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Lund PM, Kristensen K, Larsen NW, Knuhtsen A, Hansen MB, Hjørringgaard CU, Eriksen AZ, Urquhart AJ, Mortensen KI, Simonsen JB, Andresen TL, Larsen JB. Tuning the double lipidation of salmon calcitonin to introduce a pore-like membrane translocation mechanism. J Colloid Interface Sci 2024; 669:198-210. [PMID: 38713958 DOI: 10.1016/j.jcis.2024.04.093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 04/10/2024] [Accepted: 04/14/2024] [Indexed: 05/09/2024]
Abstract
A widespread strategy to increase the transport of therapeutic peptides across cellular membranes has been to attach lipid moieties to the peptide backbone (lipidation) to enhance their intrinsic membrane interaction. Efforts in vitro and in vivo investigating the correlation between lipidation characteristics and peptide membrane translocation efficiency have traditionally relied on end-point read-out assays and trial-and-error-based optimization strategies. Consequently, the molecular details of how therapeutic peptide lipidation affects it's membrane permeation and translocation mechanisms remain unresolved. Here we employed salmon calcitonin as a model therapeutic peptide and synthesized nine double lipidated analogs with varying lipid chain lengths. We used single giant unilamellar vesicle (GUV) calcein influx time-lapse fluorescence microscopy to determine how tuning the lipidation length can lead to an All-or-None GUV filling mechanism, indicative of a peptide mediated pore formation. Finally, we used a GUVs-containing-inner-GUVs assay to demonstrate that only peptide analogs capable of inducing pore formation show efficient membrane translocation. Our data provided the first mechanistic details on how therapeutic peptide lipidation affects their membrane perturbation mechanism and demonstrated that fine-tuning lipidation parameters could induce an intrinsic pore-forming capability. These insights and the microscopy based workflow introduced for investigating structure-function relations could be pivotal for optimizing future peptide design strategies.
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Affiliation(s)
- Philip M Lund
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Kasper Kristensen
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Nanna W Larsen
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Astrid Knuhtsen
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Morten B Hansen
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Claudia U Hjørringgaard
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Anne Z Eriksen
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Andrew J Urquhart
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Kim I Mortensen
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Jens B Simonsen
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Thomas L Andresen
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.
| | - Jannik B Larsen
- Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, Lyngby, Denmark; DTU Health Tech, Department of Health Technology, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.
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2
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Steigenberger J, Mergen C, De Roo V, Geudens N, Martins JC, Heerklotz H. The effect of membrane thickness on the membrane permeabilizing activity of the cyclic lipopeptide tolaasin II. Front Mol Biosci 2022; 9:1064742. [PMID: 36619163 PMCID: PMC9817028 DOI: 10.3389/fmolb.2022.1064742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Accepted: 11/21/2022] [Indexed: 12/25/2022] Open
Abstract
Tolaasin II is an amphiphilic, membrane-active, cyclic lipopeptide produced by Pseudomonas tolaasii and is responsible for brown blotch disease in mushroom. To better understand the mode of action and membrane selectivity of tolaasin II and related lipopeptides, its permeabilizing effect on liposomes of different membrane thickness was characterized. An equi-activity analysis served to distinguish between the effects of membrane partitioning and the intrinsic activity of the membrane-bound peptide. It was found that thicker membranes require higher local peptide concentrations to become leaky. More specifically, the mole ratio of membrane-bound peptide per lipid needed to induce 50% leakage of calcein within 1 h, Re 50, increased monotonically with membrane thickness from 0.0016 for the 14:1 to 0.0070 for the 20:1 lipid-chains. Moreover, fast but limited leakage kinetics in the low-lipid regime were observed implying a mode of action based on membrane asymmetry stress in this time and concentration window. While the assembly of the peptide to oligomeric pores of defined length along the bilayer z-axis can in principle explain inhibition by increasing membrane thickness, it cannot account for the observed limited leakage. Therefore, reduced intrinsic membrane-permeabilizing activity with increasing membrane thickness is attributed here to the increased mechanical strength and order of thicker membranes.
