The journey of a sample

The INSIGHT study looks at how lactation starts within the first few days after childbirth. During this period the mother’s body shifts from sustaining a pregnancy to producing colostrum and then milk for her newborn infant. Lactation begins within 3-4 days after childbirth and is driven by hormones. The INSIGHT study aims to identify which hormones are involved and also understand how they act on the mammary gland.

INSIGHT depends on the generous mums who agree to donate samples of blood, colostrum and breastmilk in the first few days after giving birth. It also relies on a fantastic team of clinical research practitioners who travel to women’s homes to collect samples and give important breastfeeding advice at the same time.

So what happens to the samples that are taken?

A lot! These samples are very precious and therefore we make the most of every drop.  As soon as blood, colostrum and milk samples are collected they are kept cool in an ice bag and taken directly to the lab for processing and analysis.

We use the blood samples to measure a wide range of hormones. We then store what is left in the freezer, which gives us an accessible resource for future analysis.  

What are these samples going to tell us?

We use colostrum and breastmilk to generate new knowledge about the biology of human lactation. First, whole colostrum or breastmilk is separated by centrifugation into three layers: fat on top, plasma in the middle, and cells at the bottom.

These three components contain enormous amounts of information about what is happening in the mammary gland during lactation. The fat layer contains a molecule called RNA, which tells us about the genes that are involved in lactation. The plasma contains a range of molecules such as proteins, sugars and bioactive components. We analyse these components to characterise milk composition and to understand what molecules are produced by the mammary gland at the start of lactation. Finally, the bottom layer contains milk-producing mammary cells and immune cells.

We use techniques such as flow cytometry to understand how the cell composition changes from colostrum to breastmilk. We also use biochemical and molecular techniques to unravel the inner workings of these cells. Overall, breastmilk samples provide us with a window into the biology of human lactation that would otherwise remain hidden if it wasn’t for these donated samples.

Who will this research help?

The goal of the INSIGHT study is to help breastfeeding mothers who have difficulty producing milk. For example, once we learn about the normal hormone levels needed for initiating milk production after childbirth, we can then check for a hormonal problem in mothers with delayed onset of lactation or low milk supply.