Computational fluid dynamic analysis of physical forces playing a role in brain organoid cultures in two different multiplex platforms

Abstract

Background Organoid cultivation in suspension culture requires agitation at low shear stress to allow for nutrient diffusion, which preserves tissue structure. Multiplex systems for organoid cultivation have been proposed, but whether they meet similar shear stress parameters as the regularly used spinner flask and its correlation with the successful generation of brain organoids has not been determined. Results Here we used computational fluid dynamics (CFD) to simulate two multiplex culture conditions: steering plates on an orbital shaker and the use of a previously described bioreactor. The bioreactor had low speed and high shear stress regions that may affect cell aggregate growth, depending on volume, whereas the computed variables of the steering plates were closer to those of the spinning flask. Conclusion Our protocol improves the initial steps of the standard brain organoid formation, and the produced organoids displayed regionalized brain structures, including retinal pigmented cells. Overall, we conclude that suspension culture on orbital steering plates is a cost-effective practical alternative to previously described platforms for the cultivation of brain organoids for research and multiplex testing. Electronic supplementary material The online version of this article (10.1186/s12861-019-0183-y) contains supplementary material, which is available to authorized users.

d-Lysergic acid diethylamide has major potential as a cognitive enhancer

“…Brain organoids generated from human iPSCs were grown in agitation and used for the experiments at day 45, when they already express most of the transcription factors and a protein profile consistent with differentiated brain regions (28). Organoids were treated for 24 h with 10 nM d-LSD and processed by mass spectrometry-based proteomics in order to systematically approach the lysergic effects in human neural cells.…”

“…iPSCs were maintained with mTeSR1 medium and upon confluence passaged manually or with EDTA. iPSC cultures with no differentiated cells were used to prepare brain organoids following a previously described protocol (28). Shortly, iPSCs were detached using Accutase for 5 min at 37°C, detached cells were then added to phosphate-buffered saline (PBS; LGC Biotechnology, USA) containing 10µM ROCK inhibitor (ROCKi, Y27632; Merck Millipore, USA) to a final concentration of 10 μM and dissociated to single cells.…”

Human iPSC-Based Modeling of Central Nerve System Disorders for Drug Discovery

“…Cerebral organoids, also known as ‘mini brains’, reproduce fetal brain development and therefore serve as a powerful platform to study human development and CNS diseases. Self-organization during organoid differentiation generates complex and discrete anatomic regions resembling the human brain, including the dorsal cortex, ventral forebrain, retina, hippocampus, choroid plexus, and midbrain–hindbrain boundary [ 21 , 22 ]. Kadoshima et al report forebrain-like structures in neural embryoid bodies (EB), in which basal progenitors in the outer subventricular zone of the self-formed 3D cortical neuroepithelium are similar to the outer radial glia found in the human brain [ 23 ].…”

“…For example, by fusing dorsal and ventral forebrain organoids, researchers establish a dorsal-ventral axis to reveal GABAergic interneuron migration and integration along the axis [ 28 , 29 ]. A low-shear stress has also played an increasingly important role in EB-to-organoid differentiation because the fluid dynamics in a spin-culture system not only promotes nutrient diffusion but also maximizes pluripotent stem cell propagation by keeping cell aggregates below the critical size of a diffusion limit [ 22 , 30 ]. Meanwhile, Pasca et al have developed human cortical spheroids (hCSs), a cerebral organoid model that embodies gliogenesis and neurogenesis [ 31 , 32 , 33 ].…”

Retinal Organoids On-a-Chip: A 3D Printed Micro-Millifluidic Bioreactor for Long-Term Retinal Organoid Maintenance

“…This heterogeneity and imprecision limit human RtOg procurement for preclinical trials 26 and in vitro investigations. Many approaches, including bioreactors [28][29][30][31][32][33][34] and optimized production protocols 26,35 are investigated to standardize RtOg production and maintenance over months. Controlled and predictable RtOg production is important to ensure a quality-controlled tissue product that is suitable for transplantation.…”