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Affiliation(s)
- Jessica Steigenberger
- Department of Pharmaceutics, Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany,*Correspondence: Jessica Steigenberger, ; Heiko Heerklotz,
| | - Catherine Mergen
- Department of Pharmaceutics, Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany
| | - Vic De Roo
- NMR and Structure Analysis Research Group, Department of Organic and Macromolecular Chemistry, Ghent University, Ghent, Belgium
| | - Niels Geudens
- NMR and Structure Analysis Research Group, Department of Organic and Macromolecular Chemistry, Ghent University, Ghent, Belgium
| | - José C. Martins
- NMR and Structure Analysis Research Group, Department of Organic and Macromolecular Chemistry, Ghent University, Ghent, Belgium
| | - Heiko Heerklotz
- Department of Pharmaceutics, Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany,Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada,Signaling Research Centers BIOSS and CIBSS, University of Freiburg, Freiburg, Germany,*Correspondence: Jessica Steigenberger, ; Heiko Heerklotz,
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3
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Mateos H, Mallardi A, Blasi F, Palazzo G. Interaction of surfactants with phospholipid vesicles in the low concentration regime. Colloids Surf B Biointerfaces 2022; 220:112885. [PMID: 36191409 DOI: 10.1016/j.colsurfb.2022.112885] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 09/15/2022] [Accepted: 09/25/2022] [Indexed: 10/14/2022]
Abstract
The interactions between diluted phospholipid vesicles (0.3 μM - 40 μM) and surfactants (around their cmc) have been investigated as model of the phenomena taking place when enveloped viruses are challenged by detergent formulations such as mouthwashes or dishwashing liquids. We have used negatively charged Small Unilamellar Vesicles (SUVs) to simulate the negatively charged viral envelope and surfactants with different charges: the anionic Sodium Dodecyl Sulphate (SDS), the cationic Cetylpyridinium Chloride (CPC) and the non-ionic Octaethylene glycol monodecyl ether (C10E8). Dynamic and Electrophoretic Light Scattering have been used to probe variations in size and surface charge of the vesicles. The surfactants effect on the membrane permeability was investigated by measuring the fluorescence of SUVs secluding the fluorophore calcein. All the surfactants perturb the bilayer inducing graded dye leakage. Irrespective of the chemical nature of the surfactant, the membrane leakage follows the same sigmoidal master curve when it is plotted against the ratio surfactant concentration/cmc. The membrane leakage is negligible below cmc/2 and above such a value increases up to the cmc where all the dye has been fully released. For ionic SDS and CPC the dependence of leakage halftime on such a scaled concentration is the same irrespective of the charge of the surfactant and the vesicles. The nonionic surfactant C10E8 induces the dye release from the SUV two orders-of-magnitude faster than the ionic surfactants. These results show that the rate-determining parameter for the permeabilization of the lipid bilayers is the electrostatic penalty to the flip-flop required to transport the surfactant inside the vesicle.
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Affiliation(s)
- Helena Mateos
- Chemistry Department, University of Bari "A. Moro", via Orabona 4, 70125 Bari, Italy; CSGI (Center for Colloid and Surface Science), via Orabona 4, 70125 Bari, Italy.
| | - Antonia Mallardi
- Institute for Physical and Chemical Processes, Bari Division (CNR), c/o Chemistry Department, Via Orabona 4, 70125 Bari, Italy
| | - Francesca Blasi
- Chemistry Department, University of Bari "A. Moro", via Orabona 4, 70125 Bari, Italy
| | - Gerardo Palazzo
- Chemistry Department, University of Bari "A. Moro", via Orabona 4, 70125 Bari, Italy; CSGI (Center for Colloid and Surface Science), via Orabona 4, 70125 Bari, Italy.
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4
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Hausig-Punke F, Richter F, Hoernke M, Brendel JC, Traeger A. Tracking the Endosomal Escape: A Closer Look at Calcein and Related Reporters. Macromol Biosci 2022; 22:e2200167. [PMID: 35933579 DOI: 10.1002/mabi.202200167] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 07/19/2022] [Indexed: 11/11/2022]
Abstract
Crossing the cellular membrane and delivering active pharmaceuticals or biologicals into the cytosol of cells is an essential step in the development of nanomedicines. One of the most important intracellular processes regarding the cellular uptake of biologicals is the endolysosomal pathway. Sophisticated nanocarriers have been developed overcoming a major hurdle, the endosomal entrapment, and delivering their cargo to the required site of action. In parallel, in vitro assays have been established analyzing the performance of these nanocarriers. Among them, the release of the membrane-impermeable dye calcein has become a popular and straightforward method. It is accessible for most researchers worldwide, allows for rapid conclusions about the release potential, and enables the study of release mechanisms. This review is intended to provide an overview and guidance for scientists applying the calcein release assay. It comprises a survey of several applications in the study of endosomal escape, considerations of potential pitfalls, challenges and limitations of the assay, and a brief summary of complementary methods. Based on this review, we hope to encourage further research groups to take advantage of the calcein release assay for their own purposes and help to create a database for more efficient cross-correlations between nanocarriers. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Franziska Hausig-Punke
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany.,Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany
| | - Friederike Richter
