Researchers loaded milk-derived extracellular vesicles with the antimicrobial peptide LL37 and an anti-TNF-α nanobody using a cell-penetrating peptide, creating an oral treatment that alleviated both acute and chronic ulcerative colitis in mice.
Oral delivery survived GI tractThe TAT cell-penetrating peptide enabled loading of biologics into milk vesicles that protected them from gastrointestinal degradation, enabling effective oral delivery to the colon.
What the researchers found
The cell-penetrating peptide TAT enabled efficient loading of biologic drugs into milk-derived extracellular vesicles (EVs) and protected them from degradation in the gastrointestinal tract both in vitro and in vivo.
Oral delivery of EVs loaded with the anti-TNF-α nanobody VHHm3F (EVVHH) significantly reduced tissue TNF-α levels and alleviated pathology in mice with acute ulcerative colitis, outperforming the nanobody delivered alone. In chronic UC, EVs simultaneously loaded with both VHH and the antimicrobial peptide LL37 (EVLV) improved the intestinal barrier, reduced inflammation, rebalanced the gut microbiota, and relieved UC-induced depression and anxiety. The TAT-mediated loading approach was described as simple and generalizable to other diseases.
Why it matters
Current biologic treatments for IBD typically require injection and cannot be taken orally because they are destroyed in the gut. This study demonstrates a practical oral delivery system using naturally occurring milk vesicles that are safe, scalable, and can carry multiple therapeutic agents simultaneously. The combination of anti-inflammatory and antimicrobial peptide payloads addresses both hallmarks of UC — inflammation and dysbiosis — in a single oral formulation.
How the study worked
The researchers engineered milk-derived extracellular vesicles by fusing a cell-penetrating peptide (TAT) to cargo proteins to enable loading. They tested protection against gastrointestinal degradation in vitro and in vivo. Acute UC was modeled in mice to test EVVHH, measuring tissue TNF-α and pathology. Chronic UC was modeled to test the dual-loaded EVLV formulation, assessing intestinal barrier function, inflammation, microbiota composition, and behavioral symptoms (depression/anxiety).
What this study cannot tell us
All experiments were conducted in mice, and the complexity of human UC — including its chronic relapsing nature and heterogeneous presentation — may not be fully captured by murine models. The scalability and consistency of milk-derived EV production for clinical use is not addressed. Long-term safety of repeated oral EV administration is unknown. The behavioral improvements (anxiety/depression) were measured in mouse models with limited translatability to human neuropsychiatric symptoms.
How to read the evidence
This is a preclinical study using mouse models of both acute and chronic ulcerative colitis. The multi-component approach (TAT loading, dual cargo, acute + chronic models, behavioral endpoints) is thorough for preclinical work, but no human safety or efficacy data exist for this platform.
When this study was published
Published in 2024, this is very recent research in the rapidly evolving field of extracellular vesicle therapeutics. The approach is novel and has not yet been tested in humans.
The bigger picture
This study sits at the intersection of three active research fields: extracellular vesicle therapeutics, antimicrobial peptide therapy, and oral biologic delivery. Milk-derived EVs are particularly attractive because milk is abundant, safe, and the vesicles have natural stability in the gut. If this approach translates to humans, it could transform IBD treatment by replacing injected biologics with oral formulations — a major improvement in patient quality of life and treatment adherence.
Questions still open
- Can this milk-derived EV delivery system be scaled to pharmaceutical-grade production while maintaining consistent loading efficiency and biological activity?
- Would the dual EVLV formulation be effective in human UC, where the disease is more complex and variable than in mouse models?
- Could this TAT-mediated EV loading platform deliver other peptide or biologic drugs orally for conditions beyond UC?
Common questions
What are milk-derived extracellular vesicles and why use them for drug delivery?
What is LL37 and what does it do in this treatment?
Read the original research
Milk-derived extracellular vesicles functionalized with anti-tumour necrosis factor-α nanobody and anti-microbial peptide alleviate ulcerative colitis in mice.
Journal of extracellular vesicles, 13(6), e12462
Citation
Jing, Renwei; Zhang, Leijie; Li, Ruibin; Yang, Zhongqiu; Song, Jun; Wang, Qian; Cao, Nan; Han, Gang; Yin, HaiFang. (2024). Milk-derived extracellular vesicles functionalized with anti-tumour necrosis factor-α nanobody and anti-microbial peptide alleviate ulcerative colitis in mice.. Journal of extracellular vesicles, 13(6), e12462. https://doi.org/10.1002/jev2.12462