Ann-Na Cho

Although animal models underpin cardiovascular research, their limited ability to correctly reproduce human-specific cardiac physiology has accelerated the adoption of three-dimensional (3D) human cardiac organoids and engineered heart tissues. Quantitative tracking of the mechanical behaviour of these 3D cultures provides critical insights into contractile dynamics, functional performance, disease phenotypes and pharmacological responses. However, real-time measurement of these properties remains challenging because of complex 3D geometries and subtle forces generated during contraction. Existing approaches are further constrained by low-throughput, arising from requirements for on-sensor cell cultivation, mechanical clamping or labour-intensive optical analysis. Here we introduce a bio-inspired, wireless platform that integrates ultrasensitive silicon cantilevers with a microscale liquid membrane via air-mediated coupling. Air-pressure changes generated by membrane deflection convert organoid contractility into cantilever bending, enabling non-contact, precise and high-throughput quantification of submillinewton contraction forces across multiple 3D cardiac tissues. By eliminating key experimental constraints, this system establishes a scalable framework for drug screening, electrical stimulation studies and disease modelling in human-relevant cardiac platforms.

Glioblastoma (GBM) remains one of the most aggressive brain malignancies, characterized by rapid infiltration, therapeutic resistance, and dismal prognosis. Modeling GBM invasion in physiologically relevant systems has been hindered by the lack of reproducible platforms. Here, we present a bioengineered assembloid (ASM) system that integrates GBM cells encapsulated in self‐degradable 5% oxidized alginate microgel (5OA) with dorsal forebrain organoids (DOs) to recapitulate early tumor‐host interactions during glioblastoma invasion toward the brain. Live‐cell imaging revealed GBM self‐aggregation, leading to increased recruitment and invasion at the DO boundary, accompanied by strong cell‐cell adhesion, nuclear compaction, and the infiltration fronts enriched in SOX2 ⁺ /Vimentin ⁺ tumor populations. Transcriptomic profiling demonstrated upregulation of adhesion, integrin clustering, and mechanosensing‐associated genes, alongside downregulation of neuronal differentiation pathways, indicating a dual invasion and host suppression strategy. Comparative analyses of GBM‐only constructs and DO‐GBM ASMs revealed elevated expression of laminin subunits and enrichment of invasion‐associated pathways, including PI3K‐AKT‐mTOR and TGF‐β signaling, reflecting a shift toward an invasive state at the transcriptomic level. In vivo implantation of ASMs confirmed aggressive GBM infiltration and niche remodeling, highlighting the translational relevance. These findings suggest that it recapitulates the structural, molecular, and functional hallmarks of GBM invasion and tumor‐driven remodeling of the host brain microenvironment.

Three-dimensional (3D) cardiac tissues provide a physiologically relevant model for human heart function and drug testing, yet scalable and real-time assessment of their contractile performance remains difficult. Here, we report a bio-inspired, ultrasensitive (~5 × 10-4 Pa-1), wireless, non-contact platform for multiplexed measurement of milli-Newton contraction forces from 3D organoids and spheroid-like engineered heart tissues (EHT). Optical imaging validation confirms the platform’s ability to monitor 3D cardiac tissue contractility under diverse conditions, including temperature, drug dosing, and electrical stimulation. Unlike conventional approaches, the system does not require on-sensor cell cultivation, complex fabrication processes, labor-intensive optical data processing, and dedicated setups for external mechanical clamping. The non-contact sensing method eliminates stimulation artifacts, enhances reusability, and enable long-term monitoring. Combined with wireless data transmission and multiplexed array design, the Biomechanical Well Plate (BWP) provides a scalable and cost-effective tool for high-throughput disease modeling and pharmacological screening with 3D cardiac tissues.

APOE ε4 is the strongest genetic risk factor for late-onset Alzheimer’s disease (AD), but its contribution to disease pathogenesis remains incompletely understood. Here, we integrate proteomic profiling of plasma, cerebrospinal fluid (CSF), and brain tissue from over 10,000 individuals to define the immune phenotype associated with APOE ε4. We identify a conserved, allele dose-dependent pro-inflammatory immune signature across peripheral and central tissues independent of AD diagnosis. This signature is enriched in adaptive immune cells and white matter-resident glial and vascular cells. It also emerges in patient-derived cortical organoids prior to amyloid-β and tau pathology, supporting a causal, genotype-driven mechanism. Cross-tissue comparisons reveal shared innate and antiviral responses alongside tissue-specific immune signaling. Notably, a 12-week medical ketogenic diet partially reversed the APOE ε4 immune signature. These findings position immune dysregulation as an early and tractable driver of AD risk in APOE ε4 carriers with direct implications for targeted prevention strategies.

