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The blood-brain barrier (BBB) restricts paracellular and transcellular diffusion of compounds and is part of a dynamic multicellular structure known as the ‘neurovascular unit’ (NVU), which strictly regulates the brain homeostasis and microenvironment. Several neuropathological conditions, (e.g., Parkinson’s disease and Alzheimer’s disease) are associated with BBB impairment yet the exact underlying pathophysiological mechanisms remain unclear. 90% of drugs that pass animal testing fail human clinical trials, in part due to inter-species discrepancies. Thus, in vitro human-based models of the NVU are essential to better understand BBB mechanisms; connecting its dysfunction to neuro-pathological conditions for more effective and improved therapeutic treatments. Herein, we developed a biomimetic tri-culture NVU in vitro model consisting of 3 human-derived cell lines: human cerebral micro-vascular endothelial cells (hCMEC/D3), human 1321N1 (astrocyte) cells, and human SH-SY5Y neuroblastoma cells. The cells were grown in Transwell hanging inserts in a variety of configurations and the optimal setup was found to be the comprehensive tri-culture model, where endothelial cells express typical markers of the BBB and contribute to enhancing neural cell viability and neurite outgrowth. The tri-culture configuration was found to exhibit the highest transendothelial electrical resistance (TEER), suggesting that the cross-talk between astrocytes and neurons provides an important contribution to barrier integrity. Lastly, the model was validated upon exposure to several soluble factors (e.g., LPS, sodium butyrate and retinoic acid) known to affect BBB permeability and integrity. This in vitro biological model can be considered as a highly biomimetic recapitulation of the human NVU aiming to unravel brain pathophysiology mechanisms as well as improve testing and delivery of therapeutics.

The role of the gut microbiome in various aspects of health and disease is now a well‐established concept in modern biomedicine. Numerous studies have revealed links between host health and microbial activity, spanning from digestion and metabolism to autoimmune disorders, stress and neuroinflammation. However, the exact mechanisms underlying this complex cross‐talk still remain a mystery. Conventionally, studies examining host‐microbiome interactions rely on animal models, but translation of such findings into human systems is challenging. Bioengineered models represent a highly promisingapproach for tackling such challenges. Here, a bioelectronic platform, the e‐transmembrane, is used to establish a 3D model of human intestine, to study the effects of microbiota on gut barrier integrity. More specifically, how postbiotics and live bacteria impact the morphology and function of the intestinal barrier is evaluated. e‐Transmembrane devices provide a means for in‐line and label‐free continuous monitoring of host‐microbe cross‐talk using electrochemical impedance spectroscopy, revealing distinct patterns that emerge over 24 hours. Microscopy and quantification of molecular biomarkers further validate the differential effects of each bacterial intervention on the host tissue. In addition, a framework to better study and screen drug candidates and potential therapeutic/dietary interventions, such as postbiotics and probiotics, in more physiologically relevant human models is provided. A novel 3D bioelectronic platform, “e‐Transmembrane”, provides a unique biomimetic niche for the development and dynamic monitoring of an advanced human stratified intestinal model. Exposure of this bioengineered tissue to postbiotic cohorts or live bacteria showcases the unique capabilities of the platform to model gut–microbiota interactions, offering a new and sophisticated way to study such complex systems in vitro.

Drug studies targeting neuronal ion channels are crucial to understand neuronal function and develop therapies for neurological diseases. The traditional method to study neuronal ion‐channel activities heavily relies on the whole‐cell patch clamp as the industry standard. However, this technique is both technically challenging and labour‐intensive, while involving the complexity of keeping cells alive with low throughput. Therefore, the shortcomings are limiting the efficiency of ion‐channel‐related neuroscience research and drug testing. Here, this work reports a new system of integrating neuron membranes with organic microelectrode arrays (OMEAs) for ion‐channel‐related drug studies. This work demonstrates that the supported lipid bilayers (SLBs) derived from both neuron‐like (neuroblastoma) cells and primary neurons are integrated with OMEAs for the first time. The increased expression of voltage‐gated calcium (CaV) ion channels on differentiated SH‐SY5Y SLBs  compared to non‐differentiated ones is sensed electrically. Also, dose‐response of the CaV ion‐channel blocking effect on primary cortical neuronal SLBs from rats is monitored. The dose range causing ion channel blocking is comparable to literature. This system overcomes the major challenges from traditional methods (e.g., patch clamp) and showcases an easy‐to‐test, rapid, ultra‐sensitive, cell‐free, and high‐throughput platform to monitor dose‐dependent ion‐channel blocking effects on native neuronal membranes. Primary neuron membranes can be isolated and integrated with microelectrode arrays. This is a study using electrochemical impedance spectroscopy for monitoring the neuronal membrane quality and detecting ion channel blockage on the neuron membranes, which could be a novel technique for drug screening and neuroscience research.

