3D tissue engineered ischemic stroke model
Final Report Abstract
Ischemic stroke caused by blood vessel occlusion results in reduced brain function due to the neuronal necrosis. Approaches aimed at the restoration of homeostasis and neuronal regeneration remain unsuccessful due to the lack of appropriate research models for adequate drug validation prior to clinical studies. The aim of this project was to develop a novel 3D tissue engineered human neurovascular unit which would recapitulate the pathophysiology of stroke in vitro. We developed a bioengineered model of three-dimensional (3D) brain-like tissue using silkcollagen protein scaffolds seeded with human neurons and endothelial cells. The scaffold design provides compartmentalized control for spatial separation of neurons and endothelial layer, resembling the structure of neurovascular unit. Neurons seeded in a donut-shaped porous silk sponge grow robust neuronal projections within a collagen-filled central region, generating 3D neural networks with structural and functional connectivity. The silk scaffold preserves the mechanical stability of the engineered tissues, allowing for ease of handling, long-term culture in vitro, anchoring of the central collagen gel to avoid shrinkage, neural network maturation and endothelization of vascular compartment. The construct is suitable for perfusion and studies in bioreactor. This study evaluated four human neural cell lines in terms of differentiation potential and capacity to generate neuronal networks using 3D bioengineered cortical brain tissue model, followed by analysis of response to induced ischemic stroke in vitro. The results indicate that due to their robustness, neural stem cells (NSCs) are the most promising source of human neurons for tissue engineering purpose. NSCs readily respond to ischemic conditions both in 2D and 3D, with the extent of response depending on the degree of insult. This 3D model has potential to gain application and recognition in stroke research, as a drug screening tool in preclinical studies and could serve as a foundation for brain-related disease models such as traumatic brain injury. The protocol of construct assembly takes only 2 days and the resulting tissues can be maintained in culture for several weeks. The publications were covered and discussed by media: Statnews, MRS Bulletin, KQED Science. materials360online, ScienceFriday.
Publications
- Bioengineering Brain Matrix Composition to Establish in vitro 3D Physiological Brain Cultures. 4th TERMIS World Congress 2015, 8-11.09 Boston, USA
Chwalek K
- Engineered 3D silk-collagen-based model of polarized neural tissue. J. Vis. Exp 2015 Oct;(104): e52970
Chwalek K, Sood D, Cantley WL, White JD, Tang-Schomer MD, Kaplan DL
(See online at https://doi.org/10.3791/52970) - In vitro bioengineered model of cortical brain tissue. Nature Protocols 2015 Sep;10(9):1362-73
Chwalek K, Tang-Schomer MD, Omenetto FG, Kaplan DL
(See online at https://doi.org/10.1038/nprot.2015.091)
