Modelling a Human Blood-Brain Barrier Co-Culture Using an Ultrathin Silicon Nitride Membrane-Based Microfluidic Device

• Published in: International journal of molecular sciences Vol. 24; no. 6; p. 5624
• Main Authors: Hudecz, Diana, McCloskey, Molly C, Vergo, Sandra, Christensen, Søren, McGrath, James L, Nielsen, Morten S
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 15.03.2023; MDPI
• Subjects: Antibodies; Antibodies - metabolism; Astrocytes; Blood-brain barrier; Blood-Brain Barrier - metabolism; Brain - metabolism; CD147 antigen; Cell culture; Coculture Techniques; Collagen; Endothelial cells; Endothelial Cells - metabolism; Endothelium; Fibroblasts; High resolution; Humans; Kinases; Lab-On-A-Chip Devices; Medical imaging; Membranes; Microfluidic devices; Microfluidics; Microscopy; Microvasculature; Monoclonal antibodies; Morphology; Nervous system diseases; Neuroimaging; Permeability; Pharmaceutical industry; Physiological aspects; Scientific equipment and supplies industry; Silicon; Silicon compounds; Silicon nitride; Stem cells; tissue chips; Transferrin; Denmark; United States; Germany; blood-brain barrier; stem cells; tissue chips; microscopy; monoclonal antibodies
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms24065624

Understanding the vesicular trafficking of receptors and receptor ligands in the brain capillary endothelium is essential for the development of the next generations of biologics targeting neurodegenerative diseases. Such complex biological questions are often approached by in vitro models in combination with various techniques. Here, we present the development of a stem cell-based human in vitro blood-brain barrier model composed of induced brain microvascular endothelial cells (iBMECs) on the modular µSiM (a microdevice featuring a silicon nitride membrane) platform. The µSiM was equipped with a 100 nm thick nanoporous silicon nitride membrane with glass-like imaging quality that allowed the use of high-resolution in situ imaging to study the intracellular trafficking. As a proof-of-concept experiment, we investigated the trafficking of two monoclonal antibodies (mAb): an anti-human transferrin receptor mAb (15G11) and an anti-basigin mAb (#52) using the µSiM-iBMEC-human astrocyte model. Our results demonstrated effective endothelial uptake of the selected antibodies; however, no significant transcytosis was observed when the barrier was tight. In contrast, when the iBMECs did not form a confluent barrier on the µSiM, the antibodies accumulated inside both the iBMECs and astrocytes, demonstrating that the cells have an active endocytic and subcellular sorting machinery and that the µSiM itself does not hinder antibody transport. In conclusion, our µSiM-iBMEC-human astrocyte model provides a tight barrier with endothelial-like cells, which can be used for high-resolution in situ imaging and for studying receptor-mediated transport and transcytosis in a physiological barrier.