Aligned Poly-l-lactic Acid Nanofibers Induce Self-Assembly of Primary Cortical Neurons into 3D Cell Clusters

Abstract

Relative to two-dimensional (2D) culture, three-dimensional (3D) culture of primary neurons has yielded increasingly physiological responses from cells. Electrospun nanofiber scaffolds are frequently used as a 3D biomaterial support for primary neurons in neural tissue engineering, while hydrophobic surfaces typically induce aggregation of cells. Poly-l-lactic acid (PLLA) was electrospun as aligned PLLA nanofiber scaffolds to generate a structure with both qualities. Primary cortical neurons from E18 Sprague–Dawley rats cultured on aligned PLLA nanofibers generated 3D clusters of cells that extended highly aligned, fasciculated neurite bundles within 10 days. These clusters were viable for 28 days and responsive to AMPA and GABA. Relative to the 2D culture, the 3D cultures exhibited a more developed profile; mass spectrometry demonstrated an upregulation of proteins involved in cortical lamination, polarization, and axon fasciculation and a downregulation of immature neuronal markers. The use of artificial neural network inference suggests that the increased formation of synapses may drive the increase in development that is observed for the 3D cell clusters. This research suggests that aligned PLLA nanofibers may be highly useful for generating advanced 3D cell cultures for high-throughput systems.

Biomimetic Electrospun PLLA/PPSB Nanofibrous Scaffold Combined with Human Neural Stem Cells for Spinal Cord Injury Repair

“…The PLLA nanofibrous scaffolds were relatively hydrophobic with a WCA of 128.30 ± 1.06°. This WCA agrees with previous studies as electrospun PLLA nanofibrous materials typically exhibit hydrophobic with WCA about 130° due to ester group and indicates insufficient hydrophilicity for promoting cell growth. − In contrast, the composite PLLA/PPSB nanofibrous scaffolds were relatively hydrophilic, and the WCA continuously decreased from 59.15 ± 13.10° to 47.13 ± 1.97° as the PPSB content in the composite scaffold increased from 20 to 60 wt %. With the addition of PPS polymers to the composition of PLLA nanofibers, the electrospun PPS/PLLA nanofibrous scaffolds showed relatively hydrophilic property which can be attributed to the presence of hydroxyl groups attached to the backbone of the PPS polymers. ,, Moreover, the presence of sulfonate groups onto the nanofibers would enhance the surface hydrophilicity of nanofibrous materials according to previous study due to the hydrophilic nature of sulfonate group. − Therefore, the hydrophilic property of the composite scaffolds was attributed to the hydroxyl groups attached to the PPSB polymer and the incorporation of sulfonate groups.…”

Tendon stem cells seeded on dynamic chondroitin sulfate and chitosan hydrogel scaffold with BMP2 enhance tendon-to-bone healing

“…Because growth factors cannot effectively act at the tendon-to-bone interface alone, they are often loaded on various biomaterials. At present, the research of biomaterials is mainly based on synthetic scaffolds such as poly-glycolic-acid and poly-L-lactic-acid [ 16 , 17 ], and natural scaffolds such as silk and collagen [ [ 18 , 19 ]], both of them having their own advantages and disadvantages. Compared with synthetic scaffolds, natural scaffolds contain a lot of biological information, and some specific amino acid sequences can interact with cells [ 20 , 21 ].…”

Tendon stem cells seeded on dynamic chondroitin sulfate and chitosan hydrogel scaffold with BMP2 enhance tendon-to-bone healing

“…4,15 Because growth factors cannot effectively act at the tendon-to-bone interface alone, they are often loaded on various biomaterials. At present, the research of biomaterials is mainly based on synthetic scaffolds such as poly-glycolic-acid and poly-L-lactic-acid, 16,17 and natural scaffolds such as silk and collagen, 18,19 both of them have their own advantages and disadvantages. Compared with synthetic scaffolds, natural scaffolds contain a lot of biological information, and some speci c amino acid sequences can interact with cells.…”