Real-time Multiscale Imaging of Pathological Calcification - Zooming in on Aortic Valve Calcification

Calcifying Aortic Valve Disease (CAVD) is a cellular-driven disease that actively alters the structure and composition of the valve extracellular matrix, leading to severe disfunction of the heart.

Because the molecular mechanisms underlying CAVD are still unknown, there are currently no drug-based therapies and valve replacement is the only available treatment.Specifically, it is still unknown (1) how the disease modifies the extracellular matrix (ECM) to become susceptible for mineralization, (2) how cell differentiation and matrix modification lead to calcification, and (3) how the mineral develops within the matrix.

We lack these answers mainly due to our inability to characterize matrix development with the required chemical and structural details during the CAVD process.

I aim to push our capability for in situ imaging of ongoing biological matrix formation processes from the micron to the nanometer scale by creating a designer tissue imaging platform for CAVD.

This will be achieved by: •creating a human CAVD-on-a-chip that allows the application of mechanical and (bio)chemical cues to accurately emulate the early stages of CAVD;•designing the chip to accommodate a 3D correlative multiscale imaging and spectroscopy workflow to study matrix modification and mineralization in the native state from the micrometer to the nanometer scale; •developing a method to (1) collect cryo-sections from the ECM created at precisely selected points in space and time, to (2) transfer these to a transmission electron microscope and (3) revive -inside the microscope- the biological processes that are ongoing in the at the moment of cryo-arrest.

This will allow for the first-ever dynamic nanoscale imaging of ongoing ECM processes.These new capabilities will allow breakthroughs in understanding the role of matrix interactions in aortic calcification, opening the way for future development of drug-based treatments for CAVD.