The Fertility Show, Manchester Central, 23-24 March 2019
Page URL: https://www.bionews.org.uk/page_92507

New method to create mature egg cells discovered

9 August 2010
Appeared in BioNews 570

Immature mouse eggs have been successfully matured and fertilised in the laboratory for the first time. Eggs from women undergoing cancer therapy were also successfully matured using the new method, offering hope for some women suffering infertility such as cancer patients made infertile by treatment.

Until now, fertility treatments have matured eggs at a relatively late stage in development when they are less numerous and harder to access. But the new method, termed 'in vitro activation' (IVA) stimulates ovarian follicles - the structures encasing immature egg cells - earlier when they are still dormant.

Professor Aaron Hsueh, senior author of the study, said the technique: 'holds the promise of expanding the options for women seeking treatment for infertility', particularly those who have no or too few eggs.

To generate the mature eggs, an ovary from three-day-old mice was treated with a chemical inhibitor of PTEN - an enzyme which keeps the early follicles in an inactive state - along with 740Y-P, an activating substance. After two days, most of the follicles were activated. The follicles were transferred to adult mice and follicle stimulating hormone (FSH) was given daily.

Two weeks later, the treated ovaries were visibly larger, heavier and contained up to six times more advanced follicles than the untreated ones. Twenty healthy mouse pups were born after the mature eggs were fertilised and 118 embryos transplanted into adult female mice.

The same PTEN-blocking chemical was used to treat immature eggs in human ovarian tissue, which was transplanted into host mice. After six months, the tissue contained a much higher percentage of advanced follicles or mature eggs than the untreated tissues. But the human eggs weren't fertilised and the authors were careful to point out much more work is required before the technique can be used in humans.

The researchers, led by Dr Jing Li at Stanford University, California, published their findings online in the journal Proceedings of the National Academy of Sciences (PNAS). The study was funded by National Institutes of Health (NIH).

SOURCES & REFERENCES
Activation of dormant ovarian follicles to generate mature eggs
PNAS |  1 June 2010
NIH-Funded Researchers Generate Mature Egg Cells From Early Ovarian Follicles
NIH News |  4 August 2010
RELATED ARTICLES FROM THE BIONEWS ARCHIVE
21 March 2011 - by Rosemary Paxman 
Progesterone released from an egg may help guide sperm towards it and assist sperm to penetrate the egg's protective layers, according two studies published in Nature...
20 December 2010 - by Dr Lux Fatimathas 
US researchers have shown a correlation between human egg quality and blood bisphenol A (BPA) levels. In a small-scale study women with higher blood BPA levels showed...
2 November 2009 - by Dr Rebecca Robey 
US scientists have succeeded in creating early-stage sperm and egg cells from human embryonic stem cells (ES cells). By studying these artificially created sperm and eggs, the research team have identified three key genes that are involved in the development of these cells. The findings, published in the journal Nature, may one day lead to a cure for some causes of infertility....
2 July 2003 - by BioNews 
BioNews reporting from ESHRE conference, Madrid: A study presented at the annual conference of the European Society of Human Reproduction and Embryology conference in Madrid, Spain, has suggested a future way of harvesting eggs from aborted fetuses. Researchers from Israel and the Netherlands presented the results of a preliminary study...
5 August 2002 - by BioNews 
A team of Japanese scientists has successfully matured mouse eggs in the laboratory, opening up the possibility of preserving the fertility of young female cancer sufferers. The research team, led by Izuho Hatada, took very early eggs from mouse fetuses and were able to mature them and use them to...
29 November 1999 - by BioNews 
A Canadian team has achieved high maturation and pregnancy rates by using eggs matured in vitro with a group of 40 women undergoing in vitro fertilisation (IVF). The group, from McGill University and the Royal Victoria Hospital in Montreal, reported that from 45 cycles of the new procedure, 15 clinical...
HAVE YOUR SAY
Log in to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions


Syndicate this story - click here to enquire about using this story.