Imprinted Binary Colloidal Crystals Support Growth and Stemness of Mouse Embryonic Stem Cells

Area of Science:

• Biomaterials Science
• Stem Cell Biology
• Surface Engineering

Background:

• Maintaining stemness of mouse embryonic stem cells (mESCs) in vitro is crucial for applications.
• Biophysical factors, particularly surface topography, influence stem cell behavior.
• Multidirectional symmetries in surface patterns show potential for limiting cell-substrate interactions and improving stemness.

Purpose of the Study:

• To develop and evaluate novel micro/nanotopography substrates for enhanced mESC culture.
• To investigate the role of combined micro- and nanotopography in regulating mESC attachment, spreading, and stemness.
• To explore the potential of these substrates for efficient stem cell expansion.

Main Methods:

• Fabrication of imprinted substrates using parylene-C coated binary colloidal crystals (BCCs) to create concave bowl-like micro/nanotopographies.
• Characterization of imprinted structures, including sub-2 μm feature fidelity.
• Culturing mESCs on substrates with varying micro- and nanotopographies (5 μm and 110 nm imprints).
• Assessment of mESC response, including attachment, spreading, colony morphology, growth rate, and expression of stemness markers in the presence of LIF.

Main Results:

• Parylene-C coating successfully imprinted sub-2 μm structures, creating defined micro/nanotopographies.
• Nanoroughness influenced cell attachment, while microroughness limited cell spreading.
• Substrates combining 5 μm and 110 nm imprints resulted in spatially limited cell attachment.
• Improved mESC colony shape, enhanced growth rate, and upregulated stemness marker expression were observed.

Conclusions:

• The combination of micro- and nanotopography on imprinted BCCs effectively regulates mESC-substrate interactions.
• These novel substrates promote improved stemness maintenance and expansion of mESCs in vitro.
• The findings contribute to the development of advanced cell culture platforms for tissue engineering and regenerative medicine.