Li Yao, Karen Bustamante-Fuchs, Kayla Cantu, Teresa Shippy
Collagen is a major extracellular matrix component, and soy protein has been reported to influence cellular and immune-related processes. Nanofiber scaffolds incorporating collagen and soy protein isolate (SPI) may provide a platform for modulating cell-material interactions in neural systems. In this study, we fabricated electrospun nanofibers composed of collagen (CO), SPI, and polycaprolactone (PCL) and investigated the cellular and transcriptional responses of human astrocytes to these scaffolds in vitro. The nanofibers were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and contact angle analysis. Human fetal astrocytes exhibited high viability on all nanofiber scaffolds. Flow cytometry analysis indicated that incorporation of SPI into CO/PCL nanofibers did not alter cell cycle distribution. Aligned nanofibers provided directional guidance for astrocyte migration. RNA-sequencing analysis revealed enrichment of the "neurodegeneration" and "antigen processing and presentation" pathways among the down-regulated genes in cells on CO/SPI/PCL fibers compared with CO/PCL fibers. Down-regulated genes in these pathways include IL1B, IL6, HLA-B, HLA-DMB, HLA-DPA1, and HLA-DRA. The "focal adhesion" pathway is enriched among up-regulated genes, which include COL4A1, COL4A2, FN1, LAMB1, LAMB2, AKT2, RAC1, RAC2, ROCK2, and PIP5K1A. These results demonstrate that incorporation of SPI into collagen-based nanofibers modulates astrocyte migration and gene expression profiles associated with focal adhesion and immune-related pathways, providing a foundation for further investigation of SPI-containing biomaterials in neural tissue engineering applications.