scholarly journals Preclinical Models of Nontuberculous Mycobacteria Infection for Early Drug Discovery and Vaccine Research

Pathogens ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 641
Author(s):  
Elisa Rampacci ◽  
Valentina Stefanetti ◽  
Fabrizio Passamonti ◽  
Marcela Henao-Tamayo

Nontuberculous mycobacteria (NTM) represent an increasingly prevalent etiology of soft tissue infections in animals and humans. NTM are widely distributed in the environment and while, for the most part, they behave as saprophytic organisms, in certain situations, they can be pathogenic, so much so that the incidence of NTM infections has surpassed that of Mycobacterium tuberculosis in developed countries. As a result, a growing body of the literature has focused attention on the critical role that drug susceptibility tests and infection models play in the design of appropriate therapeutic strategies against NTM diseases. This paper is an overview of the in vitro and in vivo models of NTM infection employed in the preclinical phase for early drug discovery and vaccine development. It summarizes alternative methods, not fully explored, for the characterization of anti-mycobacterial compounds.

Author(s):  
Loh Teng Hern Tan ◽  
Liang Ee Low ◽  
Siah Ying Tang ◽  
Wei Hsum Yap ◽  
Lay Hong Chuah ◽  
...  

Three-dimensional cell culture methods revolutionize the field of anticancer drug discovery, forming an important link-bridge between conventional in vitro and in vivo models and conferring significant clinical and biological relevant data. The current work presents an affordable yet reproducible method of generating homogenous 3D tumor spheroids. Also, a new open source software is adapted to perform an automated image analysis of 3D tumor spheroids and subsequently generate a list of morphological parameters of which could be utilized to determine the response of these spheroids toward treatments. Our data showed that this work could serve as a reliable 3D cell culture platform for preclinical cytotoxicity testing of natural products prior to the expensive and time-consuming animal models


Vaccines ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 1501
Author(s):  
Sarah Brendle ◽  
Nancy Cladel ◽  
Karla Balogh ◽  
Samina Alam ◽  
Neil Christensen ◽  
...  

Human papillomavirus (HPV) 16 capsids have been chosen as a DNA delivery vehicle in many studies. Our preliminary studies suggest that HPV58 capsids could be better vehicles than HPV16 capsids to deliver encapsidated DNA in vitro and in vivo. In the current study, we compared HPV16, HPV58, and the cottontail rabbit papillomavirus (CRPV) capsids either as L1/L2 VLPs or pseudoviruses (PSVs) to deliver externally attached GFP-expressing DNA. Both rabbit and human cells were used to test whether there was a species-specific effect. DNA delivery efficiency was determined by quantifying either GFP-expressing cell populations or mean fluorescent intensities (MFI) by flow cytometry. Interestingly, CRPV and 58-VLPs and PSVs were significantly more efficient at delivering attached DNA when compared to 16-VLPs and PSVs. A capsid/DNA ratio of 2:1 showed the highest efficiency for delivering external DNA. The PSVs with papillomavirus DNA genomes also showed higher efficiency than those with irrelevant plasmid DNA. HPV16L1/58L2 hybrid VLPs displayed increased efficiency compared to HPV58L1/16L2 VLPs, suggesting that L2 may play a critical role in the delivery of attached DNA. Additionally, we demonstrated that VLPs increased in vivo infectivity of CRPV DNA in rabbits. We conclude that choosing CRPV or 58 capsids to deliver external DNA could improve DNA uptake in in vitro and in vivo models.


2019 ◽  
Vol 10 (11) ◽  
Author(s):  
Chuangyu Wen ◽  
Huihui Wang ◽  
Xiaobin Wu ◽  
Lu He ◽  
Qian Zhou ◽  
...  

Abstract Novel drugs are urgently needed for gastric cancer (GC) treatment. The thioredoxin-thioredoxin reductase (TRX-TRXR) system has been found to play a critical role in GC tumorigenesis and progression. Thus, agents that target the TRX-TRXR system may be highly efficacious as GC treatments. In this study, we showed that chaetocin, a natural product isolated from the Chaetomium species of fungi, inhibited proliferation, induced G2/M phase arrest and caspase-dependent apoptosis in both in vitro and in vivo models (cell xenografts and patient-derived xenografts) of GC. Chaetocin inactivated TRXR-1, resulting in the accumulation of reactive oxygen species (ROS) in GC cells; overexpression of TRX-1 as well as cotreatment of GC cells with the ROS scavenger N-acetyl-L-cysteine attenuated chaetocin-induced apoptosis; chaetocin-induced apoptosis was significantly increased when GC cells were cotreated with auranofin. Moreover, chaetocin was shown to inactivate the PI3K/AKT pathway by inducing ROS generation; AKT-1 overexpression also attenuated chaetocin-induced apoptosis. Taken together, these results reveal that chaetocin induces the excessive accumulation of ROS via inhibition of TRXR-1. This is followed by PI3K/AKT pathway inactivation, which ultimately inhibits proliferation and induces caspase-dependent apoptosis in GC cells. Chaetocin therefore may be a potential agent for GC treatment.


