Pilewski J M, Latoche J D, Arcasoy S M, Albelda S M
Department of Medicine, University of Pittsburgh, Pennsylvania 15261, USA.
Am J Physiol. 1997 Jul;273(1 Pt 1):L256-63. doi: 10.1152/ajplung.1997.273.1.L256.
Airway epithelium is subject to injury during inflammation and exposure to a variety of inhaled and infectious agents. Little is known about the expression of integrins during human airway epithelial regeneration and differentiation after injury. We therefore characterized integrin subunit expression after mechanical injury in an in vivo xenograft model of human bronchial epithelium. On the migrating cells at the edges of surface epithelial wounds, there was increased expression of the alpha v-, beta 5-, beta 6-, and alpha 5-integrin subunits. During the later phase of repair, the increased expression of alpha v-, beta 5-, and beta 6-subunits persisted, but the expression of the beta 8-subunits was restricted to basal cells. In addition, there was a redistribution of the alpha 2- and alpha 6-collagen/laminin-binding integrins to suprabasal epithelial layers. There was no expression of the beta 3- or alpha 4-integrin subunit on reparative epithelium. A similar upregulation of alpha v-, beta 5-, and beta 6-integrin receptor subunits was observed in areas of undifferentiated airway from cystic fibrosis patients. Injured epithelium was found to be significantly more susceptible to gene transfer with a recombinant adenovirus, suggesting that the increased integrin expression has implications for the acquisition of adenovirus infections and for lung-directed gene therapy.
气道上皮在炎症以及暴露于各种吸入性和感染性因子时会受到损伤。关于整合素在人类气道上皮损伤后再生和分化过程中的表达情况，我们所知甚少。因此，我们在人支气管上皮的体内异种移植模型中，对机械损伤后的整合素亚基表达进行了表征。在表面上皮伤口边缘的迁移细胞上，αv-、β5-、β6-和α5-整合素亚基的表达增加。在修复后期，αv-、β5-和β6-亚基的表达持续增加，但β8-亚基的表达仅限于基底细胞。此外，α2-和α6-胶原/层粘连蛋白结合整合素重新分布至上基底上皮层。修复上皮上未检测到β3-或α4-整合素亚基的表达。在囊性纤维化患者未分化气道区域也观察到αv-、β5-和β6-整合素受体亚基的类似上调。发现损伤上皮对重组腺病毒介导的基因转移明显更敏感，这表明整合素表达增加对腺病毒感染的获得以及肺定向基因治疗具有影响。
