Katsuo Kurabayashi

Patients with critical illness often exhibit profound biological heterogeneity, complicating the identification of effective interventions. Resolving distinct molecular profiles to enable timely treatment decisions remains challenging, as integrating biomarker-guided care into routine monitoring is often hindered by fragmented, batch-based workflows. These manual operations decouple molecular data from the acute clinical timeline and are a barrier to reliable, real-time, near to patient, multi-center implementation. To address this gap, we developed an integrated microfluidic digital immunoassay system that achieves high analytical fidelity through a fully automated, simple workflow. The system utilizes a monolithic disposable cartridge to automate bead-based analyte capture, oil-phase partitioning, and signal amplification, eliminating the manual handling and emulsion steps that typically compromise digital assay robustness. The platform enables protein measurement within 45 minutes, achieving sub-picogram limit of detection ( < 0.13 pg/mL), a dynamic range spanning three orders of magnitude, and strong analytical reproducibility. We demonstrate the clinical utility of the system by profiling a validated panel of inflammatory biomarkers in plasma from critically ill pediatric patients, using low sample volumes. Results show strong agreement with gold-standard multiplex assays (R2 = 0.925-0.979). By providing a scalable framework for high-fidelity molecular profiling, this system supports the broader goal of accessible, multi-center biomarker validation and the practical implementation of precision medicine in critical care.

Rehabilitation after stroke, ligament injury, or neuromuscular disorders requires repetitive, precise, and safe movement training-conditions that are difficult to maintain with traditional clinic-based systems that are bulky and therapist-dependent. This study presents a Flat Inflatable Hydraulic Artificial Muscle (fiHAM) actuator integrated into a wearable lower-limb rehabilitation device designed to provide compact, high-force, and adaptive motion assistance. The fiHAM actuator is fabricated from biaxially oriented polypropylene (BOPP) film pouches that are heat-sealed using a custom G-code pattern and filled with water as an incompressible hydraulic fluid. This design enables a force density up to 2.3 × greater and a response speed 40% faster than comparable pneumatic artificial muscles. Bench experiments demonstrated blocked forces exceeding 180 N, stroke lengths up to 30 mm, and repeatability within ±3% over more than 50 actuation cycles. Integrated with a lightweight body-weight support (BWS) module, the wearable device can unload 20-30% of a user's body weight, reducing lower-limb stress during assisted gait. Intitial testing confirmed smooth torque generation, accurate angular tracking within ±0.6°, and no detectable leakage under continuous operation. Compared to pneumatic soft actuators, the fiHAM system achieved higher stiffness, faster response, and improved payload performance while remaining lightweight and portable. This work demonstrates a low-cost and scalable manufacturing process using printable polymer films and programmable heat-sealing, offering a practical path toward personalized, hydraulically actuated rehabilitation devices. The proposed system bridges the gap between laboratory prototypes and real-world wearable therapy solutions, enabling continuous, safe, and adaptive at-home rehabilitation with clinical-grade precision.

Vaccines have revolutionized public health, yet their development remains hampered by the poor predictive power of animal models, leading to high clinical failure rates and variable efficacy across populations. To bridge this translational gap, we developed a human lymph node-on-a-chip model that biomimetically reproduces key physiological features of human lymph node, including compartmentalized immune cell zones and functional stromal networks. This immunocompetent model recapitulates the complete cascade of vaccine-induced adaptive immune processes in human lymph nodes, from antigen presentation, immune cell differentiation to germinal center formation and antibody secretion, providing a human-relevant platform for preclinical vaccine testing. Using donor-matched immune cells from influenza vaccine trials, we established a personalized clinical-trial-on-chip platform that accurately mirrors individual vaccine responses. Benchmarking on-chip immunogenicity readouts against clinical serological and transcriptomic data confirmed the platform’s predictive power for assessing vaccine efficacy across diverse populations. Our study uncovered a key mechanism of vaccine failure in vulnerable populations: age- and comorbidities-related factors impair T follicular helper cell differentiation and disrupt critical T-B cell interactions. Single-cell transcriptomic profiling revealed critical immune signaling networks involving MyD88 in DCs, IL-2/STAT5 balance in T cells, and TACI/BCMA activation in B cells that collectively govern the efficiency of the adaptive immune cascade. These mechanistic insights enabled us to validate clinically actionable strategies, including dose escalation and IL-2 cytokine adjuvant as effective countermeasures to enhance immunogenicity efficiency in immunocompromised individuals. These results demonstrate the potential of this human lymph node-on-a-chip as a transformative precision vaccinology tool for personalized vaccine immunogenicity assessment and optimization.

Concrete is the second most consumed material globally, and Portland cement production contributes about 8% of CO 2 emissions, emphasizing the need for developing low-carbon binders for structural and additive manufacturing applications. This study proposes a standardized approach for evaluating geopolymer concrete (GPC) mix designs using a preset binder combined with industrial and agricultural waste.Crushed and uncalcined rice husk powder was incorporated to reduce embodied energy and density while assessing its effects on reactivity and performance. Compressive strength testing, Scanning electron Microscope (SEM) , and energy-dispersive X-ray spectroscopy (EDS) analyses were used on precursor and cured samples to examine mechanical behavior and microstructural features. The mixture containing Uncalcined Rice Husk, industrial waste, and water achieved the highest compressive strength (30.45 MPa). Results demonstrate that combining industrial waste with rice husk can produce high-strength, low-carbon GPC composites suitable for additive manufacturing and construction.

CAR T cell cytotoxicity requires generating immense mechanical force, but the energetic costs of this process remain poorly defined. While metabolic reprogramming fuels effector function, its mechanistic connection to mechanotransduction remains unclear. By directly measuring the synaptic force and mechanical energy of single CAR T cells and linking them to their metabolic state, we proved that the mechano-energetic efficiency is a fundamental determinant of cytotoxic potency. We discovered that the mechanosensitive ion channel Piezo1 couples cytoskeletal dynamics to metabolic rewiring via Ca2+-Wnt-Rac1 signaling. Disrupting Piezo1 cripples glycolytic and mitochondrial ATP production, causing energetic stress and impaired cytotoxicity. Notably, Piezo1 activity follows a Goldilocks principle: intermediate level maximizes activation and cytotoxicity, whereas either hypoactive or hyperactive Piezo1 states impair mechano-metabolic fitness and drive dysfunction in patient and exhausted CAR T cells. Our work establishes mechano-metabolic coupling as a core regulator of CAR T cell fitness and pinpoints Piezo1 tuning as a new strategy to enhance cancer immunotherapy.

Protein secretion plays a crucial role in cell-to-cell communication, tissue homeostasis, and disease progression. Mapping secretomes from paired cells provides valuable insights into their interactions; however, existing approaches yield only semi-quantitative, endpoint data, lacking real-time and quantitative resolution. Herein, real-time spatiotemporal imaging of extracellular secretions from individual cells using a high-throughput integrative biosensing nanoplasmonic array (iBNA) within microfluidics is presented. The self-assembled iBNA, composed of precisely arranged gold nanostructures functionalized with aptamer receptors, enhances plasmonic resonance and significantly improves the spatiotemporal resolution and specificity of interleukin-6 (IL-6) imaging, surpassing conventional techniques. The iBNA's molecular recognition mechanism exploits biomolecular surface binding-induced localized plasmonic resonance shifts, correlating with cytokine concentration and enabling optoelectronic detection of transmitted light. Using iBNA, spatiotemporal resolution images of polarized cytokine-mediated cell-to-cell communication between Jurkat T cells and CD4+ T cells, which are essential to immune responses, are achieved. This transformative platform provides unprecedented insights into the spatiotemporal dynamics of protein secretion, offering significant potential for immunological research, cellular biology, and diagnostic applications in infectious diseases.

Abstract Maintaining blood glucose within a physiologically safe range is critical for people with diabetes, as deviations can lead to acute or chronic complications. Hypoglycemia, in particular, represents an immediate threat and requires prioritized mitigation in autonomous insulin delivery systems. This paper introduces a risk-aware hybrid nonlinear model predictive control (NMPC) framework that combines data-driven uncertainty quantification with formal safety assurance through control barrier functions (CBFs). To account for key uncertainties, such as physiological time delays, unannounced meals, and stress-induced glucose variability, Gaussian processes (GPs) are employed as probabilistic estimators. The proposed method dynamically monitors glucose and regulates insulin injection to enforce safe glucose level control by preventing hypoglycemia. The proposed framework is evaluated using validated physiological simulators for various realistic scenarios. The results show a robust performance in maintaining safety under high uncertainty, preparing a foundation for translation into next phase of our research as safe autonomous diabetes management systems.

