Department of Medicine, Beth Israel Deaconess Medical Center, Beth Israel Deaconess Medical Center, Boston, Massachusetts 02215, USA.
Antimicrob Agents Chemother. 2011 Dec;55(12):5547-52. doi: 10.1128/AAC.00509-11. Epub 2011 Sep 6.
Innovative methods of prevention are needed to stop the more than two million new HIV-1 infections annually, particularly in women. Local application of anti-HIV antibodies has been shown to be effective at preventing infection in nonhuman primates; however, the concentrations needed are cost prohibitive. Display of antibodies on a particulate platform will likely prolong effectiveness of these anti-HIV agents and lower the cost of goods. Here, we demonstrate that the bacterium Caulobacter crescentus and its highly expressed surface-layer (S-layer) protein can provide this antibody display platform. Caulobacters displaying protein G, alone or with CD4 codisplay, successfully captured HIV-1-specific antibodies and demonstrated functional neutralization. Compared to soluble antibodies, a neutralizing anti-HIV antibody displayed on Caulobacter was as effective or more effective at neutralizing diverse HIV-1 isolates. Moreover, when an antibody reactive with an epitope induced by CD4 binding (CD4i) was codisplayed with CD4, there was significant enhancement in HIV-1 neutralization. These results suggest that caulobacters displaying anti-HIV antibodies offer a distinct improvement in the use of antibodies as microbicides. Furthermore, these reagents can specifically evaluate anti-HIV antibodies in concert with other HIV-1 blocking agents to assess the most suitable tools for conversion to scFvs, allowing for direct display within the S-layer protein and further reducing cost of goods. In summary, C. crescentus, which can be easily produced and chemically stabilized at low cost, is well suited for engineering as an effective platform, offering an inexpensive way to produce and deliver HIV-1-specific microbicides.
需要创新的预防方法来阻止每年超过 200 万例新的 HIV-1 感染，尤其是在女性中。局部应用抗 HIV 抗体已被证明在非人类灵长类动物中能有效预防感染；然而，所需的浓度过高，成本难以承受。将抗体展示在颗粒平台上可能会延长这些抗 HIV 药物的效果，并降低商品成本。在这里，我们证明了新月柄杆菌及其高度表达的表面层（S 层）蛋白可以提供这种抗体展示平台。单独或与 CD4 共展示的表达蛋白 G 的新月柄杆菌成功捕获了 HIV-1 特异性抗体，并表现出功能中和。与可溶性抗体相比，在新月柄杆菌上展示的中和性抗 HIV 抗体在中和各种 HIV-1 分离株方面同样有效或更有效。此外，当与 CD4 结合诱导的表位（CD4i）反应的抗体与 CD4 共展示时，HIV-1 中和作用显著增强。这些结果表明，展示抗 HIV 抗体的新月柄杆菌在将抗体用作杀微生物剂方面提供了明显的改进。此外，这些试剂可以与其他 HIV-1 阻断剂一起特异性地评估抗 HIV 抗体，以评估最适合转化为 scFv 的工具，允许在 S 层蛋白内直接展示，并进一步降低商品成本。总之，新月柄杆菌可以低成本地生产和化学稳定，非常适合工程化作为一种有效的平台，为生产和提供 HIV-1 特异性杀微生物剂提供了一种廉价的方法。
