REDISTRIBUTION OF THE HEMIDESMOSOME COMPONENTS ALPHA-6-BETA-4 INTEGRIN AND BULLOUS PEMPHIGOID ANTIGENS DURING EPITHELIAL WOUND-HEALING
REDISTRIBUTION OF THE HEMIDESMOSOME COMPONENTS ALPHA-6-BETA-4 INTEGRIN AND BULLOUS PEMPHIGOID ANTIGENS DURING EPITHELIAL WOUND-HEALING
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DOI：
10.1006/excr.1993.1166
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发表时间：
1993-07-01
影响因子：
3.7
通讯作者：
STEPP, MA
中科院分区：
文献类型：
--
作者：
GIPSON, IK;SPURRMICHAUD, S;STEPP, MA
当层状鳞状上皮的基底细胞因损伤而迁移时，它们失去了细胞-基质粘附连接，即半底粒。我们在此报道了一项研究，以确定半脂质体成分α6β4整合素和大疱性类天疱疮抗原（BPAGs）的命运，这些抗原被大疱性类天疱疮自身抗血清（BPA）识别，在迁移上皮中。此外，我们报道了一些研究，以确定α6β4的相对合成和数量是否在迁移过程中发生改变。将直径1.5 ~ 2mm的中央上皮清创小鼠角膜在体外修复1 ~ 18小时。为了进行α6 - β4的预包埋免疫电镜定位，在器官培养后，从角膜基底层取出固定和迁移的角膜上皮片。用双酚a和α6和β4抗体对活体愈合的完整角膜冷冻切片进行免疫荧光显微镜观察，发现α6和β4从半粒内聚集的位置重新分布到迁移上皮前沿尖端基底细胞底物相关膜内更均匀的分布。在前缘尖端的后面，基底细胞将整合素抗体结合在整个膜周围。bpag从固定上皮的基底细胞膜移动到迁移细胞的细胞质内的扩散位置，在迁移的前沿。定量免疫沉淀和免疫印迹法检测固定和迁移上皮中α6 - β4和β1整合素的合成和总量。在静止上皮和迁移上皮中，α6 - β4和β1的相对合成量在每毫克蛋白质或每个细胞中没有差异，尽管迁移上皮中蛋白质合成率增加，但β4和β1的总量没有变化。综上所述，这些研究表明，随着半粒体的解体，其聚集的整合素组分在基底细胞膜上的分布更加均匀，BPA识别的与中间丝相关的组分从基底细胞膜释放出来，而这些事件发生时α6 - β4组分的合成和总量没有明显的变化。
As basal cells of stratified squamous epithelia become migratory in response to wounding, they lose their cell-substrate adhesion junctions, the hemidesmosomes. We report here studies to determine the fate of the hemidesmosome components, α6β4integrin and the bullous pemphigoid antigens (BPAGs), as recognized by bullous pemphigoid autoantisera (BPA), in migrating epithelium. In addition, we report studies to determine whether relative synthesis and amount of α6β4is altered during migration. Mouse corneas with 1.5- to 2-mm-diameter central epithelial debridements were allowed to healin vitroorin vivofor 1-18 h. In order to do preembedding immunoelectron microscopic localization of α6β4, sheets of stationary and migrating corneal epithelium were removed from their basal laminae after organ culture. BPA and antibodies to α6and β4were used for immunofluorescence microscopy on frozen sections of intact corneas healingin vivo1-18 h. Both α6and β4were found to redistribute from their clustered location within hemidesmosomes to a more even distribution within the substrate-associated membrane of basal cells of the tip of the leading edge of migrating epithelium. Behind the tip of the leading edge, basal cells bound the integrin antibodies around their entire membrane. BPAGs moved from their location along the basal cell membrane of stationary epithelium to a diffuse location within the cytoplasm of migrating cells at the leading edge of migration. Quantitative immunoprecipitation and immunoblotting of α6β4as well as β1integrin from stationary and migrating epithelium were done to determine whether the synthesis or total amount of the integrins were altered during migration. The relative syntheses of α6β4and β1per milligram of protein or per cell do not appear to differ between stationary and migrating epithelium and the total amount of the β4and β1does not change despite increased rates of protein synthesis in migrating epithelium. Taken together, these studies suggest that as hemidesmosomes disassemble, their clustered integrin component distributes more evenly in the basal cell membrane, the components recognized by BPA and associated with intermediate filaments are released from the membrane, and these events occur in the absence of any measurable change in the synthesis or total amount of the α6β4component.