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

March 17, 2013 (Bronx, NY) 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."


Contact: Kim Newman
Albert Einstein College of Medicine

Related biology news :

1. New research on migratory behavior of oceanic whitetip sharks can help shape conservation strategies
2. Its not just amyloid: White matter hyperintensities and Alzheimers disease
3. UGA researchers invent new material for warm-white LEDs
4. Majority of Americans doubt Congress and White House can avoid fiscal cliff
5. The smell of white
6. New ancient shark species gives insight into origin of great white
7. Whitehead scientists identify major flaw in standard approach to global gene expression analysis
8. A new technique to study how myeloids become white blood cells
9. Researchers use banker plants to help battle whitefly pests
10. Black belts white matter shows how a powerful punch comes from the brain
11. NOAA researchers see dramatic decline of endangered white abalone
Post Your Comments:
(Date:4/26/2016)... India and LONDON ... Infosys Finacle, part of EdgeVerve Systems, a product ... and Onegini today announced a partnership to integrate ... solutions.      (Logo: ... to provide their customers enhanced security to access ...
(Date:4/14/2016)... BioCatch ™, the global ... the appointment of Eyal Goldwerger as CEO. ... Goldwerger,s leadership appointment comes at a time of significant ... of its platform at several of the world,s largest ... unique cognitive and physiological factors, is a winner of ...
(Date:3/23/2016)... , March 23, 2016 ... erhöhter Sicherheit Gesichts- und Stimmerkennung mit Passwörtern ... (NASDAQ: MESG ), ein führender ... das Unternehmen mit SpeechPro zusammenarbeitet, um erstmals ... Finanzdienstleistungsbranche, wird die Möglichkeit angeboten, im Rahmen ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... SILVER SPRING, Md. , June 23, 2016 ... evidence collected from the crime scene to track the criminal ... sick, and the U.S. Food and Drug Administration (FDA) uses ... Sound far-fetched? It,s not. ... whole genome sequencing to support investigations of foodborne illnesses. Put ...
(Date:6/23/2016)... , June 23, 2016   EpiBiome , ... secured $1 million in debt financing from Silicon Valley ... up automation and to advance its drug development efforts, ... new facility. "SVB has been an incredible ... the services a traditional bank would provide," said Dr. ...
(Date:6/23/2016)... NEWPORT BEACH, Calif. , June 23, 2016 /PRNewswire/ ... offering new biological discoveries to the medical community, has ... and co-founder Matthew Nunez . "We ... provide us with the capital we need to meet ... funding will essentially provide us the runway to complete ...
(Date:6/23/2016)... ... June 23, 2016 , ... Velocity Products, a division ... tuned and optimized exclusively for Okuma CNC machining centers at The International Manufacturing ... collaboration among several companies with expertise in toolholding, cutting tools, machining dynamics and ...
Breaking Biology Technology: