Muñoz-Pinto Dany, Whittaker Peter, Hahn Mariah S
Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843-3122, USA.
Ann Otol Rhinol Laryngol. 2009 Apr;118(4):299-306. doi: 10.1177/000348940911800411.
In this study, we quantitatively examined cell density, collagen types I and III, and regional variations in collagen fiber thickness and orientation in the human midmembranous vocal fold lamina propria (LP).
Lamina propria samples were solubilized with proteinase K or with cyanogen bromide. Cell density was assessed in proteinase K digests by measuring DNA and normalizing it to tissue total protein. Collagen types I and III were quantified by enzyme-linked immunosorbent assay-based detection of collagen type-specific peptides generated by cyanogen bromide digestion. In addition, LP total collagen was determined by measuring sample hydroxyproline levels. Variations in collagen fiber thickness and orientation with LP region were evaluated by examining picrosirius red-stained LP sections with circularly polarized light.
The mean (+/-SEM) cell density in the LP and associated epithelium was approximately 0.57 +/- 0.09 million cells per milligram of tissue total protein. Collagen type III composed an average of 34% to 40% of LP total collagen. Quantitative histology indicated that the superficial LP contained an average of 70% thin, 26% intermediate, and 4% thick collagen fibers. This is in contrast to the intermediate and deep LPs, each of which contained less than 25% thin and more than 50% thick collagen fibers. The angular deviations in collagen fiber orientation were relatively large and were similar in magnitude across all LP layers.
The total cell density of the LP and associated epithelium was intermediate between that of hyaline cartilage and dermis. The ratio of collagen type III to total collagen in the LP was similar to that of highly elastic lung parenchyma and roughly twice that of the comparatively less-elastic dermis. The average thickness of collagen fibers increased markedly with increasing LP depth, and the relatively large angular deviations in fiber orientation appeared to correspond in part to the crimped nature of LP collagen fibers.
在本研究中，我们定量检测了人膜性中段声带固有层（LP）中的细胞密度、I型和III型胶原蛋白，以及胶原纤维厚度和方向的区域差异。
固有层样本用蛋白酶K或溴化氰溶解。通过测量DNA并将其标准化为组织总蛋白，在蛋白酶K消化物中评估细胞密度。I型和III型胶原蛋白通过基于酶联免疫吸附测定法检测溴化氰消化产生的胶原蛋白特异性肽来定量。此外，通过测量样本羟脯氨酸水平来测定LP总胶原蛋白。通过用圆偏振光检查天狼星红染色的LP切片，评估胶原纤维厚度和方向随LP区域的变化。
LP及相关上皮中的平均（±SEM）细胞密度约为每毫克组织总蛋白0.57±0.09百万个细胞。III型胶原蛋白平均占LP总胶原蛋白的34%至40%。定量组织学表明，浅表LP平均含有70%的细胶原纤维、26%的中等胶原纤维和4%的粗胶原纤维。这与中间层和深层LP形成对比，中间层和深层LP各自含有少于25%的细胶原纤维和多于50%的粗胶原纤维。胶原纤维方向的角度偏差相对较大，并且在所有LP层中大小相似。
LP及相关上皮的总细胞密度介于透明软骨和真皮之间。LP中III型胶原蛋白与总胶原蛋白的比例与高弹性肺实质相似，约为弹性相对较小的真皮的两倍。胶原纤维的平均厚度随着LP深度的增加而显著增加，并且纤维方向相对较大的角度偏差似乎部分对应于LP胶原纤维的卷曲性质。
