Trehalose significantly enhances the recovery of serum and serum exosomal miRNA from a paper-based matrix

CRISPR-Cas9 Engineered Extracellular Vesicles for the Treatment of Dominant Progressive Hearing Loss

Clinical translation of gene therapy has been challenging, due to limitations in current delivery vehicles such as traditional viral vectors. Herein, we report the use of gRNA:Cas9 ribonucleoprotein (RNP) complexes engineered extracellular vesicles (EVs) for in vivo gene therapy. By leveraging a novel high-throughput microfluidic droplet-based electroporation system (μDES), we achieved 10-fold enhancement of loading efficiency and more than 1000-fold increase in processing throughput on loading RNP complexes into EVs (RNP-EVs), compared with conventional bulk electroporation. The flow-through droplets serve as enormous bioreactors for offering millisecond pulsed, low-voltage electroporation in a continuous-flow and scalable manner, which minimizes the Joule heating influence and surface alteration to retain natural EV stability and integrity. In the Shaker-1 mouse model of dominant progressive hearing loss, we demonstrated the effective delivery of RNP-EVs into inner ear hair cells, with a clear reduction of Myo7ash1 mRNA expression compared to RNP-loaded lipid-like nanoparticles (RNP-LNPs), leading to significant hearing recovery measured by auditory brainstem responses (ABR).

How does temperature play a role in the storage of extracellular vesicles?

Extracellular vesicles (EVs) contain specific proteins, lipids, and nucleic acids that can be passed to other cells as signal molecules to alter their function. However, there are many problems and challenges in the conversion and clinical application of EVs. Storage and protection of EVs is one of the issues that need further research. To adapt to potential clinical applications, this type of problem must be solved. This review summarizes the storage practices of EVs in recent years, and explains the impact of temperature on the quality and stability of EVs during storage based on current research, and explains the potential mechanisms involved in this effect as much as possible.

Isolation of extracellular vesicles from intestinal tissue in a mouse model of intestinal ischemia/reperfusion injury

Extracellular vesicles (EVs) are small membranous particles that contribute to intercellular communications. Separating EVs from tissue is still a technical challenge. Here, we present a rigorous method for extracting EVs from intestinal tissue in a mouse intestinal ischemia/reperfusion (I/R) model, and for analyzing their miRNA content. The isolated EVs show a typical cup shape with a size peak of 120-130 nm in diameter, confirmed by TEM and NTA. They also express EV markers such as CD9, CD63, CD81, Tsg101 and Alix. Real-time qPCR confirmed that these pellets contain miRNAs related to I/R injury. Our study presents a practical way to isolate EVs from intestinal tissue which is suitable for downstream applications such as miRNA analysis, and provides a novel method for investigating the mechanism of intestinal I/R injury.

3D microdevices that perform sample purification and multiplex qRT-PCR for early cancer detection with confirmation of specific RNAs

MicroRNA expression analysis is an important screening tool for the early detection of cancer. In this study, we developed two portable three-dimensional microdevices for multiple singleplex RNA expression analysis by microRNA purification and qRT-PCR as a prototype for point-of-care testing. These microdevices are composed of several types of modules termed 'chemical IC chips'. We successfully reduced the heating area and fluorescence observation area, reduced the energy required for the reaction, and improved the portability of all systems in the devices. The purification microdevice could purify the microRNA from the sample using the FTA elute card system. The disposable reactor module mounted on both devices was easily fabricated by deforming a 100-μm-thick polypropylene film using an uncomplicated procedure. The qRT-PCR microdevice could perform reactions for samples of small volume. We purified microRNA from the HepG2 liver cancer cell line using the purification microdevice and confirmed the expression level of miR-224, which is a potential biomarker for liver cancer. Furthermore, we observed an increase in the fluorescence intensity when we performed qRT-PCR in the qRT-PCR microdevice. Therefore, the two developed microdevices show promise as a new portable tool for early cancer detection.