Design and Validation of a Volumetric-extrusion Bioprinter for Bioprinting of Soluble Basement Membrane Extract for...

In translational research, 3D in vitro models are essential for advancing scientific understanding and therapeutic development. To this aim, Soluble Basement Membrane Extracts (SBMes), derived from mouse sarcoma cells, play the key role of replicating mechanical and biochemical features of in vivo microenvironment. They are particularly valuable in a variety of research fields, from tissue engineering to drug testing. In particular, they have become fundamental in cancer research as traditional 2D cell cultures, widely used in the field, can provide misleading information since they do not capture the three-dimensional (3D) structure and tumor microenvironment. In cancer research, effective 3D in vitro models are crucial for better understanding cancer evolution and anticipating challenges, such as drug resistance mechanisms. Organoids have emerged as promising 3D in vitro models, offering a more accurate representation of tumor biology. They grow in SBMes as they create an environment where cells can grow and self-organize into 3D structures. However, SBMe presents significant challenges, including low mechanical properties and complex rheological behavior, preventing its use with commercially available pneumatic-extrusion bioprinting systems. To address these limitations, we developed a low-cost, volumetric-controlled bioprinting system and a specific protocol for printing structures with SBMe. This system is based on a volumetric extruder and overcomes the limitations of traditional pneumatic-driven approaches. Once assembled and programmed with a specific g-code, the system can bioprint both pure and diluted SBMe to obtain both single and multi-layer constructs. This approach offers a more reliable and scalable method for producing 3D cell culture models, paving the way for more effective research into novel treatments and drug testing.