不同支架材料构建组织工程化口腔黏膜的比较

目的比较3种不同支架材料———聚羟基乙酸(PGA)、胶原膜和脱细胞真皮基质材料(A lloderm)在构建组织工程化口腔黏膜方面的特点。方法体外培养、扩增人口腔黏膜上皮细胞和成纤维细胞(OFC)。呈对数生长期的OFC接种至PGA支架上培养7 d后,将口腔黏膜上皮细胞分别与PGA-OFC、胶原膜和A lloderm复合,液面下培养47~d后,进行气-液界面培养7 d。光镜、电镜下进行组织形态学及超微结构观察。结果以PGA为支架构建的组织工程化口腔黏膜,含类似上皮层和固有层,但细胞层次不清;胶原膜上可见口腔黏膜上皮细胞黏附生长,并形成复层上皮样组织,但无成熟的桥粒及基底膜样结构;以A llo-derm作为支架材料的构建物,出现正常上皮形态,含半桥粒及细胞指状突起等超微结构。结论PGA、胶原膜和A lloderm支架材料都能构建出含上皮层和固有层的口腔黏膜样组织;胶原膜由于降解速度和不易操作等特点,而不适宜作为组织工程化口腔黏膜支架材料;A lloderm作为支架的构建物更接近于人类正常口腔黏膜。

Comparison of Tissue-Engineered Oral Mucosa with Different Scaffolds

Objective To develop and compare tissue-engineered oral mucosa with scaffolds of polyglycolic acid(PGA),collagen membrane and human cadaveric dermis(Alloderm) ex vivo. Methods Oral keratinocytes(OKCs) and fibroblasts were isolated,cultured and proliferated.Tissue-engineered oral mucosa were reconstructed by seeding human oral fibroblast(OFC) onto PGA cultured for 7 days,and seeding human OKCs on PGA-OFC,collagen membrane and Alloderm,respectively.They were cultured for 4-7 days submerged and then for another 7 days at air-liquid interface.Samples of the composites were taken for histological examination at day 7 and day 14 since OKCs were seeded. Results Multi-layer epithelia without hemidesmosome and basal membrane were observed in composites of PGA showing ill-defined cell layers.OKCs could adhere and proliferate onto collagen membrane forming multi-layer epithelia,with no mature hemidesmosome and basal membrane.That of Alloderm showed normal epithelial structures,with hemidesmosome,basal membrane and cell pseudopod in lamina propria.(Conclusion)Tissue-engineered oral mucosa could be reconstructed with the scaffolds of PGA,collagen membrane and Alloderm.Collagen membrane is easy to degenerate and seems to be unsuitable for tissue-engineered oral mucosa.However,the composites with Alloderm resemble normal human oral mucosa better.