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Organoid Intelligence ushers in a new era by seamlessly integrating cutting-edge organoid technology with the power of artificial intelligence. Organoids, three-dimensional miniature organ-like structures cultivated from stem cells, offer an unparalleled opportunity to simulate complex human organ systems in vitro. Through the convergence of organoid technology and AI, researchers gain the means to accelerate discoveries and insights across various disciplines. Artificial intelligence algorithms enable the comprehensive analysis of intricate organoid behaviors, intricate cellular interactions, and dynamic responses to stimuli. This synergy empowers the development of predictive models, precise disease simulations, and personalized medicine approaches, revolutionizing our understanding of human development, disease mechanisms, and therapeutic interventions. Organoid Intelligence holds the promise of reshaping how we perceive in vitro modeling, propelling us toward a future where these advanced systems play a pivotal role in biomedical research and drug development. 

ABSTRACT Introduction:We hypothesized extracellular vesicles (EVs) from preconditioned human-induced pluripotent stem cell–derived mesenchymal stem cells (iMSCs) attenuate LPS-induced acute lung injury (ALI) and endotoxemia.Methods:iMSCs were incubated with cell stimulation cocktail (CSC) and EVs were isolated. iMSC-EVs were characterized by size and EV markers. Biodistribution of intratracheal (IT), intravenous, and intraperitoneal injection of iMSC-EVs in mice was examined using IVIS. Uptake of iMSC-EVs in lung tissue, alveolar macrophages, and RAW264.7 cells was also assessed. C57BL/6 mice were treated with IT/IP iMSC-EVs or vehicle ± IT/IP LPS to induce ALI/acute respiratory distress syndrome and endotoxemia. Lung tissues, plasma, and bronchoalveolar lavage fluid (BALF) were harvested at 24 h. Lung histology, BALF neutrophil/macrophage, cytokine levels, and total protein concentration were measured to assess ALI and inflammation. Survival studies were performed using IP LPS in mice for 3 days.Results:iMSC-EV route of administration resulted in differential tissue distribution. iMSC-EVs were taken up by alveolar macrophages in mouse lung and cultured RAW264.7 cells. IT LPS-treated mice demonstrated marked histologic ALI, increased BALF neutrophils/macrophages and protein, and increased BALF and plasma TNF-α/IL-6 levels. These parameters were attenuated by 2 h before or 2 h after treatment with IT iMSC-EVs in ALI mice. Interestingly, the IT LPS-induced increase in IL-10 was augmented by iMSC-EVs. Mice treated with IP LPS showed increases in TNF-α and IL-6 that were downregulated by iMSC-EVs and LPS-induced mortality was ameliorated by iMSC-EVs. Administration of IT iMSC-EVs 2 h after LPS downregulated the increase in proinflammatory cytokines (TNF-α/IL-6) by LPS and further increased IL-10 levels.Conclusions:iMSC-EVs attenuate the inflammatory effects of LPS on cytokine levels in ALI and IP LPS in mice. LPS-induced mortality was improved with administration of iMSC-EVs. 

Traditionally, tissue-specific organoids are generated as 3D aggregates of stem cells embedded in Matrigel or hydrogels, and the aggregates eventually end up a spherical shape and suspended in the matrix. Lack of geometrical control of organoid formation makes these spherical organoids limited for modeling the tissues with complex shapes. To address this challenge, we developed a new method to generate 3D spatial-organized cardiac organoids from 2D micropatterned human induced pluripotent stem cell (hiPSC) colonies, instead of directly from 3D stem cell aggregates. This new approach opens the possibility to create cardiac organoids that are templated by 2D non-spherical geometries, which potentially provides us a deeper understanding of biophysical controls on developmental organogenesis. Here, we designed 2D geometrical templates with quadrilateral shapes and pentagram shapes that had same total area but different geometrical shapes. Using this templated substrate, we grew cardiac organoids from hiPSCs and collected a series of parameters to characterize morphological and functional properties of the cardiac organoids. In quadrilateral templates, we found that increasing the aspect ratio impaired cardiac tissue 3D self-assembly, but the elongated geometry improved the cardiac contractile functions. However, in pentagram templates, cardiac organoid structure and function were optimized with a specific geometry of an ideal star shape. This study will shed a light on “organogenesis-by-design” by increasing the intricacy of starting templates from external geometrical cues to improve the organoid morphogenesis and functionality. 

