Pericytes Enrich the Basement Membrane and Reduce Neutrophil Transmigration in an In Vitro Model of Peripheral Inflammation at the Blood-Brain Barrier.

Sepsis is the most lethal and expensive condition treated in intensive care units. Sepsis survivors frequently suffer long-term cognitive impairment, which has been linked to the breakdown of the blood-brain barrier (BBB) during a sepsis-associated "cytokine storm". Because animal models poorly recapitulate sepsis pathophysiology, human models are needed to understand sepsis-associated brain injury and to develop novel therapeutic strategies.

Modelling a Human Blood-Brain Barrier Co-Culture Using an Ultrathin Silicon Nitride Membrane-Based Microfluidic Device.

Understanding the vesicular trafficking of receptors and receptor ligands in the brain capillary endothelium is essential for the development of the next generations of biologics targeting neurodegenerative diseases. Such complex biological questions are often approached by in vitro models in combination with various techniques. Here, we present the development of a stem cell-based human in vitro blood-brain barrier model composed of induced brain microvascular endothelial cells (iBMECs) on the modular µSiM (a microdevice featuring a silicon nitride membrane) platform.

Comparison of Toxicities among Different Bumped Kinase Inhibitor Analogs for Treatment of Cryptosporidiosis.

Recent advances on the development of bumped kinase inhibitors for treatment of cryptosporidiosis have focused on the 5-aminopyrazole-4-carboxamide scaffold, due to analogs that have less hERG inhibition, superior efficacy, and strong safety profiles. Three compounds, BKI-1770, -1841, and -1708, showed strong efficacy in C. parvum infected mice.

A tissue chip with integrated digital immunosensors: In situ brain endothelial barrier cytokine secretion monitoring.

Organ-on-a-chip platforms have potential to offer more cost-effective, ethical, and human-resembling models than animal models for disease study and drug discovery. Particularly, the Blood-Brain-Barrier-on-a-chip (BBB-oC) has emerged as a promising tool to investigate several neurological disorders since it promises to provide a model of the multifunctional tissue working as an important node to control pathogen entry, drug delivery and neuroinflammation. A comprehensive understanding of the multiple physiological functions of the tissue model requires biosensors detecting several tissue-secreted substances in a BBB-oC system.

Sourcing cells for models of human vascular barriers of inflammation.

The vascular system plays a critical role in the progression and resolution of inflammation. The contributions of the vascular endothelium to these processes, however, vary with tissue and disease state. Recently, tissue chip models have emerged as promising tools to understand human disease and for the development of personalized medicine approaches.

The Modular µSiM Reconfigured: Integration of Microfluidic Capabilities to Study In Vitro Barrier Tissue Models under Flow.

Microfluidic tissue barrier models have emerged to address the lack of physiological fluid flow in conventional "open-well" Transwell-like devices. However, microfluidic techniques have not achieved widespread usage in bioscience laboratories because they are not fully compatible with traditional experimental protocols. To advance barrier tissue research, there is a need for a platform that combines the key advantages of both conventional open-well and microfluidic systems.

The Modular µSiM: A Mass Produced, Rapidly Assembled, and Reconfigurable Platform for the Study of Barrier Tissue Models In Vitro.

Advanced in vitro tissue chip models can reduce and replace animal experimentation and may eventually support "on-chip" clinical trials. To realize this potential, however, tissue chip platforms must be both mass-produced and reconfigurable to allow for customized design. To address these unmet needs, an extension of the µSiM (microdevice featuring a silicon-nitride membrane) platform is introduced.

Molecular mechanisms underlying the heterogeneous barrier responses of two primary endothelial cell types to sphingosine-1-phosphate.

Sphingosine-1-phosphate (S1P) signals to enhance or destabilize the vascular endothelial barrier depending on the receptor engaged. Here, we investigated the differential barrier effects of S1P on two influential primary endothelial cell (EC) types, human umbilical vein endothelial cells (HUVECs) and human pulmonary microvascular endothelial cells (HPMECs). S1PR1 (barrier protective) and S1PR3 (barrier disruptive) surface and gene expression were quantified by flow cytometry and immunofluorescence, and RT-qPCR, respectively.

Rapid and specific detection of intact viral particles using functionalized microslit silicon membranes as a fouling-based sensor.

The COVID-19 pandemic demonstrated the public health benefits of reliable and accessible point-of-care (POC) diagnostic tests for viral infections. Despite the rapid development of gold-standard reverse transcription polymerase chain reaction (RT-PCR) assays for SARS-CoV-2 only weeks into the pandemic, global demand created logistical challenges that delayed access to testing for months and helped fuel the spread of COVID-19. Additionally, the extreme sensitivity of RT-PCR had a costly downside as the tests could not differentiate between patients with active infection and those who were no longer infectious but still shedding viral genomes.

Studies of Transendothelial Migration for Biological and Drug Discovery.

Inflammatory diseases and cancer metastases lack concrete pharmaceuticals for their effective treatment despite great strides in advancing our understanding of disease progression. One feature of these disease pathogeneses that remains to be fully explored, both biologically and pharmaceutically, is the passage of cancer and immune cells from the blood to the underlying tissue in the process of extravasation. Regardless of migratory cell type, all steps in extravasation involve molecular interactions that serve as a rich landscape of targets for pharmaceutical inhibition or promotion.

Bumped Kinase Inhibitors as therapy for apicomplexan parasitic diseases: lessons learned.

Bumped Kinase Inhibitors, targeting Calcium-dependent Protein Kinase 1 in apicomplexan parasites with a glycine gatekeeper, are promising new therapeutics for apicomplexan diseases. Here we will review advances, as well as challenges and lessons learned regarding efficacy, safety, and pharmacology that have shaped our selection of pre-clinical candidates.

