Bioinspired Precision Engineering of Three-Dimensional Epithelial Stem Cell Microniches

Area of Science:

• Biomaterials Science
• Stem Cell Biology
• Regenerative Medicine

Background:

• Epithelial maintenance depends on stem cells in specialized niches called crypts.
• Engineered stem cell niches are crucial for regenerative medicine applications.
• Two-photon polymerization (2PP) enables precise fabrication of micro/nanostructures for niche engineering.

Purpose of the Study:

• To fabricate biomimetic constructs replicating limbal epithelial crypt geometry using 2PP.
• To investigate human limbal epithelial stem cell (hLESC) behavior within these engineered niches.
• To understand how niche spatial geometry influences stem cell fate and differentiation.

Main Methods:

• Fabrication of gelatin methacrylate-based microniches using 2PP.
• Seeding of hLESCs in xeno-free conditions within the fabricated microniches.
• Analysis of cell proliferation and differentiation marker expression along the microniche z-axis.

Main Results:

• Successful fabrication of biomimetic crypt-like structures.
• Observed hLESC proliferation and phenotypic zonation within the microniches without exogenous signals.
• Demonstrated significant differences in cell phenotype based on location within the microniche (base vs. rim).

Conclusions:

• Niche spatial geometry significantly influences hLESC fate and differentiation.
• 2PP offers a flexible method for creating biomimetic epithelial niches.
• These findings support the development of synthetic niche-based therapies for epithelial regeneration.