Neuronal‐Membrane‐on‐Chip The cover highlights a novel platform of interfacing cell membranes derived from primary neurons with organic microelectrode arrays for monitoring ion channel activities at natively‐expressed levels. In article number 2304301, Róisín M. Owens and colleagues showcase the ease of testing, rapidity, ultra‐sensitivity, and high‐throughput capabilities. This work introduces a new class of neuroscience tools promising to unveil insights into drug and ion‐channels interactions. Art by the team of Inmywork Studio.

Three-dimensional in vitro stem cell models has enabled a fundamental understanding of cues that direct stem cell fate and be used to develop novel stem cell treatments. While sophisticated 3D tissues can be generated, technology that can accurately monitor these complex models in a high-throughput and non-invasive manner is not well adapted. Here we show the development of 3D bioelectronic devices based on the electroactive polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) - PEDOT:PSS and their use for non-invasive, electrical monitoring of stem cell growth. We show that the electrical, mechanical and wetting properties as well as the pore size/architecture of 3D PEDOT:PSS scaffolds can be fine-tuned simply by changing the processing crosslinker additive. We present a comprehensive characterization of both 2D PEDOT:PSS thin films of controlled thicknesses, and 3D porous PEDOT:PSS structures made by the freeze-drying technique. By slicing the bulky scaffolds we show that homogeneous, porous 250 um thick PEDOT:PSS slices are produced, generating biocompatible 3D constructs able to support stem cell cultures. These multifunctional membranes are attached on Indium-Tin oxide substrates (ITO) with the help of an adhesion layer that is used to minimize the interface charge resistance. The optimum electrical contact result in 3D devices with a characteristic and reproducible, frequency dependent impedance response. This response changes drastically when human adipose derived stem cells grow within the porous PEDOT:PSS network as revealed by fluorescence microscopy. The increase of these stem cell population within the PEDOT:PSS porous network impedes the charge flow at the interface between PEDOT:PSS and ITO, enabling the interface resistance to be extracted by equivalent circuit modelling, used here as a figure of merit to monitor the proliferation of stem cells. The strategy of controlling important properties of 3D PEDOT:PSS structures simply by altering processing parameters can be applied for development of a number of stem cell in vitro models. We believe the results presented here will advance 3D bioelectronic technology for both fundamental understanding of in vitro stem cell cultures as well as the development of personalized therapies.

Expression of stromal antigen 2 (STAG2), a member of the cohesin complex, is associated with aggressive tumor characteristics and worse clinical outcomes in muscle invasive bladder cancer (MIBC) patients. The mechanism by which STAG2 acts in a pro-oncogenic manner in bladder cancer remains unknown. Due to this elusive role of STAG2, targetable vulnerabilities based on STAG2 expression have not yet been identified. In the current study, we sought to uncover therapeutic vulnerabilities of muscle invasive bladder cancer cells based on the expression of STAG2. Using CRISPR-Cas9, we generated isogenic STAG2 wild-type (WT) and knock out (KO) cell lines and treated each cell line with a panel of 312 anti-cancer compounds. We identified 100 total drug hits and found that STAG2 KO sensitized cells to treatment with PLK1 inhibitor rigosertib, whereas STAG2 KO protected cells from treatment with MEK inhibitor TAK-733 and PI3K inhibitor PI-103. After querying drug sensitivity data of over 4500 drugs in 24 bladder cancer cell lines from the DepMap database, we found that cells with less STAG2 mRNA expression are more sensitive to ATR and CHK inhibition. In dose-response studies, STAG2 KO cells are more sensitive to the ATR inhibitor berzosertib, whereas STAG2 WT cells are more sensitive to PI3K inhibitor PI-103. These results, in combination with RNA-seq analysis of STAG2-regulated genes, suggest a novel role of STAG2 in regulating PI3K signaling in bladder cancer cells. Finally, synergy experiments revealed that berzosertib exhibits significant synergistic cytotoxicity in combination with cisplatin against MIBC cells. Altogether, our study presents evidence that berzosertib, PI-103, and the combination of berzosertib with cisplatin may be novel opportunities to investigate as precision medicine approaches for MIBC patients based on STAG2 tumor expression.

