Human iPSC-Derived Endothelial Cells and Microengineered Organ-Chip Enhance Neuronal Development

Abstract

SummaryHuman stem cell-derived models of development and neurodegenerative diseases are challenged by cellular immaturity in vitro. Microengineered organ-on-chip (or Organ-Chip) systems are designed to emulate microvolume cytoarchitecture and enable co-culture of distinct cell types. Brain microvascular endothelial cells (BMECs) share common signaling pathways with neurons early in development, but their contribution to human neuronal maturation is largely unknown. To study this interaction and influence of microculture, we derived both spinal motor neurons and BMECs from human induced pluripotent stem cells and observed increased calcium transient function and Chip-specific gene expression in Organ-Chips compared with 96-well plates. Seeding BMECs in the Organ-Chip led to vascular-neural interaction and specific gene activation that further enhanced neuronal function and in vivo-like signatures. The results show that the vascular system has specific maturation effects on spinal cord neural tissue, and the use of Organ-Chips can move stem cell models closer to an in vivo condition.

Human induced pluripotent stem cell-derived neuroectodermal epithelial cells mistaken for blood-brain barrier-forming endothelial cells

“…Several groups have developed strategies that simultaneously differentiate human pluripotent stem cells (hPSC) to both neural and EC lineages, rationalizing that this co-differentiation yields hPSC-derived ECs possessing BBB attributes (Fig. 1a, referred to as neuroendothelial iBMECs) 10–22 . To assess the properties of these cells, we compared this protocol to a well-established method in which ECs are differentiated from pluripotent sources through a mesodermal lineage (referred to as mesoendothelial iECs; Fig 1a) 31 , using two IPS cell lines (IMR90-4 and H6) and one ES cell line (H1).…”

“…Recently, the generation of a pure population of putative BMECs from pluripotent stem cell sources (iBMECs) has been described to meet the need for a reliable and reproducible in vitro human BBB model 10–22 . Human pluripotent stem cells, embryonic or induced, can differentiate into large quantities of specialized cells in order to study development and model disease 23–27 .…”

Developmentally inspired human ‘organs on chips’

“…Induced pluripotent stem cell (iPSC) approaches have also been leveraged to create various types of specialized cells for organ chip studies, including cardiomyocytes, kidney podocytes, brain microvascular endothelial cells, and intestinal enterocytes (Wang et al, 2014(Wang et al, , 2017Musah et al, 2017;Workman et al, 2018), but their clinical relevance is sometimes questioned because most iPSCs generated in vitro remain fetal-like or neonatal in nature. Importantly, culturing iPSC-derived motoneurons and brain microvascular endothelial cells together in an organ chip model of the neuromuscular unit significantly enhanced function and in vivo-like maturation of spinal cord neural tissue (Sances et al, 2018). When cultured on chip, human iPSC-derived kidney podocytes also matured further by extending long foot processes much as they do in vivo (Musah et al, 2017).…”

“…1A,B; Huh et al, 2010). Since this study was published, multi-channel design approaches have been used by multiple research groups to build microfluidic organ-chip models of the human lung small airway, skin, kidney, intestine, placenta, blood-retinal barrier, blood-brain barrier, neurovascular unit and neuromuscular unit, among others (Kim et al, 2012;Achyuta et al, 2013;Abaci et al, 2015;Benam et al, 2016a;Lee et al, 2016;Musah et al, 2017;Yeste et al, 2017;Wang et al, 2017;Workman et al, 2018;Kasendra et al, 2018;Sances et al, 2018; reviewed by Bhatia and Ingber, 2014).…”

A robotic platform for fluidically-linked human body-on-chips experimentation

“…An automated experimental system that can meet these goals needs to be highly multifunctional and must ideally enable fluid handling and sample collection, perfusion of fluid through multiple linked microfluidic Organ Chip devices, and tissue imaging, all within a controlled temperature, humidity, and CO2 environment. Custom assemblies using syringe pumps 12 , peristaltic pumps 13 , micropumps 11,14,15 , and gravity feed 10,16,17 , including several commercial platforms 18,19 , can be used to perfuse and link microfluidic tissue and organ culture inside incubators; however, these systems do not facilitate the features necessary for complex HuBoC experimentation. In particular, these systems offer limited ability to sample the different biological compartments or the capacity to reconfigure the system so that the same platform can be used for multiple experimental designs.…”