New analysis exhibits a tiny, regenerative worm might change our understanding of therapeutic

Stowers scientists uncover new guidelines about how flatworm stem cells regrow physique elements, providing insights into potential tissue restore and regenerative drugs in people.

KANSAS CITY, Mo., Oct. 15, 2025 /PRNewswire/ — Stem cells in most organisms sometimes take cues from adjoining cells. But new analysis from the Stowers Institute for Medical Research reveals planarian stem cells ignore their nearest neighbors and as a substitute reply to alerts additional away within the physique. This discovery could assist clarify the flatworm’s extraordinary means to regenerate — and will provide clues for creating new methods to interchange or restore tissues in people.

The study, revealed in Cell Reports on October 15, 2025, and led by Postdoctoral Research Associate Frederick “Biff” Mann, Ph.D., from the lab of Stowers President and Chief Scientific Officer Alejandro Sánchez Alvarado, Ph.D., challenges the textbook idea that the majority stem cells reside in a hard and fast, bodily place referred to as a distinct segment, the place surrounding cells inform them when or when to not divide and what to grow to be.

“For instance, human blood-forming stem cells reside in niches within bone marrow where they divide to self-renew and make new blood cells,” mentioned Mann.

The workforce, nevertheless, revealed that the planarian’s outstanding means to regrow physique elements, for instance, rebuilding an amputated head and even a whole physique from only a tiny fragment, is linked to stem cells that act extra independently from their environment than these in most different animals.

“Understanding how stem cells are regulated in living organisms is one of the great challenges in the fields of stem cell biology and regenerative medicine,” mentioned Sánchez Alvarado. “This finding challenges our concept of a stem cell ‘niche’ and may significantly advance our understanding of how to control stem cells’ abilities to restore damaged tissues.”

Adult planarian stem cells have limitless potential to grow to be any kind of cell, in distinction to most different organisms together with people whose stem cells are tightly regulated to allow them to provide just some specialised cell sorts. Part of this management system is in place to assist forestall unchecked cell progress, which is a trademark of most cancers. 

“Our hope is to uncover the basic rules that guide stem cells to become specific tissues as opposed to going rogue, as most tumors in humans begin when stem cells stop following these rules,” mentioned Sánchez Alvarado.

“The role of a traditional niche may be more in line with a micromanager — instructing cells, ‘You can be a stem cell, but only one particular type’,” mentioned Mann. “However, we’ve now shown having a normal niche may not be essential for stem cells to work. Some stem cells, like those in the planarian flatworm, have figured out a way to be independent and can turn into any type of cell without needing a nearby niche.”

Armed with the rising expertise of spatial transcriptomics, the researchers might decide which genes are turned on not simply inside one cell but in addition inside surrounding cells in a tissue. This revealed shocking neighbors — notable styles of cell sorts that encompass stem cells. The most distinguished was one not beforehand characterised — a really massive cell with a mess of projections, or fingerlike extensions of its cell membrane. The workforce named these cells “hecatonoblasts” after Hecatoncheires, a Greek mythological monster with many arms.

“Because they were located so close to stem cells, we were surprised to find that hecatonoblasts were not controlling their fate nor function, which is counterintuitive to a typical stem cell-niche connection,” mentioned Mann.

Instead, the workforce found the strongest directions got here from intestinal cells — the following most distinguished cell kind of their dataset. They discovered these cells have been certainly offering planarian stem cells with directions concerning their place and performance throughout regeneration, regardless of being a substantial distance away.

“I tend to think about this as local versus global communication networks,” mentioned co-corresponding creator Blair Benham-Pyle, Ph.D., an Assistant Professor on the Baylor College of Medicine in Houston, Texas, and former Stowers Postdoctoral Research Associate. “While interactions between stem cells and their neighboring cells influence how a stem cell reacts immediately, distant interactions may control how that same stem cell responds to big changes in an organism.” 

The workforce found that planarian stem cells appear to be uncoupled from conventional contact-based niches and “found that there isn’t a specific cell type or factor right next to stem cells that is controlling their identity,” mentioned Benham-Pyle. Thus, they hypothesize that this can be the important thing underlying planarian stem cell efficiency, and the unimaginable regenerative feats flatworms can carry out.

“The big discovery is a property of the whole planarian permitting both subtle local interactions and global signaling events that allow stem cells to achieve these remarkable feats of regeneration,” mentioned Benham-Pyle.

“The most surprising finding is that, at least in planarians, the environment in which the stem cells reside is not fixed. Instead, it’s dynamic — where stem cells reside is essentially made up by ‘friends’ that the stem cells and their progeny make along the way to differentiation,” mentioned Sánchez Alvarado. “The more we understand how nearby cells and overall signals in the body work together to boost the ability and power of our stem cells, the better we’ll be at creating ways to improve the body’s natural healing. This knowledge could help develop new treatments and regenerative therapies for humans in the future.”

Additional authors embody Carolyn Brewster, Ph.D., Dung Vuu, Riley Galton, Ph.D., Enya Dewars, Mol Mir, Carlos Guerrero-Hern ández, Jason Morrison, Mary KcKinney, Ph.D., Lucinda Maddera, Kate Hall, Seth Malloy, Shiyuan Chen, Brian Slaughter, Ph.D., Sean McKinney, Ph.D., Stephanie Nowotarski, Ph.D., and Anoja Perera.

This work was funded by the National Institute for General Medical Sciences of the National Institutes of Health (NIH) (award: R37GM057260) and by institutional assist from the Stowers Institute for Medical Research. The content material is solely the duty of the authors and doesn’t essentially symbolize the official views of the NIH.

About the Stowers Institute for Medical Research

Founded in 1994 via the generosity of Jim Stowers, founding father of American Century Investments, and his spouse, Virginia, the Stowers Institute for Medical Research is a non-profit, biomedical analysis group with a concentrate on foundational analysis. Its mission is to increase our understanding of the secrets and techniques of life and enhance life’s high quality via revolutionary approaches to the causes, therapy, and prevention of ailments.

The Institute consists of 20 impartial analysis packages. Of the roughly 500 members, over 370 are scientific employees that embody principal investigators, expertise heart administrators, postdoctoral scientists, graduate college students, and technical assist employees. Learn extra in regards to the Institute at www.stowers.org and about its graduate program at www.stowers.org/gradschool.

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SOURCE Stowers Institute for Medical Research