University of Edinburgh, Centre for Inflammation Research, Queens Medical Research Institute, 47 Little France Crescent, Edinburgh EH164TJ, UK.
Part Fibre Toxicol. 2010 Mar 22;7:5. doi: 10.1186/1743-8977-7-5.
The unique hazard posed to the pleural mesothelium by asbestos has engendered concern in potential for a similar risk from high aspect ratio nanoparticles (HARN) such as carbon nanotubes. In the course of studying the potential impact of HARN on the pleura we have utilised the existing hypothesis regarding the role of the parietal pleura in the response to long fibres. This review seeks to synthesise our new data with multi-walled carbon nanotubes (CNT) with that hypothesis for the behaviour of long fibres in the lung and their retention in the parietal pleura leading to the initiation of inflammation and pleural pathology such as mesothelioma. We describe evidence that a fraction of all deposited particles reach the pleura and that a mechanism of particle clearance from the pleura exits, through stomata in the parietal pleura. We suggest that these stomata are the site of retention of long fibres which cannot negotiate them leading to inflammation and pleural pathology including mesothelioma. We cite thoracoscopic data to support the contention, as would be anticipated from the preceding, that the parietal pleura is the site of origin of pleural mesothelioma. This mechanism, if it finds support, has important implications for future research into the mesothelioma hazard from HARN and also for our current view of the origins of asbestos-initiated pleural mesothelioma and the common use of lung parenchymal asbestos fibre burden as a correlate of this tumour, which actually arises in the parietal pleura.
石棉对胸膜间皮的独特危害引起了人们对高长径比纳米颗粒（HARN）如碳纳米管可能存在类似风险的关注。在研究 HARN 对胸膜潜在影响的过程中，我们利用了关于壁层胸膜在长纤维反应中作用的现有假说。本综述旨在将我们关于多壁碳纳米管（CNT）的新数据与关于长纤维在肺部的行为及其在壁层胸膜中的保留导致炎症和胸膜病理（如间皮瘤）的假说进行综合。我们描述了证据表明，所有沉积颗粒中的一部分到达胸膜，并且存在一种从胸膜清除颗粒的机制，通过壁层胸膜的气孔。我们认为这些气孔是长纤维保留的部位，长纤维无法通过它们，导致炎症和胸膜病理，包括间皮瘤。我们引用胸腔镜数据来支持这一论点，这正如前文所预期的那样，壁层胸膜是胸膜间皮瘤的起源部位。如果这一机制得到证实，将对未来研究 HARN 引起的间皮瘤危害以及我们目前对石棉引发的胸膜间皮瘤起源和将肺实质石棉纤维负担作为这种肿瘤的相关因素的看法产生重要影响，而实际上这种肿瘤起源于壁层胸膜。
