Nanofiber-Mache Hollow Ball Mimicking the Three-Dimensional Structure of a Cyst

The occasional malignant transformation of intracranial epidermoid cysts into squamous cell carcinomas remains poorly understood; the development of an in vitro cyst model is urgently needed. For this purpose, we designed a hollow nanofiber sphere, the nanofiber-mache ball. This hollow structure was fabricated by electrospinning nanofiber onto alginate hydrogel beads followed by dissolving the beads. A ball with approximately 230 mm(3) inner volume provided a fibrous geometry mimicking the topography of the extracellular matrix. Two ducts located on opposite sides provided a route to exchange nutrients and waste. This resulted in a concentration gradient that induced oriented migration, in which seeded cells adhered randomly to the inner surface, formed a highly oriented structure, and then secreted a dense web of collagen fibrils. Circumferentially aligned fibers on the internal interface between the duct and hollow ball inhibited cells from migrating out of the interior, similar to a fish bottle trap. This structure helped to form an adepithelial layer on the inner surface. The novel nanofiber-mache technique, using a millimeter-sized hollow fibrous scaffold, is excellently suited to investigating cyst physiology.

Automated summary

A novel hollow nanofiber sphere model was designed for investigating the development of intracranial epidermoid cysts, allowing observation of oriented cell migration and collagen fibril secretion in the structure.