Two-photon laser scanning microscopy of epithelial cell-modulated collagen density in engineered human lung tissue
Two-photon laser scanning microscopy of epithelial cell-modulated collagen density in engineered human lung tissue
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DOI：
10.1089/107632701300062813
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发表时间：
2001-04-01
影响因子：
--
通讯作者：
George, SC
中科院分区：
文献类型：
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作者：
Agarwal, A;Coleno, ML;George, SC
组织重塑是一个复杂的过程，可以发生在响应于伤口或损伤。在肺组织中，异常重塑可导致永久性结构变化，其是重要肺部疾病如间质性肺纤维化和支气管哮喘的特征。成纤维细胞介导的三维胶原凝胶收缩被认为是组织收缩和重塑的体外模型，并且上皮被认为是调节该过程的一个因素。我们使用双光子激光扫描显微镜（TPLSM）研究了上皮细胞对胶原密度和收缩的影响。TPLSM用于成像人呼吸道粘膜的工程组织模型中胶原纤维的自发荧光-人肺成纤维细胞（CCD-18 lu）、变性I型胶原和单层人肺泡上皮细胞系（A549）或人支气管上皮细胞系（16 HBE 14 o（-））的三维共培养物。在第1天、第8天和第15天在组织内的10个深度处对组织进行成像。凝胶收缩与TPLSM成像同时测量。图像分析显示，没有上皮的凝胶具有最快的荧光信号衰减速率，对应于最高的胶原蛋白密度。凝胶收缩测定的结果显示，没有上皮的凝胶也具有最高程度的收缩（19.8% +/-4.0%）。我们的结论是，上皮细胞调节胶原密度和工程人肺组织的收缩，和TPLSM是一个有效的工具来研究这一现象。
Tissue remodeling is a complex process that can occur in response to a wound or injury. In lung tissue, abnormal remodeling can lead to permanent structural changes that are characteristic of important lung diseases such as interstitial pulmonary fibrosis and bronchial asthma. Fibroblast-mediated contraction of three-dimensional collagen gels is considered an in vitro model of tissue contraction and remodeling, and the epithelium is one factor thought to modulate this process. We studied the effects of epithelium on collagen density and contraction using two-photon laser scanning microscopy (TPLSM). TPLSM was used to image autofluorescence of collagen fibers in an engineered tissue model of the human respiratory mucosa-a three-dimensional co-culture of human lung fibroblasts (CCD-18 lu), denatured type I collagen, and a monolayer of human alveolar epithelial cell line (A549) or human bronchial epithelial cell line (16HBE14o(-)). Tissues were imaged at days 1, 8, and 15 at 10 depths within the tissue. Gel contraction was measured concurrently with TPLSM imaging. Image analysis shows that gels without an epithelium had the fastest rate of decay of fluorescent signal, corresponding to highest collagen density. Results of the gel contraction assay show that gels without an epithelium also had the highest degree of contraction (19.8% +/- 4.0%). We conclude that epithelial cells modulate collagen density and contraction of engineered human lung tissue, and TPLSM is an effective tool to investigate this phenomenon.