Human Defensins from antivirals to vaccine adjuvants: rediscovery of the innate immunity arsenal

2021 ◽  
Vol 28 ◽  
Author(s):  
Luisa Zupin ◽  
Sergio Crovella
Keyword(s):  
Immune Response ◽  
Innate Immunity ◽  
Attractive Alternative ◽  
Vaccine Adjuvants ◽  
Natural Agents ◽  
Virus Inhibition ◽  
In Silico Studies ◽  
Direct Binding ◽  
Human Defensins

: Human defensins are a class of antimicrobial peptides, belonging to the innate immunity system. These peptides are expressed at the level of respiratory tract (both upper and lower) where they represent the first line of defense against pathogens; they are also known for their activity against different viruses, acting through diverse mechanisms, including direct binding to the virus, inhibition of viral replication, and aggregation of virions. It has been recently reported they are also effective against SARS-CoV-2. Moreover, they influence the immune response stimulating it in the challenge against microorganisms. An intriguingly potential application of defensin is related to their use as vaccine adjuvants; indeed, some in silico studies suggested their efficacy in boosting the immune response. Since the long-term persistence of acquired immunity against SARS-CoV-2 triggered by the currently employed vaccines is not known, natural agents with enhancing effects, such as defensins, administered with the vaccine, can be an interesting and attractive alternative.

scholarly journals Innate Immune Response against Hepatitis C Virus: Targets for Vaccine Adjuvants

Vaccines ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 313
Author(s):  
Daniel Sepulveda-Crespo ◽  
Salvador Resino ◽  
Isidoro Martinez
Keyword(s):  
Immune Response ◽  
Innate Immunity ◽  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Innate Immune Response ◽  
Vaccine Development ◽  
Innate Immune ◽  
World Health ◽  
Cell Immune Response ◽  
Vaccine Adjuvants

Despite successful treatments, hepatitis C virus (HCV) infections continue to be a significant world health problem. High treatment costs, the high number of undiagnosed individuals, and the difficulty to access to treatment, particularly in marginalized susceptible populations, make it improbable to achieve the global control of the virus in the absence of an effective preventive vaccine. Current vaccine development is mostly focused on weakly immunogenic subunits, such as surface glycoproteins or non-structural proteins, in the case of HCV. Adjuvants are critical components of vaccine formulations that increase immunogenic performance. As we learn more information about how adjuvants work, it is becoming clear that proper stimulation of innate immunity is crucial to achieving a successful immunization. Several hepatic cell types participate in the early innate immune response and the subsequent inflammation and activation of the adaptive response, principally hepatocytes, and antigen-presenting cells (Kupffer cells, and dendritic cells). Innate pattern recognition receptors on these cells, mainly toll-like receptors, are targets for new promising adjuvants. Moreover, complex adjuvants that stimulate different components of the innate immunity are showing encouraging results and are being incorporated in current vaccines. Recent studies on HCV-vaccine adjuvants have shown that the induction of a strong T- and B-cell immune response might be enhanced by choosing the right adjuvant.

scholarly journals Agonists of Receptors of the Innate Immunity and Defective Viral Particles as New Generation of Adjuvants

2018 ◽  
Vol 17 (1) ◽  
pp. 76-86
Author(s):  
O. A. Svitich ◽  
V. F. Lavrov ◽  
P. I. Kukina ◽  
A. A. Iskandaryan ◽  
L. V. Gankovskaya ◽  
...  
Keyword(s):  
Immune Response ◽  
Innate Immunity ◽  
Poly I:C ◽  
Vaccine Adjuvants ◽  
Toll Like Receptor ◽  
Traditional Methods ◽  
Viral Particles ◽  
Pathogen Recognition Receptors ◽  
Molecular Patterns ◽  
New Generation

Vaccines for many years act as one of the most effective and successfully used medicines. Vaccines obtained by traditional methods contain in their composition live, weakened or killed microorganisms (bacteria, viruses, etc.). Now more often, modern, split, subunit, recombinant, polyvalent and some other types of vaccines are being used. The addition of adjuvants to vaccines generally increases the immune response to their administration. It was established that the formation of postvaccinal immunity begins immediately after the introduction of the vaccine, by activating the factors of innate immunity in the interaction of pathogen-associated molecular patterns (PAMPs), in vaccines, with the pathogen-recognition receptors (PRRs) of the immunocompetent cells of the recipient. It is also shown that PRRs activators, including TOLL-like receptor agonists (TLRs) and poly (I:C) polynucleotide oligomers of inosine and cytidylic acids, have the ability to substantially increase the immunogenicity of vaccines, and attempts are being made to use them creation of new types of adjuvants. Defective interfering viral particles (D-particles, DIPs) are also classed as effective stimulants of innate immunity and can also be considered promising vaccine adjuvants. 