AbstractObjectiveTo compare the effectiveness of a primary covid-19 vaccine series plus booster doses with a primary series alone for the prevention of hospital admission with omicron related covid-19 in the United States.DesignMulticenter observational case-control study with a test negative design.SettingHospitals in 18 US states.Participants4760 adults admitted to one of 21 hospitals with acute respiratory symptoms between 26 December 2021 and 30 June 2022, a period when the omicron variant was dominant. Participants included 2385 (50.1%) patients with laboratory confirmed covid-19 (cases) and 2375 (49.9%) patients who tested negative for SARS-CoV-2 (controls).Main outcome measuresThe main outcome was vaccine effectiveness against hospital admission with covid-19 for a primary series plus booster doses and a primary series alone by comparing the odds of being vaccinated with each of these regimens versus being unvaccinated among cases versus controls. Vaccine effectiveness analyses were stratified by immunosuppression status (immunocompetent, immunocompromised). The primary analysis evaluated all covid-19 vaccine types combined, and secondary analyses evaluated specific vaccine products.ResultsOverall, median age of participants was 64 years (interquartile range 52-75 years), 994 (20.8%) were immunocompromised, 85 (1.8%) were vaccinated with a primary series plus two boosters, 1367 (28.7%) with a primary series plus one booster, and 1875 (39.3%) with a primary series alone, and 1433 (30.1%) were unvaccinated. Among immunocompetent participants, vaccine effectiveness for prevention of hospital admission with omicron related covid-19 for a primary series plus two boosters was 63% (95% confidence interval 37% to 78%), a primary series plus one booster was 65% (58% to 71%), and for a primary series alone was 37% (25% to 47%) (P<0.001 for the pooled boosted regimens compared with a primary series alone). Vaccine effectiveness was higher for a boosted regimen than for a primary series alone for both mRNA vaccines (BNT162b2 (Pfizer-BioNTech): 73% (44% to 87%) for primary series plus two boosters, 64% (55% to 72%) for primary series plus one booster, and 36% (21% to 48%) for primary series alone (P<0.001); mRNA-1273 (Moderna): 68% (17% to 88%) for primary series plus two boosters, 65% (55% to 73%) for primary series plus one booster, and 41% (25% to 54%) for primary series alone (P=0.001)). Among immunocompromised patients, vaccine effectiveness for a primary series plus one booster was 69% (31% to 86%) and for a primary series alone was 49% (30% to 63%) (P=0.04).ConclusionDuring the first six months of 2022 in the US, booster doses of a covid-19 vaccine provided additional benefit beyond a primary vaccine series alone for preventing hospital admissions with omicron related covid-19.Readers’ noteThis article is a living test negative design study that will be updated to reflect emerging evidence. Updates may occur for up to two years from the date of original publication.

Immunosuppressive myeloid cells in the tumor microenvironment play a major role in suppressing tumor immunity via the production of arginase, IL-10, and others. The objectives of this study were to determine the ability of all-trans retinoic acid (ATRA) to decrease the expression of arginase and other soluble mediators by canine monocyte-derived macrophages (MDMs) and to determine the inhibitory activity of arginase on canine T-lymphocytes. The immunomodulatory ability of ATRA (2 µM) on canine MDMs was evaluated via reverse transcription quantitative PCR (RT-qPCR), flow cytometry, arginase activity assay, and enzyme-linked immunoassay (ELISA). Arginase effects on T-lymphocyte phenotype and proliferation were then evaluated by flow cytometry. ATRA consistently decreased MDM expression of IL6, TGFB1, NOS2, ARG1, and CIITA transcripts, by approximately 2–4-fold, although this did not reach statistical significance for ARG1 or CIITA. Furthermore, arginase activity was decreased in ATRA-treated MDMs while the MDM phenotype remained unchanged. Arginase decreased the expression of granzyme B on CD8+ T-lymphocytes and inhibited CD4+ and CD8+ T-lymphocyte proliferation. These findings suggested that ATRA could inhibit canine MDM production of soluble inflammatory/immunosuppressive mediators. These data also revealed that arginase decreased canine T-lymphocyte proliferation and granzyme B expression. Further studies are needed to determine whether ATRA could reverse the immunosuppressive effects of myeloid cells on canine T-lymphocytes in vivo.

Abstract Background Coronavirus disease 2019 (COVID-19) vaccine effectiveness (VE) studies are increasingly reporting relative VE (rVE) comparing a primary series plus booster doses with a primary series only. Interpretation of rVE differs from traditional studies measuring absolute VE (aVE) of a vaccine regimen against an unvaccinated referent group. We estimated aVE and rVE against COVID-19 hospitalization in primary-series plus first-booster recipients of COVID-19 vaccines. Methods Booster-eligible immunocompetent adults hospitalized at 21 medical centers in the United States during December 25, 2021–April 4, 2022 were included. In a test-negative design, logistic regression with case status as the outcome and completion of primary vaccine series or primary series plus 1 booster dose as the predictors, adjusted for potential confounders, were used to estimate aVE and rVE. Results A total of 2060 patients were analyzed, including 1104 COVID-19 cases and 956 controls. Relative VE against COVID-19 hospitalization in boosted mRNA vaccine recipients versus primary series only was 66% (95% confidence interval [CI], 55%–74%); aVE was 81% (95% CI, 75%–86%) for boosted versus 46% (95% CI, 30%–58%) for primary. For boosted Janssen vaccine recipients versus primary series, rVE was 49% (95% CI, −9% to 76%); aVE was 62% (95% CI, 33%–79%) for boosted versus 36% (95% CI, −4% to 60%) for primary. Conclusions Vaccine booster doses increased protection against COVID-19 hospitalization compared with a primary series. Comparing rVE measures across studies can lead to flawed interpretations of the added value of a new vaccination regimen, whereas difference in aVE, when available, may be a more useful metric. Although relative vaccine effectiveness can be a useful measure to understand incremental benefit of a vaccine booster regimen compared with a primary series alone, absolute vaccine effectiveness estimates are needed to fully understand their benefit.