Polylysine-functionalised thermoresponsive chitosan hydrogel for neural tissue engineering

Area of Science:

• Biomaterials Science
• Neuroscience
• Tissue Engineering

Background:

• Neural tissue engineering requires biocompatible scaffolds that support neuronal survival and outgrowth.
• Chitosan-based hydrogels offer tunable properties for cell culture applications.
• Understanding cell-material interactions is crucial for designing effective neural scaffolds.

Purpose of the Study:

• To evaluate chitosan/glycerophosphate salt (GP) hydrogels as a 3D scaffolding for foetal mouse cortical cells.
• To investigate the effect of poly-D-lysine (PDL) immobilization on cell adhesion, survival, and neurite outgrowth in 2D and 3D cultures.
• To determine optimal conditions for neural cell culture within thermally responsive hydrogels.

Main Methods:

• Culturing foetal mouse cortical cells on 2D chitosan/GP films and within 3D hydrogels.
• Assessing cell number, cell morphology, and neurite outgrowth.
• Immobilizing poly-D-lysine (PDL) onto chitosan via azidoaniline photocoupling.
• Varying GP osmolarity and PDL concentrations.

Main Results:

• Isotonic GP concentrations promoted optimal cell survival.
• Immobilized PDL improved cell survival in 3D hydrogels up to 0.1%, but higher concentrations inhibited outgrowth.
• Neurons in 3D hydrogels exhibited larger cell bodies and single neurites, differing from 2D cultures.
• PDL concentration had more pronounced effects on cell behavior in 3D compared to 2D cultures.

Conclusions:

• Thermally responsive chitosan/GP hydrogels provide a suitable 3D environment for neural tissue engineering.
• Optimized PDL immobilization can enhance neural cell survival and outgrowth in 3D scaffolds.
• Hydrogel osmolarity and cell-material interactions are critical factors for neural cell behavior in engineered tissues.