scholarly journals Injury-Induced Innate Immune Response During Segment Regeneration of the Earthworm, Eisenia andrei

2021 ◽  
Vol 22 (5) ◽  
pp. 2363
Author(s):  
Kornélia Bodó ◽  
Zoltán Kellermayer ◽  
Zoltán László ◽  
Ákos Boros ◽  
Bohdana Kokhanyuk ◽  
...  
Keyword(s):  
Immune Response ◽  
Innate Immunity ◽  
Immune Cell ◽  
Scavenger Receptor ◽  
Cell Renewal ◽  
Body Parts ◽  
Eisenia Andrei ◽  
Blastema Formation ◽  
Close Proximity ◽  
Renewal Period

Regeneration of body parts and their interaction with the immune response is a poorly understood aspect of earthworm biology. Consequently, we aimed to study the mechanisms of innate immunity during regeneration in Eisenia andrei earthworms. In the course of anterior and posterior regeneration, we documented the kinetical aspects of segment restoration by histochemistry. Cell proliferation peaked at two weeks and remitted by four weeks in regenerating earthworms. Apoptotic cells were present throughout the cell renewal period. Distinct immune cell (e.g., coelomocyte) subsets were accumulated in the newly-formed blastema in the close proximity of the apoptotic area. Regenerating earthworms have decreased pattern recognition receptors (PRRs) (e.g., TLR, except for scavenger receptor) and antimicrobial peptides (AMPs) (e.g., lysenin) mRNA patterns compared to intact earthworms. In contrast, at the protein level, mirroring regulation of lysenins became evident. Experimental coelomocyte depletion caused significantly impaired cell divisions and blastema formation during anterior and posterior regeneration. These obtained novel data allow us to gain insight into the intricate interactions of regeneration and invertebrate innate immunity.

scholarly journals RhoA- and Actin-Dependent Functions of Macrophages from the Rodent Cardiac Transplantation Model Perspective -Timing Is the Essence

Biology ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 70
Author(s):  
Malgorzata Kloc ◽  
Ahmed Uosef ◽  
Martha Villagran ◽  
Robert Zdanowski ◽  
Jacek Z. Kubiak ◽  
...  
Keyword(s):  
Immune Response ◽  
Circadian Rhythm ◽  
Immune Cells ◽  
Chronic Rejection ◽  
Cardiac Transplantation ◽  
Small Gtpase ◽  
Eukaryotic Cells ◽  
Transplantation Model

The small GTPase RhoA, and its down-stream effector ROCK kinase, and the interacting Rac1 and mTORC2 pathways, are the principal regulators of the actin cytoskeleton and actin-related functions in all eukaryotic cells, including the immune cells. As such, they also regulate the phenotypes and functions of macrophages in the immune response and beyond. Here, we review the results of our and other’s studies on the role of the actin and RhoA pathway in shaping the macrophage functions in general and macrophage immune response during the development of chronic (long term) rejection of allografts in the rodent cardiac transplantation model. We focus on the importance of timing of the macrophage functions in chronic rejection and how the circadian rhythm may affect the anti-chronic rejection therapies.

scholarly journals Comparable Long-Term Rabies Immunity in Foxes after IntraMuscular and Oral Application Using a Third-Generation Oral Rabies Virus Vaccine

Vaccines ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 49
Author(s):  
Verena te Kamp ◽  
Virginia Friedrichs ◽  
Conrad M. Freuling ◽  
Ad Vos ◽  
Madlin Potratz ◽  
...  
Keyword(s):  
Immune Response ◽  
Rabies Virus ◽  
Specific Binding ◽  
Lethal Dose ◽  
Genetically Engineered ◽  
Routes Of Administration ◽  
Safety Studies ◽  
Oral Rabies Vaccine ◽  
Cellular Immune

