Engineered Three-Dimensional Microenvironments with Starch Nanocrystals as Cell-Instructive Materials.

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Cellular Microenvironments

Background:

• Cells naturally exist in 3D microenvironments with topographical, mechanical, and biochemical cues.
• Current studies often use 2D substrates, not fully replicating native conditions.
• Developing 3D systems is crucial for understanding cell behavior in physiologically relevant contexts.

Purpose of the Study:

• To create 3D nanocomposite hydrogels mimicking native cellular microenvironments.
• To investigate the impact of starch nanocrystals (SNCs) on hydrogel properties and cell behavior.
• To assess the potential of these hydrogels for cartilage tissue engineering.

Main Methods:

• Fabrication of 3D nanocomposite hydrogels with varying concentrations of starch nanocrystals (SNCs) in a gelatin matrix.
• Characterization of hydrogel mechanical properties (compressive modulus) and swelling ratio.
• Assessment of encapsulated L929 fibroblasts and ATDC5 chondrogenic progenitor cells for viability, metabolic activity, proliferation, and morphology.

Main Results:

• Incorporation of SNCs increased hydrogel compressive modulus, offering tunable mechanical properties without altering swelling.
• All hydrogel formulations demonstrated excellent cytocompatibility (>90% viability) for both cell types.
• Encapsulated fibroblasts exhibited elongated morphology, while ATDC5 cells showed a rounded morphology, particularly in SNC-containing hydrogels, suggesting differential cell response.

Conclusions:

• The developed gelatin/SNC nanocomposite hydrogels provide a tunable 3D microenvironment that supports cell viability and proliferation.
• The distinct cellular morphologies observed indicate potential applications in cartilage tissue engineering.
• Topographical and mechanical cues in 3D systems are powerful tools for instructing cell behavior.