Multidrug Combinations against SARS-CoV-2 Using GS-441524 or Ivermectin with Molnupiravir and/or Nirmatrelvir in Reconstituted Human Nasal Airway Epithelia.

The emergence, global spread, and persistence of SARS-CoV-2 resulted in an unprecedented need for effective antiviral drugs. Throughout the pandemic, various drug development and treatment strategies were adopted, including repurposing of antivirals designed for other viruses along with a multitude of other drugs with varying mechanisms of action (MoAs). Furthermore, multidrug treatment against COVID-19 is an ongoing topic and merits further investigation.

The triple combination of Remdesivir (GS-441524), Molnupiravir and Ribavirin is highly efficient in inhibiting coronavirus replication in human nasal airway epithelial cell cultures and in a hamster infection model.

The use of fixed dose-combinations of antivirals with different mechanisms of action has proven key in the successful treatment of infections with HIV and HCV. For the treatment of infections with SARS-CoV-2 and possible future epi-/pandemic coronaviruses, it will be important to explore the efficacy of combinations of different drugs, in particular to avoid resistance development, such as in patients with immunodeficiencies. This work explores the effect of a combination of 3 broad-spectrum antiviral nucleosides on the replication of coronaviruses.

Establishment of a human nasal epithelium model of histamine-induced inflammation to assess the activity of fexofenadine as an inverse agonist and its link to clinical benefit.

Background: Fexofenadine (FEX) is an antihistamine that acts as an inverse agonist against histamine (HIS) receptor 1 (H1R), which mediates the allergic reaction. Inverse agonists may be more potent than neutral antagonists, as they bind the same receptor as the agonist (HIS) but stabilize the inactive form and induce an opposite pharmacological response, suppressing the basal activity of H1R and preventing HIS from binding. This study aims to establish and validate a model of HIS-induced inflammation based on fully reconstituted human nasal epithelial tissue to assess the activity of FEX as an inverse agonist in this model and explore its link to clinical benefit.

The triple combination of Remdesivir (GS-441524), Molnupiravir and Ribavirin is highly efficient in inhibiting coronavirus replication in human nasal airway epithelial cell cultures and in a hamster infection model.

The use of fixed dose-combinations of antivirals with different mechanisms of action has proven a key in the successful treatment of infections with HIV and HCV. For the treatment of infections with SARS-CoV-2 and possible future epi-/pandemic coronaviruses, it will be important to explore the efficacy of combinations of different drugs, in particular to avoid resistance development, such as in patients with immunodeficiencies. As a first effort, we studied the antiviral potency of combinations of antivirals.

Altered cell function and increased replication of rhinoviruses and EV-D68 in airway epithelia of asthma patients.

Introduction: Rhinovirus (RV) infections constitute one of the main triggers of asthma exacerbations and an important burden in pediatric yard. However, the mechanisms underlying this association remain poorly understood.

Methods: In the present study, we compared infections of reconstituted airway epithelia originating from asthmatic versus healthy donors with representative strains of RV-A major group and minor groups, RV-C, RV-B, and the respiratory enterovirus EV-D68.

Why people die of active tuberculosis in the era of effective chemotherapy in Southern Ethiopia: A qualitative study.

Background: High TB mortality is increasingly understood as an indicator of different problems in the health system and community. Limited awareness of TB in the community, restricted accessibility and/or quality of health services can hamper survival. Exploration and analysis of death among TB patients can lead to a clearer and specific understanding of why the deaths happened and where interventions are likely to make a difference in a specific context.

Molnupiravir combined with different repurposed drugs further inhibits SARS-CoV-2 infection in human nasal epithelium in vitro.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a worldwide pandemic with unprecedented economic and societal impact. Currently, several vaccines are available and multitudes of antiviral treatments have been proposed and tested. Although many of the vaccines show clinical efficacy, they are not equally accessible worldwide.

Chronic Obstructive Pulmonary Disease and Associated Factors in Arba Minch Health and Demographic Surveillance Site, 2020.

Introduction: Chronic obstructive pulmonary disease (COPD) is a worldwide public health problem. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) defines COPD as a common, preventable and treatable disease characterized by progressive airflow limitation. Nowadays, COPD has become the third leading cause of death and fourth cause of mortality in the world.