Recent advancements in stem cell biology and tissue engineering have revolutionized the field of neurodegeneration research by enabling the development of sophisticated in vitro human brain models. These models, including 2D monolayer cultures, 3D organoids, organ-on-chips, and bioengineered 3D tissue models, aim to recapitulate the cellular diversity, structural organization, and functional properties of the native human brain. This review highlights how these in vitro brain models have been used to investigate the effects of various pathogens, including viruses, bacteria, fungi, and parasites infection, particularly in the human brain cand their subsequent impacts on neurodegenerative diseases. Traditional studies have demonstrated the susceptibility of different 2D brain cell types to infection, elucidated the mechanisms underlying pathogen-induced neuroinflammation, and identified potential therapeutic targets. Therefore, current methodological improvement brought the technology of 3D models to overcome the challenges of 2D cells, such as the limited cellular diversity, incomplete microenvironment, and lack of morphological structures by highlighting the need for further technological advancements. This review underscored the significance of in vitro human brain cell from 2D monolayer to bioengineered 3D tissue model for elucidating the intricate dynamics for pathogen infection modeling. These in vitro human brain cell enabled researchers to unravel human specific mechanisms underlying various pathogen infections such as SARS-CoV-2 to alter blood-brain-barrier function and Toxoplasma gondii impacting neural cell morphology and its function. Ultimately, these in vitro human brain models hold promise as personalized platforms for development of drug compound, gene therapy, and vaccine. Overall, we discussed the recent progress in in vitro human brain models, their applications in studying pathogen infection-related neurodegeneration, and future directions.

Alzheimer’s disease (AD) is a growing global health crisis affecting millions and incurring substantial economic costs. However, clinical diagnosis remains challenging, with misdiagnoses and underdiagnoses being prevalent. There is an increased focus on putative, blood-based biomarkers that may be useful for the diagnosis as well as early detection of AD. In the present study, we used an unbiased combination of machine learning and functional network analyses to identify blood gene biomarker candidates in AD. Using supervised machine learning, we also determined whether these candidates were indeed unique to AD or whether they were indicative of other neurodegenerative diseases, such as Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS). Our analyses showed that genes involved in spliceosome assembly, RNA binding, transcription, protein synthesis, mitoribosomes, and NADH dehydrogenase were the best-performing genes for identifying AD patients relative to cognitively healthy controls. This transcriptomic signature, however, was not unique to AD, and subsequent machine learning showed that this signature could also predict PD and ALS relative to controls without neurodegenerative disease. Combined, our results suggest that mRNA from whole blood can indeed be used to screen for patients with neurodegeneration but may be less effective in diagnosing the specific neurodegenerative disease.

Numerous viruses use specialized surface molecules called fusogens to enter host cells. Many of these viruses, including the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can infect the brain and are associated with severe neurological symptoms through poorly understood mechanisms. We show that SARS-CoV-2 infection induces fusion between neurons and between neurons and glia in mouse and human brain organoids. We reveal that this is caused by the viral fusogen, as it is fully mimicked by the expression of the SARS-CoV-2 spike (S) protein or the unrelated fusogen p15 from the baboon orthoreovirus. We demonstrate that neuronal fusion is a progressive event, leads to the formation of multicellular syncytia, and causes the spread of large molecules and organelles. Last, using Ca ²⁺ imaging, we show that fusion severely compromises neuronal activity. These results provide mechanistic insights into how SARS-CoV-2 and other viruses affect the nervous system, alter its function, and cause neuropathology.

Cortical organoids are 3D structures derived either from human embryonic stem cells or human induced pluripotent stem cells with their use exploding in recent years due to their ability to better recapitulate the human brain in vivo in respect to organization; differentiation; and polarity. Adeno-associated viruses (AAVs) have emerged in recent years as the vectors of choice for CNS-targeted gene therapy. Here; we compare the use of AAVs as a mode of gene expression in cortical organoids; over traditional methods such as lipofectamine and electroporation and demonstrate its ease-of-use in generating quick disease models through expression of different variants of the central gene—TDP-43—implicated in amyotrophic lateral sclerosis and frontotemporal dementia.

Brain organoids derived from human pluripotent stem cells provide a highly valuable in vitro model to recapitulate human brain development and neurological diseases. However, the current systems for brain organoid culture require further improvement for the reliable production of high-quality organoids. Here, we demonstrate two engineering elements to improve human brain organoid culture, (1) a human brain extracellular matrix to provide brain-specific cues and (2) a microfluidic device with periodic flow to improve the survival and reduce the variability of organoids. A three-dimensional culture modified with brain extracellular matrix significantly enhanced neurogenesis in developing brain organoids from human induced pluripotent stem cells. Cortical layer development, volumetric augmentation, and electrophysiological function of human brain organoids were further improved in a reproducible manner by dynamic culture in microfluidic chamber devices. Our engineering concept of reconstituting brain-mimetic microenvironments facilitates the development of a reliable culture platform for brain organoids, enabling effective modeling and drug development for human brain diseases.

Won-Young Choi, Ji-Hyun Hwang, Ann-Na Cho, Andrew J. Lee, Inkyung Jung, Seung-Woo Cho, Lark Kyun Kim, and Young-Joon Kim. Mol. Cells 2020;43:1011-22. https://doi.org/10.14348/molcells.2020.0207