Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

White blood cells found to play key role in controlling red blood cell levels

18.03.2013
Researchers at Albert Einstein College of Medicine of Yeshiva University and the Icahn School of Medicine at Mount Sinai have found that macrophages – white blood cells that play a key role in the immune response – also help to both produce and eliminate the body's red blood cells (RBCs).

The findings could lead to novel therapies for diseases or conditions in which the red blood cell production is thrown out of balance. The study, conducted in mice, is published today in the online edition of the journal Nature Medicine.

"Our findings offer intriguing new insights into how the body maintains a healthy balance of red blood cells," said study leader Paul Frenette, M.D., professor of medicine and of cell biology and director of the Ruth L. and David S. Gottesman Institute for Stem Cell and Regenerative Medicine Research at Einstein.

"We've shown that macrophages in the bone marrow and the spleen nurture the production of new red blood cells at the same time that they clear aging red blood cells from the circulation. This understanding may ultimately help us to devise new therapies for conditions that lead to abnormal RBC counts, such as hemolytic anemia, polycythemia vera, and acute blood loss, plus aid recovery from chemotherapy and bone marrow transplantation." Einstein has filed a joint patent application with Mount Sinai related to this research, which is currently available for licensing and further commercialization.

Previous studies, all done in the laboratory, had suggested that macrophages in the bone marrow act as nurse cells for erythroblasts, which are RBC precursors. But just how these "erythroblastic islands" (macrophages surrounded by erythroblasts) function in living animals was unclear.

A few years ago, Andrew Chow, a Mount Sinai M.D./Ph.D. student in the laboratories of Drs. Frenette, and Miriam Merad, M.D., Ph.D., professor of oncological sciences and immunology at Mount Sinai found that bone marrow macrophages express a cell surface molecule called sialoadhesin, or CD169 – a target that could be used for selectively eliminating macrophages from bone marrow. Doing so would help pinpoint the role of macrophages in erythroblastic islands in vivo.

That's what Drs. Frenette and Merad did in the current study involving mice. They found that selectively eliminating CD169-positive macrophages in mice reduces the number of bone marrow erythroblasts – evidence that these macrophages are indeed vital for the survival of erythroblasts, which develop into RBCs.

"What was surprising is that we couldn't see any significant anemia afterward," said Dr. Frenette. The researchers then analyzed the lifespan of the red blood cells and found that they were circulating for a longer time than usual.

"After we depleted the macrophages in the bone marrow, we discovered that we had also depleted CD169-positive macrophages present in the spleen and liver. It turns out that the macrophages in these two organs are quite important in removing old red blood cells from the peripheral circulation. Taken together, the findings show that these macrophages have a dual role, both producing and clearing red blood cells," he said.

The researchers also examined the role of macrophages in polycythemia vera, a genetic disease in which the bone marrow produces too many RBCs, typically leading to breathing difficulties, dizziness, excessive blood clotting and other symptoms. Using a mouse model of polycythemia vera, they found that depleting CD169-positive macrophages in bone marrow normalizes the RBC count. "This points to a new way to control polycythemia vera," said Dr. Frenette. "Right now, the standard of care is phlebotomy [periodic blood removal], which is cumbersome."

The title of the paper is “CD169+ macrophages provide a niche promoting erythropoiesis under homeostasis and stress.” The first author of the paper is Dr. Andrew Chow. Other co-authors of the study include Matthew Huggins, Daniel Lucas, Ph.D., Jalal Ahmed, B.S., Sandra Pinho, Ph.D., Yuya Kunisaki, M.D., Ph.D., and Aviv Bergman, Ph.D., of Einstein, and Daigo Hashimoto, M.D., Ph.D., Clara Noizat and Marylene Leboeuf of Mount Sinai, New York, NY. The study was done in collaboration with Nico van Rooijen at Vrije Universiteit, Amsterdam, The Netherlands; Masato Tanaka at RIKEN Research Center for Allergy and Immunology, Yokohama, Japan, and Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan; and Zhizhuang Joe Zhao, Ph.D., at University of Oklahoma Health Sciences Center, Oklahoma City, OK.

The study was supported by grants from the National Heart, Lung, and Blood Institute (R01 HL097700, R01HL069438, and R01HL116340); the National Institute of Diabetes and Digestive and Kidney Diseases (R01DK056638); and the National Cancer Institute (R01CA112100), all part of the National Institutes of Health.

Albert Einstein College of Medicine

Albert Einstein College of Medicine of Yeshiva University is one of the nation's premier centers for research, medical education and clinical investigation. In 2012, Einstein received over $160 million in awards from the NIH for major research centers at Einstein in diabetes, cancer, liver disease, and AIDS, as well as other areas. Through its affiliation with Montefiore Medical Center, the University Hospital for Einstein, and six other hospital systems, the College of Medicine runs one of the largest residency and fellowship training programs in the medical and dental professions in the United States. For more information, please visit http://www.einstein.yu.edu and follow us on Twitter @EinsteinMed.

Kim Newman | EurekAlert!
Further information:
http://www.einstein.yu.edu

Further reports about: Einstein RBC blood cell bone marrow cell biology red blood cells

More articles from Life Sciences:

nachricht What the world's tiniest 'monster truck' reveals
23.08.2017 | American Chemical Society

nachricht Treating arthritis with algae
23.08.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

What the world's tiniest 'monster truck' reveals

23.08.2017 | Life Sciences

Treating arthritis with algae

23.08.2017 | Life Sciences

Witnessing turbulent motion in the atmosphere of a distant star

23.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>