Antiviral drug screening by assessing epithelial functions and innate immune responses in human 3D airway epithelium model.

Respiratory viral infections cause mild to severe diseases, such as common cold, bronchiolitis and pneumonia and are associated with substantial burden for society. To test new molecules for shortening, alleviating the diseases or to develop new therapies, relevant human in vitro models are mandatory. MucilAir™, a human standardized air-liquid interface 3D airway epithelial culture holds in vitro specific mechanisms to counter invaders comparable to the in vivo situation, such as mucus production, mucociliary clearance, and secretion of defensive molecules.

Establishment and characterization of an in vitro human small airway model (SmallAir™).

We report here the establishment and characterization of an in vitro human small airway model (SmallAir™). The epithelial cells were isolated from the distal lungs by enzymatic digestion. After amplification, the cells were seeded on the microporous membrane of Transwell inserts.

Establishment of a tumour-stroma airway model (OncoCilAir) to accelerate the development of human therapies against lung cancer.

This paper highlights the work for which OncoTheis, a Swiss biotechnology company, engaged in the development of innovative bioengineered tissues and organoids for cancer research, was co-awarded the 2015 Lush Science Prize. Noting that the use of animal models failed to lead to the design of effective treatments for cancer, OncoTheis has opted to develop in vitro models based exclusively on human cells. The company currently focuses on lung cancer, which is the leading cause of cancer-related deaths worldwide, with more than one million deaths per year.

Antitumour efficacy of the selumetinib and trametinib MEK inhibitors in a combined human airway-tumour-stroma lung cancer model.

With more than 1 million deaths worldwide every year, lung cancer remains an area of unmet need. Accessible human in vitro 3D tissue models are required to improve preclinical predictivity. OncoCilAir™ is a new in vitro model of Non Small Cell Lung Cancer which combines a reconstituted human airway epithelium, human lung fibroblasts and lung adenocarcinoma cell lines.

Reversal of activity-mediated spine dynamics and learning impairment in a mouse model of Fragile X syndrome.

Fragile X syndrome (FXS) is characterized by intellectual disability and autistic traits, and results from the silencing of the FMR1 gene coding for a protein implicated in the regulation of protein synthesis at synapses. The lack of functional Fragile X mental retardation protein has been proposed to result in an excessive signaling of synaptic metabotropic glutamate receptors, leading to alterations of synapse maturation and plasticity. It remains, however, unclear how mechanisms of activity-dependent spine dynamics are affected in Fmr knockout (Fmr1-KO) mice and whether they can be reversed.

Synaptotagmin 1 is required for vesicular Ca²⁺/H⁺-antiport activity.

A low-affinity Ca²⁺/H⁺-antiport was described in the membrane of mammalian brain synaptic vesicles. Electrophysiological studies showed that this antiport contributes to the extreme brevity of excitation-release coupling in rapid synapses. Synaptotagmin-1, a vesicular protein interacting with membranes upon low-affinity Ca²⁺-binding, plays a major role in excitation-release coupling, by synchronizing calcium entry with fast neurotransmitter release.

Alteration of synaptic network dynamics by the intellectual disability protein PAK3.

Several gene mutations linked to intellectual disability in humans code for synaptic molecules implicated in small GTPase signaling. This is the case of the Rac/Cdc42 effector p21-activated kinase 3 (PAK3). The mechanisms responsible for the intellectual defects and the consequences of the mutation on the development and wiring of brain networks remain unknown.

Signaling mechanisms regulating synapse formation and function in mental retardation.

Major progress has been carried out in the last two decades in the identification of genetic alterations associated with mental retardation and autism spectrum disorders. In many instances these defects concern genes coding for synaptic proteins or proteins involved in regulation of synaptic properties. Analyses of the underlying mechanisms using gain and loss of function approaches have revealed alterations of spine morphology, density or plasticity, raising the possibility that these disorders result from synaptopathies.

PSD-95 promotes synaptogenesis and multiinnervated spine formation through nitric oxide signaling.

