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Human stem cell

Sílvia A Ferreira, Cristina Lopo and Eileen Gentleman, King’s College London

Download this image from Wellcome Collection.

A single human stem cell, which has a natural ability to repair damaged tissue and can divide to produce some of the different cells found in the body. This cell is sitting in a mixture of chemicals designed to mimic its natural environment inside the body, so that researchers can better understand how it interacts with its surroundings.

The stem cell is from inside the hip bone of a healthy person who donated some bone marrow to help treat patients who develop complications after receiving a marrow transplant.

The diameter of the cell is approximately 15 micrometres (0.015 mm).

Imaging technique: cryogenic scanning electron microscopy

The sample was first rapidly frozen at cryogenic temperatures (lower than −150°C or −238°F) to preserve it in its native, water-containing environment. Electrons were then bounced off the surface of the frozen sample to provide information on its structure. This information was used to create a greyscale replica of the cell, which was then digitally coloured.

Location where image was created

London, UK

Why did the judges choose this image?

“Amongst the many colourful electron micrographs that we had to judge this one was a refreshing surprise. This stem cell, from a healthy person’s bone marrow, looks like a nebula frozen in time at cryogenic temperatures despite having a diameter of only 0.015 mm. It also illustrates another characteristic of pictures produced with this type of technique: sharpness.”

Eric Hilaire, Science, Environment and Global Development Online Picture Editor at the Guardian

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