Wallner B C, Harréus U A, Gamarra F, Sassen A, Kleinsasser N H
GenPharmTox BioTech AG, Martinsried.
HNO. 2005 Dec;53(12):1037-46. doi: 10.1007/s00106-005-1243-0.
Volatile and ingestive xenobiotics may induce cancer in the mucosa of the upper aerodigestive tract. A new model is presented combining mini-organ cultures of human mucosa and the Comet assay that allows investigation of tumor initiation steps in vitro.
Specimens of human mucosa of the inferior nasal turbinates were cultured as mini-organs and exposed to xenobiotics once, twice or three times with consecutive repair intervals. The cultures were monitored for structural integrity (inverse microscopy, histology), DNA fragmentation and repair activity (Comet assay), induction of apoptosis (annexin V assay), and production of IL-8 and GM-CSF (ELISA).
Mini-organ cultures showed a good structural integrity during the whole culture period. Exposure to N-nitrosodiethylamine (NDEA) and benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE) induced significant DNA fragmentation. Sodium dichromate (Na2Cr2O7) had an additive DNA fragmentation effect with repetitive exposure. Significant DNA repair was seen after strand break induction by Na2Cr2O7, only. Apoptosis was seen after three exposures to BPDE und Na2Cr2O7, but not NDEA. Inflammatory cytokine release was unaltered by NDEA. However, BPDE and Na2Cr2O7 reduced GM-CSF and Na2Cr2O7 reduced IL-8 excretion.
This three dimensional mini-organ culture system proved to be very helpful in characterizing volatile and ingestive xenobiotics potentially hazardous to humans. Beside the information concerning genotoxicity, it allows cytological and immunological studies. In contrast to investigations with fresh specimens, repetitive or chronic exposure to xenobiotics is possible in mucosal cells with their epithelial structural integrity. Therefore, mini-organ cultures of human upper aerodigestive tract epithelia represent a model closely resembling the in vivo situation.
挥发性和摄入性异生物素可能会诱发上呼吸道消化道黏膜癌症。本文提出了一种新模型，该模型结合了人类黏膜的微型器官培养和彗星试验，能够在体外研究肿瘤起始步骤。
将下鼻甲的人类黏膜标本培养成微型器官，并连续进行一次、两次或三次异生物素暴露，每次暴露后设定修复间隔期。对培养物进行结构完整性监测（倒置显微镜、组织学）、DNA片段化和修复活性检测（彗星试验）、凋亡诱导检测（膜联蛋白V检测）以及白细胞介素-8和粒细胞-巨噬细胞集落刺激因子的产生检测（酶联免疫吸附测定）。
微型器官培养物在整个培养期间显示出良好的结构完整性。暴露于N-亚硝基二乙胺（NDEA）和苯并[a]芘-7,8-二氢二醇-9,10-环氧化物（BPDE）会导致显著的DNA片段化。重铬酸钠（Na2Cr2O7）重复暴露具有累加的DNA片段化效应。仅在重铬酸钠诱导链断裂后观察到显著的DNA修复。三次暴露于BPDE和重铬酸钠后可观察到凋亡，但暴露于NDEA后未观察到凋亡。NDEA未改变炎性细胞因子的释放。然而，BPDE和重铬酸钠降低了粒细胞-巨噬细胞集落刺激因子水平，重铬酸钠降低了白细胞介素-8的分泌。
这种三维微型器官培养系统被证明对于鉴定可能对人类有害的挥发性和摄入性异生物素非常有帮助。除了提供有关遗传毒性的信息外，它还允许进行细胞学和免疫学研究。与新鲜标本研究不同，在具有上皮结构完整性的黏膜细胞中可以重复或长期暴露于异生物素。因此，人类上呼吸道消化道上皮的微型器官培养代表了一种与体内情况非常相似的模型。
