Seminar - Stem cell activity in the mammary epithelial cells
Johanna Englund from the Institute of Biotechnology, University of Helsinki, Finland will present a talk with the title "Stem cell activity in the mammary epithelial cells is regulated by Laminin attachment".
Adult stem cells maintain tissue homeostasis and integrate various signals from the surrounding stem cell niche. The niche consists of supporting cells and an extracellular matrix (ECM) component, which together regulate stem cell activity to maintain sufficient amounts of stem and differentiated cells in the tissue.
While advances have been made in the characterization of core properties of niche-stem cell interactions, the precise role of ECM or its alterations in regulation stem cell activity is unclear. Decrease in stem cell activity can manifest as insufficient regeneration, but excessive numbers and activity of stem cells can render the tissue more prone to cancer. Mammary epithelium undergoes extensive proliferation and remodeling throughout the reproductive lifespan.
Thus, it is an excellent tissue system to study the dynamic interactions between extracellular microenvironment and epithelial stem cells. Our results demonstrate that while the ultrastructure of mammary epithelium or ECM does not change markedly during aging, the expression of basement membrane (BM) Laminins, specifically Laminin a5, in the mammary epithelium is different in young and old individuals.