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany.,Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany
| | - Maria Hoernke
- Chemistry and Pharmacy, Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Str. 9, 79104, Freiburg i.Br., Germany
| | - Johannes C Brendel
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany.,Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany
| | - Anja Traeger
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany.,Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany
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5
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Shi S, Markl AM, Lu Z, Liu R, Hoernke M. Interplay of Fusion, Leakage, and Electrostatic Lipid Clustering: Membrane Perturbations by a Hydrophobic Antimicrobial Polycation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:2379-2391. [PMID: 35148117 DOI: 10.1021/acs.langmuir.1c03445] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Membrane active compounds are able to induce various types of membrane perturbations. Natural or biomimetic candidates for antimicrobial treatment or drug delivery scenarios are mostly designed and tested for their ability to induce membrane permeabilization, also termed leakage. Furthermore, the interaction of these usually cationic amphiphiles with negatively charged vesicles often causes colloidal instability leading to vesicle aggregation or/and vesicle fusion. We show the interplay of these modes of membrane perturbation in mixed phosphatidyl glycerol (PG)/phosphatidyl ethanolamine (PE) by the statistical copolymer MM:CO comprising, both, charged and hydrophobic subunits. MM:CO is a representative of partially hydrophobic, highly active, but less selective antimicrobial polycations. Cryo-electron microscopy indicates vesicle fusion rather than vesicle aggregation upon the addition of MM:CO to negatively charged PG/PE (1:1) vesicles. In a combination of fluorescence-based leakage and fusion assays, there is support for membrane permeabilization and pronounced vesicle fusion activity as distinct effects. To this end, membrane fusion and aggregation were prevented by including lipids with polyethylene glycol attached to their head groups (PEG-lipids). The leakage activity of MM:CO is very similar in the absence and presence of PEG-lipids. Vesicle aggregation and fusion however are largely suppressed. This strongly suggests that MM:CO induces leakage by asymmetric packing stress because of hydrophobically driven interactions which could lead to leakage. As a further membrane perturbation effect, MM:CO causes lipid clustering in model vesicles. We address potential artifacts and misinterpretations of experiments characterizing leakage and fusion. Additional to the leakage activity, the pronounced fusogenic activity of the polymer and potentially of many other similar compounds likely has implications for antimicrobial activity and beyond.
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Affiliation(s)
- Shuai Shi
- Chemistry and Pharmacy, Albert-Ludwigs-Universität, 79104 Freiburg i.Br., Germany
| | - Anja Madleine Markl
- Chemistry and Pharmacy, Albert-Ludwigs-Universität, 79104 Freiburg i.Br., Germany
| | - Ziyi Lu
- State Key Laboratory of Bioreactor Engineering, Key Laboratory for Ultrafine Materials of Ministry of Education, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Research Center for Biomedical Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Runhui Liu
- State Key Laboratory of Bioreactor Engineering, Key Laboratory for Ultrafine Materials of Ministry of Education, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Research Center for Biomedical Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Maria Hoernke
- Chemistry and Pharmacy, Albert-Ludwigs-Universität, 79104 Freiburg i.Br., Germany
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6
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Wichmann N, Lund PM, Hansen MB, Hjørringgaard CU, Larsen JB, Kristensen K, Andresen TL, Simonsen JB. Applying flow cytometry to identify the modes of action of membrane-active peptides in a label-free and high-throughput fashion. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183820. [PMID: 34813768 DOI: 10.1016/j.bbamem.2021.183820] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 10/29/2021] [Accepted: 11/12/2021] [Indexed: 06/13/2023]
Abstract
Membrane-active peptides (MAPs) have several potential therapeutic uses, including as antimicrobial drugs. Many traditional methods used to evaluate the membrane interactions of MAPs have limited applicability. Low-throughput methods, such as microscopy, provide detailed information but often rely on fluorophore-labeled MAPs, and high-throughput assays, such as the calcein release assay, cannot assess the mechanism behind the disruption of vesicular-based lipid membranes. Here we present a flow cytometric assay that provides detailed information about the peptide-lipid membrane interactions on single artificial lipid vesicles while being high-throughput (1000-2000 vesicles/s) and based on label-free MAPs. We synthesized and investigated six MAPs with different modes of action to evaluate the versatility of the assay. The assay is based on the flow cytometric readouts from artificial lipid vesicles, including the fluorescence from membrane-anchored and core-encapsulated fluorophores, and the vesicle concentration. From these parameters, we were able to distinguish between MAPs that induce vesicle solubilization, permeation (pores/membrane distortion), and aggregation or fusion. Our flow cytometry findings have been verified by traditional methods, including the calcein release assay, dynamic light scattering, and fluorescence microscopy on giant unilamellar vesicles. We envision that the presented flow cytometric assay can be used for various types of peptide-lipid membrane studies, e.g. to identify new antibiotics. Moreover, the assay can easily be expanded to derive additional valuable information.
