Rotoli Bianca Maria, Bussolati Ovidio, Bianchi Massimiliano G, Barilli Amelia, Balasubramanian Chidambara, Bellucci Stefano, Bergamaschi Enrico
Department of Experimental Medicine, Unit of General and Clinical Pathology, University of Parma, via Volturno 14, 43100 Parma, Italy.
Toxicol Lett. 2008 May 5;178(2):95-102. doi: 10.1016/j.toxlet.2008.02.007. Epub 2008 Mar 4.
Little information is available upon the effects of carbon nanotubes (CNT) on the airway barrier. Here we study the barrier function of Calu-3 human airway epithelial cells, grown on permeable filters, after the exposure to commercial single-walled or multi-walled CNT, produced through chemical vapour deposition. To assess changes in the paracellular permeability of CNT-treated Calu-3 monolayers, we have measured the trans-epithelial electrical resistance (TEER) and the permeability to mannitol. Multi-walled CNT caused a large decrease in TEER and an increase in mannitol permeability but no substantial alteration in monolayer viability. Single-walled CNT produced much smaller changes of TEER while CNT, synthesized through the arc discharge method, and Carbon Black nanoparticles had no effect. If commercial multi-walled CNT were added during the formation of the tight monolayer, no further increase in trans-epithelial resistance was observed. Moreover, the same nanomaterials, but neither single-walled counterparts nor Carbon Black, prevented the TEER recovery observed after the discontinuation of interleukin-4, a Th2 cytokine that causes a reversible barrier dysfunction in airway epithelia. These findings suggest that commercial multi-walled CNT interfere with the formation and the maintenance of tight junctional complexes in airway epithelial cells.
关于碳纳米管（CNT）对气道屏障的影响，目前可用信息较少。在此，我们研究了在可渗透滤膜上生长的Calu-3人呼吸道上皮细胞在暴露于通过化学气相沉积法生产的商用单壁或多壁碳纳米管后的屏障功能。为了评估碳纳米管处理后的Calu-3单层细胞旁细胞通透性的变化，我们测量了跨上皮电阻（TEER）和甘露醇通透性。多壁碳纳米管导致TEER大幅下降和甘露醇通透性增加，但单层细胞活力没有实质性改变。单壁碳纳米管引起的TEER变化要小得多，而通过电弧放电法合成的碳纳米管和炭黑纳米颗粒则没有影响。如果在紧密单层形成过程中加入商用多壁碳纳米管，则未观察到跨上皮电阻进一步增加。此外，相同的纳米材料，但单壁对应物和炭黑均无此作用，它们阻止了在停用白细胞介素-4后观察到的TEER恢复，白细胞介素-4是一种Th2细胞因子，可导致气道上皮细胞出现可逆性屏障功能障碍。这些发现表明，商用多壁碳纳米管会干扰气道上皮细胞紧密连接复合物的形成和维持。
