Initial astrocyte response to electrospun poly-l-lactic acid fibers of varying nanoscale diameters

We hypothesized that fiber diameter within an electrospun fiber scaffold would affect astrocyte elongation and maturation. To examine the relationship, astrocytes were seeded on 400nm and 800nm diameter electrospun PLLA fibers. Immunohistochemistry was used to monitor cell morphology, and GLT-1 expression over the first 96 hours after seeding. The results indicate that astrocytes extended along the primary axis of the 800nm fibers more rapidly than astrocytes seeded on fibers of half the size. While GLT-1 was expressed diffusely throughout the surface of the astrocytes, elongated cell processes exhibited dense regions of GLT-1. These results show that 800nm fibers allowed astrocytes to develop GLT-1 rich cellular processes more rapidly than 400nm fibers. These findings indicate that fiber diameter is an important parameter to consider when designing materials that regulate astrocyte physiology.