Multilayered Gel-Spotting Device for In Vitro Reconstruction of Hair Follicle-like Microstructure

Area of Science:

• Regenerative Medicine
• Developmental Biology
• Biomaterials Engineering

Background:

• Hair follicles are crucial for hair development and skin appendage formation.
• Understanding early skin appendage development is key for regenerative strategies.
• Current in vitro models lack the complexity to fully mimic native hair follicle development.

Purpose of the Study:

• To develop a microgel-spotting device for fabricating a multilayered gel bead culture.
• To mimic early skin appendage development for in vitro hair follicle regeneration.
• To investigate the potential of a cytokine gradient in promoting cell interactions for follicle formation.

Main Methods:

• Fabrication of a three-layered gel bead: alginate core with cytokines, mouse embryonic stem cells in collagen middle layer, and epidermal cells in outer collagen layer.
• Utilizing a microgel-spotting device for precise control over cell number and gel bead size.
• Histological and immunohistological analyses to confirm reconstructed hair follicle structures.

Main Results:

• The microgel-spotting device enabled precise control over cell encapsulation and gel bead dimensions.
• A cytokine gradient within the alginate core promoted interactions between stem and epidermal cells.
• Reconstructed hair follicle structures, including keratinized centers, sweat gland-like tissue, and erector pili-like structures, were observed in vitro.
• Cell aggregates with structures resembling native hair follicles were formed.

Conclusions:

• The developed multilayered gel bead culture model shows significant potential for in vitro hair follicle regeneration.
• This model provides valuable insights into the early developmental processes of skin appendages.
• The microgel-spotting device offers a controllable platform for tissue engineering applications in dermatology.