人类催利西丁LL-37迅速破坏了结肠上皮质的完整性
Geeta Kilari1, Jacquelyn Tran1, Graham A D Blyth1
1Faculty of Veterinary Medicine, University of Calgary, Canada.
Biochimica et biophysica acta. Biomembranes
|January 21, 2025
概括
人类催利西丁LL-37通过降解紧结蛋白质,暂时增加肠道的通透性. 这一发现揭示了cathelicidin在调节对病原体的上皮屏障方面的新作用.
科学领域:
- 免疫学 免疫学 免疫学
- 细胞生物学 细胞生物学
- 胃肠病学 胃肠病学
背景情况:
- 肠道屏障对于防止病原体进入至关重要,它依赖于上皮细胞和紧结 (TJ) 蛋白.
- 凯瑟利西丁是具有已知的抗菌和免疫调节功能的抗菌,但它们对肠道完整性的影响尚不清楚.
研究的目的:
- 研究人类甲基素LL-37在调节肠上皮质屏障功能和紧结蛋白完整性方面的作用.
- 确定LL-37影响表皮透性的机制及其与肠道病原体的相互作用.
主要方法:
- 刺激人类结肠上皮 (T84) 细胞和小鼠直肠上皮 (CMT-93) 细胞,使用人类催利西丁LL-37.
- 评估上皮细胞的透性和TJ蛋白 (occludin,claudin-2) 的水平.
- 评估LL-37对TJ降解的影响,由Citrobacter rodentium诱导.
主要成果:
- LL-37通过促进内细胞结合和氧化素和Claudin-2的 lysosomal 降解,迅速和短暂地增加了T84细胞的透性.
- 鼠类甲基西丁CRAMP没有影响T84细胞的透性.
- LL-37在CMT-93细胞中加剧了C.动物诱导的透性和TJ降解,但没有显著影响细菌殖民.
结论:
- 人类催利素LL-37通过通过内分细胞和溶酶体通路降解关键的TJ蛋白质ocludin和claudin-2来破坏肠上皮质屏障的完整性.
- 在亚微生物杀伤性度下观察到的这些免疫调节效应,突出显示了cathelicidin在抗附着/消除病原体的上皮屏障调节中的新机制.
- 了解LL-37在结肠炎等疾病中的功能,可以将其确立为一种关键的抗感染免疫调节剂.
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