Cell-engineered synthetic chylomicrons for oral drug delivery applications

生物药物如治疗性多肽和蛋白质的口服递送是一个重要的研究领域。然而，通过任何给药途径成功递送肽目前都极具挑战性。由于在胃肠道和肝脏中酶和pH介导的水解作用，多肽的低生物利用度（低吸收率和高首过萃取率）阻碍了口服递送。鉴于抗糖尿病肽和胰岛素样肽（如胰高血糖素样肽-1 (GLP-1)）的成功产生，由于患者的高依从性和市场潜力，人们对开发口服肽递送方法非常感兴趣。乳糜微粒是在肠细胞中通过新生的三酰甘油、胆固醇、胆固醇酯、至少一种脂溶性维生素和载脂蛋白B48 （ApoB48）的包装形成的脂蛋白（一组与血浆中脂肪或其他脂质结合并运输的可溶性蛋白质）。乳糜微粒从肠细胞分泌到肠系膜淋巴中。疏水分子和药物进入乳糜微粒可以利用这一途径将药物输送到淋巴管。在这个项目中，我们的目标是通过劫持和利用肠细胞中的乳糜微粒细胞机制，利用乳糜微粒实际上作为感兴趣的肽的隐形屏障，创造一种新的亲脂肽通过肠道传递的范例。通过将基于液滴的微流体与机器人技术相结合，我们将能够首次制造合成乳糜微粒（称为乳糜体），使我们能够系统地改变其组成并研究支撑其稳定性的分子相互作用。利用从这些研究中产生的分子工程规则，我们将设计可以搭载用户定义肽的新生乳糜微粒。利用器官芯片技术与超分辨率显微镜（纳米显微镜）相结合，我们将研究乳糜微粒与肠壁之间相互作用的机制。

The delivery of biological drugs such as therapeutic peptides and proteins via the oral route is an important area of research. However, successful peptide delivery via any administration route is currently highly challenging. The oral delivery of peptides is hampered due to their low bioavailability, which results from low absorption and high rates of first-pass extraction, due to enzymatic and pH mediated hydrolysis in the gastrointestinal (GI) tract and liver. Given the successful generation of antidiabetic peptides and insulin-like peptides (such as glucagon-like peptide-1 (GLP-1), there is great interest in developing oral peptide delivery methodologies due to high patient compliance and market potential. Chylomicrons are lipoproteins (a group of soluble proteins that combine with and transport fat or other lipids in the blood plasma) formed in enterocytes via the packaging of nascent triacylglycerols, cholesterol, cholesterol esters, at least one fat soluble vitamin, and apolipoprotein B48 (ApoB48). Chylomicrons are secreted from the enterocyte into the mesenteric lymph. Incorporation of hydrophobic molecules and drugs into chylomicrons can exploit this pathway for drug delivery to the lymphatics. In this project, we aim to create a new paradigm for lipophilic peptide delivery across the gut by hijacking and exploiting chylomicron cellular machinery in enterocytes with the chylomicrons in effect acting as stealth shields for the peptide of interest. By combining droplet-based microfluidics with robotics we will able to manufacture synthetic chylomicrons for the first time (termed chylosomes) enabling us to systematically vary their composition and study the molecular interactions that underpin their stability. Using the resulting molecular engineering rules that will emerge from these studies we will design de-novo chylomicrons that can onboard user-defined peptides. Using organon-a-chip technologies coupled with super-resolution microscopy (nanoscopy) we will then study the mechanism of interaction between the chylomicrons and the gut lining.