Decoration of Outer Membrane Vesicles with Multiple Antigens by Using an Autotransporter Approach
Decoration of Outer Membrane Vesicles with Multiple Antigens by Using an Autotransporter Approach
复制标题
DOI：
10.1128/aem.01941-14
复制
发表时间：
2014-09-01
影响因子：
4.4
通讯作者：
Luirink, Joen
中科院分区：
文献类型：
--
作者：
Daleke-Schermerhorn, Maria H.;Felix, Tristan;Luirink, Joen
外膜囊泡（OMVs）是球形纳米颗粒，自然从革兰氏阴性细菌中脱落。它们富含免疫刺激蛋白和脂多糖，但不复制，这增加了它们的安全性，使它们成为有吸引力的疫苗载体。通过在omv中包装外源多肽，可以在固有佐剂的背景下对异源抗原产生特异性免疫反应。暴露在囊泡表面的抗原被认为比隐藏在OMV内的抗原具有更好的保护作用，但迄今为止还缺乏将异源蛋白靶向到OMV表面的可靠方法。我们已经利用我们之前开发的血红蛋白蛋白酶（Hbp）自动转运平台在OMV表面显示异种多肽。结核分枝杆菌抗原ESAT6、Ag85B和Rv2660c在与Hbp融合后被靶向到大肠杆菌omv表面。此外，制备了减毒肠炎沙门氏菌血清型鼠伤寒沙门氏菌SL3261的高泡化δ tolR δ tolA衍生物，能够高效释放和纯化带有多种异源抗原的omv，例如结核分枝杆菌抗原和沙眼衣原体主要外膜蛋白（MOMP）的表位。此外，我们还发现，在体外将显示Ag85B的沙门氏菌omv传递给抗原呈递细胞，会导致Ag85B特异性T细胞杂交瘤在功能上识别的表位的加工和呈递。综上所述，Hbp平台可以在omv表面有效地展示（多个）异源抗原，单个或组合在一个分子内。在囊泡介导的递送中检测抗原特异性免疫反应证明了我们的系统在疫苗开发方面的潜力。
Outer membrane vesicles (OMVs) are spherical nanoparticles that naturally shed from Gram-negative bacteria. They are rich in immunostimulatory proteins and lipopolysaccharide but do not replicate, which increases their safety profile and renders them attractive vaccine vectors. By packaging foreign polypeptides in OMVs, specific immune responses can be raised toward heterologous antigens in the context of an intrinsic adjuvant. Antigens exposed at the vesicle surface have been suggested to elicit protection superior to that from antigens concealed inside OMVs, but hitherto robust methods for targeting heterologous proteins to the OMV surface have been lacking. We have exploited our previously developed hemoglobin protease (Hbp) autotransporter platform for display of heterologous polypeptides at the OMV surface. One, two, or three of the Mycobacterium tuberculosis antigens ESAT6, Ag85B, and Rv2660c were targeted to the surface of Escherichia coli OMVs upon fusion to Hbp. Furthermore, a hypervesiculating Delta tolR Delta tolA derivative of attenuated Salmonella enterica serovar Typhimurium SL3261 was generated, enabling efficient release and purification of OMVs decorated with multiple heterologous antigens, exemplified by the M. tuberculosis antigens and epitopes from Chlamydia trachomatis major outer membrane protein (MOMP). Also, we showed that delivery of Salmonella OMVs displaying Ag85B to antigen-presenting cells in vitro results in processing and presentation of an epitope that is functionally recognized by Ag85B-specific T cell hybridomas. In conclusion, the Hbp platform mediates efficient display of (multiple) heterologous antigens, individually or combined within one molecule, at the surface of OMVs. Detection of antigen-specific immune responses upon vesicle-mediated delivery demonstrated the potential of our system for vaccine development.