Title : Biofabrication of functional human intestinal tissue with villi and crypts using high-resolution 3D printing technique
The epithelium of the small intestine is composed of villi that protrude into the gut lumen like fingers and crypts that are epithelial invaginations. The architecture of villi and crypts is critical to maintain intestinal homeostasis and renewal. In recent years, researchers have explored several methods to engineer three dimensional (3D) intestinal tissue structures consisting of both villi and crypts. However, reproducing the complex architecture using a simple fabrication method while achieving both high resolution structures and good cell compatibility remains challenging. Here, we fabricated gelatin methacryloyl (GelMA) based intestinal crypt-villus scaffolds possessing physiologically relevant microstructures using our custom biological projection micro-stereolithography (BioPuSL) system. High-resolution intestinal scaffolds with 500 um tall villi and 250 um deep crypts were printed within 30 minutes. Human intestinal Caco-2 cells were seeded on the 3D printed intestinal tissue, and the cells exhibited strong adhesion and proliferation on the printed intestinal scaffold. After 21 days of cultivation, Caco-2 cells formed a complete monolayer from the bottom of the crypts to the top of the villi. Caco-2 cells on villi expressed characteristics of mature enterocytes showing apico-basal polarization as exhibited by actin filament and α-tubulin staining which indicates the presence of brush borders of polarized epithelium. This 3D intestinal tissue construct, with a complete epithelium, can serve as a physiologically relevant in vitro platform for studying human-microbiome interaction, disease diagnosis/prevention, and drug screening applications.
This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. The research was supported by LLNL LDRD-22-SI-002. Information release number LLNL-ABS-844898.
Audience Take Away:
- 3D printing technique using Bio projection micro-stereolithography (BioPuSL).
- Intestinal tissue engineering.
- Intestinal cell behavior on 3D tissue structure.