Project Description

In recent decades, scientists have advanced various drug delivery modalities to overcome the blood-brain barrier (BBB), which excludes most neurotherapeutics from entering the central nervous system (CNS), in order to treat CNS disorders. The emerging brain virotherapy using AAV vectors was reported to be immunogenic and costly in manufacturing. In addition, it is rather perilous that therapeutic viruses have to be administered into cerebrospinal fluid. Hence, this year, our team aims to engineer HEK293T cells to produce engineered exosomes, which are extracellular vesicles naturally capable of traversing BBB, hereby providing a low-risk platform for CNS mRNA therapy . The engineering includes: 1. boosting the production of exosomes; 2. facilitating therapeutic RNA to be packaged into exosomes; 3. increasing targeting specificity to neurons with low leakage during the transport of RNA cargo 4. prolonging the expression of therapeutic RNAs in the neurons

Exosome biogenesis

This year, we decided to engineer human embryonic kidney cells (HEK293T) to produce engineered exosomes. we genetically modified HEK293T to increase the production of exosome.

RNA Packaging

Since exosomes have randomicity in substances packaging, we modified exosomes to be capable of packaging our designed therapeutic mRNA in larger amount. To achieve this goal, a RNA-protein interaction strategy was utilized.

Exosome delivery and targeting

Exosome is a kind of cell-derived vesicles with diameters between 30 nm ~100 nm and is naturally capable of passing the BBB. Our project involves three exosome device modification: RNA packaging, target cell characterization and exosome delivery.

RNA stabilization

Since exosomes have randomicity in substances packaging, we modified exosomes to be capable of packaging our designed therapeutic mRNA in larger amount. To achieve this goal, a RNA-protein interaction strategy was utilized.