New Injectable Therapy May Support Brain Recovery and Repair After Stroke: Study - Video

A new injectable material may help the brain repair itself after an ischemic stroke, according to a study in mice by researchers at Duke University.

Published in Cell Biomaterials, the study looked at a special scaffold designed to fill the space left behind when a stroke destroys brain tissue. The goal was to create a better environment where the body could begin repairing the damaged area.

The researchers used a material called microporous annealed particle, or MAPS, made from tiny hydrogel particles. These particles form a sponge-like structure with spaces that cells can enter.

The researchers added extracellular vesicles, or EVs, released by brain cells called astrocytes. EVs are tiny packages that carry signals capable of changing how nearby cells behave.

The team found that combining two signalling molecules, IL-4 and C1q, helped attract immune cells to the damaged area. These included macrophages and neutrophils.

Neutrophils are usually associated with inflammation after a stroke. However, the study suggests that, at a later stage, they may also help with tissue repair when they receive the right signals. When researchers reduced these neutrophils, the formation of new blood vessels and changes in the scaffold were reduced.

The treated mice also developed more blood vessels and more axons, which are parts of nerve cells that help transmit signals. These changes were linked to better movement. After eight weeks, the treated mice performed similarly to healthy mice on a test that measured how accurately they placed their front paws while walking.

The scaffold itself appeared to be important. EVs given without the MAPS material did not produce the same level of blood-vessel repair.

However, this treatment is still at an early experimental stage. It has only been tested in mice, so researchers need to study its safety and effectiveness in larger animals before considering human trials.

REFERENCE: Shangjing Xin, et al.; IL-4/C1q activated astrocyte-derived extracellular vesicles promote stroke infarct recovery by recruiting peripheral leukocytes. Cell Biomaterials, 2026; 100543 DOI: 10.1016/j.celbio.2026.100543