Collaborative robots (cobots) increasingly operate alongside humans, demanding robust real-time safeguarding. Current safety standards (e.g., ISO 10218, ANSI/RIA 15.06, ISO/TS 15066) require risk assessments but offer limited guidance for real-time responses. We propose a virtual fencing approach that detects and predicts human motion, ensuring safe cobot operation. Safety and performance trade-offs are modeled as an optimization problem and solved via sequential quadratic programming. Experimental validation shows that our method minimizes operational pauses while maintaining safety, providing a modular solution for human-robot collaboration.

Citrullinated histone H3 (CitH3), released from immune cells during early sepsis, drives a vicious cycle of inflammation through excessive NETosis and pyroptosis, causing immune dysfunction and tissue damage. To regulate this process, we develop a humanized CitH3 monoclonal antibody (hCitH3-mAb) with high affinity and specificity to target this process. In murine models, hCitH3-mAb reduces cytokine production, mortality and acute lung injury (ALI) caused by LPS and Pseudomonas aeruginosa while enhancing bacteria phagocytosis in the lungs, spleen, and liver. Using pre-equilibrium digital ELISA (PEdELISA), we identify an optimal therapeutic window for hCitH3-mAb in sepsis-induced ALI. In parallel, we explore the molecular mechanism underlying CitH3-driven inflammation. We find that in macrophages, CitH3 activates Toll-like receptor 2 (TLR2), triggering Ca2+-dependent PAD2 auto-citrullination and nuclear translocation, amplifying CitH3 production via a harmful feedback loop. The hCitH3-mAb treatment effectively disrupts this cycle and restores macrophage function under septic conditions. Together, these findings highlight both the therapeutic potential of hCitH3-mAb and provide a deep mechanistic insight into the CitH3–PAD2 axis in sepsis, supporting its further development for treating immune-mediated diseases. This study reports the development and preclinical evaluation of a humanized citrullinated histone H3 (CitH3) monoclonal antibody that mitigates inflammation, restores macrophage function, and protects against sepsis-induced pulmonary injury.

Time-course monitoring of blood biomarkers with rapid turnaround has the potential to revolutionize the diagnosis, stratification of phenotypes, and therapeutic/prognostic approaches for various acute inflammatory diseases in both clinical and preclinical studies. Current approaches, however, are hampered by slow turnaround times and large sample volume requirements, limiting the exploration of disease mechanisms and therapeutic strategies. Here, we developed a microfluidic digital ELISA platform prototype, combining single-molecule counting with whole blood assay capability for the first time from small animal models. This platform is semi-automated and enables repeated, rapid biomarker monitoring with just 3.5 μL of whole blood collected from the tail. Our platform demonstrated high sensitivity and multiplexity, allowing real-time cytokine profiling within a 2-hour turnaround. Using a murine sepsis model, we achieved precise temporal monitoring of cytokine levels, demonstrating prognostic capability by correlating early-stage cytokine levels with a liver-injury biomarker. This microfluidic platform enables high temporal resolution and rapid monitoring of biomarker dynamics in a single mouse using freshly collected whole blood, significantly reducing the number of animals needed for preclinical studies. This technology has strong potential to transform ICU therapeutic strategies and preclinical research, enabling personalized treatment based on real-time biomarker profiles.

Abstract Protein secretion underpins diverse physiological processes in cell-to-cell communication, tissue homeostasis, and the onset of diseases. Mapping the secretomes from paired cells provides avenues for understanding their interactions. However, prevailing approaches yield only semi-quantitative endpoint data, lacking real-time and quantitative information. Here, we present real time spatiotemporal imaging of extracellular secretions from individual cells via a high-throughput integrative biosensing nanoplasmonic array (iBNA) with a microfluidic chamber. The self-assembled iBNA, composed of precisely arranged gold nanostructures and functionalized with aptamer receptors, enhances plasmonic resonance and significantly improves the spatiotemporal resolution and specificity of interleukin-6 (IL-6) imaging, surpassing gold-standard techniques. The molecular recognition of iBNA, and sensing mechanism exploits biomolecular surface binding-induced localized plasmonic resonance shifts, correlating with cytokine concentration and enabling optoelectronic detection of the transmitted light. Using this approach, we achieve spatiotemporally resolved visualization of IL-6 secretion dynamics at the single-cell level and unveil the temporal and polarized variation of cell-cell communications. This transformative platform holds significant potential to advance immunological research, cellular biology, and diagnostic applications for infectious diseases by enabling unprecedented insights into the spatiotemporal patterns of protein secretion in individual cells.

