Role of Toll-like receptors in COVID-19 pathogenesis

Introduction. This review summarizes the available information on the role of Toll-like receptors (TLRs) in the pathogenesis of the novel coronavirus infection COVID-19 induced by SARS-CoV-2. The exact pathogenesis of COVID-19 and the role of each component of innate and adaptive immunity are still unknown. Aim. Discussion of the possible role of TLRs in the immune response in COVID-19 infection. Results. Analysis of the literature in the PubMed database showed that the mechanism of penetration of SARS-CoV-2 and lysis of type II alveolocytes is the binding of the spike S-glycoprotein or capsid protein M of the virus to the receptor-binding domain of ACE2 on the surface of epithelial cells. Migration and infiltration of inflammatory cells leads to overactivation of TLR4 on the surface of alveolocytes and bronchial epithelium, shifting the process to MyD88-dependent acute inflammatory signaling and hypersecretion of proinflammatory cytokines that cause a “cytokine storm” and the development of severe complications of COVID-19 infection, in particular, acute respiratory infections, respiratory distress syndrome, pathology of internal organs, and, in some cases, the death of the patient. Conclusion. It is possible to suggest that TLRs have an impact on the immune response in COVID19 infection. Both antagonists and agonists of TLRs, depending on their type, can be examined to determine the therapeutic and negative effects of COVID-19 infection. Further research is needed to investigate TLRs and pathways for activating cytokine expression, as they indicate a direct relationship with mortality and virus susceptibility. Bioinformatic research can also help to better understand the interaction of TLRs with proteins and RNA of the SARS-CoV-2.

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Mesenchymal Stem Cells: The Secret Children’s Weapons against the SARS-CoV-2 Lethal Infection

Applied Sciences ◽

10.3390/app11041696 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1696

Author(s):

Mario Giosuè Balzanelli ◽

Pietro Distratis ◽

Orazio Catucci ◽

Angelo Cefalo ◽

Rita Lazzaro ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Respiratory Infections ◽

Acute Respiratory Infections ◽

Unusual Event ◽

Inflammatory Processes ◽

Life Threatening ◽

Severe Acute Respiratory Infections ◽

Novel Coronavirus

Due to the promising effects of mesenchymal stem cells (MSCs) in the treatment of various diseases, this commentary aimed to focus on the auxiliary role of MSCs to reduce inflammatory processes of acute respiratory infections caused by the 2019 novel coronavirus (COVID-19). Since early in 2020, COVID-19, a consequence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly affected millions of people world-wide. The SARS-CoV-2 infection in children appears to be an unusual event. Despite the high number of affected adult and elderly, children and adolescents remained low in amounts, and marginally touched. Based on the promising role of cell therapy and regenerative medicine approaches in the treatment of several life-threatening diseases, it seems that applying MSCs cell-based approaches can also be a hopeful strategy for improving subjects with severe acute respiratory infections caused by COVID-19.

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Role of Toll-Like Receptors in the Innate Immune Response to RNA Viruses

Cellular Signaling and Innate Immune Responses to RNA Virus Infections ◽

10.1128/9781555815561.ch2 ◽

2014 ◽

pp. 7-27

Author(s):

Andrew G. Bowie ◽

Sinéad E. Keating

Keyword(s):

Immune Response ◽

Innate Immune Response ◽

Rna Viruses ◽

Innate Immune ◽

Toll Like Receptors

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097 Innate immune response to the respiratory bacteria Burkholderia cenocepacia: role of the Toll-like receptors

Revue des Maladies Respiratoires ◽

10.1016/s0761-8425(06)71925-8 ◽

2006 ◽

Vol 23 (5) ◽

pp. 563

Author(s):

G. Ventura ◽

R. Le Goffic ◽

V. Balloy ◽

M.C. Plotkowski ◽

M. Chignard ◽

...

