Work

Optimizing genetic engineering approaches for protein loading into bacterial extracellular vesicles for vaginal drug delivery

Year: 2026

Type: article

Abstract: There is a critical gap in the development of new therapeutic platforms designed to treat gynecologic and obstetric diseases. Compared to systemic drug delivery, vaginal administration of nanoparticle formulations limits off-target side effects while increasing therapeutic concentration in target tissues, showing promise for clinical translation. However, these formulations suffer from limited scalability, high-cost reagents, and long optimization timelines. Recent work highlights the potential of bacterial extracellular vesicles (bEVs) as a low-cost, tunable platform for therapeutic applications. Here, we evaluate bEVs as a therapeutic carrier for vaginal drug delivery. We demonstrate the loading of the model protein moxNeonGreen into Escherichia coli Nissle 1917-derived bEVs. By optimizing growth parameters, we increase protein loading into bEVs. We evaluate the effect of bEVs on the vaginal microenvironment, and observe no negative impact on vaginal epithelial cells, endocervical cells, or vaginal bacteria in vitro. Additionally, we observe the retention of bEVs in the murine female reproductive tract for more than six hours. This study provides a framework for using genetically engineered bEVs to rapidly generate customizable therapies for a range of gynecologic and obstetric conditions, addressing longstanding challenges in women's health therapeutics. • Periplasmic localization of protein increases loading into bacterial extracellular vesicles. • Bacterial extracellular vesicles exhibit compatibility with female reproductive tract tissues both in vitro and in vivo. • Vaginally delivered E. coli -derived bacterial extracellular vesicles are retained in vivo for six hours.

Source: Journal of Controlled Release

DOI: 10.1016/j.jconrel.2026.114822