Combining electrospun nanofibers with cell-encapsulating hydrogel fibers for neural tissue engineering

Area of Science:

• Biomaterials Science
• Neuroscience
• Tissue Engineering

Background:

• Electrospun fibers are promising for neural tissue engineering, supporting stem cell differentiation and neurite growth.
• A critical need exists for methods to protect neural cells (neurons, glia) and stem cells seeded on electrospun fibers during transport and implantation.
• Interfacial polyelectrolyte complexation (IPC) offers a potential solution for creating cell-encapsulating hydrogel fibers.

Purpose of the Study:

• To develop and evaluate cell-encapsulating hydrogel fibers using IPC for neural tissue engineering applications.
• To assess the viability and neurite extension of primary neurons and astrocytes encapsulated within these hydrogel fibers.
• To compare the performance of hydrogel fibers made with different chitosan types (acid-soluble vs. water-soluble).

Main Methods:

• IPC-hydrogel fibers were fabricated by combining acid-soluble chitosan (AsC) or water-soluble chitosan (WsC) with cell-containing alginate.
• Primary spinal astrocytes, cortical neurons, and L929 fibroblasts were encapsulated within alginate before IPC fiber spinning.
• Cell viability was assessed at multiple time points (30 min, 4 h, 1 d, 7 d), and neuron neurite extension was evaluated using Tuj1 staining.

Main Results:

• Neurons encapsulated in WsC-based IPC-hydrogel fibers exhibited robust neurite extension, unlike those in AsC-based fibers.
• Good percentages of survival were achieved for primary neurons and astrocytes encapsulated in IPC-hydrogel fibers.
• Neurons de-encapsulated from AsC fibers extended neurites onto electrospun fibers, showing limited integration with the hydrogel fibers.

Conclusions:

• IPC hydrogel technology is effective for encapsulating neural cells, including primary neurons and astrocytes, with good survival rates.
• WsC-based IPC-hydrogel fibers support significant neurite extension, indicating their potential for neural regeneration.
• This study demonstrates the utility of IPC hydrogel fibers as a protective and supportive biomaterial for neural cells in tissue engineering scaffolds.