Researchers at the University of Minnesota are using 3D bioprinting to create more accurate models for studying cancer cells and treatments. The traditional method of looking at cells is to sandwich a tissue sample between two glass slides and view them under a microscope; the glass slides put everything on the same plane so that a single focal length of the microscope can clearly view a wide frame of cellular activity. Alternatively, a microscope can be positioned directly over a flat Petri dish to observe a sample on its surface. Both of these methods have the same drawback: they create a 2D environment that doesn’t accurately replicate the natural 3D environment that exists in our bodies. As such, cells behave differently in Petri dishes than they do in the 3D environments that are our bodies.
But 3D bioprinting can replicate 3D environments as well as precisely position cells and drugs in those environments, providing a more accurate analogue to the human body that allows cells to behave as they normally would. “Testing anti-cancer drugs and cell therapies are both concepts that the University of Minnesota is world renowned for, and, with this model, we continue to be on the forefront of those innovations,” said Daniel Vallera, Professor of Therapeutic Radiology-Radiation Oncology at the University of Minnesota Medical School. “Something like this can yield some very important answers between the relationship of vasculature and drugs because this is modular; you can add elements to it and make it more sophisticated. You can even use the patients’ own tumor cells in this model.”
The efficacy of drugs is dependent upon the lab-observed cellular activity matching the activity of cells in our bodies, and accurate models are essential to achieving that match. Angela Panoskaltsis-Mortari is the Vice Chair for Research and Professor in the Department of Pediatrics at the University of Minnesota Medical School as well as Director of the 3D Bioprinting Facility; she elaborates, “This model is more consistent with what the body is like, and, therefore, studying the effects of drugs with human cells at this level makes the results more meaningful and predictive of what will happen in the body.”
Only 3D printing can handle the materials and geometries necessary to fabricate these environments as explained by Michael McAlpine, Associate Professor of Mechanical Engineering in the College of Science and Engineering and co-corresponding author on the paper, “All of this is enabled by our custom-built 3-D printing technology, which allows us to precisely place clusters of cells and chemical depots in a 3-D environment.”
Fanben Meng, Post-Doctoral Associate in the College of Science and Engineering provides more detail on the gradients created by the 3D bioprinter, stating, “One of the reasons this model is successful is that we are better able to control the environment. We are able to slowly cause the release of the chemical mediators and create a chemical gradient. It gives the cells time to behave in a way that’s similar to what we think happens in the body.” Tumors spread in a gradiated manner so it’s critically important to allow them to behave similarly in the lab.
Recently, researchers 3D printed a model of a protein to better visualize the way it bonds to other proteins. So often, 3D printing is used to create a 3D version of something that had previously been limited to two dimensions.