2007 ◽  
Vol 30 (4) ◽  
pp. 87
Author(s):  
A. E. Lin ◽  
A. Wakeham ◽  
A. You-Ten ◽  
G. Wood ◽  
T. W. Mak

Ubiquitination is a eukaryotic process of selective proteolysis, where a highly conserved ubiquitin protein is selectively added as a chain to the targeted to a protein for degradation. In recent years, the process of ubiquitination has been shown to be a critical mechanism that can affect essential signalling pathways, including apoptosis, cell cycle arrest and induction of the inflammatory response. Thus, alterations in the ubiquitination process can alter signalling pathways pivotal to numerous disease pathologies. This is clearly demonstrated in perturbations of ubiquitination in the NFκB giving rise to cancer and other immunological disease processes. To gain insight into pathways that require regulation by ubiquitination, our lab has directed focus on the highly conserved E3 ligase, Ariadne 2. Ariadne 2 is characterized as a putative RING finger E3 ligase and is part of the family of highly conserved RBR (RING-B-Box-RING) superfamily. The role of Ariadne 2 has been well studied in Drosophila melanogaster, however, little is known of the function of Ariadne 2 in mammalian systems. Therefore, the main objectives of the project are as follows: To determine the biological role of Ariadne 2, the role of Ariadne 2 in development and differentiation, and the consequences of in vivo loss of Ariadne 2 expression. We are currently investigating the role of Ariadne 2 as an E3 ligase and its involvement in the immune response. To date, we have shown that Ariadne 2 is ubiquitously expressed, especially in the brain, heart, spleen and thymus. For in vivo loss of function analysis, mice were generated by homologous recombination to be deficient for Ariadne 2. These deficient mice die prematurely soon after birth, suggesting a critical role for Ariadne 2 in development and survival. We are currently focusing on the role of Ariadne 2 in development and it’s role in immune pathologies, in particular, spontaneous autoimmunity, using both in vitro studies and in vivo models.


Author(s):  
Samantha Peel ◽  
Mark Jackman

Microphysiological Systems (MPS), often referred to as 'organ-on-chips' are microfluidic-based in vitro models that aim to recapitulate the dynamic chemical and mechanical microenvironment of living organs. MPS promise to bridge the gap between in vitro and in vivo models, and ultimately improve the translation from pre-clinical animal studies to clinical trials. However, despite the explosion of interest in recent years, and the obvious rewards for such models which could improve R&D efficiency and reduce drug attrition in the clinic, the pharmaceutical industry has been slow to fully adopt this technology. The ability to extract robust, quantitative information from MPS at scale is a key requirement if these models are to impact drug discovery and the subsequent drug development process. Microscopy imaging remains a core technology that enables the capture of information at the single cell level and with subcellular resolution. Furthermore, such imaging techniques can be automated, increasing throughput, enabling compound screening. In this review we discuss a range of imaging techniques that have been applied to MPS of varying focus, such as organoids and organ-chip-type models. We outline the opportunities these technologies can bring in terms of understanding mechanistic biology, but also how they could be used in higher-throughput screens, widening the scope of their impact in drug discovery. We discuss the associated challenges of imaging these complex models and the steps required to enable full exploitation. Finally, we discuss the requirements for MPS, if they are to be applied at a scale necessary to support drug discovery projects.


ADMET & DMPK ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 267-268
Author(s):  
Klara Livia Valko ◽  
Simon Teague ◽  
Charles Pudgeon

The authors of the original paper published with the same title: ADMET & DMPK 5(1) (2017) 14-38; doi: 10.5599/admet.5.1.373, apologize for the error in the plot on Figure 5. The erratum gives a correct plot.


2021 ◽  
Author(s):  
Ana Claudia dos Santos Pereira Andrade ◽  
Gabriel Henrique Campolina-Silva ◽  
Celso Martins Queiroz-Junior ◽  
Leonardo Camilo de Oliveira ◽  
Larisse de Souza Barbosa Lacerda ◽  
...  

Several animal models are being used to explore important features of COVID-19, nevertheless none of them recapitulates all aspects of the disease in humans. The continuous refinement and development of other options of in vivo models are opportune, especially ones that are carried out at BSL-2 (Biosafety Level 2) laboratories. In this study, we investigated the suitability of the intranasal infection with the murine betacoronavirus MHV-3 to recapitulate multiple aspects of the pathogenesis of COVID-19 in C57BL/6J mice. We demonstrate that MHV-3 replicated in lungs 1 day after inoculation and triggered respiratory inflammation and dysfunction. This MHV-model of infection was further applied to highlight the critical role of TNF in cytokine-mediated coronavirus pathogenesis. Blocking TNF signaling by pharmacological and genetic strategies greatly increased the survival time and reduces lung injury of MHV-3-infected mice. In vitro studies showed that TNF blockage decreased SARS-CoV-2 replication in human epithelial lung cells and resulted in the lower release of IL-6 and IL-8 cytokines beyond TNF itself. Taken together, our results demonstrate that this model of MHV infection in mice is a useful BSL-2 screening platform for evaluating pathogenesis for human coronaviruses infections, such as COVID-19.