Postsynaptic density 95 (PSD-95) is an important regulator of synaptic structure and plasticity. However, its contribution to synapse formation and organization remains unclear. Using a combined electron microscopic, genetic, and pharmacological approach, we uncover a new mechanism through which PSD-95 regulates synaptogenesis.

Distinct, but compensatory roles of PAK1 and PAK3 in spine morphogenesis.

PAK1 and PAK3 belong to a family of protein kinases that are effectors of small Rho GTPases. In humans, mutations of PAK3 have been associated with mental retardation and result in in vitro studies in defects of spine morphogenesis. The functional specificities of PAK1 and PAK3 remain, however, unclear.

SLC25A12 expression is associated with neurite outgrowth and is upregulated in the prefrontal cortex of autistic subjects.

Autism is a neurodevelopmental disorder with a strong genetic component, probably involving several genes. Genome screens have provided evidence of linkage to chromosome 2q31-q33, which includes the SLC25A12 gene. Association between autism and single-nucleotide polymorphisms in SLC25A12 has been reported in various studies.

The p21-activated kinase 3 implicated in mental retardation regulates spine morphogenesis through a Cdc42-dependent pathway.

The p21-activated kinase 3 (PAK3) is one of the recently identified genes for which mutations lead to nonsyndromic mental retardation. PAK3 is implicated in dendritic spine morphogenesis and is a key regulator of synaptic functions. However, the underlying roles of PAK3 in these processes remain poorly understood.

Sequential implication of the mental retardation proteins ARHGEF6 and PAK3 in spine morphogenesis.

The biological mechanisms underlying the mental retardation associated with mutation of the ARHGEF6 gene, a Rac1/Cdc42 exchange factor, are still unknown, although defects in the plasticity of synaptic networks have been postulated. We have cloned the rat ARHGEF6 gene and investigated, using a transfection approach, its involvement in spine morphogenesis and its relationship to p21-activated kinase 3 (PAK3). We found that expression of tagged ARHGEF6 in hippocampal slice cultures shows a punctate staining in dendritic spines that colocalizes with PSD95.

Central nervous system functions of PAK protein family: from spine morphogenesis to mental retardation.

Several of the genes currently known to be associated, when mutated, with mental retardation, code for molecules directly involved in Rho guanosine triphosphatase (GTPase) signaling. These include PAK3, a member of the PAK protein kinase family, which are important effectors of small GTPases. In many systems, PAK kinases play crucial roles regulating complex mechanisms such as cell migration, differentiation, or survival.

Application of photoconversion technique for correlated confocal and ultrastructural studies in organotypic slice cultures.

Photoconversion of fluorescent staining into stable diaminobenzidine (DAB) precipitate is widely used for neuroanatomical and developmental studies. An important advantage of the approach is to make correlations between light and electron microscopy analyses possible, the DAB reaction product formed during photoconversion being electron dense. By combining a photoconversion approach with biolistic transfection of neurons in organotypic hippocampal slice cultures, we describe here a methodology that allowed us to study at the electron microscopy level the fine details of cells expressing specific genes of interest.

The endosomal protein NEEP21 regulates AMPA receptor-mediated synaptic transmission and plasticity in the hippocampus.

The neuron-enriched endosomal protein 21 (NEEP21) has recently been implicated in the regulation of AMPA receptor (AMPAR) trafficking and proposed to participate in the control of synaptic strength. We tested here this possibility at CA3-CA1 synapses in hippocampal slice cultures using antisense-mediated down-regulation of NEEP21 expression or transfection of a fragment of the cytosolic domain of NEEP21. We found that NEEP21 suppression or expression of the dominant-negative fragment reduced spontaneous and evoked AMPAR-mediated synaptic currents without affecting presynaptic properties.

Molecular cloning and expression pattern of the Fkbp25 gene during cerebral cortical neurogenesis.

Neocortical neurons are generated predominantly from the cells that proliferate in the ventricular zone of the telencephalon. In order to understand the nature of these expanding cortical neuronal progenitor cells, we selected by differential display some transcripts that were enriched in the telencephalon as compared to the more caudal regions (diencephalon/mesencephalon). This systematic screening revealed one of the differentially expressed transcripts, namely the Fkbp25 mRNA that encodes a member of the FK506 binding proteins (FKBPs).