A Low Permeability Microfluidic Blood-Brain Barrier Platform with Direct Contact between Perfusable Vascular Network and Astrocytes

Abstract

A novel three dimensional blood brain barrier (BBB) platform was developed by independently supplying different types of media to separate cell types within a single device. One channel (vascular channel, VC) is connected to the inner lumen of the vascular network while the other supplies media to the neural cells (neural channel, NC). Compared to co-cultures supplied with only one type of medium (or 1:1 mixture), best barrier properties and viability were obtained with culturing HUVECs with endothelial growth medium (EGM) and neural cells with neurobasal medium supplemented with fetal bovine serum (NBMFBS) independently. The measured vascular network permeability were comparable to reported in vivo values (20 kDa FITC-dextran, 0.45 ± 0.11 × 10−6 cm/s; 70 kDa FITC-dextran, 0.36 ± 0.05 × 10−6 cm/s) and a higher degree of neurovascular interfacing (astrocytic contact with the vascular network, GFAP-CD31 stain overlap) and presence of synapses (stained with synaptophysin). The BBB platform can dependably imitate the perivascular network morphology and synaptic structures characteristic of the NVU. This microfluidic BBB model can find applications in screening pharmaceuticals that target the brain for in neurodegenerative diseases.

3D brain angiogenesis model to reconstitute functional human blood–brain barrier in vitro

“…With the exception of a recent model developed by Campisi et al (), none of the models have achieved vascular permeability comparable to that of the in vivo BBB. Although our model showed a higher permeability than that found in vivo, the vascular permeability of our 3D tri‐cultured vasculature was lower than those of the majority of previous 3D (Adriani et al, ; Bang et al, ; Herland et al, ; Wang et al, ) or 2D models (Booth & Kim, ; Nakagawa et al, ). Importantly, the significant difference in permeability between monoculture and tri‐culture conditions in our system indicates that endothelial–perivascular interactions may have contributed to the barrier phenotype of the BBB vasculature (Figure ).…”

“…Herland et al () used human primary brain ECs, astrocytes, and pericytes in a 3D model to reveal direct interactions among cells in the absence of any artificial barrier such as a porous membrane. In vitro models of the neurovascular unit consisting of 3D vasculature with neurons and astrocytes have also been introduced and contributed to the establishment of a coculture protocol for ECs and neuronal cells (Adriani, Ma, Pavesi, Kamm, & Goh, ; Bang et al, ; S. R. Lee et al, ). Campisi et al () developed a BBB model having a 3D self‐assembled vascular network by using iPSC‐ECs.…”

Modeling Nanocarrier Transport across a 3D In Vitro Human Blood‐Brain–Barrier Microvasculature

“…[ 33–36 ] Among the many 2D and 3D vascular models, only few 3D in vitro models of functional brain vasculature have been described. [ 37–39 ] However, they typically show larger diameters (600–800 µm) compared to brain vessels (arterioles and venules: 1–100 µm; capillaries: 5–10 µm), which results in altered transport properties. To address such limitations, a 3D in vitro microfluidic model of the human BBB microvasculature has been recently developed by the authors, by the triculture of human induced pluripotent stem cell‐derived ECs (iPSC‐ECs), primary human pericytes, and astrocytes in 3D fibrin hydrogel ( Figure ; Figures S1 and S2, Supporting Information).…”

Recreating Physiological Environments In Vitro: Design Rules for Microfluidic‐Based Vascularized Tissue Constructs

“…This results in the formation of a functional and perfusable vascular network. Through this method, Kim et al generated the vascular network to mimic vasculogenesis and angiogenesis processes, and with this platform, they further created the pericytes‐covered vasculature, vascularized bone and blood–brain barrier microenvironment by coculturing the relevant type of cells to better mimic the physiological state as well as the organ‐specific vasculature.…”