BME PhD Preliminary Exam announcement for Favour O. Afolabi (C. Lin, advisor)

Everyone is invited to attend the public presentation beginning at 1:30 pm.

Title: Dynamic gelatin hydrogels crosslinked by dithiolane-norbornene click chemistry to model pancreatic ductal morphogenesis

Date: July 17, 2025

Time: 1:30 p.m.

Location: SL220A in Indianapolis and Zoom -

Meeting ID: 974 8070 1184

https://purdue-edu.zoom.us/j/7039878692?omn=97480701184

Committee Members: Dr. Chien Chi Lin (Chair), Dr. Julie Liu, Dr. Sunghee Park, Dr. Tayler Hebner

Abstract:

Human induced pluripotent stem cells (hiPSCs) are increasingly utilized to study human development, including the organogenesis of derivatives from all three germ layers, and to model diseases. Stem cell fate, such as proliferation and differentiation, is regulated by a dynamic niche composed of extracellular matrix (ECM) components. However, the role of ECM-mediated cues, including matrix mechanics and biochemical composition, remains underexplored in iPSC and iPSC-derived cultures. These systems are often established using conventional 2D cultures or poorly defined 3D matrices like Matrigel, which lack physiological relevance. In this research proposal, dynamic gelatin-based dithiolane-norbornene hydrogels would be used as a platform for generating pancreatic ductal organoids. Specifically, we are leveraging existing biorthogonal chemistries (i.e., dithiolane ring opening and thiol-norbornene photopolymerizations) to fabricate hydrogels with tunable mechanical properties (i.e., on-demand matrix stiffening). Following mechanical characterization of these hydrogels, we explored the capacity of this platform to support viability and pluripotency on iPSCs upon on-demand stiffening. Next, we will adapt this hydrogel system to establish microporous annealed particle (MAP) scaffolds for the differentiation of pancreatic progenitors from hiPSCs. We expect that intrinsic microporosity of the MAP gels provides a unique “2D in 3D” architecture to support high efficiency of pancreatic progenitors comparable to 2D differentiation. Finally, iPSC-derived PP cells within MAP scaffolds will be terminally differentiated into pancreatic ductal cells with the expression of mutant-KRAS, a prevalent oncogene in pancreatic ductal cells, to evaluate their response to mechanical during morphogenesis.