Researchers at the University of California, San Francisco announced an intriguing innovation on Monday. They call it “cell glue” and say it could one day open doors to tremendous medical advances, such as building organs in a transplant lab and reconstructing nerves damaged beyond the reach of standard surgical repair.
Essentially, the team constructed a series of synthetic molecules that can be manipulated to make cells in the human body connect to each other. Together these molecules form what is known as “cellular glue” and act like adhesive molecules that occur naturally in and around cells and involuntarily determine the way our tissues, nerves and organs are structured and anchored to one another.
Only in this case can scientists voluntarily control them.
“The properties of a tissue, such as your skin, are determined in large part by how the different cells within it are organized,” says Adam Stevens, a researcher at UCSF’s Cell Design Institute and first author of an article in the journal Nature in a statement. “We are developing ways to control this organization of cells, which is central to being able to synthesize tissues with the desired properties.”
Doctors could eventually use the sticky material as a viable mechanism to heal patients’ wounds, regrow nerves otherwise thought to have been destroyed, and possibly even work toward the regeneration of diseased lungs, livers, and other vital organs.
That last bit could help ease the crisis of donor organs, which are fast running out. According to the Health Resources and Services Administration, 17 people die every day in the US while on the organ transplant waiting list, yet every 10 minutes one more person is added to the list.
“Our work reveals a flexible molecular code of adhesion that determines which cells interact in which way,” Stevens said. “Now that we’re starting to understand it, we can use this code to control how cells assemble into tissues and organs.”
Essentially, immediately after babies are born (and even while they’re still in the womb), if a bond is lost, their cells find it easy to reconnect with each other. This is mainly because children are still growing, so their cells are still actively coming together. But that’s also why their scratches and scrapes heal pretty quickly.
In other words, think of children’s cell molecules as a set of well-defined instructions on how to assemble them to form tissues, organs, and nerves. They’re like sentient little Ikea furniture with the store’s build booklet in hand.
However, as people get older, these biological Ikea how-to guides end up in the attic, the team explains. That’s because the body is pretty solid for the most part – and that’s sometimes a problem. For example, if someone’s liver is really damaged, their liver cell molecules may need to refer to those Ikea instructions but can’t find them.
But this is where “cell glue” molecules come into play. These saviors can essentially be prepped using these Ikea instructions before being sent into the body, so their blueprint is fresh. Scientists can load them with information about which cell molecules to bind to and even how strongly to bind to them.
These adhesive molecules can then bring relevant cells together and thus support the healing and regeneration process.
“In a solid organ, like a lung or a liver, many of the cells are quite tightly connected,” explains a UCSF description of the new invention. “But in the immune system, weaker bonds allow cells to flow through blood vessels or crawl between tightly bound cells of skin or organ tissues to reach a pathogen or wound.”
To enable this type of adaptation, the researchers added two important components to their cell glue. First, part of the molecule acts as a receptor. It stays outside the cell and determines which other cells the molecule is allowed to interact with. Second, there’s the Bond strength tuner. This section exists inside the cell. Combine and tailor these two properties, and you can create a series of cell adhesion molecules primed to connect in different ways, the team says.
“We were able to engineer cells so that we can control which cells they interact with and also control the nature of that interaction,” said Wendell Lim, director of UCSF’s Cell Design Institute and senior author of the paper statements.
In fact, the team says the range of potential molecules is wide enough to impact the academic phase of medical school as well. For example, researchers could create mock tissues to deepen the understanding of the human body as a whole.
Or as Stevens put it, “These tools could be really transformative.”