Kaarteenaho-Wiik Riitta, Sademies Outi, Pääkkö Paavo, Risteli Juha, Soini Ylermi
Department of Internal Medicine, University of Oulu and Oulu University Hospital, PO Box 5000, FIN-90014 Oulu, Finland.
Hum Pathol. 2007 Jan;38(1):147-53. doi: 10.1016/j.humpath.2006.07.001. Epub 2006 Sep 25.
Sarcoidosis, atypical mycobacteriosis, and tuberculosis are common diseases of human lung with a typical feature of formation of granulomas. The structure of granulomas has not been elucidated completely. We studied the expression of tenascin-C, precursor proteins of collagens I and III, and the presence of myofibroblasts in granulomas of sarcoidosis, atypical mycobacteriosis, and tuberculosis of human lung. Twenty-five histologic samples of lung were analyzed by immunohistochemistry using antibodies to tenascin-C and aminoterminal propeptides of collagens I and III. To identify the myofibroblast-type cells in granulomas, the sections were also stained with antibodies against alpha-smooth muscle actin, vimentin, and desmin. In every case, tenascin-C and precursor proteins of collagens I and III were expressed around granulomas. Precursor protein of collagen I was expressed also within them. In tuberculosis and atypical mycobacteriosis, expression of tenascin-C and precursor protein of collagen I was stronger than in sarcoidosis. The cells demarcating granulomas and, thus, colocalizing with tenascin-C and both collagen precursors were positive for alpha-smooth muscle actin and vimentin, which suggests that these cells are myofibroblasts. They were also more abundantly present in tuberculosis and atypical mycobacteriosis, as suggested by alpha-smooth muscle actin staining. We concluded that tenascin-C and precursor proteins of collagens I and III are expressed around granulomas in sarcoidosis, atypical mycobacteriosis, and tuberculosis of the lung; and furthermore, their expression colocalize with the expression of myofibroblasts. Our results further point to the fact that fibrogenesis and matrix turnover is stronger in tuberculosis and atypical mycobacteriosis than in sarcoidosis.
结节病、非典型分枝杆菌病和结核病是人类肺部的常见疾病，具有肉芽肿形成的典型特征。肉芽肿的结构尚未完全阐明。我们研究了结节病、非典型分枝杆菌病和人类肺部结核病肉芽肿中肌腱蛋白-C、I型和III型胶原蛋白前体蛋白的表达以及肌成纤维细胞的存在情况。使用针对肌腱蛋白-C以及I型和III型胶原蛋白氨基末端前肽的抗体，通过免疫组织化学分析了25份肺组织学样本。为了识别肉芽肿中的肌成纤维细胞型细胞，切片还用抗α-平滑肌肌动蛋白、波形蛋白和结蛋白的抗体进行了染色。在每种情况下，肌腱蛋白-C以及I型和III型胶原蛋白前体蛋白均在肉芽肿周围表达。I型胶原蛋白前体蛋白在肉芽肿内部也有表达。在结核病和非典型分枝杆菌病中，肌腱蛋白-C和I型胶原蛋白前体蛋白的表达比结节病中更强。界定肉芽肿并因此与肌腱蛋白-C和两种胶原蛋白前体共定位的细胞对α-平滑肌肌动蛋白和波形蛋白呈阳性，这表明这些细胞是肌成纤维细胞。如α-平滑肌肌动蛋白染色所示，它们在结核病和非典型分枝杆菌病中也更为丰富。我们得出结论，肌腱蛋白-C以及I型和III型胶原蛋白前体蛋白在结节病、非典型分枝杆菌病和肺部结核病的肉芽肿周围表达；此外，它们的表达与肌成纤维细胞的表达共定位。我们的结果进一步表明，结核病和非典型分枝杆菌病中的纤维生成和基质周转比结节病更强。
