Aged bone marrow niche impedes function of rejuvenated hematopoietic stem cells
2021-04-13
(Press-News.org) Durham, NC - When leukemia strikes an older person, it is in part due to the aging of his or her hematopoietic stem cells (HSCs). These immature cells can develop into all types of blood cells, including white blood cells, red blood cells and platelets. As such, researchers have focused on rejuvenating HSCs as a way to treat leukemia.
A new study released today in STEM CELLS adds much to that level of knowledge by showing that the youthful function of rejuvenated HSCs upon transplantation depends in part on a young bone marrow "niche," which is the microenvironment surrounding stem cells that interacts with them to regulate their fate.
"The information revealed by our study tells us that the influence of this niche needs to be considered in approaches to rejuvenate old HSCs for treating aging-associated leukemia or immune remodeling," said Hartmut Geiger, Ph.D. He was senior author of the study, conducted by researchers at Ulm University (Germany) and Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
Old HSCs exhibit a reduced reconstitution potential and other negative aspects such as altered gene expression profiles and an increase in apolar distribution of proteins. (Polarity is believed to be particularly important to fate decisions on stem cell division and for maintaining an HSC's interaction with its niche. Consequently, a failure to establish or regulate stem cell polarity might result in disease or tissue deterioration.) Aging of HSCs might even affect lifespan.
Researchers already knew that increased activity of a protein called Cdc42, which controls cell division, leads to HSC aging, and that when old HSCs are treated ex vivo with CASIN, an inhibitor of Cdc42 activity, they stay rejuvenated upon transplantation into young recipients. The aim of this latest study was to learn what happens to these rejuvenated HSCs when they are transplanted into an aged niche.
To find out, Dr. Geiger and his team transplanted rejuvenated aged HSCs into three groups of mice: young (8 to 10 weeks old), old (19 to 24 months old) and young cytokine osteopontin (OPN) knockout mice (8 to 12 weeks old). The team had recently demonstrated that a decrease in the level of secreted OPN in the aged bone marrow niche confers hallmarks of aging on young HSCs, and also that secreted OPN regulates HSC polarity. Old HSC and rejuvenated old HSCs were therefore transplanted into the OPN knockout recipients to test whether a lack of this protein in the niche affects the function of old rejuvenated HSCs.
The results were then analyzed for up to 23 weeks after transplantation.
"They showed us that an aged niche restrains the function of ex vivo rejuvenated HSCs, which is at least in part linked to a low level of OPN found in aged niches," Dr. Geiger reported. "This tells us that in order to sustain the function of rejuvenated aged HSCs, we will likely need to address the influence of an aged niche on rejuvenated HSCs."
Dr. Jan Nolta, Editor-in-Chief of STEM CELLS, said, "this study is an elegant demonstration of the molecular mechanisms by which the marrow microenvironment controls cellular aging of hematopoietic stem cells. This new information will be extremely useful in the fields of transplantation and treatment of leukemia and other disorders of the blood-forming system."
INFORMATION:
The full article, "An aged bone marrow niche restrains rejuvenated hematopoietic stem cells," can be accessed at https://stemcellsjournals.onlinelibrary.wiley.com/doi/abs/10.1002/stem.3372.
About the Journal: STEM CELLS, a peer reviewed journal published monthly, provides a forum for prompt publication of original investigative papers and concise reviews. The journal covers all aspects of stem cells: embryonic stem cells/induced pluripotent stem cells; tissue-specific stem cells; cancer stem cells; the stem cell niche; stem cell epigenetics, genomics and proteomics; and translational and clinical research. STEM CELLS is co-published by AlphaMed Press and Wiley.
About AlphaMed Press: Established in 1983, AlphaMed Press with offices in Durham, NC, San Francisco, CA, and Belfast, Northern Ireland, publishes two other internationally renowned peer-reviewed journals: STEM CELLS®, celebrating its 39th year, is the world's first journal devoted to this fast paced field of research. The Oncologist®, also a monthly peer-reviewed publication, entering its 26th year, is devoted to community and hospital-based oncologists and physicians entrusted with cancer patient care. All three journals are premier periodicals with globally recognized editorial boards dedicated to advancing knowledge and education in their focused disciplines.
About Wiley: Wiley, a global company, helps people and organizations develop the skills and knowledge they need to succeed. Our online scientific, technical, medical and scholarly journals, combined with our digital learning, assessment and certification solutions, help universities, learned societies, businesses, governments and individuals increase the academic and professional impact of their work. For more than 200 years, we have delivered consistent performance to our stakeholders. The company's website can be accessed at http://www.wiley.com.
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
2021-04-13
Ancient clues, in the shape of fossils and archaeological evidence of varying quality scattered across Australia, have formed the basis of several hypotheses about the fate of megafauna that vanished about 42,000 years ago from the ancient continent of Sahul, comprising mainland Australia, Tasmania, New Guinea and neighbouring islands.
There is a growing consensus that multiple factors were at play, including climate change, the impact of people on the environment, and access to freshwater sources.
