Stem cells and calcium affect breast function

National Stem Cell Foundation of Australia

Brisbane scientist targets knowledge gap in women’s health

Mammary biologist Dr Felicity Davis is investigating how breasts change through life: how they develop during puberty, alter during pregnancy and change back after breastfeeding is complete.

A scientist at the University of Queensland’s Mater Research Institute, she is examining the role stem cells play in this remarkable tissue plasticity.

In recognition of her leadership in the field, she has received one of two annual $50,000 Metcalf Prizes from the National Stem Cell Foundation of Australia.

Felicity leads research that details how mammary glands form and how they function during lactation. Discovering how this happens at a molecular, cellular and tissue level will provide new insights when problems in the breast arise – ranging from breastfeeding difficulties to breast cancer.

Of particular interest is calcium signalling, a critical cellular communication process.

“Calcium signalling is a kind of messaging system that tells cells what to do while the mother is breastfeeding,” she explains.

“We look at calcium signals in cells of living mammary gland tissue from mouse models. When an individual cell fires, we can see this as an increase in fluorescence intensity under a microscope.

“We can then peer deep into the tissue and see how these signals are controlling that cell’s behaviour and how hundreds of these cells are interacting. There’s the twinkling effect of calcium signals firing, followed by cells contracting.”

Felicity’s initial research set out to pin down exactly how calcium itself is transported into milk during lactation, but she soon realised it was involved in many other processes.

After research stints in the US and UK, she set up her own lab at Mater Research Institute-University of Queensland, dedicated to exploring the biochemical and mechanical control of mammary gland formation and function.

“We don’t completely understand what makes these cells in developing mammary glands grow and divide, branch out and form these intricate complex structures in a very controlled manner, where every cell is exactly where it needs to be when it needs to be there,” she says.

“And then in pregnancy, we also don’t fully understand how stem and progenitor cells create many thousands of new cells that are capable of producing milk and making it available to the child precisely when they ask for it.

“We should be doing everything we can in order to understand how that happens physiologically, how the breast changes to allow that to happen and how it remodels after the process is complete.”

Photos and video

Dr Felicity Davis. Credit: Mater Research Institute, UQ
VIDEO: Calcium signals (green) tell mammary cells (red) to expel milk during lactation.
Credit: Mr Alexander Stevenson/Davis Lab, Mater Research Institute, UQ
Click on the image to view the video
Dr Felicity Davis. Credit: Mater Research Institute, UQ
Dr Felicity Davis. Credit: Mater Research Institute, UQ
Dr Felicity Davis. Credit: Mater Research Institute, UQ
Dr Felicity Davis. Credit: Mater Research Institute, UQ
Dr Felicity Davis. Credit: Mater Research Institute, UQ
The cells responsible for milk expulsion during lactation
Credit: Dr Felicity Davis, Mater Research Institute, UQ
Click on the image to download the high res TIFF
Breast epithelial cells in culture, viewed through a microscope
Credit: Dr Teneale Stewart/Davis Lab, Mater Research Institute, UQ