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Affiliation(s)
- Nanna Wichmann
- Department of Health Technology, Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Philip M Lund
- Department of Health Technology, Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Morten B Hansen
- Department of Health Technology, Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Claudia U Hjørringgaard
- Department of Health Technology, Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Jannik B Larsen
- Department of Health Technology, Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Kasper Kristensen
- Department of Health Technology, Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Thomas L Andresen
- Department of Health Technology, Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.
| | - Jens B Simonsen
- Department of Health Technology, Center for Intestinal Absorption and Transport of Biopharmaceuticals, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.
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7
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Zhong Y, Bejjanki NK, Miao X, Weng H, Li Q, Zhang J, Liu T, Vannam R, Xie M. Synthesis and Photothermal Effects of Intracellular Aggregating Nanodrugs Targeting Nasopharyngeal Carcinoma. Front Bioeng Biotechnol 2021; 9:730925. [PMID: 34604188 PMCID: PMC8481884 DOI: 10.3389/fbioe.2021.730925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 09/02/2021] [Indexed: 12/25/2022] Open
Abstract
Chemotherapy for the treatment of nasopharyngeal carcinoma (NPC) is usually associated with many side effects; therefore, its treatment options have not yet been completely resolved. Improving distribution to the targeted tumor region and enhancing the cellular uptake of drugs can efficiently alleviate the above adverse medical effects. Near-infrared (NIR) laser light-mediated photothermal therapy (PTT) and photodynamic therapy (PDT) are promising strategies for cancer treatment. In the present study, we developed an efficient multifunctional nanocluster with enhanced targeting and aggregation efficiency for PTT and PDT that is composed of a biocompatible folic acid (FA), indocyanine green (ICG) and 2-cyanobenzothiazole (CBT)-functionalized peptide labeled with an aldehyde sodium alginate-modified magnetic iron oxide nanoparticle (ASA-MNP)-based nanocarrier. FA can bind to folate receptors on cancer cell membranes to enhance nanocluster uptake. CBT-modified peptide can react with glutathione (GSH), which is typically present at higher levels in cancer cells, to form intracellular aggregates and increase the local concentration of the nanodrug. In in vitro studies, these nanodrugs displayed the desired uptake capacity by NPC cells and the ability to suppress the growth of cancer cells under laser irradiation. Animal studies validated that these nanodrugs are safe and nontoxic, efficiently accumulate in NPC tumor sites following injection via the caudal vein, and shows superior inhibition of tumor growth in a tumor-bearing mouse model upon near-infrared laser irradiation. The results indicate the potential application of the multifunctional nanoparticles (NPs), which can be used as a new method for the treatment of folate receptor-positive NPC.
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Affiliation(s)
- Ying Zhong
- Department of Otolaryngology-Head and Neck Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China.,Department of Otolaryngology-Head and Neck Surgery, Zhuhai People's Hospital, Zhuhai, China
| | - Naveen Kumar Bejjanki
- Department of Otolaryngology-Head and Neck Surgery, Zhuhai People's Hospital, Zhuhai, China
| | - Xiangwan Miao
- Department of Otolaryngology-Head and Neck Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Huanhuan Weng
- Department of Thyroid Surgery, Shantou Central Hospital, Shantou, China
| | - Quanming Li
- Department of Otolaryngology-Head and Neck Surgery, Zhuhai People's Hospital, Zhuhai, China
| | - Juan Zhang
- Department of Otolaryngology-Head and Neck Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Tao Liu
- Department of Otolaryngology-Head and Neck Surgery, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Raghu Vannam
- Piramal Pharma Solutions, Riverview, MI, United States
| | - Minqiang Xie
- Department of Otolaryngology-Head and Neck Surgery, Zhujiang Hospital, Southern Medical University, Guangzhou, China.,Department of Otolaryngology-Head and Neck Surgery, Zhuhai People's Hospital, Zhuhai, China
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8
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Richter F, Leer K, Martin L, Mapfumo P, Solomun JI, Kuchenbrod MT, Hoeppener S, Brendel JC, Traeger A. The impact of anionic polymers on gene delivery: how composition and assembly help evading the toxicity-efficiency dilemma. J Nanobiotechnology 2021; 19:292. [PMID: 34579715 PMCID: PMC8477462 DOI: 10.1186/s12951-021-00994-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 08/10/2021] [Indexed: 02/02/2023] Open
Abstract
