UC Merced

While bioprinting is well positioned for creating thick tissues and whole organs due to its scalability and geometric flexibility, it is limited in terms of microscale complexity. Reasons for this inadequacy includes limited resolutions, a lack of printable but biologically active materials, and a lack of use of stem cells. This issue permeates to vascularization, a universal requirement for artificial tissues, in which bioprinting has difficulty inducing microvasculature formation. In my dissertation, I address the lack of complexity in bioprinting by developing a multi-material bioprinter with novel features that improve resolution and embed hydrogels with concentration gradients of small molecules. I then print fragile induced pluripotent stem cells (iPSC), which are well-known for their propensity to self-assemble, and demonstrate their high viability in long term culture. I attempt to guide these iPSC towards vascular smooth muscle fate, but inadequate commercial antibodies forced me to pivot towards a study on characterization. Finally, I induce vascular network formation in printed endothelial cells and show the effects of printed VEGF concentration gradients on printed networks.