Heterocellular spheroids of the neurovascular blood-brain barrier as a platform for personalized nanoneuromedicine

Abstract

Nanoneuromedicine investigates nanotechnology to target the brain and treat neurological diseases. In this work, we biofabricated heterocellular spheroids comprising human brain microvascular endothelial cells, brain vascular pericytes and astrocytes combined with primary cortical neurons and microglia isolated from neonate rats. The structure and function are characterized by confocal laser scanning and light sheet fluorescence microscopy, electron microscopy, western blotting, and RNA sequencing. The spheroid bulk is formed by neural cells and microglia and the surface by endothelial cells and they upregulate key structural and functional proteins of the blood-brain barrier. These cellular constructs are utilized to preliminary screen the permeability of polymeric, metallic, and ceramic nanoparticles (NPs). Findings reveal that penetration and distribution patterns depend on the NP type and that microglia would play a key role in this pathway, highlighting the promise of this platform to investigate the interaction of different nanomaterials with the central nervous system in nanomedicine, nanosafety and nanotoxicology.

Investigating receptor-mediated antibody transcytosis using blood–brain barrier organoid arrays

“…Previous work established that BBB organoids recapitulate key properties of the BBB observed in vivo [ 25 , 26 , 30 ] and constituted a major advance in the field. Specifically, organoid assembly increased expression of receptors involved in transcytosis, transporters, and tight junction proteins compared to a monoculture of endothelial cells [ 24 , 26 , 27 ]. Furthermore, it was shown that BBB organoids assembled with hCMEC/D3 cells reproduced the expected permeability of angiopep-2 whereas the same cells grown in a transwell model failed to do so [ 26 ].…”

“…Multiple groups have recently established a novel 3D model of the BBB formed by the self-organization of human brain endothelial cells, pericytes and astrocytes [ 24 – 27 ]. Self-assembled 3D BBB models allow direct cell–cell interactions in the absence of artificial membranes or substrates and, importantly, recapitulate key cellular and molecular properties of the BBB, including: (1) tight junction formation, (2) efflux pump expression and activity and (3) receptor-mediated transport of peptides [ 26 ].…”

Advances in Non-Animal Testing Approaches towards Accelerated Clinical Translation of Novel Nanotheranostic Therapeutics for Central Nervous System Disorders

“…Therefore, in this section, the nanomedicine studies for cell culture are confined to spheroids/assembloids, and organoids will be further discussed in the section on organ-on-chip microfluidics, in how they can be used in tandem with microfluidics for studying nanoparticle-BBB interactions as an alternative to in vitro cell cultures. As was shown by the findings of Sokolova and colleagues [140], Nzou and colleagues [140], and Kumarasamy and colleagues [141], the most robust models must as a prerequisite include the primary elements of the NVU (endothelial cells, astrocytes and pericytes), but further yet, the necessity of the addition of satellite cells such as the microglia to spheroid models, the so-termed "third element" of the NVU by Szepesi and colleagues [165], which accounts for 10-15% of total brain cells, is incontrovertible.…”

“…Perhaps the most exciting prospect of such 3D models is that they can spontaneously self-assemble to form scaffold free models of the BBB for permeability screening, i.e., spheroids, which accurately represent the brain physiologically and spatially [163,164]. More sophisticatedly, cells can form cerebral organoids in suitable scaffolding matrices, such as that developed by Nzou and colleagues [141]. For an excellent review of iPSC-derived BBB models including cerebral organoids for studying neurological disorders, consult the article recently published by Logan and colleagues [165] in comprehensive physiology.…”

Organoid Technology: A Reliable Developmental Biology Tool for Organ-Specific Nanotoxicity Evaluation

“…The blood–brain barrier (BBB) is impermeable to most of the conventional drugs whereas nano-drugs can penetrate through it, treating CNS and brain disorders ( Sokolova et al, 2020 ; Kumarasamy and Sosnik, 2021 ). However, NP-induced neurotoxicity needs to be evaluated properly using a suitable toxicity evaluation model.…”