Cationic polymers have been widely studied for non-viral gene delivery due to their ability to bind genetic material and to interact with cellular membranes. However, their charged nature carries the risk of increased cytotoxicity and interaction with serum proteins, limiting their potential in vivo application. Therefore, hydrophilic or anionic shielding polymers are applied to counteract these effects. Herein, a series of micelle-forming and micelle-shielding polymers were synthesized via RAFT polymerization. The copolymer poly[(n-butyl acrylate)-b-(2-(dimethyl amino)ethyl acrylamide)] (P(nBA-b-DMAEAm)) was assembled into cationic micelles and different shielding polymers were applied, i.e., poly(acrylic acid) (PAA), poly(4-acryloyl morpholine) (PNAM) or P(NAM-b-AA) block copolymer. These systems were compared to a triblock terpolymer micelle comprising PAA as the middle block. The assemblies were investigated regarding their morphology, interaction with pDNA, cytotoxicity, transfection efficiency, polyplex uptake and endosomal escape. The naked cationic micelle exhibited superior transfection efficiency, but increased cytotoxicity. The addition of shielding polymers led to reduced toxicity. In particular, the triblock terpolymer micelle convinced with high cell viability and no significant loss in efficiency. The highest shielding effect was achieved by layering micelles with P(NAM-b-AA) supporting the colloidal stability at neutral zeta potential and completely restoring cell viability while maintaining moderate transfection efficiencies. The high potential of this micelle-layer-combination for gene delivery was illustrated for the first time.
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Affiliation(s)
- Friederike Richter
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Katharina Leer
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Liam Martin
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Prosper Mapfumo
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Jana I Solomun
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Maren T Kuchenbrod
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
| | - Stephanie Hoeppener
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany
| | - Johannes C Brendel
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany
| | - Anja Traeger
- Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldtstrasse 10, 07743, Jena, Germany.
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743, Jena, Germany.
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9
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Al Nahas K, Keyser UF. Standardizing characterization of membrane active peptides with microfluidics. BIOMICROFLUIDICS 2021; 15:041301. [PMID: 34257793 PMCID: PMC8266397 DOI: 10.1063/5.0048906] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 06/22/2021] [Indexed: 06/13/2023]
Abstract
Antimicrobial peptides (AMPs) are emerging as important players in the fight against antibiotic resistance. In parallel, the field of microfluidics has matured and its benefits are being exploited in applications of biomimetics and standardized testing. Membrane models are essential tools extensively utilized in studying the activity and modes of action of AMPs. Here, we describe how the utilization of microfluidic platforms in characterizing membrane active peptides can develop a reliable colorful image that classical techniques have rendered black and white.
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Affiliation(s)
- Kareem Al Nahas
- Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB30HE, United Kingdom
| | - Ulrich F. Keyser
- Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB30HE, United Kingdom
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10
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Ros U, Pedrera L, Garcia-Saez AJ. Techniques for studying membrane pores. Curr Opin Struct Biol 2021; 69:108-116. [PMID: 33945958 DOI: 10.1016/j.sbi.2021.03.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 03/23/2021] [Accepted: 03/27/2021] [Indexed: 01/30/2023]
Abstract
Pore-forming proteins (PFPs) are of special interest because of the association of their activity with the disruption of the membrane impermeability barrier and cell death. They generally convert from a monomeric, soluble form into transmembrane oligomers that induce the opening of membrane pores. The study of pore formation in membranes with molecular detail remains a challenging endeavor because of its highly dynamic and complex nature, usually involving diverse oligomeric structures with different functionalities. Here we discuss current methods applied for the structural and functional characterization of PFPs at the individual vesicle and cell level. We highlight how the development of high-resolution and single-molecule imaging techniques allows the analysis of the structural organization of protein oligomers and pore entities in lipid membranes.
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Affiliation(s)
- Uris Ros
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann-Strasse 26, Cologne, Germany
| | - Lohans Pedrera
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann-Strasse 26, Cologne, Germany
| | - Ana J Garcia-Saez
- Institute for Genetics and Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann-Strasse 26, Cologne, Germany.
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11
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Shi S, Quarta N, Zhang H, Lu Z, Hof M, Šachl R, Liu R, Hoernke M. Hidden complexity in membrane permeabilization behavior of antimicrobial polycations. Phys Chem Chem Phys 2021; 23:1475-1488. [DOI: 10.1039/d0cp05651k] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
There are diverse membrane permeabilization behaviors of antimicrobial polycations in zwitterionic or charged vesicles; different mechanisms may occur over time.