Keyword(s):

Immune Response ◽

Innate Immune Response ◽

Innate Immune ◽

Burkholderia Cenocepacia ◽

Toll Like Receptors

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Role of Cytokines and Toll-Like Receptors in the Immunopathogenesis of Guillain-Barré Syndrome

Mediators of Inflammation ◽

10.1155/2014/758639 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 21

Author(s):

Kishan Kumar Nyati ◽

Kashi Nath Prasad

Keyword(s):

Immune Response ◽

Single Agent ◽

Host Factors ◽

Guillain Barre Syndrome ◽

Toll Like Receptors ◽

Guillain Barré Syndrome ◽

Microbial Infections ◽

Inflammatory Processes ◽

Guillain Barré

Guillain-Barré syndrome (GBS) is an autoimmune disease of the peripheral nervous system, mostly triggered by an aberrant immune response to an infectious pathogen. Although several infections have been implicated in the pathogenesis of GBS, not all such infected individuals develop this disease. Moreover, infection with a single agent might also lead to different subtypes of GBS emphasizing the role of host factors in the development of GBS. The host factors regulate a broad range of inflammatory processes that are involved in the pathogenesis of autoimmune diseases including GBS. Evidences suggest that systemically and locally released cytokines and their involvement in immune-mediated demyelination and axonal damage of peripheral nerves are important in the pathogenesis of GBS. Toll-like receptors (TLRs) link innate and adaptive immunity through transcription of several proinflammatory cytokines. TLR genes may increase susceptibility to microbial infections; an attenuated immune response towards antigen and downregulation of cytokines occurs due to mutation in the gene. Herein, we discuss the crucial role of host factors such as cytokines and TLRs that activate the immune response and are involved in the pathogenesis of the disease.

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Effect of CAP10 gene on immune response in mice infected with Cryptococcus neoformans

10.21203/rs.2.12042/v1 ◽

2019 ◽

Author(s):

Ni Lin ◽

Liping Lin ◽

Xiaoyu Li ◽

Xianghui Li ◽

Juan Wu ◽

...

Keyword(s):

Immune Response ◽

Immune Responses ◽

Cryptococcus Neoformans ◽

Histopathological Examination ◽

Inflammatory Cells ◽

Expression Plasmid ◽

Shrna Expression ◽

Molecular Therapeutic ◽

Capsular Formation

Abstract ABSTRACT Background Capsule is an vital virulence factor in Cryptococcus neoformans infection. Recent studies show CAP10 is a key gene in capsular formation. However, the role of CAP10 in the pathophysiology of cryptococcosis is still not well understood. This study aims to investigate the association of CAP10 expression with the immune responses to infected mice. Methods The shRNA expression plasmid was designed to interfere with the synthesis of CAP10. The animal model was established with C. neoformans wt strain H99, cap10-shRNA C. neoformans and PBS control in the respiratory tract. On the 7 days and 21 days after infection, mice lung histopathological examination and homogenate culture were performed, and cytokines expression level in the serum of mice were quantitatively detected. Results The lower degree of edema and infiltration of inflammatory cells were observed in cap10-shRNA group. The growth rate of cap10-shRNA strain was significantly reduced. In addition, interference with CAP10 altered the expression profile of Th1, Th2, Th17 and Treg type cytokine. Down-regulation of CAP10 was beneficial to the balance of Th1/Th2, Th17/Treg ratio. Conclusions Taken together, our results indicated the expression of the CAP10 was associated with an antifungal immune response to mice infected with C. neoformans. CAP10 might play an important role in regulating the inflammatory response, and could expected to be a new molecular therapeutic target in cryptococcosis.

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The Role of Herbal and Nutritional Treatments in the Fight against COVID-19 and Other Respiratory Tract Infections

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182212001 ◽

2021 ◽

Vol 18 (22) ◽

pp. 12001

Author(s):

Aline El Zakhem ◽

May Annie Chalhoub ◽

Maya Bassil

Keyword(s):

Respiratory Tract Infections ◽

Respiratory Infections ◽

The Novel ◽

Medical Treatments ◽

Nutritional Interventions ◽

Chinese Herbal ◽

Upper Respiratory ◽

Novel Coronavirus ◽

Tract Infections

With the growing spread of COVID-19 worldwide, the appeal to alternative and nutritional therapies in conjunction with medical therapies has been heightened. This article aims to review studies assessing the roles of Chinese traditional medicine and nutrition in upper respiratory infections, including COVID-19. Various Chinese herbal protocols have been shown to fight respiratory infections, with several having been tested on the novel coronavirus. Additionally, promising findings have been reported when medical treatments were complemented with nutritional interventions. Supplementation with vitamins C and D, Zinc and Selenium are discussed, in addition to certain phytochemicals and food that also possess immunoregulatory and antiviral properties. Further clinical studies are needed to establish these alternative treatments as part of the management of emerging respiratory infections.

