A Microfluidics-Based Scalable Approach to Generate Extracellular Vesicles with Enhanced Therapeutic MicroRNA Loading for Intranasal Delivery to Mouse Glioblastomas

Abstract

Extracellular vesicles (EVs), including exosomes and microvesicles derived from different cell sources, are used as promising nanovesicles for delivering therapeutic microRNAs (miRNAs) and drugs in cancer therapy. However, their clinical translation is limited by the quantity, size heterogeneity, and drug or small RNA loading efficiency. Herein, we developed a scalable microfluidic platform that can load therapeutic miRNAs (antimiRNA-21 and miRNA-100) and drugs while controlling the size of microfluidically processed EVs (mpEVs) using a pressure-based disruption and reconstitution process. We prepared mpEVs of optimal size using microvesicles isolated from neural stem cells engineered to overexpress CXCR4 receptor and characterized them for charge and miRNA loading efficiency. Since the delivery of therapeutic miRNAs to brain cancer is limited by the blood-brain barrier (BBB), we adopted intranasal administration of miRNA-loaded CXCR4-engineered mpEVs in orthotopic GBM mouse models and observed a consistent pattern of mpEVs trafficking across the nasal epithelia, bypassing the BBB into the intracranial compartment. In addition, the CXCR4-engineered mpEVs manifested selective tropism toward GBMs by stromal-derived factor-1 chemotaxis to deliver their miRNA cargo. The delivered miRNAs sensitized GBM cells to temozolomide, resulting in prominent tumor regression, and improved the overall survival of mice. A simple and efficient approach of packaging miRNAs in mpEVs using microfluidics, combined with a noninvasive nose-to-brain delivery route presents far-reaching potential opportunities to improve GBM therapy in clinical practice.

Intranasal Delivery of Functionalized Polymeric Nanomaterials to the Brain

“…Lately, various therapeutic nanovehicles that are based on exosomes, [ 64,180–187 ] mesenchymal stem cells, [ 188,189 ] and neural stem cells [ 124,190,191 ] have been employed for IN delivery to the CNS. For instance, the GNP‐labeled exosomes were designed to be used for in vivo neuroimaging by Betzer et al.…”

Dynamic Intercell Communication between Glioblastoma and Microenvironment through Extracellular Vesicles

“…Therefore, an alternative approach is gravely needed. Compared to synthetic polymers, virus-based vectors or lipids EVs have higher delivery efficiency and better biocompatibility, making them promising nanocarriers [ 73 ]. Due to the small size and presence of the surface molecules, they have high tissue affinity and natural target capacity, and consequently less of the undesired off-target effects [ 30 ].…”

Functionalized Nanomaterials as Tailored Theranostic Agents in Brain Imaging

“…However, the treatment choices depend on various aspects, such as type of glioma, location, stage, and their size, in the patient survival rate, which could predict the intranasal drug delivery and treatments. Past reports found that tumors pre-sensitized with therapeutic miRNAs could show rapid reduction in tumor volumes upon chemotherapy and facilitate imaging functions upon treatment with engineered nanomaterials for intranasal delivery [ 51 , 68 ]. Novel approaches to bypass the physical barriers and challenges to cognitive disease treatments are always dependent on finding alternative ways for the direct route to the brain.…”

“…To address this issue, Wang et.al. recently showed that the extracellular vesicles (EVs) of various cells could be used as a potential carrier to load therapeutic miRNAs against glioblastoma in a microfluidic platform for potential IN delivery [ 68 ]. This study proved that the delivery of EVs targeting CXCR4-SDF1α receptor axis in the orthotopic glioblastoma models enhances the delivery of loaded miRNAs via bypassing the BBBs of the mice intracranial compartments in vivo.…”

“…One of the factors that needs to be respected is the role of transporters of drug influx and efflux transporters; hence, new drugs must be studied concerning their ability to be removed by these efflux transporters or if it is possible to use specific inhibitors that may improve the therapeutic and imaging efficacy by altering the pharmacokinetic profile of drugs in the brain following intranasal or intraolfactory administration of nanomaterials. Taken together, research and development in the field of intranasal or intraolfactory drug administration by nanomaterials is a rapidly growing area in brain drug delivery [ 68 , 75 , 105 ]. In addition, newer nanomaterials in theranostics will demand innovation in therapeutic targets in the brain, where more specific delivery systems need to be developed.…”