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Over the last decade, scientists have begun to model CNS development, function, and disease in vitro using human pluripotent stem cell (hPSC)-derived organoids. Using traditional protocols, these 3D tissues are generated by combining the innate emergent properties of differentiating hPSC aggregates with a bioreactor environment that induces interstitial transport of oxygen and nutrients and an optional supportive hydrogel extracellular matrix (ECM). During extended culture, the hPSC-derived neural organoids (hNOs) obtain millimeterscale sizes with internal microscale cytoarchitectures, cellular phenotypes, and neuronal circuit behaviors mi-metic of those observed in the developing brain, eye, or spinal cord. Early studies evaluated the cytoarchitectural and phenotypical character of these organoids and provided unprecedented insight into the morphogenetic processes that govern CNS development. Comparisons to human fetal tissues revealed their significant simila-rities and differences. While hNOs have current disease modeling applications and significant future promise, their value as anatomical and physiological models is limited because they fail to form reproducibly and re-capitulate more mature in vivo features. These include biomimetic macroscale tissue morphology, positioning of morphogen signaling centers to orchestrate appropriate spatial organization and intra- and inter-connectivity of discrete tissue regions, maturation of physiologically relevant neural circuits, and formation of vascular net-works that can support sustained in vitro tissue growth. To address these inadequacies scientists have begun to integrate organoid culture with bioengineering techniques and methodologies including genome editing, bio-materials, and microfabricated and microfluidic platforms that enable spatiotemporal control of cellular differentiation or the biochemical and biophysical cues that orchestrate organoid morphogenesis. This review will examine recent advances in hNO technologies and culture strategies that promote reproducible in vitro morphogenesis and greater biomimicry in structure and function.
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This content will become publicly available on November 1, 2026
Morphogen Patterning in Dynamic Tissues
Embryogenesis integrates morphogenesis—coordinated cell movements—with morphogen patterning and cell differentiation. While largely studied independently, morphogenesis and patterning often unfold simultaneously in early embryos. Yet how cell movements affect morphogen transport and cells' exposure over time remains unclear, as most pattern formation models assume static tissues. Here we develop a theoretical framework for morphogen patterning in dynamic tissues, recasting advection-reaction-diffusion equations in the cells' moving reference frames. This framework (i) elucidates how morphogenesis mediates morphogen transport and compartmentalization: cell-cell diffusive transport is enhanced at multicellular flow attractors, while repellers act as barriers, affecting cell fate induction and bifurcations. (ii) It formalizes cell-cell signaling ranges in dynamic tissues, deconfounding morphogenetic movements to identify which cells could communicate via morphogens. (iii) It provides two new nondimensional numbers to assess when and where morphogenesis affects morphogen transport. We demonstrate this framework by analyzing classical patterning models with common morphogenetic motifs as well as experimental tissue flows. Our work rationalizes dynamic tissue patterning in development, constraining candidate patterning mechanisms and parameters using accessible cell motion data.
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- PAR ID:
- 10650546
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- PRX Life
- Volume:
- 3
- Issue:
- 4
- ISSN:
- 2835-8279
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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