Korea Institute of Brain Science

Rapid and accurate nucleic acid detection at point-ofcare (POC) requires the compact, automatic, user-friendly, and sample-to-answer system. Here, we report a fully integrated and compact all-in-one platform for photothermal cell lysis and RPA-CRISPR/Cas reaction by using photothermal pump and sequential WLED operation. This all-in-one platform allows continuous cell lysis and RPA-CRISPR/Cas reaction under different temperature condition without the physical interconnection of a fluid control system. Furthermore, the real-time fluorescence signals are detected by using FMLA camera. This work will provide a new approach for developing decentralized and automated POC molecular diagnostics.

Gastric cancer research has rapidly progressed due to interdisciplinary advances in stem cell biology and bioengineering. Gastric organoid models, particularly those derived from adult stem cells, have emerged as powerful tools that recapitulate the cellular complexity of the human stomach. This review highlights the development of various gastric organoid platforms, with a specific focus on the convergence of engineering strategies to overcome the limitations of conventional organoid systems. We explore how CRISPR-based functional genomics, matrix innovations, co-culture systems, microphysiological systems (MPS), and big data integration are collectively enhancing organoid models. Furthermore, we examine how artificial intelligence may refine the clinical relevance and precision of gastric organoid models. By assessing both current capabilities and future directions, this review offers a perspective on how gastric organoid systems may reflect human physiology more accurately and improve therapeutic outcomes.

Immunoassays are widely used for preliminary drug screening. While lateral flow assays (LFAs) offer rapid and portable testing, they often suffer from limited sensitivity and subjective interpretation. In contrast, laboratory-based immunoassay systems provide high precision but are unsuitable for field use due to their size and cost. To address these limitations, we developed a portable fluorescence-based microfluidic assay capable of detecting methamphetamine (MET), benzoylecgonine (BE), 11-nor-9-carboxy-tetrahydrocannabinol (THC-COOH), and benzodiazepines (BZOs) in urine specimens within 5 min. They were selected based on both global and domestic prevalence, as well as the detection capability of the developed microfluidic chip, which was designed to simultaneously target all four. The assay comprises a portable reader and a chip with two channels, each aligned with drug-specific antibodies, enabling simultaneous detection. The assay was tested against standard concentrations of the target drugs, delivering accurate test/reference ratios and signal displacements at threshold levels. We evaluated urine specimens (N = 141) provided by the National Forensic Service in Korea, including drug-free controls (N = 30) and cases confirmed for MET (N = 30), THC-COOH (N = 30), and BZOs (N = 13), along with samples from Paraguay for BE (N = 38), using validated diagnostic techniques. Analysis of 141 authentic urine specimens, encompassing verified instances of both single and poly drug use, showed high sensitivity and specificity with minimal cross reactivity. This study confirms that the microfluidic assay is effective in detecting multiple drugs simultaneously, offering high accuracy, cost-effectiveness, and portability, with excellent sensitivity for each drug tested.

Early detection of ultra-low-abundance protein biomarkers is critical for improving clinical outcomes. However, many conventional immunoassays and proteomic platforms exhibit high limits of detection (LOD) and long incubation times, complicating low-to sub-femtomolar measurements. In addition, state-of-the-art digital ELISAs often rely on magnetic beads, oil emulsions, and pump-valve benchtop analyzers-bulky and costly systems that hinder broad deployment. Here, we present a digital ELISA (dELISA) that lowers LOD and shortens time-to-result by harnessing rapid, repeated femtoliter-scale droplet evaporation on a bead-free, oil-free micro-droplet array. Cyclic ≈30-fL droplet generation/evaporation at the air-water interface enriches analytes at antibody-functionalized surfaces, while evaporation-induced convection and a shortened diffusion path increase antigen-antibody encounter frequency. For cardiac troponin I, the platform achieved an LOD of 64.23fM with 300 evaporation cycles, a >280-fold improvement over 96-well ELISA. The same capture obtained after 120min of static soaking occurred in 1.76min with cyclic evaporation. Counts matched a Poisson capture model, with binding increasing linearly with cycle number. In diluted human plasma, the assay maintained >86% recovery with minimal non-specific adsorption. Simple fabrication, the absence of beads, oils, and complex fluidic hardware, and high-throughput compatibility indicate strong potential for point-of-care use and integration into diverse digital immunoassay applications.

