MIMICKING BLOOD FLOW USING A NEAR IN VIVO MICROFLUIDIC SYSTEM TO STUDY CHEMICALS AND NANOMATERIALS (CNMS) METABOLIC RESPONSE

BACKGROUND-AIM To develop new methods which will enhance improvement of safety and sustainability assessments of chemicals and nanomaterials (CNMs), an EU funded research and innovation project “IMPLEMENTING INNOVATIVE METHODS FOR SAFETY AND SUSTAINABILITY ASSESSMENTS OF CHEMICALS AND MATERIALS PARTICULARLY AT NANO LEVEL IN THE EUROPEAN UNION (CheMatSustain)” is including 10 EU partners (and UK Associated partner). Related to safety assessments, an in vitro static condition has been adapted to dynamicity to mimic blood flow in a new microfluidic near in vivo model. The experimental approach started with physicochemical CNMs characterization (DLS, Z-Potential, AFM, HR-SEM/TEM - UV-VIS, FT-IR, SIMS, DSC, TGA, UPS/XPS and AI-Artificial Intelligence). EA.hy926 vascular endothelial cell has been used to set up the static experimental condition and has been translated to the dynamic microfluidic one. The microfluidic system consists of a pump that generates a physiological blood flow in chambers containing the endothelial cells in different CNMs treatments considtions. METHODS CNMs characterization has been supported by AI to profile the similarities and differences of the UPS/XPS photoelectron spectra analysed. The assessment of CNMs effects was performed considering cell viability, cell morphology, cell toxicity (ROS production) and inflammatory response (TLR signalling pathway activation: IRAK-1, IL-6 and miR-146a expressions). RESULTS Depending on physicochemical CNMs characteristics, our results demonstrate that viability, cell morphology and toxicity are differently affected in static related to dynamic conditions. This latter seems to protect CNMs from toxicity. CNMs can affect cell morphology in both models. Ongoing transcriptomics and inflammatory response analyses are evidencing mechanistic processes. CONCLUSIONS Considering that shear stress created by flow can maintain the quiescence and integrity of endothelial cells, the microfluidic near in vivo condition demonstrated that blood flow may protect from the CNMs cytotoxicity observed during static conditions. This innovative approach can mimic a cause-and-effect relationship between various types of blood circulating CNMs. Fluidic system for advanced cell culture allows better mimicking the in vivo environment and physiologically-like conditions.