Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.
Young source of kidney stem cells. Some of our organs, like our liver and gut have massive armies of stem cells that can replace and repair tissue. Other organs like our kidney have relatively few adult stem cells and are not very good at self repair. Now, a Belgian team has found a new source for plentiful kidney stem cells for research and possibly therapy, the urine of premature infants.
Because our kidneys don’t fully develop until about 34 weeks into pregnancy, premature infants retain bountiful kidney stem cells and shed them in their urine where they can be painlessly collected. The lead author on the study published in the Journal of the American Society of Nephrology, Fanny Oliveira Arcolino from the Katholieke Universiteit Leuven described the potential of these cells in a university press release posted by Medical News Today:
“Preterm neonatal progenitor cells might represent a powerful tool to be used in cell therapy and regeneration of damaged kidneys.”
She also noted that the first patients to benefit may be the pre-term infants themselves. They often have renal insufficiency and there may be a way to use these cells to boost their kidney function.
Fatty diets, over active stem cells, and cancer. While the kidney may have too few adult stem cells, sometimes it appears the gut can have too many and result in some beginning to form tumors. The long-seen link between high fat diets and certain cancers may turn out to be the result of that diet ratcheting up the production of gut stem cells.
“Our study for the first time showed the precise mechanisms of how a high-fat diet regulates intestinal stem-cell function and how this regulation contributes to tumor formation,” said Semir Beyaz the lead author from Harvard Medical School in a version of the widely printed story written by MSN.
In mice fed an extremely high fat diet, the researchers saw significant increases in gut stem cells as well as conversion of neighboring cells to ones that behave like stem stem cells, which began to divide and become tumors. There is no readily apparent pathway for scientists to use this knowledge to somehow let you eat a pound of bacon without guilt, but perhaps more impetus for moderation.
Add the breast to list of mini-organs. Over the past year or so researchers have announced a steady parade of miniature “organs” made in the laboratory that mimic the function of everything from the gut to the brain. A team at the Whitehead Institute in Cambridge, Massachusetts has added one that has been difficult to replicate, breast tissue.
With animal models of breast cancer routinely producing results that don’t pair well with what happens in humans, there has been a real need for functional three-dimensional breast tissue that can be used to study how different parts of the breast interact and react to potential therapies. Until now it has been difficult to keep breast tissue alive in the lab.
“I wouldn’t have thought it possible that these tissues could grow with such complexity and to such a size,” Piyush Gupta, a member of the team said in a press release used for a story by UPI. “It’s really quite remarkable.”
The researchers’ success came from a strategy similar to ones used by the creators of other mini-organs. They created an environment that more closely matched what the cells would find themselves in when in a person. They used a gel to give them a 3D structure and added some proteins and carbohydrates that would normally surround the cells. The stem cells seeded on to this structure produced all the various types of cells found in the breast, self-organized into ducts and those ducts produced material that is a precursor to milk—a very valuable tool for research.
A link to healthy cartilage. One federally approved therapy, several sanctioned clinical trials, and many unsanctioned clinics are striving to repair damaged joints by using stem cells to produce cartilage. Most of the unsanctioned clinics provide little or no data, and even when patients say the therapy seemed to help they often report that their “benefit” wears off after some months. The data from the sanctioned work has generally shown modest improvement at best.
This lack of dramatic results that many of us with aching knees would like to see comes in large part from our incomplete understanding of how stem cells and their intermediate cells produce healthy articular cartilage, the hard type you want in your knees not the soft kind found in your ear lobes. A team at Japan’s Okayama University and the National Institutes of Health in the US has identified a protein that seems to be a key trigger to get stem cells to form the chondrocytes needed to create articular cartilage. This protein, CCN4 could eventually become a sort of booster added to stem cell therapies for aching joints.
The researchers published their work in the journal Bone and HealthCanal posted a press release from the Japanese university.