Algae-based flexible localized oxygen control around Cells: An approach leading to more Biomimetic microphysiological systems
Abstract
Oxygen levels are crucial in the cellular microenvironment, affecting cellular function. Controlling pericellular oxygen is essential for understanding cell-oxygen interactions, disease mechanisms, and developing therapies. In this study, an algae strain was engineered as a biological oxygen-control material, integrated with a light-controlled microphysiological system to regulate pericellular oxygen. This technique could provide different oxygen levels and varying profiles for different locations within one microphysiological system. Additionally, the pericellular oxygen dynamics were faster than those achieved by other methods. By utilizing this algae-integrated microfluidic chip, mesenchymal stem cells differentiated into adipocytes with improved phenotypic characteristics, including increased numbers and sizes of lipid droplets, under 21-day stage-specific oxygen concentrations. Furthermore, this technique effectively mitigated the need to vent significant amounts of oxygen or nitrogen into the laboratory during long-term or virus-infested experiments, thereby enhancing both safety and practicality. The algae-integrated microfluidic chip also served as a platform for constructing a stroke-related vascular-on-chip model, enabling the evaluation of the protective effects of oxygen therapy on endothelial injury induced by oxygen-glucose deprivation/reperfusion (OGD/R). The results indicated that waving hyperoxic dynamics were most effective in safeguarding vascular tissue against OGD/R compared to other hyperoxic dynamics. This finding can guide the clinical oxygen inhalation mode during stroke management. All the aforementioned results demonstrated that the algae-light microphysiological system offered a technical platform capable of precise, dynamic pericellular oxygen control across the disciplines of biology and pharmaceutics. Moreover, The cost-effective cultivation of algae on a large scale made this method suitable for wider use.