Assessing Deployment of Microbicidal Gels With Label-Free Optical Measurement

描述（由申请方提供）：本研究的目的是开发一种新的光学技术，用于测量应用于人类女性生殖道下部的抗HIV杀微生物制剂的分布。目前正在开发有希望的杀微生物剂，作为防治艾滋病和其他性传播感染的有力工具。然而，它们的适当部署对于实现预防至关重要。我们建议使用低相干干涉法（LCI）作为一种新的高分辨率，无标记的方法，用于阴道内测量杀微生物凝胶厚度，部署的中心特征。LCI在干涉测量方案中使用宽带光来实现具有几微米分辨率的深度分辨反射测量。初步测试表明，LCI是非常适合所提出的任务，通过展示凝胶厚度测量的精度和范围，满足或超过以前的方法用于此目的。此外，由于LCI可以在不使用外源性造影剂的情况下评估凝胶厚度，因此新的基于LCI的方法将允许更长时间的研究，因为避免了荧光标记的影响，例如光漂白和染料扩散。此外，基于LCI的方法将为更便宜，更强大的诊断系统提供更高的准确性和更容易的应用奠定基础。我们的长期目标是提供一种用于分析女性生殖道（和直肠）中杀微生物制剂部署的精辟，强大的临床仪器。该研究项目将确定为此目的使用基于LCI的诊断的可行性。我们提出以下具体目标：1。在当前原型的基础上，实施原型临床LCI系统。根据研究计划中的设计，当前LCI系统将适用于临床使用。新的原型将与目前用于女性临床研究的现有荧光系统集成。2.分析和比较集成系统与共同注册实验室在凝胶体模上进行体外试验的双重能力。将定义这两种技术的准确度和精密度。新系统的体外性能将在长时间范围内进行评估，在此期间，染料扩散和凝胶稀释限制了荧光方法的应用。3.在初步人体体内研究中测试集成系统。该方法的临床实用性将通过使用基于荧光和基于新LCI的技术联合测量三种凝胶（具有不同性质）的阴道涂层厚度分布来确定。在生物学相关实验设计中，将在凝胶插入后的短时间（10 min）和长时间（1 hr）绘制阴道涂层厚度，以实现一系列阴道涂层分布。因此，将完成使用LCI评估杀菌凝胶部署的原理验证的完整演示。该研究项目提出开发一种新的光学方法，用于评估女性生殖道中杀菌凝胶的部署。使用杀微生物凝胶可以有效预防性传播疾病的传播，但必须有效使用。本文提出的光学工具将允许比较杀微生物凝胶的各种制剂和部署策略，以及能够评估凝胶有效涂覆目标表面的时间量。

DESCRIPTION (provided by applicant): The objective of this research is to develop a new optical technique for measuring distributions of anti-HIV microbicidal formulations applied to the lower human female reproductive tract. Promising microbicidal agents are being developed as powerful tools for combating AIDS and other sexually transmitted infections. However their proper deployment is essential for achieving prophylaxis. We propose to use low coherence interferometry (LCI) as a new high resolution, label-free method for intravaginal measurements of microbicidal gel thickness, the central characteristic of deployment. LCI uses broadband light in an interferometry scheme to achieve depth resolved reflection measurements with a resolution of a few microns. Preliminary tests show that LCI is well suited to the proposed task by demonstrating gel thickness measurements with a precision and range that meets or exceeds those of previous methods employed for this purpose. Further, because LCI can assess gel thickness without using an exogenous contrast agent, the new LCI-based method will allow for longer time studies because effects seen with fluorescent tags, such as photobleaching and dye diffusion, are avoided. Moreover, the LCI-based method will form the basis for less-expensive, more robust diagnostic systems which provide higher accuracy and easier application. Our long range goal is to contribute an incisive, robust clinical instrument for analyzing the deployment of microbicidal formulations in the female reproductive tract (and rectum). This research project will establish the feasibility of using LCI-based diagnostics for that purpose. We propose the following Specific Aims: 1. Implement prototype clinical LCI system, building on the current prototype. The current LCI system will be adapted for clinical usage based on the design in the research plan. The new prototype will be integrated with an existing fluorescence-based system currently used for clinical studies in women. 2. Analyze and compare the dual capabilities of the integrated system with co- registered laboratory in vitro tests on gel phantoms. The accuracy and precision of the two techniques will be defined. The in vitro performance of the new system will be assessed over long time scales, during which dye diffusion and gel dilution limit application of the fluorometric approach. 3. Test the integrated system in preliminary human in vivo studies. The clinical utility of the approach will be established through joint measurements of vaginal coating thickness distributions of three gels (with different properties), using both the fluorescence-based and new LCI-based techniques. Vaginal coating thickness will be mapped at short (10 min) and longer (1 hr) times after gel insertion, in a biologically relevant experimental design that achieves a range of vaginal coating distributions. Thus, complete demonstration of the proof-of-principle of using LCI for assessing deployment of microbicidal gels will be accomplished. This research project proposes to develop a new optical method for assessing the deployment of microbicidal gels in the female reproductive tract. Effective prevention of the spread of sexually transmitted diseases can be accomplished using microbicidal gels however, they must be effectively deployed. The optical tool proposed here will allow the comparison of various formulations and deployment strategies of microbicidal gels as well as enabling assessment of the amount of time that a gel effectively coats the target surface.