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Having a Blast

Stem cell-derived model of early embryo development

21 May 2021

Having a Blast

In the first few days after sperm meets egg, the womb plays home to delicate cell divisions inside a blastocyst – the structure that will become an embryo. These fragile moments are vital to early pregnancy yet difficult to investigate. Instead, scientists grew this 'blastoid', an artificial blastocyst (right), using stems cells from inside a real blastocyst (left), pictured here under a high-powered microscope. Treating the stem cells with chemicals to switch genes on or off, researchers aim to guide their development in a similar way to real life. This blastoid is developing extraembryonic membranes similar to those which help to form the early placenta (highlighted in blue), as well as the yolk sac (purple, yellow). Scientists may now use blastoids as models for early developmental stages, investigating causes of miscarriage and other complications in fertility.

Written by John Ankers

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BPoD stands for Biomedical Picture of the Day. Managed by the MRC Laboratory of Medical Sciences until Jul 2023, it is now run independently by a dedicated team of scientists and writers. The website aims to engage everyone, young and old, in the wonders of biology, and its influence on medicine. The ever-growing archive of more than 4000 research images documents over a decade of progress. Explore the collection and see what you discover. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.

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