Time-course monitoring of blood biomarkers with rapid turnaround has the potential to revolutionize the diagnosis, stratification of phenotypes, and therapeutic/prognostic approaches for various acute inflammatory diseases in both clinical and preclinical studies. Current approaches, however, are hampered by slow turnaround times and large sample volume requirements, limiting the exploration of disease mechanisms and therapeutic strategies. Here, we developed a microfluidic digital ELISA platform prototype, combining single-molecule counting with whole blood assay capability for the first time from small animal models. This platform is automated and enables repeated, rapid biomarker monitoring with just 3.5 μL of whole blood collected from the tail. Our platform demonstrated high sensitivity and multiplexity, allowing real-time cytokine profiling within a 2-hour turnaround. Using a murine sepsis model, we achieved precise temporal monitoring of cytokine levels, demonstrating prognostic capability by correlating early-stage cytokine levels with a liver-injury biomarker. This microfluidic platform enables high temporal resolution and rapid monitoring of biomarker dynamics in a single mouse using freshly collected whole blood, significantly reducing the number of animals needed for preclinical studies. This technology has strong potential to transform ICU therapeutic strategies and preclinical research, enabling personalized treatment based on real-time biomarker profiles.

Inflammation is the body’s response to infection, trauma or injury and is activated in a coordinated fashion to ensure the restoration of tissue homeostasis and healthy physiology. This process requires communication between stromal cells resident to the tissue compartment and infiltrating immune cells which is dysregulated in disease. Clinical innovations in patient diagnosis and stratification include measures of inflammatory activation that support the assessment of patient prognosis and response to therapy. We propose that (i) the recent advances in fast, dynamic monitoring of inflammatory markers (e.g., cytokines) and (ii) data-dependent theoretical and computational modeling of inflammatory marker dynamics will enable the quantification of the inflammatory response, identification of optimal, disease-specific biomarkers and the design of personalized interventions to improve patient outcomes - multidisciplinary efforts in which biomedical engineers may potentially contribute. To illustrate these ideas, we describe the actions of cytokines, acute phase proteins and hormones in the inflammatory response and discuss their role in local wounds, COVID-19, cancer, autoimmune diseases, neurodegenerative diseases and aging, with a central focus on cardiac surgery. We also discuss the challenges and opportunities involved in tracking and modulating inflammation in clinical settings.

Abstract Rationale: The trajectory and stability of inflammatory subphenotypes in critically ill patients are poorly understood. Current measurement technologies face significant limitations for performing high frequency, low sample volume, reproducible and near-to-patient quantification of immune molecules. Digital ELISA technology promises to overcome many of these barriers, but current commercial and laboratory-based systems incur significant costs related to stringent demands for manufacturing and reagent handling. These costs are largely related to the need for microwell structures that allow physical confinement and detection of individual antigen/antibody binding. Replacing physical methods with chemical methods of confinement and amplification would greatly improve digital immunoassay manufacturability, cost, and accessibility. Methods: We have developed a multiplex digital immunosensor that employs linkage of capture antibodies to a planar substrate, followed by antigen and detection antibody incubation and visualization of sandwich immunocomplexes using tyramide-conjugated fluorophores. The assay is implemented in a semi-automated flow cell format. The output image is read using an epifluorescence microscope. We conducted a proof-of concept and feasibility demonstration with twice daily measurements of 5 cytokines in whole capillary blood following influenza and COVID-19 vaccination from a single subject. Results: The tyramide based immunosensor produces a digital immunoassay result, in which the number of immunoreactive puncta, but not their fluorescent intensity, is log-linearly correlated to analyte concentration with a 4 order of magnitude dynamic range. In a multiplex panel including IL-6, IL-8, sTNFR1, CCL11 and NGAL, less than 10% cross reactivity was observed. Immunosensors were manufactured and preserved using standard protein microarray preservation techniques, allowing on-demand use for serial measurements. In our proof-of-concept demonstration, 8 measurements were made in real time from whole capillary blood over 4 days, with a 2 hour sample to answer time. We observed marked elevations of IL-6, IL-8, and CCL-11 following immunization. These elevations did not occur simultaneously, however, and each were only present at a single time point in our measurements. Conclusions: Tyramide based immunocomplex detection can be leveraged to produce a digital immunosensor that overcomes barriers in manufacturability and cost that limit access to digital immunoassay technology in acute care research. Our proof of concept demonstration showed that cytokine expression is highly dynamic, and that single timepoint sampling is inadequate to capture the response to an immune challenge. We are initiating a pilot study of serial cytokine analysis from capillary blood in ICU patients.