Now, research led by Professor Corey Bradshaw of Flinders University and the Australian Research Council Centre of Excellence of Australian Biodiversity and Heritage (CABAH) has used sophisticated mathematical modelling to assess how susceptible different species were to extinction - and what ...
2021-04-13
April 13th, 2021, Washington, D.C. - The severe health and economic impacts of the COVID-19 pandemic have disrupted food systems and upended livelihoods. Yet pandemic responses have demonstrated the power of well-crafted policies to blunt the impact of major shocks while laying the groundwork for stronger, more resilient food systems, according to the 2021 Global Food Policy Report, released today by the International Food Policy Research Institute (IFPRI). The report provides lessons drawn from the current crisis that can help us transform food systems to reduce the impact of the ongoing pandemic, better prepare for future shocks, and address longstanding weaknesses and inequalities.
"We have known ...
2021-04-13
In the early time of optical design, people have to be proficient in aberration theory and perform a huge amount of numerical calculations, and thus mathematical skills and talents are very important. The emergence of electronic computers has freed people from heavy calculation tasks, and realized fast real ray tracing and been able to solve complex aberration equations. Since then, the application and development of optimization algorithms and optical design software have greatly improved the speed and effect of optical design. However, optical design still requires to solve or find an initial solution as the starting point of optimization, which will greatly determine the final result of optimization. Moreover, optimization is essentially ...
2021-04-13
The top priority in the field of transplantation is to ensure that donor organs are allocated to the patients with the greatest need.
In a large-scale joint international project conducted by the Medical University of Vienna and the Mayo Clinic in Rochester (USA), researchers from the Department of General Surgery and the Division of Gastroenterology and Hepatology of MedUni Vienna's Department of Medicine III, have made a significant step forward to improve prediction of survival on the waiting list for liver transplantation by including additional laboratory parameters.
Donor ...
2021-04-13
In recent years the boom in streaming platforms and video on demand services has led to disruption in audiences, representing a difficulty when measuring the number of viewers of the content distributed by these platforms.
This new situation has not only altered the traditional television and film viewing model, but also has impacted the advertising market, which is a fundamental factor in funding and the business of audiovisual entertainment.
In this context, real and objective audience measurement (which is not influenced by the interests of the platforms) has become a key objective; it is fundamental to obtain real-time data on the reach of each production ...
2021-04-13
When trees die during a period of drought, they die of thirst. Researchers from the University of Basel have demonstrated in a field study that a rapid collapse in the hydraulic system is responsible for tree death. And they found out that the trees possibly die more rapidly than previously thought.
The heatwave of summer 2018 was an exceptional situation - both for nature and for research. Although admittedly hard on our native woods, it also presented an opportunity for researchers at the University of Basel to closely study the reaction of trees to this weather phenomenon.
The research group led by Professor Ansgar Kahmen had already set up a research area in the Basel-Landschaft municipality of Hölstein the previous year. Their aim was to study the tree ...
2021-04-13
Misinformation in public debates about scientific issues such as vaccinations and climate change can be found all over the internet, especially on social media. In a new study, Sara K. Yeo, associate professor of communication at the University of Utah, examines why it's so difficult to detect science misinformation and suggests that using humor may help combat the issue.
In the article, published in Proceedings of National Academics of Sciences, Yeo and her colleague Meaghan McKasy, assistant professor of communication at Utah Valley University, argue that limited science and media literacy combined with structural constraints such as fewer ...
2021-04-13
Low-dimensional colloidal quantum dots (CQD) have attracted significant attention because of their unique structures, extraordinary optical properties, and low-cost preparation processes. Since its first synthesis in the 1990s, motivation to realize high-performance low-cost CQD micro-/nanolasers have been a driving force for more than three decades. However, the low packing density, inefficient coupling of CQD with optical cavities, and the poor thermal stability of miniaturized complex systems make it challenging to achieve practical CQD micro-/nanolasers, especially to combine the continuous working ...
2021-04-13
Osaka, Japan - Fluorescence spectroscopy is indispensable in biomedical diagnostics. One can think of turning on fluorescence as turning on a flashlight in a dark room. A diagnostic assay can be designed to label, for example, a specific molecule of DNA with a fluorescent probe. If that specific molecule of DNA is present, you see fluorescence or a change in the fluorescence.
Sometimes an otherwise fluorescent molecule stops emitting light for a brief period of time. This is called fluorescence blinking, which can make it difficult to detect biomolecules at the ultralow concentrations ...
2021-04-13
Human blood contains several different components, including plasma, red blood cells (RBCs), white blood cells (WBCs), and platelets. Among these, WBCs are divided into numerous subcategories each with unique functions and characteristics, such as lymphocytes, monocytes, neutrophils, and others. Lymphocytes are further subdivided into T lymphocytes, B lymphocytes, and NK cells. Distinguishing and separating different types of these cells is highly important in carrying out studies in the field of immunology.
Discriminating different immune cell types is typically done by flow cytometry and fluorescence-activated cell sorting (FACS), which can identify distinct populations ...
LAST 30 PRESS RELEASES:
[Press-News.org] Aged bone marrow niche impedes function of rejuvenated hematopoietic stem cells
