IADR Abstract Archives
Spheroids-on-Chip: Flow Enhances Osteodifferentiation of Periodontal Ligament-Derived Stem Cell Spheroids
Objectives: Periodontal ligament-derived mesenchymal stem cells (PDLSCs) are an attractive source for bone tissue engineering and regenerative strategies. However, the static culture conditions offered by traditional in vitro platforms for the culture of three-dimensional (3D) spheroids and constructs, limit the long-term survival and osteogenic potential of these PDLSCs. Microfluidic organ-on-chip platforms provide an opportunity to control and modulate the fluid flow, biomimic the blood flow and provide chemical/ biomechanical cues. Hence, the aim of the present study was to investigate the impact of dynamic culture conditions (using a spheroids-on-chip device) on the cellular viability, proliferation and osteogenic differentiation potential of PDLSC-spheroids.
Methods: PDLSC-spheroids (10,000 cells/spheroid; 1-day-old) were seeded onto a microfluidic spheroid perfusion chip. Fluid flow was controlled using a peristaltic pump. Computational fluid dynamics was used to determine the flow characteristics under low-flow (1.2µl/min) and high-flow (7.2µl/min) conditions. Static culture conditions were used as controls. Continuous flow of media was maintained for 7 days, and the spheroids were evaluated for their morphology, cellular viability (MTS assay), and osteogenic potential (alkaline phosphatase and osteocalcin activity).
Results: PDLSC-spheroids cultured under high-flow conditions were significantly larger at day-7 compared to static conditions (p<0.05). No significant difference in the morphology was observed between spheroids cultured in low-flow and static conditions. CFD modeling studies showed that the fluid shear stress generated within the chip was 0.037 dynes/cm2and 0.224 dynes/cm2 under low and high flow respectively. PDLSC-spheroids in high-flow conditions showed a marked increase in alkaline phosphate and osteocalcin level at day-7 compared with static conditions (p<0.05).
Conclusions: Fluid dynamics and shear stress provided by microfluidics enable the biomimicry of the physiological microenvironment. Hence, the microfluidic spheroids-on-chip biomimics the micro physiological conditions and provides a novel platform to fabricate PDLSC-spheroids with higher osteogenic and regenerative potential.
Methods: PDLSC-spheroids (10,000 cells/spheroid; 1-day-old) were seeded onto a microfluidic spheroid perfusion chip. Fluid flow was controlled using a peristaltic pump. Computational fluid dynamics was used to determine the flow characteristics under low-flow (1.2µl/min) and high-flow (7.2µl/min) conditions. Static culture conditions were used as controls. Continuous flow of media was maintained for 7 days, and the spheroids were evaluated for their morphology, cellular viability (MTS assay), and osteogenic potential (alkaline phosphatase and osteocalcin activity).
Results: PDLSC-spheroids cultured under high-flow conditions were significantly larger at day-7 compared to static conditions (p<0.05). No significant difference in the morphology was observed between spheroids cultured in low-flow and static conditions. CFD modeling studies showed that the fluid shear stress generated within the chip was 0.037 dynes/cm2and 0.224 dynes/cm2 under low and high flow respectively. PDLSC-spheroids in high-flow conditions showed a marked increase in alkaline phosphate and osteocalcin level at day-7 compared with static conditions (p<0.05).
Conclusions: Fluid dynamics and shear stress provided by microfluidics enable the biomimicry of the physiological microenvironment. Hence, the microfluidic spheroids-on-chip biomimics the micro physiological conditions and provides a novel platform to fabricate PDLSC-spheroids with higher osteogenic and regenerative potential.