Research Roundup: Rejuvenating Brain Cells, Curing HIV, and Bacteria That Eat Pollution
There are plenty of great scientific research stories out this week. Here’s a look at just a few of them.
Rejuvenating Brain Cells in Mice
Researchers from the Luxembourg Centre for Systems Biomedicine (LCSB) of the University of Luxembourg and from the German Cancer Research Center (DKFZ) rejuvenated stem cells in the brains of aging mice. These stem cells resulted in the improvement of injured or diseased areas in the brain. They published the research in the journal Cell.
“Our results constitute an important step towards the implementation of stem cell-based therapies, for instance for neurodegenerative diseases,” stated Antonio del Sol, head of the LCSB’s Computational Biology Group. “We were able to show that, with computational models, it is possible to identify the essential features that are characteristic of a specific state of stem cells.”
The group created a new computational model, which determines which proteins are responsible for the functional state of a given stem cell in its niche. This allows the researchers to identify whether a stem cell will divide or stay quiescent. It is built on which genes are being transcribed. The group’s research identified a molecule called sFRP5 that keeps neuronal stem cells inactive in old mice, and blocks the Wnt pathway, which is crucial for cell differentiation. By neutralizing the sFRP5, quiescent stem cells started proliferating more actively, which let them be recruited for regeneration processes in the aging brain.
Lifting Weights Can Improve Cancer Treatment
Scientists from Osaka University in Japan found that sarcopenia, which is marked by decreased skeletal muscle mass, is associated with poor treatment outcomes in lung cancer patients receiving PD-1-inhibitor therapy. These therapies rely on the patient’s immune system, but the team found that better skeletal muscle mass—which can be increased with pumping iron—had a more positive effect on PD-1-i treatments. Their research was published in the journal Scientific Reports.
“Sarcopenia is a well-known risk factor associated with poor outcomes for several cancer types,” stated lead author Takayuki Shiroyama. “Because muscle degradation is associated with a dysregulated immune response, we wanted to investigate how, in lung cancer patients, sarcopenia impacts the efficacy of PD-1 inhibitor therapy.”
The results showed that 38.1 percent of non-sarcopenia patients were in remission one year after treatment, while only 10.1 percent of sarcopenia patients had no sign of tumor progression. The researchers aren’t specifically saying cancer patients should go out and lift weights or all that gym time will improve lung cancer treatments. Shiroyama does note, however, “Our findings suggest that baseline skeletal muscle mass has a substantial impact on PD-1 inhibitor efficacy. As such, skeletal muscle mass might be useful for predicting whether treatment is likely to be effective.”
2nd Patient Potentially Cured of HIV
Researchers have described a second person globally to be cleared of HIV, the virus that causes AIDS. The first patient was Timothy Ray Brown, also dubbed the “Berlin Patient,” who was cured of HIV in 2007. The new study was published in the journal Nature. The new patient, who remains unnamed, is dubbed the “London Patient.”
Both Timothy Brown and the new patient were treated with stem cell transplants from donors carrying a rare genetic mutation called CCR5-delta 32. This made these patients resistant to HIV. The new patient has been in remission for 18 months after he stopped receiving antiretroviral drugs.
“By achieving remission in a second patient using a similar approach, we have shown that the Berlin Patient was not an anomaly and that it really was the treatment approaches that eliminated HIV in these two people,” said Ravindra Gupta, lead author of the study and a researcher at the Division of Infection and Immunity at the University College London (UCL), reported CNN.
The London Patient will be continued to be monitored. Gupta indicates that it is too early to declare he has been cured of HIV. Gupta also notes that the method used is not appropriate for all patients. However, it does offer new hope for HIV patients and the potential of adding new treatment strategies, including gene therapies.
New Stage of Fetal Development Discovered
“Being able to follow the differentiation process of every cell is the Holy Grail of developmental biology,” stated Qiaolin Deng, researcher in the Department of Physiology and Pharmacology, Karolinska Institutet, who led the research. She went on to say, “Knowledge of the events and factors that govern the development of the early embryo is indispensable for understanding miscarriages and congenital disease. Around three in every 100 babies are born with fetal malformation caused by faulty cellular differentiation.”
The new stage is between the attachment of the embryo to the uterus and the development of the first anatomical axis. It is at that point where the embryonic cells begin to create a body, with a front and a back. The developmental states of the cells involved in the process are not always the same. The researchers used single-cell RNA sequencing on 1,724 cells from 28 mouse embryos in four early stages of development. An average of 8,577 genes were expressed in each cell. They then sorted the cells into different cell types based on whether they were inactive or active. This led to a molecular roadmap of events controlling cell differentiation.
Kidney Tubules Grown on Chips
Researchers from the Hubrecht Institute, the University of Utrecht, and Mimetas have grown kidney tubules from human kidney adult stem cells in microfluidic chips. The research was published in the journal Nature Biotechnology. What they grew were three-dimensional epithelial organoids—kidney tubular epithelial organoids—also called tubuloids. They were established from human and mouse kidney tissue.
“Scientists at the Hubrecht Institute managed to reprogram stem cells found in the human kidney cortex to cells that are similar to tubular cells of the kidney,” stated Henrietta Lanz, director of Biology at MIMETAS and co-author of the paper. “From these cells, my team has grown three-dimensional perfused kidney tubules. We have discovered that these tubules are fully polarized, meaning that they distinguish inside from outside, just like in a real kidney.”
She went on to say, “Moreover, the biologically important barrier function of the kidney tubes is intact. We show that transporter activity is functional, which is a hallmark of kidney tissue, responsible for pumping of nutrients and toxicants across the kidney barrier. We can grow 40 of such tubules in one single OrganoPlate. The kidney tubes can be used to create disease models that allow the development of novel therapies.”
Bacteria that Eat Pollution and Breathe Electricity
Famously, Taq polymerase, a thermostable DNA polymerase that is the basis of the polymerase chain reaction (PCR), which made modern biotechnology possible, was isolated from a strain of bacterium, T. aquaticus, found in the hot springs at Yellowstone National Park.
Now, researchers with Washington State University have isolated bacteria from Yellowstone hot springs that appear to eat certain types of toxic pollutants and convert it into electricity. They published their research in the Journal of Power Sources. These types of bacteria have been enriched and isolated in research labs, but this is the first time they were enriched and isolated in their native environment.
To do so, the researchers developed a low-cost, battery-operated potentiostat, which they tested in four alkaline hot springs in Heart Lake Geyser Basin in Yellowstone. The springs have temperatures ranging from 45°C to 91°C (about 110 to 200 degrees F) and a relatively constant pH of 8.5-8.7. They left the electrodes in the edge of the water for 32 days, returning to collect them.
“This was the first time such bacteria were collected in situ in an extreme environment like an alkaline hot spring,” stated Abdelrhman Mohamed, a graduate student at WSU working under the supervision of Haluk Beyenal along with postdoctoral researcher Phuc Ha.
Beyenal stated, “As these bacteria pass their electrons into metals or other solid surfaces, they can produce a stream of electricity that can be used for low-power applications.”
Most organisms, including humans, get electrons from sugars in the food we eat and pass them into the oxygen we breathe. These types of bacteria pass their electrons to outside metals or minerals. Who knows? Maybe they can be modified or grown in substantial enough quantities to “eat” toxic metals and produce electricity.