Scalable production of recombinant protein microbicides

描述（由申请人提供）：HIV杀微生物剂设计用于性交前局部应用，以抑制病毒并预防感染。一些最有希望的杀微生物剂候选物是蛋白质，但是它们的临床开发和评估受到缺乏可用材料和/或必须非常便宜地制造大量重组蛋白质的前景的阻碍。植物生物技术提供了一些潜在的解决方案。虽然以农业规模生产杀微生物剂是一个长期目标，但第一代产品很可能将在更可识别为传统药物生产系统的条件下，从在密闭环境中生长的植物中产生。长期以来已经确定重组蛋白可以在植物的所有组织（包括根）中表达。事实上，由转基因植物产生的一些重组蛋白在称为根分泌的过程中从根系主动分泌。这使得转基因植物可以在温室中使用确定的培养基在水培条件下生长。此外，杀微生物剂产品可以从水培培养基而不是植物组织中收获，这将大大简化纯化，并允许在植物的整个生命周期中收获。植物的水培栽培已经是园艺工业中的成熟技术，并且目前也用于生产天然药用化合物。本提案的目的是建立一种用于生产两种杀微生物剂蛋白候选物氰威菌素-N和单克隆抗体4 E10的包含的水培烟草植物培养方法，并制定生长和生产的优化策略，以提供以前不可用的蛋白质杀微生物剂，使其达到临床评价的水平。我们将建立小规模的商业生产。在该提案的第一阶段（R21），我们打算证明该方法的可行性，并为进入第二阶段（R33）建立了生产驱动的里程碑，在第二阶段，我们将根据良好实践监管要求开发生产和纯化，最终为临床试验提供蛋白质杀微生物剂。Cyanovirin-N和MAb 4 E10是目前可用的两种最有前途的蛋白质杀微生物剂候选物。然而，这两种药物的临床开发都受到生产困难的阻碍，其疗效和安全性仍有待确定。该项目旨在开发CV-N、MAb 4 E10和最终其他重组蛋白杀微生物剂的生产平台，将这些产品推向人体临床试验。

DESCRIPTION (provided by applicant): HIV microbicides are designed to be applied topically before sexual intercourse to inactivate the virus and prevent infection. Some of the most promising microbicide candidates have been proteins, but their clinical development and evaluation has been hampered by the lack of available material and/or the prospect of having to manufacture vast quantities of recombinant protein very cheaply. Plant biotechnology offers some potential solutions. Whilst the production of microbicides at agricultural scale is a long term aim, it is likely that the first generation products will emerge from plants grown in containment, under conditions more recognizable as conventional medicine production systems. It has long been established that recombinant proteins can be expressed in all tissues of the plant, including roots. Indeed, some recombinant proteins produced by transgenic plants are actively secreted from the root system in a process known as rhizosecretion. This gives rise to the possibility that transgenic plants could be grown in greenhouses under hydroponic conditions, using a defined culture medium. Moreover, the microbicide product could be harvested from hydroponic culture medium, rather than plant tissue, which would greatly simplify purification, and allow harvest over the lifetime of the plant. Hydroponic cultivation of plants is already a well established technique in the horticultural industry and is also currently used for the production of natural medicinal compounds. The objective of this proposal is to establish a contained hydroponic tobacco plant culture approach for production of two microbicide protein candidates, cyanovirin-N and MAb 4E10, and to develop optimization strategies for growth and production that will deliver previously unavailable protein microbicides at a level to allow clinical evaluation. We will establish production at small commercial scale. In the first (R21) phase of the proposal, we intend to demonstrate feasibility of the approach and have established production driven milestones for entry into the second (R33) phase, in which we will develop manufacturing and purification according to Good Practice regulatory requirements ultimately to deliver protein microbicides for clinical trials. Cyanovirin-N and MAb 4E10 are two of the most promising protein microbicide candidates currently available. However, the clinical development of both has been held back by production difficulties, and their efficacy and safety profiles are still to be determined. This project is aimed at developing a production platform for CV-N, MAb 4E10 and ultimately other recombinant protein microbicides, that will advance these products to human clinical trials.