With the power of self-renewal and multipotency, mesenchymal stem cells (MSCs) offer the possibility of regenerative treatment for a variety of medical conditions, including spinal cord injury and damage following a heart attack.
A leading hypothesis is that the therapeutic benefits of MSCs are conferred by their secretion of extracellular vesicles (EVs): membrane-derived structures that contain a variety of important bioactive molecules. Therapeutic cells like MSCs have variable EV production, contributing to inconsistent outcomes that hinder their clinical translation. Yet, scientists are unable to select cells based on their EV secretion levels.
“How do you know how many extracellular vesicles the [MSCs are] secreting? How do you know this batch of cells is better than this batch?” said Dino Di Carlo, a bioengineer at the University of California, Los Angeles.
In a new study published in Nature Communications, Di Carlo and his colleagues applied their expertise in microfluidics and nanotechnology to answer these questions. They developed a method to identify subpopulations of MSCs that secrete high levels of EVs, an approach that could allow for the selection of more therapeutically active cells for clinical applications.
Previously, Di Carlo and his team developed hydrogel-based microcontainers, which they called nanovials, that act as test tubes for single cells. By coating the inside of the bowl-shaped nanovials with antibodies that are specific to proteins released by a cell of interest, the researchers could capture individual cells and quantify their secretions. In an earlier study, the team used this technology to measure protein secretion from individual B cells, which they then linked to cell surface markers and gene expression data from the same cell.
By Rebecca Roberts, PhD
Article can be accessed on: The Scientist