Quantification of 3D network geometry in collagen hydrogels.

Cancer is one of the principal causes of death in the world. Despite of the fact that there are ways of fighting the disease, full understanding about cancer cells behaviour is still distant. Extracellular matrix (ECM) is the three-dimensional environment where cells live, and its arrangement is known to modulate cell fate. Study of how ECMcancer cell interactions affect tumour progression is key for developing more effective drugs to heal cancer. As collagen is the most abundant ECM component, collagen hydrogels can be used as ECM models for research. This bachelor thesis is focused on proposing a processing pipeline for the extraction and characterization of fibre network from collagen hydrogel’s reflection microscopy images. This pipeline is composed by an image binarization procedure and a fibre network extraction algorithm from which the network parameters (i.e., fibre length, fibre persistence length, and crosslink density) are computed. The whole pipeline was tested in order to ensure its consistency, and eventually used for the characterization of real collagen hydrogel reflection microscopy images at different gel concentrations introduced in two types of in vitro platforms, culture wells and microfluidic devices. The study showed that fibre length and persistence length are similar for the different concentrations, while the network pore size decreases as the collagen concentration of the hydrogel increases. The future final step of the project would be to introduce cancer cells along with collagen hydrogels in the two platforms, and observe how collagen (ECM) disposition and characteristics direct cancer cell behaviour.