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Affiliation(s)
- Shuai Shi
- Chemistry and Pharmacy
- Albert-Ludwigs-Universität
- 79104 Freiburg i.Br
- Germany
| | - Ndjali Quarta
- Chemistry and Pharmacy
- Albert-Ludwigs-Universität
- 79104 Freiburg i.Br
- Germany
- Department of Chemistry, Biochemistry
| | - Haodong Zhang
- State Key Laboratory of Bioreactor Engineering
- Frontiers Science Center for Materiobiology and Dynamic Chemistry
- School of Materials Science and Engineering
- East China University of Science and Technology
- Shanghai 200237
| | - Ziyi Lu
- State Key Laboratory of Bioreactor Engineering
- Frontiers Science Center for Materiobiology and Dynamic Chemistry
- School of Materials Science and Engineering
- East China University of Science and Technology
- Shanghai 200237
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences
- 182 23 Prague
- Czech Republic
| | - Radek Šachl
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences
- 182 23 Prague
- Czech Republic
| | - Runhui Liu
- State Key Laboratory of Bioreactor Engineering
- Frontiers Science Center for Materiobiology and Dynamic Chemistry
- School of Materials Science and Engineering
- East China University of Science and Technology
- Shanghai 200237
| | - Maria Hoernke
- Chemistry and Pharmacy
- Albert-Ludwigs-Universität
- 79104 Freiburg i.Br
- Germany
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12
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Dietel L, Kalie L, Heerklotz H. Lipid Scrambling Induced by Membrane-Active Substances. Biophys J 2020; 119:767-779. [PMID: 32738218 DOI: 10.1016/j.bpj.2020.07.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/03/2020] [Accepted: 07/07/2020] [Indexed: 11/26/2022] Open
Abstract
The functional roles of the lipid asymmetry of biomembranes are attracting increasing attention. This study characterizes the activity of surfactants to induce transmembrane flip-flop of lipids and thus "scramble" this asymmetry. Detergent-induced lipid scrambling of liposomes mimicking the charge asymmetry of bacterial membranes with 20 mol % of 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-rac-glycerol in the outer leaflet only was quantified by ζ-potential measurements for octaethylene glycol dodecyl ether (C12EO8), octyl glucoside (OG), and dodecyl maltoside. Membrane leakage was separately measured by the fluorescence lifetime-based calcein leakage assay and the onset of the membrane-to-micelle transition by isothermal titration calorimetry. Partition coefficients and partial molar areas were obtained as well. For the quickly membrane-permeant C12EO8 and OG, leakage proceeds at a rather sharp threshold content in the membrane, which is well below the onset of solubilization and little dependent on incubation time; it is accompanied by fast lipid scrambling. However, unlike leakage, flip-flop is a relaxation process that speeds up gradually from taking weeks in the detergent-free membrane to minutes or less in the leaking membrane. Hence, after 24 h of incubation, 10 mol % of C12EO8 or 50 mol % of OG in the membrane suffice for virtually complete lipid scrambling, whereas leakage remains below 10% for up to 14 mol % of C12EO8 and 88 mol % of OG. There is thus a concentration window in which lipid scrambling proceeds without leakage. This implies that lipid scrambling must be considered a possible mode of action of antimicrobial peptides and other membrane-active drugs or biomolecules. A related, detergent-based protocol for scrambling the lipid asymmetry of liposomes and maybe cells without compromising their overall integrity would be a very valuable tool to study functions of lipid asymmetry.
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Affiliation(s)
- Lisa Dietel
- Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany.
| | - Louma Kalie
- Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany
| | - Heiko Heerklotz
- Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg, Germany; Signaling Research Centers BIOSS and CIBSS, University of Freiburg, Freiburg, Germany; Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada.