Voltage-sensing phosphatases (VSPs) provide a conserved framework for dissecting the mechanics of voltage sensing and for engineering genetically encoded voltage indicators (GEVIs). To evaluate how natural sequence diversity shapes function, we compared VSP voltage-sensing domains (VSDs) from multiple species by replacing the phosphatase domain with a fluorescent protein to enable optical detection of VSD responses. Every construct that reached the plasma membrane produced a voltage-dependent optical signal, underscoring the deep conservation of voltage sensing across VSP orthologs. Yet lineage-specific substitutions generated strikingly different phenotypes. A plankton VSP ortholog from Eurytemora carolleeae and the Sea Hare (Aplysia californica) VSP exhibited left-shifted activation ranges, producing robust fluorescence transitions during modest depolarizations of the plasma membrane. The human VSD of hVSP2 yielded weak, sluggish responses with poor recovery, but reintroduction of a conserved arginine in S1 (G95R) partially restored reversibility, implicating lipid-facing residues in conformational stability. The Chinese hamster (Cricetulus griseus) VSD, with atypical S4 sensing charges (RWIR), generated a slow fluorescence increase during depolarization, while reverting to the consensus arginine (RRIR) inverted the polarity to a decrease. These contrasting behaviors show that single residue changes can reshape how VSD movements influence the fluorescent reporter, highlighting the molecular precision revealed by GEVI measurements. Together, these results show that voltage-dependent signaling is deeply conserved across VSPs but shaped by lineage-specific sequence variation, establishing VSPs as powerful models for probing voltage sensing and guiding GEVI design.

Objective This study aims to investigate the clinical relevance of occipital hypoperfusion in patients with Parkinson’s disease (PD) with respect to clinical phenotype and the risk of dementia conversion.Methods We enrolled 349 patients with newly diagnosed PD and 48 healthy controls who underwent dual-phase 18F-N-(3-fluoropropyl)-2β-carboxymethoxy-3β-(4-iodophenyl) nortropane (18F-FP-CIT) positron emission tomography (PET). Patients with PD were classified into three groups based on posterior cortical perfusion patterns on early-phase 18F-FP-CIT PET images: PD with preserved posterior cortical perfusion (n=186), PD with parieto-temporal hypoperfusion (n=84), and PD with parieto-temporo-occipital hypoperfusion (n=79). Baseline clinical features and dementia conversion risk were compared across PD groups.Results Patients with preserved posterior cortical perfusion were younger than those in the other PD groups. Compared with the other groups, the parieto-temporo-occipital hypoperfusion group tended to have lower Cross-Cultural Smell Identification Test scores, a higher prevalence of rapid eye movement sleep behavior disorder, higher Unified PD Rating Scale motor scores, and more severe reductions in striatal dopamine transporter availability. The risk of dementia conversion was lower in patients with preserved posterior cortical perfusion than in those with posterior cortical hypoperfusion. However, the risk of dementia conversion did not differ between the parieto-temporal and parieto-temporo-occipital hypoperfusion groups.Conclusion Additional occipital hypoperfusion was not associated with an imminent risk of dementia conversion in patients with PD with posterior cortical hypoperfusion. Nonetheless, occipital involvement may serve as an indicator of the diffuse malignant subtype of PD.