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Caffeine as a Factor Influencing the Functioning of the Human Body—Friend or Foe?

Nutrients ◽

10.3390/nu13093088 ◽

2021 ◽

Vol 13 (9) ◽

pp. 3088

Author(s):

Kamil Rodak ◽

Izabela Kokot ◽

Ewa Maria Kratz

Keyword(s):

Human Body ◽

The Elderly ◽

Negative Effects ◽

Caffeine Consumption ◽

The Central Nervous System ◽

Disease Entities ◽

The Individual ◽

Available Information ◽

The Impact

Nowadays, caffeine is one of the most commonly consumed substances, which presents in many plants and products. It has both positive and negative effects on the human body, and its activity concerns a variety of systems including the central nervous system, immune system, digestive system, respiratory system, urinary tract, etc. These effects are dependent on quantity, the type of product in which caffeine is contained, and also on the individual differences among people (sex, age, diet etc.). The main aim of this review was to collect, present, and analyze the available information including the latest discoveries on the impact of caffeine on human health and the functioning of human body systems, taking into account the role of caffeine in individual disease entities. We present both the positive and negative sides of caffeine consumption and the healing properties of this purine alkaloid in diseases such as asthma, Parkinson’s disease, and others, not forgetting about the negative effects of excess caffeine (e.g., in people with hypertension, children, adolescents, and the elderly). In summary, we can conclude, however, that caffeine has a multi-directional influence on various organs of the human body, and because of its anti-oxidative properties, it was, and still is, an interesting topic for research studies including those aimed at developing new therapeutic strategies.

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From Innate to Adaptive Immune Response in Muscular Dystrophies and Skeletal Muscle Regeneration: The Role of Lymphocytes

BioMed Research International ◽

10.1155/2014/438675 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 33

Author(s):

Luca Madaro ◽

Marina Bouché

Keyword(s):

Skeletal Muscle ◽

Immune Response ◽

Immune Cells ◽

Current Knowledge ◽

Adaptive Immune Response ◽

Inflammatory Cells ◽

Skeletal Muscle Regeneration ◽

Current View ◽

Muscle Necrosis

Skeletal muscle is able to restore contractile functionality after injury thanks to its ability to regenerate. Following muscle necrosis, debris is removed by macrophages, and muscle satellite cells (MuSCs), the muscle stem cells, are activated and subsequently proliferate, migrate, and form muscle fibers restoring muscle functionality. In most muscle dystrophies (MDs), MuSCs fail to properly proliferate, differentiate, or replenish the stem cell compartment, leading to fibrotic deposition. However, besides MuSCs, interstitial nonmyogenic cells and inflammatory cells also play a key role in orchestrating muscle repair. A complete understanding of the complexity of these mechanisms should allow the design of interventions to attenuate MDs pathology without disrupting regenerative processes. In this review we will focus on the contribution of immune cells in the onset and progression of MDs, with particular emphasis on Duchenne muscular dystrophy (DMD). We will briefly summarize the current knowledge and recent advances made in our understanding of the involvement of different innate immune cells in MDs and will move on to critically evaluate the possible role of cell populations within the acquired immune response. Revisiting previous observations in the light of recent evidence will likely change our current view of the onset and progression of the disease.

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Cytokines in disease

Clinical Chemistry ◽

10.1093/clinchem/36.7.1269 ◽

1990 ◽

Vol 36 (7) ◽

pp. 1269-1281 ◽

Cited By ~ 114

Author(s):

J T Whicher ◽

S W Evans

Keyword(s):

Immune Response ◽

Recombinant Dna ◽

Inflammatory Cells ◽

Systemic Response ◽

Therapeutic Applications ◽

Diagnosis And Management ◽

Recombinant Dna Techniques

Abstract Cytokines are peptides used by immune and inflammatory cells to communicate with each other and to control the milieu interieur in which they operate. Recent evidence suggests that they are of immense importance in controlling the local and systemic events of the immune response, inflammation, hemopoiesis, healing, and the systemic response to injury. Many of them can now be measured by immunoassay, and the role of such measurements in the diagnosis and management of disease is actively under investigation. Similarly, the availability of recombinant DNA techniques to produce cytokines in almost unlimited quantities is leading to new and exciting therapeutic applications.

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