大肠杆菌外膜囊泡作为AR-23抗病毒肽的呈递平台

Outer membrane vesicles from Escherichia coli as a presentation platform for AR-23 antiviral peptide.

作者信息Francesca Mensitieri, Federica Dell'Annunziata, Giulia Gaudino, Veronica Folliero, Gianluigi Franci, Fabrizio Dal Piaz, Viviana Izzo
PMID41113855
发布时间2025-10-03
DOI10.3389/fmolb.2025.1607578

实验完整度

研究包含重组蛋白表达、质谱鉴定、表面暴露验证、细胞毒性检测及抗病毒功能验证,但缺乏动物模型或体内验证。

主要模型

大肠杆菌BL21(DE3)菌株 VERO-76细胞系 HSV-1、HSV-2、SARS-CoV-2及PV-1病毒株

重点核对

ClyA-AR23融合蛋白的重组表达和OMVs表面暴露 OMVs对VERO-76细胞的细胞毒性 OMVs对HSV-1和HSV-2的剂量依赖性抑制活性 OMVs对SARS-CoV-2和PV-1的抑制效果

摘要

Introduction: Anti-microbial peptides (AMPs) are a well-established alternative among antiviral and antibacterial agents, having considerable advantages over traditional antimicrobials in terms of biocompatibility and limited resistance development. However, a general poor bioavailability and short half-life limit their large-scale implementation. In this framework, different strategies are being explored, such as AMPs encapsulation or their functionalization on antigen-presenting platforms. In this work the evaluation of Escherichia coli (E. coli) derived Outer Membrane Vesicles (OMVs) as antiviral presenting platforms is described.Methods: OMVs were engineered through the recombinant overexpression of an outer membrane chimeric protein, ClyA-AR23, obtained by combining Cytolysin A (ClyA) with the AR-23 antiviral peptide, derived from frog skin and active against herpes simplex viruses. LC-MS/MS was used to screen the presence of the recombinant protein in cells and OMVs. Plaque reduction assay after pre-incubation treatment and qPCR on viral transcript were used to evaluate ClyA-AR23 OMVs antiviral activity of the engineered vesicles.Results: The expression of ClyA-AR23 protein was verified in recombinant E. coli cells and OMVs and the surface exposure of ClyA C-terminus was confirmed. Engineered ClyA-AR23 OMVs negligible cytotoxicity effect was assessed on VERO-76 cells. Both control and functionalized OMVs were used in pre-incubation treatment with HSV-1, HSV-2, SARS-COV2 and PV-1. Results highlighted that ClyA-AR23 OMVs did effectively impair HSV-1 and HSV-2 replication cycle in a dose dependent manner.Discussion: In this work we provided a first evidence of AMPs functionalization on membrane vesicles of bacterial origin. The systems demonstrated to be active towards HSV-1 and HSV-2 viruses with negligible cytotoxicity on VERO-76 cells.

实验结论

提炼研究问题、关键发现与证据,快速把握文章的核心贡献。

研究问题
研究旨在探索大肠杆菌外膜囊泡作为AR-23抗病毒肽呈递平台的可行性,以改善其生物利用度和半衰期。
核心机制
AR-23通过ClyA融合蛋白展示在OMVs表面,其抗病毒活性可能源于与病毒包膜的直接相互作用。
主要证据
LC-MS/MS验证了ClyA-AR23蛋白在细胞和OMVs中的存在;蚀斑减少实验和qPCR显示OMVs对HSV-1和HSV-2具有剂量依赖性抑制作用,对SARS-CoV-2有部分抑制,对PV-1无抑制。
研究意义
该研究首次证实了抗菌肽在细菌来源膜囊泡上的功能化,为开发新型抗病毒递送策略提供了依据。

研究路径

按研究推进顺序梳理实验设计、验证步骤与关键观察。

1

重组表达ClyA-AR23融合蛋白

在大肠杆菌中表达ClyA-AR23嵌合蛋白,并确认其存在于细胞和OMVs中。

将ClyA与AR-23编码序列克隆至pET22b(+)载体,转化大肠杆菌BL21(DE3),经IPTG诱导表达。

2

OMVs的分离和表征

从培养上清中分离OMVs,并检测其大小、浓度及蛋白组成。

通过超滤和超速离心纯化OMVs,并用NTA分析粒径和浓度,SDS-PAGE和蛋白质组学分析蛋白组成。

3

ClyA-AR23蛋白的验证

确认ClyA-AR23蛋白在细胞和OMVs中的存在及表面暴露。

使用LC-MS/MS鉴定AR-23特异肽段,并使用ClyA-his蛋白进行Western blot、免疫荧光和蛋白酶K处理实验。

4

细胞毒性评估

评估OMVs对VERO-76细胞的毒性。

MTT法检测不同浓度OMVs处理细胞24小时后的存活率。

5

抗病毒活性检测

评估ClyA-AR23 OMVs对HSV-1、HSV-2、SARS-CoV-2及PV-1的抗病毒活性。

采用病毒预处理实验,蚀斑减少法计算抑制率,qPCR检测HSV-1 UL54基因表达。

研究方法

按研究目的归类文中使用的方法,便于定位所需技术。

产品清单

实验环节名称品牌货号
Luria-Bertani培养基----
异丙基β-D-1-硫代半乳糖苷Thermo-Fisher Scientific--
pET22b(+)载体Sigma-Merck--
T4 DNA连接酶New England Biolabs--
QIAprep质粒小提试剂盒Qiagen--
Amicon超滤装置----
NanoSight NS300Malvern Instruments--
胰蛋白酶/Lys-C混合物Promega--
Orbitrap Q-Exactive质谱仪Thermo-Fisher Scientific--
抗His标签多克隆抗体Elabscience--
抗OmpA单克隆抗体Antibody Research Corporation--
HRP标记的山羊抗兔IgGElabscience--
Excellent化学发光底物Elabscience--
AlexaFluor 488标记的山羊抗兔IgG----
TCS SP5共聚焦显微镜Leica MicroSystems--
MTTSigma-Aldrich--
DMEM培养基Gibco; Thermo Fisher Scientific--
胎牛血清Gibco; Thermo Fisher Scientific--
TRIzol试剂Thermo Fisher--
SensiFAST cDNA合成试剂盒Meridian Bioscience--
BrightGreen 2X qPCR预混液abm--
UNO96热循环仪VWR International--
GraphPad Prism 9.0软件GraphPad Software--

关键环节

汇总复现实验时建议重点确认的条件及原文阅读提示。

环节核对要点
重组蛋白表达
IPTG诱导浓度、温度、时间以及菌株类型。
阅读提示:参见Materials and Methods中的'ClyAhis and ClyA-AR23 recombinant expression'部分。
OMVs分离
超滤膜截留分子量、超速离心力、时间及温度。
阅读提示:参见Materials and Methods中的'OMVs isolation and purification'部分。
细胞毒性评估
细胞系(VERO-76)、处理浓度范围、处理时间、阳性及阴性对照。
阅读提示:参见Materials and Methods中的'Cytotoxicity of Escherichia coli OMVs'部分。
抗病毒活性检测
病毒株种类(HSV-1、HSV-2、SARS-CoV-2、PV-1)、OMVs浓度、预处理时间、MOI、感染时间、孵育时间。
阅读提示:参见Materials and Methods中的'Escherichia coli OMVs antiviral activity'部分。
qPCR
靶基因(UL54)、引物序列、内参基因(GAPDH)、退火温度、循环数。
阅读提示:参见Materials and Methods中的'qPCR of HSV-1 gene viral transcript UL54'部分。