Scaffolds mimicking antigen presenting cells

目前体外扩增T细胞用于治疗应用的方法受到低扩增速率的限制 和功能有限的T细胞产物。为了解决这些问题，我们最近描述了一种系统， 模拟天然抗原呈递细胞（APC）。这些APC模拟物支架（APC-ms）由流体脂质组成， 由介孔二氧化硅微棒（MSRs）支撑的双层。脂质双层呈现膜结合的线索 用于T细胞受体刺激和预定密度的共刺激，而微棒能够持续 可溶性旁分泌信号的释放。使用抗CD 3、抗CD 28和白细胞介素-2的控释， 显示APC-ms促进原代小鼠和人T细胞的多克隆扩增10倍 比商业珠（Dynabeads）更好，并且可用于调节扩增的T细胞的表型属性。 产品. APC-ms还支持比Dynabeads高5倍以上的CD 19 CAR-T细胞扩增， 在临床相关的异种移植淋巴瘤模型中增加的功效。虽然APC-ms是一种有前途的T细胞， 扩展系统，有几个开发活动，将有助于其临床和商业 翻译.目前的MSR合成方法尚未针对该应用进行标准化，并且缺乏 建立了SOP，以生产具有一致特性的材料产品。目前，表面线索呈现 在APC-MS上使用生物素-链霉亲和素，但是使用点击化学代替链霉亲和素可以提供 优势的数量。而APC-ms被设计成在T细胞培养过程中完全降解 在这段时间内，避免了在细胞交付之前将其移除的需要，我们还没有彻底探讨其影响。 输注的T细胞产品上的任何潜在残留物质。这些需求导致了以下具体需求： 本项目的目标（1）建立APC-ms合成的SOP。这将包括确定MSR关键 功能性APC-ms的质量属性（CQA），并了解关键工艺参数（CPP） MSR合成影响那些CQA（2）开发直接和选择性地缀合表面线索的过程 通过点击化学作用，将APC-MS连接到脂质双层上，以简化APC-MS组装和功能的模块化。（三） 表征T细胞处理过程中残留的APC-ms材料，并进行全面的体内安全性评估 考核这些目标的成功实现将立即解决与使用 APC-ms作为离体T细胞扩增平台。

Current approaches to expand T cells ex vivo for therapeutic applications are limited by low expansion rates and T-cell products of limited functionality. To address these issues, we have recently described a system that mimics natural antigen-presenting cells (APCs). These APC-mimetic scaffolds (APC-ms) consist of a fluid lipid bilayer supported by mesoporous silica micro-rods (MSRs). The lipid bilayer presents membrane-bound cues for T-cell receptor stimulation and costimulation at predefined densities, while the micro-rods enable sustained release of soluble paracrine cues. Using anti-CD3, anti-CD28 and controlled release of interleukin-2, we have shown that the APC-ms promotes ten-fold greater polyclonal expansion of primary mouse and human T cells than commercial beads (Dynabeads), and can be used to tune the phenotypic attributes of expanded T-cell products. APC-ms also support over 5-fold greater expansion of CD19 CAR-T cells than Dynabeads, with increased efficacy in a clinically-relevant xenograft lymphoma model. While APC-ms is a promising T cell expansion system, there are several development activities that would aid its clinical and commercial translation. The current MSR synthesis process has not been standardized for this application, and lacks established SOPs to yield material products with consistent properties. Currently, surface cues are presented on APC-ms using biotin-streptavidin, but the use of click chemistry in place of streptavidin could provide a number of advantages. While APC-ms is designed to completely degrade during the process of T cell culture period, obviating the need for its removal before cell delivery, we have not yet thoroughly explored the impact of any potential residual materials on the infused T cell products. These needs lead to the following specific objectives for this project (1) Establish SOPs for APC-ms synthesis. This will include identifying MSR critical quality attributes (CQAs) for functional APC-ms and understanding how critical process parameters (CPPs) in MSR synthesis affect those CQAs (2) Develop a process to directly and selectively conjugate surface cues onto lipid bilayers, via click chemistry, to simplify and modularity of APC-ms assembly and function. (3) Characterize residual APC-ms materials during T cell processing, and perform a thorough in vivo safety assessment. The successful achievement of these aims will immediately address key issues related to using APC-ms as an ex vivo T-cell expansion platform.