Abstract Human cerebral organoids derived from induced pluripotent stem cells (iPSCs) provide novel tools for recapitulating the cytoarchitecture of human brain and for studying biological mechanisms of neurological disorders. However, the heterotypic interactions of neurovascular units, composed of neurons, pericytes, astrocytes, and brain microvascular endothelial cells, in brain-like tissues are less investigated. The objective of this study is to investigate the impacts of neural spheroids and vascular spheroids interactions on the regional brain-like tissue patterning in cortical spheroids derived from human iPSCs. Hybrid neurovascular spheroids were constructed by fusion of human iPSC-derived cortical neural progenitor cell (iNPC) spheroids, endothelial cell (iEC) spheroids, and the supporting human mesenchymal stem cells (MSCs). Single hybrid spheroids were constructed at different iNPC: iEC: MSC ratios of 4:2:0, 3:2:1 2:2:2, and 1:2:3 in low-attachment 96-well plates. The incorporation of MSCs upregulated the secretion levels of cytokines VEGF-A, PGE2, and TGF-β1 in hybrid spheroid system. In addition, tri-cultured spheroids had high levels of TBR1 (deep cortical layer VI) and Nkx2.1 (ventral cells), and matrix remodeling genes, MMP2 and MMP3, as well as Notch-1, indicating the crucial role of matrix remodeling and cell-cell communications on cortical spheroid and organoid patterning. Moreover, tri-culture system elevated blood-brain barrier gene expression (e.g., GLUT-1), CD31, and tight junction protein ZO1 expression. Treatment with AMD3100, a CXCR4 antagonist, showed the immobilization of MSCs during spheroid fusion, indicating a CXCR4-dependent manner of hMSC migration and homing. This forebrain-like model has potential applications in understanding heterotypic cell-cell interactions and novel drug screening in diseased human brain.
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TERMIS AM
Human induced pluripotent stem cell (hiPSC)-derived brain spheroids can recapitulate the complex cytoarchitecture of the brain as well as the genetic/epigenetic footprint of human brain development. Although the brain spheroids can mimic the structures and functions of the brain in vivo at certain complexity, the 3D models do not have a perfusable microvascular network that can provide the interaction with spheroids. Here we report on a microfluidic-based three-dimensional, cortical spheroid tissue grafted on the vascular-network. Angiogenic sprouting was induced by using concentration gradient-driven angiogenic factors and its vascularized network was characterized in terms of morphology, directional alignment under perfusion, lumen formation, and permeability. This paper demonstrates the potential utility of a membrane-free in vitro cortical spheroid tissue construct with perfusable microvascular network that can be scaled up to a high throughput platform as a cost-effective alternative platform to model brain diseases and disorders.
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- Award ID(s):
- 2100987
- PAR ID:
- 10430431
- Date Published:
- Journal Name:
- Development of Cortical Spheroid Tissue Constructs with Perfusable Microvasculature Platform
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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