Featured Research

from universities, journals, and other organizations

Adults lack stem cells for making new eggs

Date:
April 29, 2013
Source:
Carnegie Institution
Summary:
Mammalian females ovulate periodically over their reproductive lifetimes, placing significant demands on their ovaries for egg production. Whether mammals generate new eggs in adulthood using stem cells has been a source of scientific controversy. If true, these "germ-line stem cells" might allow novel treatments for infertility and other diseases.

Mammalian females ovulate periodically over their reproductive lifetimes, placing significant demands on their ovaries for egg production. Whether mammals generate new eggs in adulthood using stem cells has been a source of scientific controversy. If true, these "germ-line stem cells" might allow novel treatments for infertility and other diseases. However, new research from Carnegie's Lei Lei and Allan Spradling demonstrates that adult mice do not use stem cells to produce new eggs.

Their work is published by the Proceedings of the National Academy of Sciences the week of April 29.

Before birth, mouse and human ovaries contain an abundant supply of germ cells, some of which will develop into the eggs that will ultimately be released from follicles during ovulation. Around the time of birth these germ cells have formed a large reserve of primordial follicles -- each containing a single immature egg. Evidence of new follicle production is absent after birth, so it has long been believed that the supply of follicles is fixed at birth and eventually runs out, leading to menopause.

During the last decade, some researchers have claimed that primordial follicles in adult mouse ovaries turn over and that females use adult germ-line stem cells to constantly resupply the follicle pool and sustain ovulation. These claims were based on subjective observations of ovarian tissue and on the behavior of extremely rare ovarian cells following extensive growth in tissue culture, a procedure that is capable of "reprogramming" cells.

Lei and Spradling used a technique that allows individual cells and their progeny within a living animal to be followed over time by marking the cells with a new gene. This general approach, known as lineage-tracing, has been a mainstay of classical developmental biology research and has greatly clarified knowledge of tissue stem cells during the last decade.

Their research showed that primordial follicles are highly stable, and that germ-line stem cell activity cannot be detected, even in response to the death of half the existing follicles. The research placed a stringent upper limit on the stem cell activity that could exist in the mouse ovary and escape detection--one stem cell division every two weeks, which is an insignificant level.

What about the rare stem-like cells generated in cultures of ovarian cells? According to Spradling, these cells "likely arise by dedifferentiation in culture," and "the same safety and reliability concerns would apply as to any laboratory-generated cell type that lacks a normal counterpart" in the body.


Story Source:

The above story is based on materials provided by Carnegie Institution. Note: Materials may be edited for content and length.


Journal Reference:

  1. Lei Lei and Allan C. Spradling. Female mice lack adult germ-line stem cells but sustain oogenesis using stable primordial follicles. PNAS, April 29, 2013 DOI: 10.1073/pnas.1306189110

Cite This Page:

Carnegie Institution. "Adults lack stem cells for making new eggs." ScienceDaily. ScienceDaily, 29 April 2013. <www.sciencedaily.com/releases/2013/04/130429154103.htm>.
Carnegie Institution. (2013, April 29). Adults lack stem cells for making new eggs. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2013/04/130429154103.htm
Carnegie Institution. "Adults lack stem cells for making new eggs." ScienceDaily. www.sciencedaily.com/releases/2013/04/130429154103.htm (accessed October 20, 2014).

Share This



More Health & Medicine News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Microneedle Patch Promises Painless Pricks

Microneedle Patch Promises Painless Pricks

Reuters - Innovations Video Online (Oct. 18, 2014) Researchers at The National University of Singapore have invented a new microneedle patch that could offer a faster and less painful delivery of drugs such as insulin and painkillers. Video provided by Reuters
Powered by NewsLook.com
Raw: Nurse Nina Pham Arrives in Maryland

Raw: Nurse Nina Pham Arrives in Maryland

AP (Oct. 17, 2014) The first nurse to be diagnosed with Ebola at a Dallas hospital walked down the stairs of an executive jet into an ambulance at an airport in Frederick, Maryland, on Thursday. Pham will be treated at the National Institutes of Health. (Oct. 16) Video provided by AP
Powered by NewsLook.com
Raw: Cruise Ship Returns to US Over Ebola Fears

Raw: Cruise Ship Returns to US Over Ebola Fears

AP (Oct. 17, 2014) A Caribbean cruise ship carrying a Dallas health care worker who is being monitored for signs of the Ebola virus is heading back to Texas, US, after being refused permission to dock in Cozumel, Mexico. (Oct. 17) Video provided by AP
Powered by NewsLook.com
Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

AFP (Oct. 17, 2014) All four suspected Ebola cases admitted to hospitals in Spain on Thursday have tested negative for the deadly virus in a first round of tests, the government said Friday. Duration: 00:55 Video provided by AFP
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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