The project characterized basement membrane composition in the mouse small intestine using advanced microscopy, confirming the spatial distribution of laminin proteins, some with expression restricted to the intestinal crypt or the villus tip. However, the project showed that these changes in expression did not impact the stiffness of the tissue. To investigate whether these proteins have functional significance, in-vivo mouse models were used, in combination with engineered substrates with controlled and patterned protein composition and organoid culture systems that mimic intestinal tissue organization.
A key finding was that specific basement membrane proteins regulate the rate of epithelial cell extrusion—the process by which cells are shed from tissue, and can occur to both live or dead cells. This regulation occurs through activation of specific cellular signaling pathways, providing molecular insight into how extracellular matrix composition influences tissue homeostasis.
During the work on the project, the fellow acquired extensive skills including working with intestinal organoid cultures, microfabrication, protein patterning, atomic force microscopy, advanced live-imaging and confocal microscopy, as well as development of computational analysis pipelines. A detailed methodological protocol was published, providing tools now being adopted by other laboratories. The quantification frameworks developed are being applied to additional projects, demonstrating broader utility. These achievements position the researcher to establish an independent research team, further investigating extracellular matrix regulation of tissue behavior.