Microvascular Mimetics for the Study of Leukocyte-Endothelial Interactions.

Introduction: The pathophysiological increase in microvascular permeability plays a well-known role in the onset and progression of diseases like sepsis and atherosclerosis. However, how interactions between neutrophils and the endothelium alter vessel permeability is often debated.

Methods: In this study, we introduce a microfluidic, silicon-membrane enabled vascular mimetic (μSiM-MVM) for investigating the role of neutrophils in inflammation-associated microvascular permeability.

Author Correction: Evaluation of in vitro and in vivo antibiotic efficacy against a novel bioluminescent Shigella flexneri.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Evaluation of in vitro and in vivo antibiotic efficacy against a novel bioluminescent Shigella flexneri.

Shigella spp., the bacteria responsible for shigellosis, are one of the leading causes of diarrheal morbidity and mortality amongst children. There is a pressing need for the development of novel therapeutics, as resistance of Shigella to many currently used antibiotics is rapidly emerging.

P-Glycoprotein-Mediated Efflux Reduces the In Vivo Efficacy of a Therapeutic Targeting the Gastrointestinal Parasite Cryptosporidium.

Recent studies have illustrated the burden Cryptosporidium infection places on the lives of malnourished children and immunocompromised individuals. Treatment options remain limited, and efforts to develop a new therapeutic are currently underway. However, there are unresolved questions about the ideal pharmacokinetic characteristics of new anti-Cryptosporidium therapeutics.

Development of 5-Aminopyrazole-4-carboxamide-based Bumped-Kinase Inhibitors for Cryptosporidiosis Therapy.

Cryptosporidium is a leading cause of pediatric diarrhea worldwide. Currently, there is neither a vaccine nor a consistently effective drug available for this disease. Selective 5-aminopyrazole-4-carboxamide-based bumped-kinase inhibitors (BKIs) are effective in both in vitro and in vivo models of Cryptosporidium parvum.

Pharmacokinetics and In Vivo Efficacy of Pyrazolopyrimidine, Pyrrolopyrimidine, and 5-Aminopyrazole-4-Carboxamide Bumped Kinase Inhibitors against Toxoplasmosis.

Bumped kinase inhibitors (BKIs) have been shown to be potent inhibitors of Toxoplasma gondii calcium-dependent protein kinase 1. Pyrazolopyrimidine and 5-aminopyrazole-4-carboxamide scaffold-based BKIs are effective in acute and chronic experimental models of toxoplasmosis. Through further exploration of these 2 scaffolds and a new pyrrolopyrimidine scaffold, additional compounds have been identified that are extremely effective against acute experimental toxoplasmosis.

Screening of the Pathogen Box for inhibitors with dual efficacy against Giardia lamblia and Cryptosporidium parvum.

There is need for a more efficient cell-based assay amenable to high-throughput drug screening against Giardia lamblia. Here, we report the development of a screening method utilizing G. lamblia engineered to express red-shifted firefly luciferase.

7 H-Pyrrolo[2,3- d]pyrimidin-4-amine-Based Inhibitors of Calcium-Dependent Protein Kinase 1 Have Distinct Inhibitory and Oral Pharmacokinetic Characteristics Compared with 1 H-Pyrazolo[3,4- d]pyrimidin-4-amine-Based Inhibitors.

Selective inhibitors of Cryptosporidium calcium-dependent protein kinase 1 ( CpCDPK1) based on the 1 H-pyrazolo[3,4- d]pyrimidin-4-amine (pyrazolopyrimidine, PP) scaffold are effective in both in vitro and in vivo models of cryptosporidiosis. However, the search for distinct safety and pharmacokinetic (PK) properties has motivated our exploration of alternative scaffolds. Here, we describe a series of 7 H-pyrrolo[2,3- d]pyrimidin-4-amine (pyrrolopyrimidine, PrP)-based analogs of PP CpCDPK1 inhibitors.

Advances in bumped kinase inhibitors for human and animal therapy for cryptosporidiosis.

Improvements have been made to the safety and efficacy of bumped kinase inhibitors, and they are advancing toward human and animal use for treatment of cryptosporidiosis. As the understanding of bumped kinase inhibitor pharmacodynamics for cryptosporidiosis therapy has increased, it has become clear that better compounds for efficacy do not necessarily require substantial systemic exposure. We now have a bumped kinase inhibitor with reduced systemic exposure, acceptable safety parameters, and efficacy in both the mouse and newborn calf models of cryptosporidiosis.

Necessity of Bumped Kinase Inhibitor Gastrointestinal Exposure in Treating Cryptosporidium Infection.

There is a substantial need for novel therapeutics to combat the widespread impact caused by Crytosporidium infection. However, there is a lack of knowledge as to which drug pharmacokinetic (PK) characteristics are key to generate an in vivo response, specifically whether systemic drug exposure is crucial for in vivo efficacy. To identify which PK properties are correlated with in vivo efficacy, we generated physiologically based PK models to simulate systemic and gastrointestinal drug concentrations for a series of bumped kinase inhibitors (BKIs) that have nearly identical in vitro potency against Cryptosporidium but display divergent PK properties.

5-Aminopyrazole-4-Carboxamide-Based Compounds Prevent the Growth of Cryptosporidium parvum.

calcium-dependent protein kinase 1 (CDPK1) is a promising target for drug development against cryptosporidiosis. We report a series of low-nanomolar CDPK1 5-aminopyrazole-4-carboxamide (AC) scaffold inhibitors that also potently inhibit growth Correlation between anti-CDPK1 and growth inhibition, as previously reported for pyrazolopyrimidines, was not apparent. Nonetheless, lead AC compounds exhibited a substantial reduction of parasite burden in the neonatal mouse cryptosporidiosis model when dosed at 25 mg/kg.