毒素触发的脂质体用于控制抗生素的释放,以治疗与革兰氏阴性菌伴放线放线杆菌相关的感染。
Toxin-triggered liposomes for the controlled release of antibiotics to treat infections associated with the gram-negative bacterium, Aggregatibacter actinomycetemcomitans.
机构信息
Department of Chemical and Biomolecular Engineering, Lehigh University, 5 E Packer Ave, Bethlehem, PA 18015, USA.
Department of Chemical and Biomolecular Engineering, Lehigh University, 5 E Packer Ave, Bethlehem, PA 18015, USA.
出版信息
Colloids Surf B Biointerfaces. 2024 Jun;238:113870. doi: 10.1016/j.colsurfb.2024.113870. Epub 2024 Mar 21.
Antibiotic resistance has become an urgent threat to health care in recent years. The use of drug delivery systems provides advantages over conventional administration of antibiotics and can slow the development of antibiotic resistance. In the current study, we developed a toxin-triggered liposomal antibiotic delivery system, in which the drug release is enabled by the leukotoxin (LtxA) produced by the Gram-negative pathogen, Aggregatibacter actinomycetemcomitans. LtxA has previously been shown to mediate membrane disruption by promoting a lipid phase change in nonlamellar lipids, such as 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-methyl (N-methyl-DOPE). In addition, LtxA has been observed to bind strongly and nearly irreversibly to membranes containing large amounts of cholesterol. Here, we designed a liposomal delivery system composed of N-methyl-DOPE and cholesterol to take advantage of these interactions. Specifically, we hypothesized that liposomes composed of N-methyl-DOPE and cholesterol, encapsulating antibiotics, would be sensitive to LtxA, enabling controlled antibiotic release. We observed that liposomes composed of N-methyl-DOPE were sensitive to the presence of low concentrations of LtxA, and cholesterol increased the extent and kinetics of content release. The liposomes were stable under various storage conditions for at least 7 days. Finally, we showed that antibiotic release occurs selectively in the presence of an LtxA-producing strain of A. actinomycetemcomitans but not in the presence of a non-LtxA-expressing strain. Together, these results demonstrate that the designed liposomal vehicle enables toxin-triggered delivery of antibiotics to LtxA-producing strains of A. actinomycetemcomitans.
近年来,抗生素耐药性已成为医疗保健领域的一个紧迫威胁。药物传递系统的使用相对于传统的抗生素给药方式具有优势,并且可以减缓抗生素耐药性的发展。在当前的研究中,我们开发了一种毒素触发的脂质体抗生素传递系统,其中药物的释放是由革兰氏阴性病原体伴放线放线杆菌产生的白细胞毒素(LtxA)触发的。先前已经表明,LtxA 通过促进非层状脂质(例如 1,2-二油酰基-sn-甘油-3-磷酸乙醇胺-N-甲基(N-甲基-DOPE))中的脂质相变为药物释放提供了有利条件。此外,已经观察到 LtxA 与含有大量胆固醇的膜强烈且几乎不可逆地结合。在这里,我们设计了一种由 N-甲基-DOPE 和胆固醇组成的脂质体传递系统,以利用这些相互作用。具体而言,我们假设由 N-甲基-DOPE 和胆固醇组成的、包封抗生素的脂质体将对 LtxA 敏感,从而实现抗生素的控制释放。我们观察到由 N-甲基-DOPE 组成的脂质体对低浓度 LtxA 的存在敏感,并且胆固醇增加了内容物释放的程度和动力学。脂质体在各种储存条件下至少稳定 7 天。最后,我们表明抗生素的释放仅在存在产生 LtxA 的 A. actinomycetemcomitans 菌株的情况下发生,而在不存在不表达 LtxA 的菌株的情况下不发生。综上所述,这些结果表明,所设计的脂质体载体能够实现毒素触发的抗生素向产生 LtxA 的 A. actinomycetemcomitans 菌株的传递。