Mechanical forces impact cardiac cells and tissues over their entire lifespan, from development to growth and eventually to pathophysiology. However, the mechanobiological pathways that drive cell and tissue responses to mechanical forces are only now beginning to be understood, due in part to the challenges in replicating the evolving dynamic microenvironments of cardiac cells and tissues in a laboratory setting. Although many in vitro cardiac models have been established to provide specific stiffness, topography, or viscoelasticity to cardiac cells and tissues via biomaterial scaffolds or external stimuli, technologies for presenting time-evolving mechanical microenvironments have only recently been developed. In this review, we summarize the range of in vitro platforms that have been used for cardiac mechanobiological studies. We provide a comprehensive review on phenotypic and molecular changes of cardiomyocytes in response to these environments, with a focus on how dynamic mechanical cues are transduced and deciphered. We conclude with our vision of how these findings will help to define the baseline of heart pathology and of how these in vitro systems will potentially serve to improve the development of therapies for heart diseases. 

Abstract Cardioids are 3D self‐organized heart organoids directly derived from induced pluripotent stem cells (hiPSCs) aggregates. The growth and culture of cardioids is either conducted in suspension culture or heavily relies on Matrigel encapsulation. Despite the significant advancements in cardioid technology, reproducibility remains a major challenge, limiting their widespread use in both basic research and translational applications. Here, for the first time, we employed synthetic, matrix metalloproteinase (MMP)‐degradable polyethylene glycol (PEG)‐based hydrogels to define the effect of mechanical and biochemical cues on cardioid development. Successful cardiac differentiation is demonstrated in all the hydrogel conditions, while cardioid cultured in optimized PEG hydrogel (3 wt.% PEG‐2mM RGD) underwent similar morphological development and comparable tissue functions to those cultured in Matrigel. Matrix stiffness and cell adhesion motif play a critical role in cardioid development, nascent chamber formation, contractile physiology, and endothelial cell gene enrichment. More importantly, synthetic hydrogel improved the reproducibility in cardioid properties compared to traditional suspension culture and Matrigel encapsulation. Therefore, PEG‐based hydrogel has the potential to be used as an alternative to Matrigel for human cardioid culture in a variety of clinical applications including cell therapy and tissue engineering. 

Costameres, as striated muscle-specific cell adhesions, anchor both M-lines and Z-lines of the sarcomeres to the extracellular matrix. Previous studies have demonstrated that costameres intimately participate in the initial assembly of myofibrils. However, how costamere maturation cooperates with myofibril growth is still underexplored. In this work, we analyzed zyxin (costameres), α-actinin (Z-lines) and myomesin (M-lines) to track the behaviors of costameres and myofibrils within the cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs). We quantified the assembly and maturation of costameres associated with the process of myofibril growth within the hiPSC-CMs in a time-dependent manner. We found that asynchrony existed not only between the maturation of myofibrils and costameres, but also between the formation of Z-costameres and M-costameres that associated with different structural components of the sarcomeres. This study helps us gain more understanding of how costameres assemble and incorporate into the cardiomyocyte sarcomeres, which sheds a light on cardiomyocyte mechanobiology. 

Tissue morphogenetic remodeling plays an important role in tissue repair and homeostasis and is often governed by mechanical stresses. In this study, we integrated an in vitro mesenchymal tissue experimental model with a volumetric contraction-based computational model to investigate how geometrical designs of tissue mechanical constraints affect the tissue remodeling processes. Both experimental data and simulation results verified that the standing posts resisted the bulk contraction of the tissues, leading to tissue thinning around the posts as gap extension and inward remodeling at the edges as tissue compaction. We changed the geometrical designs for the engineered mesenchymal tissues with different shapes of posts arrangements (triangle vs. square), different side lengths (6 mm vs. 8 mm), and insertion of a center post. Both experimental data and simulation results showed similar trends of tissue morphological changes of significant increase of gap extension and deflection compaction with larger tissues. Additionally, insertion of center post changed the mechanical stress distribution within the tissues and stabilized the tissue remodeling. This experimental-computational integrated model can be considered as a promising initiative for future mechanistic understanding of the relationship between mechanical design and tissue remodeling, which could possibly provide design rationale for tissue stability and manufacturing.