The heavy reliance of animal studies on human observers makes them prone to observer-specific biases. To mitigate such shortcomings, much research has been focused on computerizing the characterization of animal behavior. Such automation can lead to more reliable and cost-effective behavior quantifications. Yet, there remain challenges in developing end-to-end solutions that allow users to easily train custom behavioral classifiers with minimal data while maintaining low computational demands. Here we resolve these challenges through a rodent behavior classifier, the real-time rodent behavior classifier using color-based body segmentation (R2C2) algorithm, which uses color-based body segmentation to track rodent body parts and consequently their behaviors. Based on the 'hue, saturation, value' (HSV) color difference in furs or exposed skins, the R2C2 creates simple white-black color boundaries for each body part, which are then used to discern and track body parts in real time to extract movement-based features. We combined wavelet transform-based tracking with HSV color-based body part segmentation to substantially reduce computational requirements while minimizing the number of input features needed for classification. Loading these features into our convolutional neural network algorithm, the R2C2 achieves performance on par with an expert human observer. Furthermore, it can differentiate subtle behavioral patterns associated with autism spectrum disorder in mouse models. As the R2C2 is a complete, lightweight end-to-end pipeline package with a graphical user interface and does not require end-user programming or heavy computation resources, it can be easily adopted in conventional neuroscience laboratories. By enabling effective auto-labeling of fine animal actions, R2C2 will facilitate studies aiming to uncover the neural mechanisms driving behavioral modulations.

Human‐induced pluripotent stem cell (iPSC)‐derived brain organoids have attracted significant attention as promising models for drug screening owing to their remarkable resemblance to the human brain. The advent of disease model organoids, derived from patient's cells, has further elevated expectations for drug screening and personalized medicine. Nevertheless, the absence of a comprehensive platform for administering drugs and assessing their efficacy based on functional changes in brain organoids has remained a challenge. In this study, we introduce a one‐step drug screening system designed designed to investigate functional changes induced by diverse drug doses in multiple brain organoids, utilizing electrophysiological signal measurements. Our system comprises a specialized culture chamber with a microfluidic chip capable of accommodating 10 organoids and delivering varying doses of two drugs to each organoid. Additionally, we integrate a three dimentional microelectrode array (3D MEA) with ten shanks, enabling functional assessment of 10 brain organoids. This approach facilitates dose‐dependent drug screening across multiple organoids. We demonstrate the effectiveness of our system through real‐time analysis of neural activity changes triggered by different doses of pottassium chloride (KCl). Furthermore, sodium channel protein type 2 subunit alpha (SCN2A)‐epileptic organoids to demonstrate utility in disease‐model‐based drug screening. Our platform enables functional screening and personalized medicine using brain organoids.

ABSTRACTNeuroinflammation, predominantly associated with glial activation and the release of various inflammatory mediators, is a vital hallmark of the pathophysiology of epilepsy. Numerous studies have indicated that identifying novel factors that diminish neuroinflammatory processes may be important for developing effective therapeutic strategies to prevent neuropathological processes and epileptogenic progression. Transient receptor potential vanilloid 5 (TRPV5) is a highly selective calcium ion channel belonging to the TRPV family. TRPV5 expression has been identified in diverse regions of the brain; however, it remains unknown how TRPV5 is implicated in the pathophysiological features of neurological diseases, including epilepsy. Herein, we show that TRPV5 expression is upregulated in the hippocampus of a pilocarpine‐induced status epilepticus (PCSE) model, predominantly in activated microglia. Pharmacological inhibition of TRPV5 using econazole attenuated microglial activation, as indicated by the shift of LPS‐stimulated primary hippocampal microglia to a resting state. This inhibition suppressed AKT/NF‐κB signaling, reduced NLRP3 inflammasome activity, and decreased proinflammatory cytokine production. Additionally, TRPV5 inhibition reduced hippocampal microglial activation and neuroinflammation following PCSE. These findings suggest that TRPV5 contributes to the regulation of microglial activation, resulting in the suppression of microglia‐derived neuroinflammation during the sub‐acute phase of epilepsy. In conclusion, the present study suggests that targeting TRPV5 may offer a novel therapeutic approach to managing the neuroinflammatory processes during epileptogenic progression.