Scientists in Belgium have discovered how to clone human embryos from eggs that have been matured in the laboratory. Their discovery should make it easier for scientists to create embryonic stem cell lines from cloned embryos and develop them to provide eggs and sperm for infertile couples, the 21st annual conference of the European Society of Human Reproduction and Embryology heard today (Monday 20 June).
Until now, scientists investigating human cloning for therapeutic purposes have been limited to using mature eggs (oocytes) that have reached the metaphase II stage (MII) at which ovulation and fertilisation occurs in humans. However, there are few human MII oocytes available for research because almost all that are retrieved from women seeking fertility treatment are used to treat the patient. Immature oocytes are not used routinely for treatment at present, and so any that are retrieved can be donated for research. These immature oocytes are arrested in the prophase I stage, before meiotic division is complete, when the enlarged nucleus is called the germinal vesicle (GV).
Bjorn Heindryckx, a PhD student at the Infertility Centre at Ghent University Hospital, Belgium, and his colleagues, matured GV oocytes in culture in the laboratory for 44 hours, after which time 85% of the GV oocytes had developed into MII oocytes. From each of these, they removed the nuclear apparatus, which contained the chromosomes that held all the genetic information. Using conventional ICSI techniques, they injected into the empty oocytes the nuclei taken from somatic cumulus1 cells (i.e. non-germ cells) of another person – a process known as non-autologous nuclear transfer. After time for nuclear re-programming the oocytes were artificially activated by incubation in a medium containing calcium ionophore, which enabled the injected nucleus to prepare for the first embryonic division.
Emma Mason | alfa
Scientists unlock ability to generate new sensory hair cells
22.02.2017 | Brigham and Women's Hospital
New insights into the information processing of motor neurons
22.02.2017 | Max Planck Florida Institute for Neuroscience
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
22.02.2017 | Power and Electrical Engineering
22.02.2017 | Life Sciences
22.02.2017 | Physics and Astronomy