Sigler R E, Newkirk C, McDowell E M
Department of Pathology, University of Maryland School of Medicine, Baltimore 21201.
Virchows Arch B Cell Pathol Incl Mol Pathol. 1988;55(1):47-55. doi: 10.1007/BF02896559.
The formation of epidermoid metaplasia was studied in hamster tracheal epithelium in long-term serum-free organ explant culture. Explants were cultured up to 5 weeks in CMRL 1066 with antibiotics and amphotericin B. At 3 weeks there were rare small foci of epidermoid metaplasia and they became larger and more numerous at 4 and 5 weeks. Three dimensional reconstructions from serial sections demonstrated that the small deep-seated foci were discrete and did not reach the epithelial surface, whereas the larger foci were expansive and involved the full thickness of the explant epithelium. Each small focus consisted of a few swollen electron-lucent basal cells attached to the basal lamina, covered by a layer of flattened electron-dense secretory cells which formed a tight-fitting cap over the basal cells. The altered secretory cells displayed moderately well-developed rough endoplasmic reticulum and tonofilament bundles. During the early stages of formation the deep-seated metaplastic foci were completely covered by a layer of normal appearing cuboidal to low-columnar secretory and ciliated cells. Expansion of the metaplastic foci occurred by addition of flattened, electron-dense secretory cells to the cap so that multiple layers of altered secretory cells covered a core of basal cells, analogous to the structure of an onion. The secretory cells became cornified and with time the foci broke through the columnar mucociliary surface layer. In well-advanced foci, the uppermost cornified squames (metaplastic secretory cells) exfoliated into the tracheal lumen. The study emphasizes similarities and differences between the morphogenesis and histogenesis of epidermoid metaplasia in vivo and in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)
在长期无血清器官外植体培养中，研究了仓鼠气管上皮中表皮样化生的形成。将外植体在含有抗生素和两性霉素B的CMRL 1066中培养长达5周。3周时出现罕见的小表皮样化生灶，4周和5周时病灶变大且数量增多。连续切片的三维重建显示，小的深部病灶是离散的，未到达上皮表面，而较大的病灶则不断扩展，累及外植体上皮的全层。每个小病灶由一些附着于基膜的肿胀、电子透明的基底细胞组成，上面覆盖着一层扁平的、电子致密的分泌细胞，这些细胞在基底细胞上形成紧密贴合的帽状结构。改变后的分泌细胞显示出中等程度发育良好的粗面内质网和张力丝束。在形成的早期阶段，深部化生灶完全被一层外观正常的立方状至低柱状分泌和纤毛细胞覆盖。化生灶的扩展是通过在帽状结构上添加扁平的、电子致密的分泌细胞实现的，这样多层改变后的分泌细胞覆盖了基底细胞的核心，类似于洋葱的结构。分泌细胞发生角化，随着时间的推移，病灶突破柱状黏液纤毛表层。在进展良好的病灶中，最上层的角化鳞片（化生的分泌细胞）脱落到气管腔内。该研究强调了体内和体外表皮样化生的形态发生和组织发生之间的异同。（摘要截短于250字）
