# Effects of Bovine Milk-Derived Extracellular Vesicles on a 3D Intestinal Stromal Compartment

## TL;DR

Bovine milk extracellular vesicles boost intestinal fibroblast growth and could help in tissue repair and artificial organ development.

## Contribution

This study is the first to show that bovine milk-derived extracellular vesicles enhance intestinal stromal fibroblast proliferation and bio-scaffold repopulation.

## Key findings

- MEVs stimulate fibroblast proliferation in a dose-dependent manner above 10^6 particles/mL.
- Pre-conditioning bio-scaffolds with MEVs enhances fibroblast growth and scaffold repopulation.
- MEVs may support intestinal tissue repair and development of serum-free 3D models.

## Abstract

What are the main findings?
Bovine milk-derived extracellular vesicles (MEVs) stimulate intestinal stromal fibroblast proliferation in a dose-dependent manner.Pre-conditioning three dimensional (3D) decellularized intestinal scaffolds with MEVs further boosts fibroblast growth and enhance bio-scaffold repopulation compared with conventional culture systems.

Bovine milk-derived extracellular vesicles (MEVs) stimulate intestinal stromal fibroblast proliferation in a dose-dependent manner.

Pre-conditioning three dimensional (3D) decellularized intestinal scaffolds with MEVs further boosts fibroblast growth and enhance bio-scaffold repopulation compared with conventional culture systems.

What are the implications of the main findings?
MEVs may play a significant role in intestinal tissue remodeling and repair by supporting stromal fibroblast function and gut homeostasis.MEVs may represent a noninvasive and readily available source of bioactive vesicles with potential application in the development of novel serum-free, chemically defined culture media for advanced 3D models and intestinal artificial organs.

MEVs may play a significant role in intestinal tissue remodeling and repair by supporting stromal fibroblast function and gut homeostasis.

MEVs may represent a noninvasive and readily available source of bioactive vesicles with potential application in the development of novel serum-free, chemically defined culture media for advanced 3D models and intestinal artificial organs.

Milk is an essential component of the diet. Among its diverse molecular constituents, it contains nanoscale entities, known as extracellular vesicles (EVs), which play a pivotal role in intercellular communication. In particular, milk-derived EVs (MEVs) influence intestinal homeostasis by mitigating inflammatory responses, modulating gut microbiota composition, and contributing to epithelial integrity preservation and restoration. Currently, there are no information regarding their impact on intestinal connective tissue. Here, we investigate bovine MEV effects on the porcine gut stromal compartment, exposing intestinal decellularized bio-scaffolds repopulated with primary intestinal stromal fibroblasts, to different MEV concentrations (106, 108, and 1010 particles/mL). We observed a dose-dependent effect of MEVs on stromal fibroblast proliferation rate at concentrations higher than 106 particles/mL. In addition, when MEVs were used to pre-condition the decellularized intestinal bio-scaffolds prior to cell repopulation, fibroblast growth was further boosted. Overall, these findings suggest that MEVs may play a significant role in promoting tissue remodeling and repair. This activity appears particularly relevant for enhancing intestinal homeostasis and resilience, as stromal fibroblasts contribute to the maintenance of gut integrity, barrier function, and immune balance. Moreover, the data here presented suggests the possibility of using MEVs to develop serum-free, chemically defined culture media for the generation of advanced three-dimensional (3D) models and intestinal artificial organs.