Therapy for PA-Induced Acute Lung Injury In article number 2413253, Xin Yu, Yujing Song, Katsuo Kurabayashi, Yongqing Li, and co-workers discover a new chemical modification site catalyzed by an enzyme called PAD2 on the intracellular protein, NF-κB p65, which modulates immune cell (macrophage) functions. Using nanoparticle therapy to block PAD2 significantly reduced inflammation and improved outcomes in acute lung injury during bacterial infections.

Mediating protein citrullination, peptidyl arginine deiminase 2 (PAD2) has recently been reported to influence macrophage phenotypes. However, the mechanisms of PAD2 on macrophage function in Pseudomonas aeruginosa (PA)-induced acute lung injury syndrome (ALI) remains unclear. Utilizing single-cell RNA sequencing and mass spectrometry-based proteomics, a new citrullination site at arginine 171 (R171) is discovered within nuclear factor- κB (NF-κB) p65 catalyzed by PAD2, which modulates PAD2-NF-κB p65-importin α3 pathway and its downstream M1/M2 macrophage polarization. Building on these findings, a cell-specific targeted therapeutic strategy using gold nanoparticles (AuNPs) conjugated with a novel PAD2 inhibitor, AFM41a, and an intercellular adhesion molecule-1 (ICAM-1) antibody is developed. This approach enables the selective delivery of the inhibitor to M1-polarized macrophages in the PA-infected alveolar niche. In vivo, this nanomedicine reduces excessive inflammation and promotes M1-to-M2 polarization to inhibit ALI. This study highlights the role of PAD2-mediated citrullination in macrophage polarization and introduces a promising nanoparticle-based therapy for PA-induced ALI.

Many cancer therapies fail in clinical trials despite showing potent efficacy in preclinical studies. One of the key reasons is the adopted preclinical models cannot recapitulate the complex tumor microenvironment (TME) and reflect the heterogeneity and patient specificity in human cancer. Cancer-on-a-chip (CoC) microphysiological systems can closely mimic the complex anatomical features and microenvironment interactions in an actual tumor, enabling more accurate disease modeling and therapy testing. This review article concisely summarizes and highlights the state-of-the-art progresses in CoC development for modeling critical TME compartments including the tumor vasculature, stromal and immune niche, as well as its applications in therapying screening. Current dilemma in cancer therapy development demonstrates that future preclinical models should reflect patient specific pathophysiology and heterogeneity with high accuracy and enable high-throughput screening for anticancer drug discovery and development. Therefore, CoC should be evolved as well. We explore future directions and discuss the pathway to develop the next generation of CoC models for precision cancer medicine, such as patient-derived chip, organoids-on-a-chip, and multi-organs-on-a-chip with high fidelity. We also discuss how the integration of sensors and microenvironmental control modules can provide a more comprehensive investigation of disease mechanisms and therapies. Next, we outline the roadmap of future standardization and translation of CoC technology toward real-world applications in pharmaceutical development and clinical settings for precision cancer medicine and the practical challenges and ethical concerns. Finally, we overview how applying advanced artificial intelligence tools and computational models could exploit CoC-derived data and augment the analytical ability of CoC.

Sepsis-induced acute lung injury (ALI) is prevalent in patients with sepsis and has a high mortality rate. Peptidyl arginine deiminase 2 (PADI2) and PADI4 play crucial roles in mediating the host's immune response in sepsis, but their specific functions remain unclear. Our study shows that Padi2-/- Padi4-/- double KO (DKO) improved survival, reduced lung injury, and decreased bacterial load in Pseudomonas aeruginosa (PA) pneumonia-induced sepsis mice. Using single-cell RNA-Seq (scRNA-Seq), we found that the deletion of Padi2 and Padi4 reduced the Nlrp3+ proinflammatory macrophages and fostered Chil3+ myeloid cell differentiation into antiinflammatory macrophages. Additionally, we observed the regulatory role of the NLRP3/Ym1 axis upon DKO, confirmed by Chil3 knockdown and Nlrp3-KO experiments. Thus, eliminating Padi2 and Padi4 enhanced the polarization of Ym1+ M2 macrophages by suppressing NLRP3, aiding in inflammation resolution and lung tissue repair. This study unveils the PADIs/NLRP3/Ym1 pathway as a potential target in treatment of sepsis-induced ALI.

