Photo-click Decellularized Matrix Hydrogels for Generating Pancreatic Ductal Organoids

Area of Science:

• Biomaterials Science
• Stem Cell Biology
• Organoid Technology

Background:

• Human induced pluripotent stem cells (iPSCs) are used to generate pancreatic ductal organoids (PDOs) for disease modeling and drug screening.
• Current PDO generation relies on Matrigel, a tumor-derived matrix with undefined composition and properties that can promote oncogene expression.
• Matrigel's limitations hinder mechanistic studies of cell-material interactions due to its weak mechanical properties.

Purpose of the Study:

• To investigate photo-clickable decellularized small intestine submucosa-norbornene (dSIS-NB) hydrogels as a Matrigel replacement for human iPSC-derived PDO generation.
• To evaluate the impact of hydrogel stiffness on PDO differentiation and functionality.
• To assess the potential of dSIS-NB hydrogels for creating robust models of pancreatic ductal tissue.

Main Methods:

• Pancreatic progenitors (PP) were differentiated from iPSCs in 2D culture, aggregated into spheroids, and then encapsulated in dSIS-NB hydrogels with tunable stiffness.
• Organoid differentiation and functionality were assessed via morphology, key ductal marker expression, and forskolin-induced swelling.
• Single-cell RNA sequencing (scRNA-seq) was employed to analyze the cellular composition and differentiation trajectory within the organoids.

Main Results:

• PDOs generated in stiffer dSIS-NB hydrogels (∼2.5 kPa) maintained a ductal epithelial phenotype and showed functional forskolin-induced swelling.
• Softer dSIS-NB hydrogels (∼0.9 kPa) and Matrigel led to a mesenchymal phenotype and failed to produce functional PDOs.
• scRNA-seq confirmed that stiffer dSIS-NB hydrogels significantly promoted ductal cell differentiation, achieving over 97% ductal progeny.

Conclusions:

• Photo-clickable dSIS-NB hydrogels represent a promising, tunable, and defined alternative to Matrigel for generating functional human iPSC-derived PDOs.
• Hydrogel stiffness is a critical factor in directing pancreatic progenitor differentiation towards a ductal fate.
• Stiffer dSIS-NB hydrogels facilitate the creation of more accurate and robust PDO models for pancreatic research.