Tissue‐engineered in vitro modeling of the impact of Schwann cells in amyotrophic lateral sclerosis

Abstract

Amyotrophic Lateral Sclerosis (ALS) is a devastating neurodegenerative disease affecting upper and lower motor neurons (MNs). To investigate whether Schwann cells could be involved in the disease pathogenesis, we developed a tissueengineered three-dimensional (3D) in vitro model that combined MNs cocultured with astrocytes and microglia seeded on top of a collagen sponge populated with epineurium fibroblasts to enable 3D axonal migration. C2C12 myoblasts were seeded underneath the sponge in the presence or absence of Schwann cells. To reproduce an ALS cellular microenvironment, MNs, astrocytes, and microglia were extracted from SOD1 G93A mice recapitulating many aspects of the human disease.

In Vitro Characterization of Motor Neurons and Purkinje Cells Differentiated from Induced Pluripotent Stem Cells Generated from Patients with Autosomal Recessive Spastic Ataxia of Charlevoix-Saguenay

“…We showed for the first time that it was possible to differentiate ARSACS-iPSCs into MNs and Purkinje cells using the 3D culture system we developed, as well as to detect some characteristic ARSACS pathological features such as abnormal accumulation of NFM along the neurites. Using collagen sponges populated with dermal fibroblasts as a 3D substrate, which is known to promote long-term survival and neurite elongation of MNs [ 39 ] and to reproduce pathological features observed in other brain diseases such as neurofibromatosis [ 46 ] and amyotrophic lateral sclerosis [ 47 , 48 ], it was possible to enable long term (>53 days) of Purkinje cells and to promote abundant elaborated dendritic ramifications. To better mimic ARSACS cellular microenvironment around MNs, iPSC-derived Schwann cells were also cocultured with iPSC-MNs within the 3D substrate.…”

“…To better mimic ARSACS cellular microenvironment around MNs, iPSC-derived Schwann cells were also cocultured with iPSC-MNs within the 3D substrate. Such condition allowing the coculture of Schwann cells with iPSC-derived MNs was previously shown to be essential to enhance axonal migration and to promote myelin sheath formation around neurites [ 39 , 48 ].…”

In Vitro 3D Modeling of Neurodegenerative Diseases

“…Hydrogels are a network of natural polymers (agarose, collagen, silk, chitosan, gelatin, Matrigel TM , etc. ), synthetic polymers (PEG, polyvinyl acetate), or both, with high versatility, good hydrophilicity, and low toxicity [6,85]. Since natural polymers do not have strong mechanical properties, they can be combined with synthetic polymers for increased strength.…”

“…In vitro studies oriented on the cells involved in neurodegenerative diseases have enabled researchers to focus on close interactions between cells (such as neurons, astrocytes, microglia, and oligodendrocytes), to better understand the disease mechanism at the cellular and molecular levels. In addition, these in vitro culture systems allow researchers to co-culture together (in various combinations) diseased or healthy cells to more accurately determine which cell type causes or aggravates the pathology [6]. Many studies have turned to in vitro two-dimensional (2D) monolayer cell culture and, more recently, studies using three-dimensional (3D) cell culture models.…”

“…Thanks to a more complex and adjustable physiological environment that combines together ECM with various cell types, the use of 3D cell culture models is growing, and brings additional responses to in vivo studies. A variety of neurodegenerative disease models have been developed (using a scaffold-based approach, spheroid, or organoid techniques) and have demonstrated control over cell organization in some models, and flexibility regarding ECM material selection for others [6,[11][12][13][14][15]. However, a deficiency in both nutrient/oxygen supply and waste elimination were often some of the limitations pointed out when using these engineer-based models.…”