Device researchers have been actively developing novel diagnostic biosensors using metallic nanoparticle-based plasmonic immunoassays.[1] In these biosensing devices, photodetectors with high photoresponsivity and low internal noise levels are integrated to detect the marginal optical signals change induced by biomarker binding events (i.e., Antigen-antibody binding). Recently, atomically thin layers of molybdenum disulfide (MoS 2 ) have been integrated with plasmonic components to enable fast and sensitive colorimetric monitoring of disease-related biomarkers.[2] However, such biosensors are mostly operated in the ultraviolet/visible range, which needs a purification step to separate out a variety of unwanted biomaterials that absorb visible light and takes several hours of preparation steps. Thus, it would be amenable to develop biosensors for biomolecular detections or immunoassays in the whole blood (WB) analytes without any sample preparations.[3] To address the issues mentioned above, recent studies have demonstrated the engineered gold nanoparticles (AuNPs) that have localized surface plasmonic resonance (LSPR) shift around near-infrared (NIR) wavelength region. However, a high-sensitivity photodetector under NIR region is still required to detect marginal signal changes due to the target biomarker binding events. Meanwhile, the MoS 2 material has been reported to exhibits superior photo-response characteristics.[4] MoS 2 is a transition metal dichalcogenide material of which single- and multi-layer films exhibit an efficient electron-hole pair generation rate under photoexcitation and therefore high photo absorption as compared to silicon. Therefore, a systematical study on MoS 2 photoconductors to optimize the optoelectronic properties under near-infrared (NIR) (λ = 650 nm) operation can enable zero-preparation WB immunoassays combined with specially engineered AuNPs. In this work, we study the photo-response properties (i.e., Photoresponsivity spectrum) of in-plane MoS 2 photodetectors as the function of their geometric dimensions and fabrication conditions. Recent study shows that an annealing temperature after exfoliation can etch the upper layers of MoS2 flakes and clean stains on the device and therefore improve device performances (e.g., mobility). [5] This work enables the NIR operation capabilities of plasmonic colorimetric biosensing by introducing the optimized MoS 2 photodetector fabrication practice. This approach reduces assay preparation times and mitigate background interference even with WB analytes and thereby enable the WB point-of-care immunoassays. References [1] Zhou, W., Gao, X., Liu, D. and Chen, X., Chemical reviews, 115(19), pp.10575-10636. (2015). [2] Park, Y., Ryu, B., Deng, Q., Pan, B., Song, Y., Tian, Y., Alam, H.B., Li, Y., Liang, X. and Kurabayashi, K., Small, 16(1), p.1905611 (2020). [3] Wang, Y., Qian, W., Tan, Y. and Ding, S., 23(7), pp.1166-1170. (2008). [4] Britnell, L., Ribeiro, R. M., Eckmann, A., Jalil, R., Belle, B. D., Mishchenko, A., ... &amp; Novoselov, K. S. Science, 340(6138), 1311-1314. (2013). [5] Islam, A., Lee, J. and Feng, P.X.L., Journal of Applied Physics, 123(2), p.025701. (2018). [6] Lu, X., Utama, M. I. B., Zhang, J., Zhao, Y., &amp; Xiong, Q., Nanoscale, 5(19), 8904-8908. (2013).

