Nekhotiaeva Natalia, Elmquist Anna, Rajarao Gunaratna Kuttuva, Hällbrink Mattias, Langel Ulo, Good Liam
Center for Genomics and Bioinformatics, Karolinska Institutet, Berzelius väg 35, 17177 Stockholm, Sweden.
FASEB J. 2004 Feb;18(2):394-6. doi: 10.1096/fj.03-0449fje. Epub 2003 Dec 4.
Antimicrobial drug action is limited by both microbial and host cell membranes. Microbes stringently exclude the entry of most drugs, and mammalian membranes limit drug distribution and access to intracellular pathogens. Recently, cell-penetrating peptides (CPPs) have been developed as carriers to improve mammalian cell uptake. Given that CPPs are cationic and often amphipathic, similar to membrane active antimicrobial peptides, it may be possible to use CPP activity to improve drug delivery to microbes. Here, two CPPs, TP10 and pVEC, were found to enter a range of bacteria and fungi. The uptake route involves rapid surface accumulation within minutes followed by cell entry. TP10 inhibited Candida albicans and Staphylococcus aureus growth, and pVEC inhibited Mycobacterium smegmatis growth at low micromolar doses, below the levels that harmed human HeLa cells. Therefore, although TP10 and pVEC entered all cell types tested, they preferentially damage microbes, and this effect was sufficient to clear HeLa cell cultures from noninvasive S. aureus infection. Also, conversion of the cytotoxicity indicator dye SYTOX Green showed that TP10 causes rapid and lethal permeabilization of S. aureus and pVEC permeabilizes M. smegmatis, but not HeLa cells. Therefore, TP10 and pVEC can enter both mammalian and microbial cells and preferentially permeabilize and kill microbes.
抗菌药物的作用受到微生物和宿主细胞膜的限制。微生物严格限制大多数药物的进入，而哺乳动物细胞膜则限制药物的分布以及对细胞内病原体的接触。最近，细胞穿透肽（CPPs）已被开发为载体，以改善哺乳动物细胞对药物的摄取。鉴于CPPs是阳离子性的，且通常具有两亲性，类似于膜活性抗菌肽，利用CPPs的活性来改善药物向微生物的递送或许是可行的。在此，发现两种CPPs，即TP10和pVEC，可以进入多种细菌和真菌。摄取途径包括在数分钟内迅速在表面积累，随后进入细胞。TP10抑制白色念珠菌和金黄色葡萄球菌的生长，而pVEC在低微摩尔剂量下就能抑制耻垢分枝杆菌的生长，该剂量低于对人类HeLa细胞造成损害的水平。因此，尽管TP10和pVEC能进入所有测试的细胞类型，但它们优先损害微生物，这种作用足以清除HeLa细胞培养物中的非侵袭性金黄色葡萄球菌感染。此外，细胞毒性指示剂染料SYTOX Green的转化表明，TP10能使金黄色葡萄球菌迅速发生致死性通透化，pVEC能使耻垢分枝杆菌通透化，但对HeLa细胞则无此作用。因此，TP10和pVEC既能进入哺乳动物细胞也能进入微生物细胞，且优先使微生物通透化并将其杀死。
