Sakata Noriyuki, Nabeshima Kazuki, Iwasaki Hiroshi, Tashiro Tadashi, Uesugi Noriko, Nakashima Osamu, Ito Hiroyuki, Kawanami Takemi, Furuya Kiyomi, Kojima Masaru
Department of Pathology, School of Medicine, Fukuoka University, 45-1, 7-chome Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan.
Pathol Res Pract. 2007;203(1):21-9. doi: 10.1016/j.prp.2006.08.008. Epub 2006 Nov 15.
To clarify the role of myofibroblasts in the development of inflammatory aortic aneurysm (IAA), 11 cases of IAA (69.2+/-8.59 years) were investigated immunohistochemically and were morphometrically compared with 12 age-matched cases of atherosclerotic abdominal aneurysm (AAA, 69.6+/-5.94 years). The positivity of mantle sign and CRP was significantly higher in the IAA group than in the AAA group. The wall of IAA (5.41+/-1.47 mm) was significantly thicker than that of AAA (2.68+/-0.71 mm). A significant increase in the expression of alpha-smooth muscle actin was found in adventitial fibroblasts of IAA compared to those of AAA. The cell density and MIB-1 index of adventitial myofibroblasts were significantly higher in IAA than in AAA (cell density: 1.69+/-0.51 vs. 1.09+/-0.4 x 10(3) cells/mm(2); MIB-1 index: 5.25+/-2.97% vs. 1.55+/-0.71%). IAA showed a significantly lower area ratio (MAR) of adventitial microvessels than did AAA (2.92+/-1.49% vs. 7.51+/-2.64%). However, there was no significant difference in microvessel density (MVD) between IAA and AAA (84.62+/-50.5 vs. 65.1+/-32.6 vessels/mm(2)). In some cases of IAA, adventitial myofibroblasts expressed hypoxia-inducible factor 1alpha in their cytoplasm or nuclei while it was not detected in AAA. These findings suggest that the development of IAA may be partly mediated by the proliferation of adventitial myofibroblasts, which might be related to tissue hypoxia.
为阐明肌成纤维细胞在炎性主动脉瘤（IAA）发生发展中的作用，对11例IAA患者（年龄69.2±8.59岁）进行了免疫组织化学研究，并与12例年龄匹配的动脉粥样硬化性腹主动脉瘤（AAA，年龄69.6±5.94岁）患者进行了形态学比较。IAA组套膜征和CRP的阳性率显著高于AAA组。IAA的管壁（5.41±1.47mm）明显厚于AAA（2.68±0.71mm）。与AAA相比，IAA外膜成纤维细胞中α-平滑肌肌动蛋白的表达显著增加。IAA中外膜肌成纤维细胞的细胞密度和MIB-1指数显著高于AAA（细胞密度：1.69±0.51对1.09±0.4×10³个细胞/mm²；MIB-1指数：5.25±2.97%对1.55±0.71%）。IAA外膜微血管的面积比（MAR）显著低于AAA（2.92±1.49%对7.51±2.64%）。然而，IAA和AAA之间的微血管密度（MVD）无显著差异（84.62±50.5对65.1±32.6个血管/mm²）。在一些IAA病例中，外膜肌成纤维细胞在其细胞质或细胞核中表达缺氧诱导因子1α，而在AAA中未检测到。这些发现表明，IAA的发生发展可能部分由外膜肌成纤维细胞的增殖介导，这可能与组织缺氧有关。
