Name: Caleb Dawson
Picture title: Breast Alveoli in Lactation
Category: Micro
Nationality: Australian
Occupation: Medical researcher

Caleb says:
‘During pregnancy and lactation, the tree-like breast ducts bloom to form spherical alveoli – the sites where milk is produced. Each alveolus contains many milk-producing cells that are encircled by tiny muscle-like cells, revealed here by yellow and purple dyes. The muscle-like cells contract in response to suckling to push the milk from the alveoli, into the ducts and to the infant.

I captured this image while studying how the breast interacts with the immune system. Through images like this, our team was able to find a new type of immune cell in the breast that watches over the ducts and alveoli and keeps them healthy by removing dying cells.

Getting to this final image is a very elaborate process: staining specific cells with fluorescent dyes, making the tissue transparent, scanning with a microscope, then creating a final 3D rendering.

I used a confocal microscope that removes out of focus light with a very small pinhole. This lets the microscope detect sharp fluorescence in a single optical plane that is 0.5µm thick. I set up the microscope to scan through the tissue, capturing image stacks that are tiled and stitched together to cover an area almost 1mm across.’

Technical information:
Zeiss 880 confocal microscope
Zeiss x40 1.2NA oil DIC objective
Technique: 3D fluorescence confocal
Magnification: x40, tiled
Post processing: Imaris for 3D rendering and capturing the original image. Photoshop for cropping, removing background signal and lighting.

Website: calebadawson.com
Instagram: sci.cad
Twitter: calebadawson