Featured Research

from universities, journals, and other organizations

Solution to platelet 'puzzle' uncovers blood disorder link

Date:
April 7, 2014
Source:
Walter and Eliza Hall Institute
Summary:
Researchers have solved a puzzle as to how an essential blood-making hormone stimulates production of the blood clotting cells known as platelets. The discovery has identified how bone marrow cells could become overstimulated and produce too many platelets. In blood diseases such as essential thrombocythemia, too many platelets can lead to clogging of the blood vessels, causing clots, heart attack or strokes.

Dr Ashley Ng and colleagues from the institute have solved a puzzle about how blood-making hormones stimulate the bone marrow to make platelets.
Credit: Image courtesy of Walter and Eliza Hall Institute

Melbourne researchers have solved a puzzle as to how an essential blood-making hormone stimulates production of the blood clotting cells known as platelets.

Platelets are essential for stopping bleeding and are produced by small fragments breaking off their 'parent' cells, called megakaryocytes.

The discovery, made by scientists at the Walter and Eliza Hall Institute, identified how bone marrow cells could become overstimulated and produce too many platelets. In blood diseases such as essential thrombocythemia, too many platelets can lead to clogging of the blood vessels, causing clots, heart attack or strokes.

Institute researchers Dr Ashley Ng, Dr Maria Kauppi, Professor Warren Alexander, Professor Don Metcalf and colleagues from the institute's Cancer and Haematology and Molecular Medicine divisions led the research, published in the journal Proceedings of the National Academy of Sciences.

Dr Ng said the hormone thrombopoietin was responsible for signalling bone marrow cells to produce platelets but, until now, researchers did not know precisely which cells responded to its signals. By studying the receptor for thrombopoietin, called Mpl, on blood cells in the bone marrow, the team pinpointed the cells involved in making platelets after thrombopoietin stimulation, and made an unexpected discovery.

"Thrombopoietin did not directly stimulate the platelet's 'parent' cells, the megakaryocytes, to make more platelets," Dr Ng said. "Thrombopoietin signals actually acted on stem cells and progenitor cells, several generations back."

To reach this conclusion, the researchers genetically removed the Mpl receptors from megakaryocytes and platelets. Dr Ng said the result was very surprising. "The progenitor and stem cells in the bone marrow began massively expanding and effectively turned the bone marrow into a megakaryocyte-making machine," he said.

"Our findings support a theory whereby megakaryocytes and platelets control platelet numbers by 'mopping up' excess amounts of thrombopoietin in the bone marrow. In fact, we show this 'mopping up' action is absolutely essential in preventing blood disease where too many megakaryocytes and platelets are produced."

The findings may have implications for human disease, Dr Ng said. "We know people with myeloproliferative disorders, such as essential thrombocythemia, produce too many megakaryocytes and platelets," he said.

"Interestingly, previous studies have shown megakaryocytes and platelets in people with essential thrombocythemia have fewer Mpl receptors, which fits our model for excessive platelet production. By using genetic 'signatures',we were able to compare the blood progenitor cells responsible for overproducing megakaryocytes in our model, to progenitor cells in people with essential thrombocythemia. We were able to show that progenitor cells in our model and in patients with essential thrombocythemia, had a signature of excessive thrombopoietin stimulation.

"We think this study now provides a comprehensive model of how thrombopoietin controls platelet production, and perhaps gives some insight into the biology and mechanism behind specific myeloproliferative disorders," Dr Ng said.


Story Source:

The above story is based on materials provided by Walter and Eliza Hall Institute. Note: Materials may be edited for content and length.


Journal Reference:

  1. A. P. Ng, M. Kauppi, D. Metcalf, C. D. Hyland, E. C. Josefsson, M. Lebois, J.-G. Zhang, T. M. Baldwin, L. Di Rago, D. J. Hilton, W. S. Alexander. Mpl expression on megakaryocytes and platelets is dispensable for thrombopoiesis but essential to prevent myeloproliferation. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1404354111

Cite This Page:

Walter and Eliza Hall Institute. "Solution to platelet 'puzzle' uncovers blood disorder link." ScienceDaily. ScienceDaily, 7 April 2014. <www.sciencedaily.com/releases/2014/04/140407153921.htm>.
Walter and Eliza Hall Institute. (2014, April 7). Solution to platelet 'puzzle' uncovers blood disorder link. ScienceDaily. Retrieved July 26, 2014 from www.sciencedaily.com/releases/2014/04/140407153921.htm
Walter and Eliza Hall Institute. "Solution to platelet 'puzzle' uncovers blood disorder link." ScienceDaily. www.sciencedaily.com/releases/2014/04/140407153921.htm (accessed July 26, 2014).

Share This




More Health & Medicine News

Saturday, July 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
Too Few Teens Receiving HPV Vaccination, CDC Says

Too Few Teens Receiving HPV Vaccination, CDC Says

Newsy (July 24, 2014) The Centers for Disease Control and Prevention is blaming doctors for the low number of children being vaccinated for HPV. Video provided by Newsy
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins