scholarly journals A Review on SARS-CoV-2 Virology, Pathophysiology, Animal Models, and Anti-Viral Interventions

Pathogens ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 426 ◽  
Author(s):  
Sabari Nath Neerukonda ◽  
Upendra Katneni

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of CoV disease 2019 (COVID-19) is a highly pathogenic and transmissible CoV that is presently plaguing the global human population and economy. No proven effective antiviral therapy or vaccine currently exists, and supportive care remains to be the cornerstone treatment. Through previous lessons learned from SARS-CoV-1 and MERS-CoV studies, scientific groups worldwide have rapidly expanded the knowledge pertaining to SARS-CoV-2 virology that includes in vitro and in vivo models for testing of antiviral therapies and randomized clinical trials. In the present narrative, we review SARS-CoV-2 virology, clinical features, pathophysiology, and animal models with a specific focus on the antiviral and adjunctive therapies currently being tested or that require testing in animal models and randomized clinical trials.

Author(s):  
Sabarinath Neerukonda ◽  
Upendra Katneni

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of CoV disease 2019 (COVID-19) is a highly pathogenic and transmissible CoV that is presently plaguing the global human population and economy. No proven effective anti-viral therapy or vaccine currently exist, and supportive care remains to be the cornerstone treatment. Through previous lessons learned from SARS-CoV-1 and MERS-CoV studies, scientific groups worldwide have rapidly expanded the knowledge pertaining to SARS-CoV-2 virology that included in vitro and in vivo models for testing of anti-viral therapies, and randomized clinical trials. In the present narrative, we review SARS-CoV-2 virology, clinical features, pathophysiology, and animal models with a specific focus on anti-viral and adjunctive therapies currently being tested or require testing in animal models and randomized clinical trials.


Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1382
Author(s):  
Mina Martini ◽  
Iolanda Altomonte ◽  
Domenico Tricò ◽  
Riccardo Lapenta ◽  
Federica Salari

The increase of knowledge on the composition of donkey milk has revealed marked similarities to human milk, which led to a growing number of investigations focused on testing the potential effects of donkey milk in vitro and in vivo. This paper examines the scientific evidence regarding the beneficial effects of donkey milk on human health. Most clinical studies report a tolerability of donkey milk in 82.6–98.5% of infants with cow milk protein allergies. The average protein content of donkey milk is about 18 g/L. Caseins, which are main allergenic components of milk, are less represented compared to cow milk (56% of the total protein in donkey vs. 80% in cow milk). Donkey milk is well accepted by children due to its high concentration of lactose (about 60 g/L). Immunomodulatory properties have been reported in one study in humans and in several animal models. Donkey milk also seems to modulate the intestinal microbiota, enhance antioxidant defense mechanisms and detoxifying enzymes activities, reduce hyperglycemia and normalize dyslipidemia. Donkey milk has lower calorie and fat content compared with other milks used in human nutrition (fat ranges from 0.20% to 1.7%) and a more favourable fatty acid profile, being low in saturated fatty acids (3.02 g/L) and high in alpha-linolenic acid (about 7.25 g/100 g of fat). Until now, the beneficial properties of donkey milk have been mostly related to whey proteins, among which β-lactoglobulin is the most represented (6.06 g/L), followed by α-lactalbumin (about 2 g/L) and lysozyme (1.07 g/L). So far, the health functionality of donkey milk has been tested almost exclusively on animal models. Furthermore, in vitro studies have described inhibitory action against bacteria, viruses, and fungi. From the literature review emerges the need for new randomized clinical trials on humans to provide stronger evidence of the potential beneficial health effects of donkey milk, which could lead to new applications as an adjuvant in the treatment of cardiometabolic diseases, malnutrition, and aging.


Author(s):  
Zachary Fralish ◽  
Ethan M. Lotz ◽  
Taylor Chavez ◽  
Alastair Khodabukus ◽  
Nenad Bursac

The neuromuscular junction (NMJ) is a specialized cholinergic synaptic interface between a motor neuron and a skeletal muscle fiber that translates presynaptic electrical impulses into motor function. NMJ formation and maintenance require tightly regulated signaling and cellular communication among motor neurons, myogenic cells, and Schwann cells. Neuromuscular diseases (NMDs) can result in loss of NMJ function and motor input leading to paralysis or even death. Although small animal models have been instrumental in advancing our understanding of the NMJ structure and function, the complexities of studying this multi-tissue system in vivo and poor clinical outcomes of candidate therapies developed in small animal models has driven the need for in vitro models of functional human NMJ to complement animal studies. In this review, we discuss prevailing models of NMDs and highlight the current progress and ongoing challenges in developing human iPSC-derived (hiPSC) 3D cell culture models of functional NMJs. We first review in vivo development of motor neurons, skeletal muscle, Schwann cells, and the NMJ alongside current methods for directing the differentiation of relevant cell types from hiPSCs. We further compare the efficacy of modeling NMDs in animals and human cell culture systems in the context of five NMDs: amyotrophic lateral sclerosis, myasthenia gravis, Duchenne muscular dystrophy, myotonic dystrophy, and Pompe disease. Finally, we discuss further work necessary for hiPSC-derived NMJ models to function as effective personalized NMD platforms.


2021 ◽  
Vol 9 (7) ◽  
pp. e002503
Author(s):  
Miok Kim ◽  
Yong Ki Min ◽  
Jinho Jang ◽  
Hyejin Park ◽  
Semin Lee ◽  
...  

BackgroundAlthough cancer immunotherapy is one of the most effective advanced-stage cancer therapies, no clinically approved cancer immunotherapies currently exist for colorectal cancer (CRC). Recently, programmed cell death protein 1 (PD-1) blockade has exhibited clinical benefits according to ongoing clinical trials. However, ongoing clinical trials for cancer immunotherapies are focused on PD-1 signaling inhibitors such as pembrolizumab, nivolumab, and atezolizumab. In this study, we focused on revealing the distinct response mechanism for the potent CD73 ectoenzyme selective inhibitor AB680 as a promising drug candidate that functions by blocking tumorigenic ATP/adenosine signaling in comparison to current therapeutics that block PD-1 to assess the value of this drug as a novel immunotherapy for CRC.MethodsTo understand the distinct mechanism of AB680 in comparison to that of a neutralizing antibody against murine PD-1 used as a PD-1 blocker, we performed single-cell RNA sequencing of CD45+ tumor-infiltrating lymphocytes from untreated controls (n=3) and from AB680-treated (n=3) and PD-1-blockade-treated murine CRC in vivo models. We also used flow cytometry, Azoxymethane (AOM)/Dextran Sulfate Sodium (DSS) models, and in vitro functional assays to validate our new findings.ResultsWe initially observed that the expressions of Nt5e (a gene for CD73) and Entpd1 (a gene for CD39) affect T cell receptor (TCR) diversity and transcriptional profiles of T cells, thus suggesting their critical roles in T cell exhaustion within tumor. Importantly, PD-1 blockade significantly increased the TCR diversity of Entpd1-negative T cells and Pdcd1-positive T cells. Additionally, we determined that AB680 improved the anticancer functions of immunosuppressed cells such as Treg and exhausted T cells, while the PD-1 blocker quantitatively reduced Malat1high Treg and M2 macrophages. We also verified that PD-1 blockade induced Treg depletion in AOM/DSS CRC in vivo models, and we confirmed that AB680 treatment caused increased activation of CD8+ T cells using an in vitro T cell assay.ConclusionsThe intratumoral immunomodulation of CD73 inhibition is distinct from PD-1 inhibition and exhibits potential as a novel anticancer immunotherapy for CRC, possibly through a synergistic effect when combined with PD-1 blocker treatments. This study may contribute to the ongoing development of anticancer immunotherapies targeting refractory CRC.


2000 ◽  
Vol 11 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Olaf Weber ◽  
Jürgen Reefschläger ◽  
Helga Rübsamen-Waigmann ◽  
Siegfried Raddatz ◽  
Matthias Hesseling ◽  
...  

Novel peptide aldehydes (PAs) were identified as potent inhibitors of human cytomegalovirus (HCMV) in vitro. Although these compounds were highly effective against HCMV, they did not exhibit any activity against murine cytomegalovirus (MCMV). The purpose of this study was to test the antiviral activity of PA 8 as a representative of this novel class of inhibitors against HCMV in vivo. Because of the strict species specificity of HCMV we had to use two artificial animal models. In the first model, HCMV-infected human cells were entrapped into agarose plugs and transplanted into mice. In the second model, SCID mice were transplanted with human tissues that were subsequently infected with a clinical isolate of HCMV. In these two models the antiviral activity of PA 8 was clearly demonstrated, ganciclovir only being slightly superior in its in vivo antiviral activity.


2020 ◽  
Vol 21 (14) ◽  
pp. 4993 ◽  
Author(s):  
Raphael Mohr ◽  
Burcin Özdirik ◽  
Jana Knorr ◽  
Alexander Wree ◽  
Münevver Demir ◽  
...  

Cholangiocarcinoma (CCA) comprises a heterogeneous group of primary liver tumors. They emerge from different hepatic (progenitor) cell populations, typically via sporadic mutations. Chronic biliary inflammation, as seen in primary sclerosing cholangitis (PSC), may trigger CCA development. Although several efforts were made in the last decade to better understand the complex processes of biliary carcinogenesis, it was only recently that new therapeutic advances have been achieved. Animal models are a crucial bridge between in vitro findings on molecular or genetic alterations, pathophysiological understanding, and new therapeutic strategies for the clinic. Nevertheless, it is inherently difficult to recapitulate simultaneously the stromal microenvironment (e.g., immune-competent cells, cholestasis, inflammation, PSC-like changes, fibrosis) and the tumor biology (e.g., mutational burden, local growth, and metastatic spread) in an animal model, so that it would reflect the full clinical reality of CCA. In this review, we highlight available data on animal models for CCA. We discuss if and how these models reflect human disease and whether they can serve as a tool for understanding the pathogenesis, or for predicting a treatment response in patients. In addition, open issues for future developments will be discussed.


Viruses ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1116
Author(s):  
Emna Benzarti ◽  
Mutien Garigliany

Usutu virus (USUV), a mosquito-borne zoonotic flavivirus discovered in South Africa in 1959, has spread to many European countries over the last 20 years. The virus is currently a major concern for animal health due to its expanding host range and the growing number of avian mass mortality events. Although human infections with USUV are often asymptomatic, they are occasionally accompanied by neurological complications reminiscent of those due to West Nile virus (another flavivirus closely related to USUV). Whilst USUV actually appears less threatening than some other emergent arboviruses, the lessons learned from Chikungunya, Dengue, and Zika viruses during the past few years should not be ignored. Further, it would not be surprising if, with time, USUV disperses further eastwards towards Asia and possibly westwards to the Americas, which may result in more pathogenic USUV strains to humans and/or animals. These observations, inviting the scientific community to be more vigilant about the spread and genetic evolution of USUV, have prompted the use of experimental systems to understand USUV pathogenesis and to boost the development of vaccines and antivirals. This review is the first to provide comprehensive coverage of existing in vitro and in vivo models for USUV infection and to discuss their contribution in advancing data concerning this neurotropic virus. We believe that this paper is a helpful tool for scientists to identify gaps in the knowledge about USUV and to design their future experiments to study the virus.


2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 3040-3040 ◽  
Author(s):  
H. K. Hariharan ◽  
T. Murphy ◽  
D. Clanton ◽  
L. Berquist ◽  
P. Chu ◽  
...  

3040 Background: Galiximab, a primatized monoclonal antibody that binds with high affinity to CD80 and mediates antibody- dependent, cell-mediated cytotoxicity in vitro, is currently under investigation for the treatment of follicular non-Hodgkin’s lymphoma (NHL). In a phase I/II monotherapy study, galiximab produced an overall response rate of 11%, and tumor reductions were observed in 46% of patients. Initial clinical trials also demonstrate that galiximab is well tolerated and suggest that combining galiximab with rituximab (anti-CD20) provides clinical benefit. These results are consistent with preclinical studies in murine lymphoma xenograft model systems, which demonstrate the superiority of combination therapy. Methods: To further define the therapeutic potential of galiximab, the Raji subcutaneous and the SKW disseminated lymphoma murine xenograft models were used to define the in vivo efficacy of galiximab alone or in combination with fludarabine or doxorubicin. Similar studies were performed with rituximab. Results: In the Raji model, both galiximab and rituximab exhibited maximal inhibition of the growth of preestablished (150-mg) tumors at a dose of 3 mg/kg/wk. Interestingly, higher doses of galiximab (but not rituximab) showed reduced inhibition. Galiximab (3 mg/kg/wk) inhibited tumor growth alone (P<0.0001 vs. control) and showed significantly enhanced activity when combined with fludarabine (50 or 100 mg/kg daily for 5 days; P<0.0002 vs. galiximab alone and P<0.003 vs. fludarabine alone). Similar results were observed with rituximab. In the SKW model, treatment with galiximab (5 mg/kg/wk for 6 doses) significantly enhanced survival compared with a control (P<0.0001) or doxorubicin (2.5 mg/kg/day for 3 doses; P<0.0001). Studies combining fludarabine or doxorubicin with both galiximab and rituximab are ongoing. Conclusions: Studies in animal models of lymphoma indicate that galiximab may provide clinical benefit when used in combination with chemotherapeutic agents such as fludarabine and doxorubicin, and provide a rationale for the investigation of these novel chemoimmunotherapy combinations in clinical trials. No significant financial relationships to disclose.


2020 ◽  
Vol 9 (2) ◽  
pp. 264-272
Author(s):  
A. I. Shpichko ◽  
O. A. Grebenchikov ◽  
I. V. Molchanov ◽  
A. K. Shabanov ◽  
N. P. Shpichko ◽  
...  

Abstract The review presents the main aspects of the cardioprotective properties of the xenon inhalation anesthetic. Based on the analysis of publications, the article discusses modern views on the mechanisms of the protective action of xenon, realized using pre- and post-conditioning mechanisms, shows major molecular targets and their effects. The article presents the results of experimental studies in vivo and in vitro, which showed the protective effect of xenon on the myocardium and the results of recent randomized clinical trials. The analysis of studies demonstrates the ability of xenon to increase myocardial resistance to ischemia and reperfusion and opens up good prospects for its use in clinical practice in patients with a high risk of cardiac complications.


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