Recent studies suggest that human derived intestinal epithelial cells (IECs) cultured as polarized monolayers on Transwell^® filters may respond differently when exposed to hazardous and non-hazardous proteins. This experimental platform was based on apical exposure of IEC monolayers to test proteins for 24 h followed by assessment of barrier integrity and cell viability. In this study, Caco-2 and T84 IEC polarized monolayers were evaluated for barrier integrity and cytotoxicity following exposure to hazardous and non-hazardous proteins for 24, 48 and 72 h. Hazardous proteins included Clostridium difficile toxin A (ToxA), Streptolysin O (SLO), Wheat Germ Agglutinin (WGA), and Phaseolus vulgaris haemagglutinin-E (PHA-E). Non-hazardous proteins included bovine serum albumin (BSA), porcine serum albumin (PSA), and fibronectin (Fbn). In general, evidence of diminished barrier integrity or cell viability observed following exposure to hazardous proteins for 24 h was more pronounced after 48 and 72 h for both IEC monolayers. Non-hazardous proteins exhibiting no impact following 24 h of exposure elicited minimal effects over longer exposure durations. These results support the utility of using cultured human IEC polarized monolayers to differentiate between hazardous and non-hazardous proteins and suggest that longer durations of exposure may further improve the ability to distinguish between them.

最近的研究表明，对人来源的极化单层培养于Transwell小肠上皮细胞（的IEC）^®滤波器当暴露于危险和非危险蛋白质可以有不同的反应。该实验平台是基于IEC单层的顶端暴露于测试蛋白24小时，然后评估屏障完整性和细胞活力。在这项研究中，评估了Caco-2和T84 IEC极化单层在暴露于危险和非危险蛋白质24、48和72小时后的屏障完整性和细胞毒性。有害蛋白包括艰难梭菌毒素A（ToxA），链球菌溶血素O（SLO），小麦胚芽凝集素（WGA）和菜豆血凝素E（PHA-E）。非危险蛋白包括牛血清白蛋白（BSA），猪血清白蛋白（PSA）和纤连蛋白（Fbn）。通常，两个IEC单层在暴露于危险蛋白24 h后观察到的屏障完整性或细胞活力降低的证据在48 h和72 h后更为明显。暴露24小时后无害的蛋白质无影响，在更长的暴露时间内所产生的影响最小。这些结果支持使用培养的人IEC极化单层来区分有害蛋白和非有害蛋白的实用性，并表明更长的暴露时间可能会进一步提高区分它们的能力。