A tissue sample. Credit: Correa Lab
Researchers are one step closer to developing a gel that can be used to repair and regenerate tissue.
The team from Columbia University in the US has created an injectable hydrogel using a by-product of milk and yoghurt – extracellular vesicles (EVs).
Experiments in mice showed that within one week the yoghurt EV hydrogel promoted the formation of new blood vessels, a process known as angiogenesis which is required for effective tissue healing and regeneration.
“Being able to design a material that closely mimics the body’s natural environment while also speeding up the healing process opens a new world of possibilities for regenerative medicine,” says Artemis Margaronis, a graduate research fellow at Columbia Engineering.
Extracellular vesicles are tiny sacs that are secreted by cells and carry important materials like proteins, DNA and mRNA. EVs allow cells to communicate and transport complex materials, something scientists have found difficult to replicate in the lab.
The researchers used milk-derived EVs to create a hydrogel material by crosslinking large, biocompatible molecules known as polymers. This allowed the EVs to work as both a structural building block and a “bioactive cargo” transporting important materials.
The double role allowed the yoghurt EVs to mimic the mechanics of living tissue as well as engage the surrounding cells. This allowed them to promote healing and tissue regeneration without the need of any additional chemical additives, overcoming a main challenge to developing EV-based biomaterials.
“This project started as a basic question about how to build EV-based hydrogels. Yogurt EVs gave us a practical tool for that, but they turned out to be more than a model,” says Santiago Correa, who led the study.
“We found that they have inherent regenerative potential, which opens the door to new, accessible therapeutic materials.”
While current treatments often are unable to sustain long-term tissue repair, the researchers are hopeful this design could innovate wound treatment through regenerative medicine.
The injectable nature of the design also means that the hydrogel could be delivered locally to damaged tissue.
The mice in the experiment showed no signs of adverse reactions. The EVs also created an enriched anti-inflammatory cell immune response in the body, which may help with the tissue regeneration processes.
The research was a collaboration between Correa’s nanomaterial lab and researchers from the University of Padova, Italy who specialise in agricultural EV sourcing. The team is doing further research into the anti-inflammatory immune response in mice to understand how this gel can support tissue regeneration.
The study has been published in the journal Matter.