ABSTRACT: Sepsis is a common, heterogeneous, and frequently lethal condition of organ dysfunction and immune dysregulation due to infection. The causes of its heterogeneity, including the contribution of the pathogen, remain unknown. Using cecal slurry, a widely used murine model of intraperitoneal polymicrobial sepsis, as well as 16S ribosomal RNA sequencing and measurement of immune markers, we performed a series of translational analyses to determine whether microbial variation in cecal slurry composition (representing intra-abdominal pathogens) mediated variation in septic response. We found wide variation in cecal slurry community composition that changed markedly over the 24-h course of infection. This variation in cecal slurry bacteria led to large variation in physiologic and inflammatory responses. Severity of inflammatory response was positively correlated with intraperitoneal enrichment with Enterobacteriaceae. Likewise, in a human cohort of patients with intra-abdominal abscesses, Enterobacteriaceae was also associated with increased inflammatory markers. Taken together, these data demonstrate that intra-abdominal Enterobacteriaceae drives inflammation in sepsis both in animal models and human subjects. More broadly, our results demonstrate that pathogen identity is a major driver of the host response in polymicrobial sepsis and should not be overlooked as a major source of phenotypic heterogeneity.

This paper presents developments in stationary phase coatings for microelectromechanical system gas chromatography (MEMS GC). Specifically, we present the coating of MEMS GC separation columns with a chiral stationary phase for the separation of amino acid enantiomers. Three commercial columns coated with chiral stationary phases from Restek were tested: Rt-βDEXm, Rt-βDEXsm, and Rt-βDEXsa. Four amino acid enantiomers ( d - and l -) were tested with the 3 commercial columns: alanine (Ala), valine (Val), leucine (Leu), and aspartic acid (Asp). The Rt-βDEXsm column provided the best experimental performance with separation of d - and l -Ala and partial separation of d - and l -Asp. The resolution, R s , values were 4.65 for the Ala enantiomers and 0.98 for the Asp enantiomers, respectively. The Rt-βDEXsm chiral stationary phase was dynamically coated on three 10-m-long microcolumns connected in series to investigate amino acid enantiomer separation. Successful separation of d - and l -Ala and partial separation of d - and l -Asp were observed with the microcolumns. The R s values from the chiral-stationary-phase-coated microcolumns were 1.21 and 0.553 for the Ala and Asp enantiomers, respectively. The chromatographically separated amino acid enantiomers were detected by the MAss Spectrometer for Planetary EXploration (MASPEX), a spaceflight mass spectrometer. Future work is required for improving the MEMS GC separation column performance consisting of testing static versus dynamic coating methods and more rigorous investigation of the stationary phase coating thickness. A discussion is provided on future work for the development of an MEMS GC suite targeting broad analyte selectivity for future space science missions.

Nanoplasmonic biosensors are highly advantageous for their label-free, robust, rapid, cost-effective, and easy-to-integrate features, making them capable of real-time detection of surface-bound analyte biomolecules. This is accomplished through a shift in photon absorbing and scattering behaviors of localized surface plasmons, which are collective oscillations of conduction-band electrons highly localized on the surfaces of metallic nanostructures. These properties make nanoplasmonic biosensors promising candidates for point-of-care testing (POCT) of diseases. However, these sensors often fall short of simultaneously achieving the speed, sensitivity, and system miniaturization required for critical care medicine. In the intensive care unit (ICU), clinicians need to quickly diagnose and intervene in life-threatening illnesses. To address this issue, the authors of this “perspective” paper presents recent advancements in their integrated nanoplasmonic biosensor technologies. Their research shows that assays integrating nanoplasmonic materials with two-dimensional (2D) nanoscale multilayer transition metal dichalcogenide (TMDC) photoconductive channels offer promising POC platforms with rapid, sensitive, selective, user-friendly on-chip biosensing capabilities.

The search for reliable protein biomarker candidates is critical for early disease detection and treatment. However, current immunoassay technologies are failing to meet increasing demands for sensitivity and multiplexing. Here, the authors have created a highly sensitive protein microarray using the principle of single-molecule counting for signal amplification, capable of simultaneously detecting a panel of cancer biomarkers at sub-pg/mL levels. To enable this amplification strategy, the authors introduce a novel method of protein patterning using photolithography to subdivide addressable arrays of capture antibody spots into hundreds of thousands of individual microwells. This allows for the total sensor area to be miniaturized, increasing the total possible multiplex capacity. With the immunoassay realized on a standard 75×25 mm form factor glass substrate, sample volume consumption is minimized to < 10 μL, making the technology highly efficient and cost-effective. Additionally, the authors demonstrate the power of their technology by measuring six secretory factors related to glioma tumor progression in a cohort of mice. This highly sensitive, sample-sparing multiplex immunoassay paves the way for researchers to track changes in protein profiles over time, leading to earlier disease detection and discovery of more effective treatment using animal models.