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13
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Stulz A, Vogt A, Saar JS, Akil L, Lienkamp K, Hoernke M. Quantified Membrane Permeabilization Indicates the Lipid Selectivity of Membrane-Active Antimicrobials. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:16366-16376. [PMID: 31710807 DOI: 10.1021/acs.langmuir.9b01849] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Most antimicrobial peptides (AMPs) and their synthetic mimics (SMAMPs) are thought to act by permeabilizing cell membranes. For antimicrobial therapy, selectivity for pathogens over mammalian cells is a key requirement. Understanding membrane selectivity is thus essential for designing AMPs and SMAMPs to complement classical antibiotics in the future. This study focuses on membrane permeabilization induced by SMAMPs and their selectivity for membranes with different lipid compositions. We measure release and fluorescence lifetime of a self-quenching dye in lipid vesicles. Apart from the dose-response, we quantify the strength of individual leakage events, and, employing cumulative kinetics, categorize permeabilization behavior. We propose that differing selectivities in a series of SMAMPs arise from a combination of the effect of the antimicrobial agent and the susceptibility of the membrane (with a given lipid composition) for certain types of leakage behavior. The unselective and hemolytic SMAMP is found to act mainly by the asymmetry stress mechanism, mediated by hydrophobic insertion of SMAMPs into lipid layers. The more selective SMAMPs induced leakage events occurring stochastically over several hours. Lipid intrinsic properties might additionally amplify the efficiency of leakage events. Leakage behavior changes with both the design of the SMAMP and the lipid composition of the membrane. Understanding how leakage behavior contributes to the selectivity and activity of antimicrobial agents will aid the design and screening of antimicrobials. An understanding of the underlying processes facilitates the comparison of membrane permeabilization across in vitro and in vivo assays.
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Affiliation(s)
- Anja Stulz
- Pharmaceutical Technology and Biopharmacy , Albert-Ludwigs-Universität , Freiburg i.Br ., Germany
| | - Annika Vogt
- Pharmaceutical Technology and Biopharmacy , Albert-Ludwigs-Universität , Freiburg i.Br ., Germany
- Faculty of Applied Chemistry , Reutlingen University , Reutlingen , Germany
| | - Julia Selina Saar
- Department of Microsystems Engineering (IMTEK) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) , Albert-Ludwigs-Universität , Freiburg i.Br ., Germany
| | - Larissa Akil
- Pharmaceutical Technology and Biopharmacy , Albert-Ludwigs-Universität , Freiburg i.Br ., Germany
| | - Karen Lienkamp
- Department of Microsystems Engineering (IMTEK) and Freiburg Center for Interactive Materials and Bioinspired Technologies (FIT) , Albert-Ludwigs-Universität , Freiburg i.Br ., Germany
| | - Maria Hoernke
- Pharmaceutical Technology and Biopharmacy , Albert-Ludwigs-Universität , Freiburg i.Br ., Germany
- BIOSS Centre for Biological Signalling Studies , Albert-Ludwigs-Universität , Freiburg i.Br ., Germany
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14
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Wimley WC, Hristova K. The Mechanism of Membrane Permeabilization by Peptides: Still an Enigma. Aust J Chem 2019; 73:96-103. [PMID: 32341596 DOI: 10.1071/ch19449] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Peptide-induced permeabilization of lipid vesicles has been measured for decades and has provided many insights into the sequence-structure-function relationships of membrane-active peptides. However, researchers in the field have noted that many experiments show transient permeabilization, in which a burst of leakage occurs immediately after peptide addition, followed by a slowdown or cessation of leakage before all contents have been released. This widely observed, but rarely studied, phenomenon is not explained by standard equilibrium pore models that are commonly invoked in both experimental and computational studies. Here we discuss observations of transient permeabilization, and we outline a pathway towards understanding this enigmatic phenomenon.
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Affiliation(s)
- William C Wimley
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112
| | - Kalina Hristova
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, and Program in Molecular Biophysics, Johns Hopkins University, Baltimore, MD 21218
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15
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Abstract
Membrane permeabilizing peptides (MPPs) are as ubiquitous as the lipid bilayer membranes they act upon. Produced by all forms of life, most membrane permeabilizing peptides are used offensively or defensively against the membranes of other organisms. Just as nature has found many uses for them, translational scientists have worked for decades to design or optimize membrane permeabilizing peptides for applications in the laboratory and in the clinic ranging from antibacterial and antiviral therapy and prophylaxis to anticancer therapeutics and drug delivery. Here, we review the field of membrane permeabilizing peptides. We discuss the diversity of their sources and structures, the systems and methods used to measure their activities, and the behaviors that are observed. We discuss the fact that "mechanism" is not a discrete or a static entity for an MPP but rather the result of a heterogeneous and dynamic ensemble of structural states that vary in response to many different experimental conditions. This has led to an almost complete lack of discrete three-dimensional active structures among the thousands of known MPPs and a lack of useful or predictive sequence-structure-function relationship rules. Ultimately, we discuss how it may be more useful to think of membrane permeabilizing peptides mechanisms as broad regions of a mechanistic landscape rather than discrete molecular processes.
