Examining the Interplay between Collagen Alignment and Bioceramic Incorporation on Osteoblast Cell Proliferation, Differentiation and Mineralization.

Biomimetic scaffolds provide essential biophysical and biochemical cues to guide cell behavior. Although the effects of biomaterial-directed cues on cell response have been widely reported. few studies have sought to decouple these effects to better understand the interplay between the different physicochemical factors on tissue-specific cell function. In this study, beta-tricalcium phosphate (B-TCP) was incorporated into electrochemically aligned collagen (ELAC) and random collagen threads, and the individual and interactive effects of biophysical and biochemical cues on osteoblast proliferation, differentiation, and mineralization were investigated. ELAC threads were prepared from collagen solution with 13-TCP using isoelectric focusing. Pure ELAC threads were prepared without 0-TCP. Random collagen threads with and without 0-TCP were prepared by casting neutralized collagen solution into a PLA mold and incubating at 37 °C for 60 inin to induce fibrillogenesis. Confirmation of B-TCP incorporation and validation of collagen fiber alignment was carried out using scanning electron microscopy (SEM) and polarized light microscopy (PLM). Tensile tests were perforined to assess the mechanical properties of collagen threads. Saos-2 cells were seeded on threads to assess cell proliferation, differentiation. and mineralization. Results from SEM and PLM confirmed that collagen fiber alignment in ELAC was retained upon 13-TCP incorporation. ELAC threads were significantly stronger and stiffer (p < 0,05) than random collagen threads, Alkaline phosphatase (ALP) activity was significantly higher (p < 0,05) in ELAC threads compared to random threads. In addition, M-TCP incorporation into ELAC significantly augmented (p < 0.05) cell metabolic activity, ALP activity, and cell-mediated calcium deposition, In conclusion, results from this study indicate that topographical cues from aligned collagen significantly enhance osteoblast function which was further augmented by D-TCP incorporation. Overall, 13-TCP incorporation into aligned collagen framework can yield biomimetic functional scaffolds for bone regeneration applications. [ABSTRACT FROM AUTHOR]