# Endothelial cell-assisted extracellular vesicle bioengineering for cytoplasmic delivery of therapeutic molecules

> **NIH NIH R21** · WASHINGTON UNIVERSITY · 2024 · $622,000

## Abstract

Project Summary
 Current paradigms of drug development have made remarkable progress in treating and
preventing disease by effecting the function of a single target enzyme, or receptor with
specificity. However, many chronic diseases like type 2 diabetes, Alzheimer’s disease, and
cardiovascular disease are multifaceted and may require alterations in multiple pathways, or
delivery to intracellular targets, to effectively treat the condition. For this reason, extracellular
vesicles (EVs) have gained attention as potential therapeutic carriers and endogenous
modulators of disease. EVs are nano-sized vesicles produced in all cells and carry
macromolecules that are capable of modulating multiple pathways simultaneously in the
receiving cell. Their cargo includes miRNAs, mRNA, DNA, signaling proteins, enzymes
metabolites and receptors. Mesenchymal stem cells (MSCs) have been extensively used as the
parent cells for therapeutic EVs as the cargo of these cells is broadly protective. Many groups
have engineered MSC EVs to carry therapeutic compounds through permeabilization techniques
which rely on passive diffusion of compounds into isolated EVs. However, the current
engineering techniques are exceptionally inefficient, which is a major factor in preventing the
translation of engineered EVs into the clinic.
 In this proposal we utilize vascular endothelial cells (ECs) to actively package desired
cargo into EVs. This is possible through a novel transcytosis-like process we recently published.
We found that ECs take up exogenous albumin-bound material from the cell culture media, load
the endocytosed material into newly formed EVs, and export those EVs at the basolateral side
of the cell. Interestingly, the released EVs seem to target specific cells in the tissue. Therefore,
we have designed experiments to test and optimize the capacity of ECs to load EVs with
exogenous albumin-bound miRNA, peptides, and drugs. We will test the therapeutic efficacy of
customized EVs in an in vitro and in vivo myocardial infarction mouse model system. We expect
that utilizing ECs will allow for extremely efficient, active loading of EVs, unmatched targeting to
the desired cell type and improved cargo offloading efficiency in receiving cells. This work has
the potential to transform the EV engineering field and bring us closer to clinically applicable EV-
based therapeutics.

## Key facts

- **NIH application ID:** 10866933
- **Project number:** 1R21EB035738-01
- **Recipient organization:** WASHINGTON UNIVERSITY
- **Principal Investigator:** Clair Crewe
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $622,000
- **Award type:** 1
- **Project period:** 2024-08-01 → 2027-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10866933

## Citation

> US National Institutes of Health, RePORTER application 10866933, Endothelial cell-assisted extracellular vesicle bioengineering for cytoplasmic delivery of therapeutic molecules (1R21EB035738-01). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10866933. Licensed CC0.

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