2021 ◽  
Author(s):  
Parichehr Hassanzadeh ◽  
Elham Arbabi ◽  
Fatemeh Rostami

Breast cancer therapy has remained one of the major healthcare challenges. Based on the critical role of cyclin-dependent kinase 4/6 (CDK 4/6) in cell cycle progression, targeting this signaling appears promising for cancer therapy. Palbociclib, a selective CDKs 4/6 inhibitor, is the first-line treatment for estrogen receptor-positive breast cancer. However, poor absorption or side effects may negatively affect its efficiency. This prompted us to incorporate palbociclib into the nanostructured lipid carriers (NLCs) and evaluate the anticancer effect of the nanoformulation (Pa-NLCs) in in vitro and in vivo models of breast cancer. Pa-NLCs were developed by high-pressure homogenization followed by assessment of the physicochemical characteristics and bioactivities in MCF-7 breast cancer cells and female Wistar rats exposed to the carcinogen 7,12-dimethylbenz(a)anthracene (DMBA). The prepared Pa-NLCs demonstrated suitable physicochemical characteristics, including the controlled release pattern, efficient cellular uptake, and cytotoxicity, while free palbociclib failed to show significant effects. Rats treated with Pa-NLCs exhibited significantly reduced tumor volumes, increased survival rates, and histopathological improvement. Free palbociclib was significantly less efficient than Pa-NLCs. Pa-NLCs, by improving the pharmacological profile of palbociclib and providing longer-lasting effects, can be considered as a promising nanoformulation against breast cancer.


2011 ◽  
Vol 39 (6) ◽  
pp. 1649-1653 ◽  
Author(s):  
Nadine Suffee ◽  
Benjamin Richard ◽  
Hanna Hlawaty ◽  
Olivier Oudar ◽  
Nathalie Charnaux ◽  
...  

Atherosclerosis is an inflammatory disease that is one of the leading causes of death in developed countries. This disease is defined by the formation of an atherosclerotic plaque, which is responsible for artery obstruction and affects the heart by causing myocardial infarction. The vascular wall is composed of three cell types and includes a monolayer of endothelial cells and is irrigated by a vasa vasorum. The formation of the vascular network from the vasa vasorum is a process involved in the destabilization of this plaque. Cellular and molecular approaches are studied by in vitro assay of activated endothelial cells and in in vivo models of neovascularization. Chemokines are a large family of small secreted proteins that have been shown to play a critical role in the regulation of angiogenesis during several pathophysiological processes such as ischaemia. Chemokines may exert their regulatory activity on angiogenesis directly by activating the vasa vasorum, or as a consequence of leucocyte infiltration through the endothelium, and/or by the induction of growth factor expression such as that of VEGF (vascular endothelial growth factor). The present review focuses on the angiogenic activity of the chemokines RANTES (regulated upon activation, normal T-cell expressed and secreted)/CCL5 (CC chemokine ligand 5). RANTES/CCL5 is released by many cell types such as platelets or smooth muscle cells. This chemokine interacts with GPCRs (G-protein-coupled receptors) and GAG (glycosaminoglycan) chains bound to HSPGs (heparan sulfate proteoglycans). Many studies have demonstrated, using RANTES/CCL5 mutated on their GAG or GPCR-binding sites, the involvement of these chemokines in angiogenic process. In the present review, we discuss two controversial roles of RANTES/CCL5 in the angiogenic process.


2017 ◽  
Vol 22 (5) ◽  
pp. 583-601 ◽  
Author(s):  
P. Marc D. Watson ◽  
Edel Kavanagh ◽  
Gary Allenby ◽  
Matthew Vassey

Neurodegeneration and neuroinflammation are key features in a range of chronic central nervous system (CNS) diseases such as Alzheimer’s and Parkinson’s disease, as well as acute conditions like stroke and traumatic brain injury, for which there remains significant unmet clinical need. It is now well recognized that current cell culture methodologies are limited in their ability to recapitulate the cellular environment that is present in vivo, and there is a growing body of evidence to show that three-dimensional (3D) culture systems represent a more physiologically accurate model than traditional two-dimensional (2D) cultures. Given the complexity of the environment from which cells originate, and their various cell–cell and cell–matrix interactions, it is important to develop models that can be controlled and reproducible for drug discovery. 3D cell models have now been developed for almost all CNS cell types, including neurons, astrocytes, microglia, and oligodendrocyte cells. This review will highlight a number of current and emerging techniques for the culture of astrocytes and microglia, glial cell types with a critical role in neurodegenerative and neuroinflammatory conditions. We describe recent advances in glial cell culture using electrospun polymers and hydrogel macromolecules, and highlight how these novel culture environments influence astrocyte and microglial phenotypes in vitro, as compared to traditional 2D systems. These models will be explored to illuminate current trends in the techniques used to create 3D environments for application in research and drug discovery focused on astrocytes and microglial cells.


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