Centre for Research in Vascular Biology, Australian Institute for Bioengineering and Nanotechnology, University of Queensland, St. Lucia, QLD 4072, Australia.
Am J Pathol. 2010 Jan;176(1):369-80. doi: 10.2353/ajpath.2010.090545. Epub 2009 Dec 11.
Implantation of sterile foreign objects in the peritoneal cavity of an animal initiates an inflammatory response and results in encapsulation of the objects by bone marrow-derived cells. Over time, a multilayered tissue capsule develops with abundant myofibroblasts embedded in extracellular matrix. The present study used the transgenic MacGreen mouse to characterize the time-dependent accumulation of monocyte subsets and neutrophilic granulocytes in the inflammatory infiltrate and within the tissue capsule by their differential expression of the csf1r-EGFP transgene, F4/80, and Ly6C. As the tissue capsule developed, enhanced green fluorescent protein-positive cells changed from rounded to spindle-shaped morphology and began to co-express the myofibroblast marker alpha-smooth muscle actin. Expression increased with time: at day 14, 11.13 +/- 0.67% of tissue capsule cells co-expressed these markers, compared with 50.77 +/- 12.85% of cells at day 28. The importance of monocyte/macrophages in tissue capsule development was confirmed by clodronate-encapsulated liposome removal, which resulted in almost complete abrogation of capsule development. These results confirm the importance of monocyte/macrophages in the tissue response to sterile foreign objects implanted in the peritoneal cavity. In addition, the in vivo plasticity of peritoneal macrophages and their ability to transdifferentiate from a myeloid to mesenchymal phenotype is demonstrated.
将无菌异物植入动物的腹腔会引发炎症反应，导致骨髓来源的细胞将异物包裹起来。随着时间的推移，会形成一个具有丰富肌成纤维细胞的多层组织囊，这些细胞嵌入细胞外基质中。本研究利用 MacGreen 转基因小鼠，通过 csf1r-EGFP 转基因、F4/80 和 Ly6C 的差异表达，来描述单核细胞亚群和嗜中性粒细胞在炎症浸润和组织囊内随时间的积累情况。随着组织囊的形成，增强型绿色荧光蛋白阳性细胞从圆形变为梭形形态，并开始共同表达肌成纤维细胞标志物α-平滑肌肌动蛋白。表达随时间增加：在第 14 天，有 11.13 +/- 0.67%的组织囊细胞共同表达这些标志物，而在第 28 天，有 50.77 +/- 12.85%的细胞共同表达这些标志物。单核细胞/巨噬细胞在组织囊形成中的重要性通过氯膦酸盐包裹的脂质体去除得到了证实，这导致囊形成几乎完全被阻断。这些结果证实了单核细胞/巨噬细胞在无菌异物植入腹腔后对组织反应的重要性。此外，还证明了腹膜巨噬细胞在体内的可塑性及其从骨髓样向间充质样表型转分化的能力。