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Affiliation(s)
- Shantanu Guha
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| | - Jenisha Ghimire
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| | - Eric Wu
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
| | - William C Wimley
- Department of Biochemistry and Molecular Biology Tulane University School of Medicine , New Orleans , Louisiana 70112 , United States
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16
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Selectivity of Antimicrobial Peptides: A Complex Interplay of Multiple Equilibria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1117:175-214. [DOI: 10.1007/978-981-13-3588-4_11] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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17
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de Bettencourt-Dias A, Hahm JI. Women in Nanotechnology: Toward Better Materials through a Better Understanding of Low-Dimensional Systems. ACS NANO 2018; 12:7417-7420. [PMID: 30080391 DOI: 10.1021/acsnano.8b05854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
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18
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Lei R, Hou J, Chen Q, Yuan W, Cheng B, Sun Y, Jin Y, Ge L, Ben-Sasson SA, Chen J, Wang H, Lu W, Fang X. Self-Assembling Myristoylated Human α-Defensin 5 as a Next-Generation Nanobiotics Potentiates Therapeutic Efficacy in Bacterial Infection. ACS NANO 2018; 12:5284-5296. [PMID: 29856606 DOI: 10.1021/acsnano.7b09109] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The increasing prevalence of antibacterial resistance globally underscores the urgent need to the update of antibiotics. Here, we describe a strategy for inducing the self-assembly of a host-defense antimicrobial peptide (AMP) into nanoparticle antibiotics (termed nanobiotics) with significantly improved pharmacological properties. Our strategy involves the myristoylation of human α-defensin 5 (HD5) as a therapeutic target and subsequent self-assembly in aqueous media in the absence of exogenous excipients. Compared with its parent HD5, the C-terminally myristoylated HD5 (HD5-myr)-assembled nanobiotic exhibited significantly enhanced broad-spectrum bactericidal activity in vitro. Mechanistically, it selectively killed Escherichia coli ( E. coli) and methicillin-resistant Staphylococcus aureus (MRSA) through disruption of the cell wall and/or membrane structure. The in vivo results further demonstrated that the HD5-myr nanobiotic protected against skin infection by MRSA and rescued mice from E. coli-induced sepsis by lowering the systemic bacterial burden and alleviating organ damage. The self-assembled HD5-myr nanobiotic also showed negligible hemolytic activity and substantially low toxicity in animals. Our findings validate this design rationale as a simple yet versatile strategy for generating AMP-derived nanobiotics with excellent in vivo tolerability. This advancement will likely have a broad impact on antibiotic discovery and development efforts aimed at combating antibacterial resistance.
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Affiliation(s)
- Ruyi Lei
- Department of Anesthesiology and Intensive Care, The First Affiliated Hospital, School of Medicine , Zhejiang University , Hangzhou 310003 , China
| | - Jinchao Hou
- Department of Anesthesiology and Intensive Care, The First Affiliated Hospital, School of Medicine , Zhejiang University , Hangzhou 310003 , China
| | - Qixing Chen
- The Children's Hospital, School of Medicine , Zhejiang University , Hangzhou 310052 , China
| | - Weirong Yuan
- Institute of Human Virology and Department of Biochemistry and Molecular Biology , University of Maryland School of Medicine , Baltimore , Maryland 21201 , United States
| | - Baoli Cheng
- Department of Anesthesiology and Intensive Care, The First Affiliated Hospital, School of Medicine , Zhejiang University , Hangzhou 310003 , China
| | - Yaqi Sun
- Department of Anesthesiology and Intensive Care, The First Affiliated Hospital, School of Medicine , Zhejiang University , Hangzhou 310003 , China
| | - Yue Jin
- Department of Anesthesiology and Intensive Care, The First Affiliated Hospital, School of Medicine , Zhejiang University , Hangzhou 310003 , China
| | - Lujie Ge
- Department of Anesthesiology and Intensive Care, The First Affiliated Hospital, School of Medicine , Zhejiang University , Hangzhou 310003 , China
| | - Shmuel A Ben-Sasson
- Department of Developmental Biology, Institute for Medical Research Israel-Canada , The Hebrew University-Hadassah Medical School , Jerusalem 91120 , Israel
| | - Jiong Chen
- Laboratory of Biochemistry and Molecular Biology , Ningbo University , Ningbo 315211 , China
| | - Hangxiang Wang
- Key Laboratory of Combined Multi-Organ Transplantation, Ministry of Public Health, The First Affiliated Hospital, School of Medicine , Zhejiang University , Hangzhou 310003 , China
| | - Wuyuan Lu
- Institute of Human Virology and Department of Biochemistry and Molecular Biology , University of Maryland School of Medicine , Baltimore , Maryland 21201 , United States
| | - Xiangming Fang
- Department of Anesthesiology and Intensive Care, The First Affiliated Hospital, School of Medicine , Zhejiang University , Hangzhou 310003 , China
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