detected in 49 out of 52 plexiform lesions (93%) from all patients in the IPAH group, whereas 31 plexiform lesions obtained from the ASD-PAH group lacked CD44 positivity by immunohistochemistry. In the IPAH group, CD44 was localized in the endothelial cells of microvessels within plexiform lesions and activated T cells in and around the lesions. Furthermore, T cell infiltration and endothelial cell proliferation activity were prominent in the plexiform lesions of the IPAH group, compared to those of the ASD-PAH group. These findings suggest that CD44 and activated T cell infiltration play an important role in the development of plexiform lesions particularly in IPAH.
authors.affiliation: Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Kita-ku, Okayama, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Ohta-Ogo
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Hao
authors.forename: Hatsue
authors.initials: H
authors.lastname: Ishibashi-Ueda
authors.forename: Seiichi
authors.initials: S
authors.lastname: Hirota
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Nakamura
authors.forename: Tohru
authors.initials: T
authors.lastname: Ohe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D002648:Child; D004730:Endothelium, Vascular / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism*; D006976:Hypertension, Pulmonary / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D007150:Immunohistochemistry; D008168:Lung / Q000098:blood supply; D008297:Male; D055806:Microvessels / Q000378:metabolism / Q000473:pathology; D008875:Middle Aged; D011651:Pulmonary Artery / Q000378:metabolism*; D013601:T-Lymphocytes / Q000378:metabolism / Q000473:pathology
chemical_list: D015415:Biomarkers; C497483:CD44 protein, human; D018960:Hyaluronan Receptors