Bacteriophage MS2 Virus-Like Particles for Peptide Display

描述(申请人提供)：噬菌体展示是一种非常强大和通用的技术，能够从大量随机产生的多肽序列中选择新的结合功能。从一个足够复杂的文库中，可以通过亲和选择从物理上分离出具有几乎任何所需结合活性的噬菌体多肽，并且由于每个颗粒在其基因组中携带用于其自身复制的遗传信息，因此可以在细菌中扩增选择物。本项目的目的是开发一种新的在RNA噬菌体MS2的病毒样颗粒(VLP)上展示多肽的平台。我们设想了MS2VLP的几种应用，但我们希望特别强调它在疫苗开发中的作用。它将把VLP的强大免疫原性和常规噬菌体展示的亲和力选择能力整合到一个单一平台中。丝状噬菌体是目前应用最广泛的噬菌体展示载体，为表位鉴定提供了有效手段。然而，它们所展示的多肽通常免疫原性很差，因为它们通常不支持形成密集的重复阵列。同时，其他VLP系统允许对特定的预选表位进行工程展示，但不能展示多肽库和亲和力选择。我们认为MS2VLP将克服这些限制。显示在MS2 VLP上的多肽具有很强的免疫原性，可以被改造成包裹编码它们的相同的mRNA分子，从而能够通过RT-PCR恢复亲和力选择的序列。此外，MS2 VLP的结构和组装相对简单，使得在体外进行整个迭代选择/扩增过程成为可能。这可以使实现高度的库复杂性变得更容易，并且应该使自动化成为可能。公共卫生相关性：该项目旨在利用MS2噬菌体的病毒样颗粒开发一种新的多肽展示平台。人们设想了几种应用，但由于它们具有强大的免疫原性，这些颗粒应该对疫苗发现特别有用。

DESCRIPTION (provided by applicant): Phage display is an extraordinarily powerful and versatile technology that enables the selection of novel binding functions from large populations of randomly generated peptide sequences. From a sufficiently complex library, phage bearing peptides with practically any desired binding activity can be physically isolated by affinity selection, and, since each particle carries in its genome the genetic information for its own replication, the selectants can be amplified in bacteria. This aim of this project is to develop a new platform for peptide display on virus-like particles (VLPs) of the RNA bacteriophage MS2. We envision several applications for the MS2 VLP, but we wish especially to emphasize its utility for vaccine development. It will integrate into a single platform the potent immunogenicity of a VLP with the affinity selection capability of conventional phage display. Filamentous phages are now the most widely used vehicles for phage display, and provide an efficient means for epitope identification. However, the peptides they display are typically poorly immunogenic, because they do not normally support the formation of dense repetitive arrays. Meanwhile, other VLP systems permit engineered display of specfic pre-selected epitopes, but are incapable of peptide library display and affinity selection. We think MS2 VLPs will overcome these limitations. Peptides displayed on MS2 VLPs are strongly immunogenic, and can be engineered to encapsidate the same mRNA molecule that encodes them, thus enabling recovery of affinity selected sequences by RT-PCR. Further, the comparative simplicity of MS2 VLP structure and assembly makes it possible to conduct the entire iterative selection/amplification process in vitro. This could make it easier to achieve high library complexities, and should make automation possible. PUBLIC HEALTH RELEVANCE: This project aims to develop a new platform for peptide display using virus-like particles of bacteriophage MS2. Several applications are envisioned, but because of their potent immunogenicity, these particles should be especially useful for vaccine discovery.