The live genetically-engineered oral rabies virus (RABV) variant SPBN GASGAS induces long-lasting immunity in foxes and protection against challenge with an otherwise lethal dose of RABV field strains both after experimental oral and parenteral routes of administration. Induction of RABV-specific binding antibodies and immunoglobulin isotypes (IgM, total IgG, IgG1, IgG2) were comparable in orally and parenterally vaccinated foxes. Differences were only observed in the induction of virus-neutralizing (VNA) titers, which were significantly higher in the parenterally vaccinated group. The dynamics of rabies-specific antibodies pre- and post-challenge (365 days post vaccination) suggest the predominance of type-1 immunity protection of SPBN GASGAS. Independent of the route of administration, in the absence of IgG1 the immune response to SPBN GAGAS was mainly IgG2 driven. Interestingly, vaccination with SPBN GASGAS does not cause significant differences in inducible IFN-γ production in vaccinated animals, indicating a relatively weak cellular immune response during challenge. Notably, the parenteral application of SPBN GASGAS did not induce any adverse side effects in foxes, thus supporting safety studies of this oral rabies vaccine in various species.

scholarly journals Adaptive Evolution of Relish, a Drosophila NF-κB/IκB Protein

Genetics ◽  
2000 ◽  
Vol 154 (3) ◽  
pp. 1231-1238 ◽  
Author(s):  
David J Begun ◽  
Penn Whitley
Keyword(s):  
Immune Response ◽  
Innate Immunity ◽  
Genetic Analysis ◽  
Adaptive Evolution ◽  
Strong Evidence ◽  
Population Genetic ◽  
Microbial Pathogens ◽  
Population Genetic Analysis ◽  
Evolutionary Conflict ◽  
A Site

Abstract NF-κB and IκB proteins have central roles in regulation of inflammation and innate immunity in mammals. Homologues of these proteins also play an important role in regulation of the Drosophila immune response. Here we present a molecular population genetic analysis of Relish, a Drosophila NF-κB/IκB protein, in Drosophila simulans and D. melanogaster. We find strong evidence for adaptive protein evolution in D. simulans, but not in D. melanogaster. The adaptive evolution appears to be restricted to the IκB domain. A possible explanation for these results is that Relish is a site of evolutionary conflict between flies and their microbial pathogens.

scholarly journals Glycemic Control Potential of Chemically Characterized Extract from Withania frutescens L. Roots in Severe Diabetes-Induced Mice

2021 ◽  
Vol 11 (9) ◽  
pp. 3998
Author(s):  
Abdelfattah El Moussaoui ◽  
Hamza Mechchate ◽  
Mohammed Bourhia ◽  
Imane Es-safi ◽  
Ahmad Mohammad Salamatullah ◽  
...  
Keyword(s):  
Chemical Analysis ◽  
Plant Extract ◽  
Biochemical Parameters ◽  
Pharmaceutical Drugs ◽  
Glucose Lowering ◽  
Natural Agents ◽  
Severe Diabetes ◽  
Treatment Of Diabetes ◽  
Different Doses

Diabetes mellitus is a metabolic syndrome that causes impairment, mortality, and many other complications. Insulin and several synthetic medications are currently used in the treatment of diabetes. However, these pharmaceutical drugs are costly, and therefore medicines place priority on alternatives to fight this lethal disease. This modest study aims to investigate the chemical composition, antidiabetic and antihyperglycemic potentials along with subacute toxicity (bodyweight change and biochemical parameters) of hydroethanol extract from Withania frutescens L. roots (WFRE). The chemical analysis was carried out using GC–MS after extract silylation. The chemical analysis identified many potentially active compounds that may determine the antidiabetic results of WFRE. The antidiabetic effect of WFRE was evaluated in mice with severe diabetes using oral administration of doses up to 400 mg/kg for 28 days. The results of the antidiabetic and antihyperglycemic tests indicate that WFRE possesses promising glucose-lowering effects and, as a result, it may serve as an antidiabetic alternative for long-term use. The 4-week treatments with different doses of plant extract did not alter the bodyweight appearance of the diabetic mice nor their biochemical parameters (AST and ALT). The findings obtained indicate that the studied plant extract controlled severe diabetes in mice. Therefore, Withania frutescens L. can serve society as it provides natural agents to control diabetes.

scholarly journals Bacterial Cyclic Dinucleotides and the cGAS–cGAMP–STING Pathway: A Role in Periodontitis?

Pathogens ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 675
Author(s):  
Samira Elmanfi ◽  
Mustafa Yilmaz ◽  
Wilson W. S. Ong ◽  
Kofi S. Yeboah ◽  
Herman O. Sintim ◽  
...  
Keyword(s):  
Immune Response ◽  
Periodontal Disease ◽  
Innate Immune ◽  
Host Cells ◽  
Type I Interferons ◽  
Type I ◽  
Vaccine Adjuvants ◽  
Cyclic Dinucleotides ◽  
Sting Pathway

Host cells can recognize cytosolic double-stranded DNAs and endogenous second messengers as cyclic dinucleotides—including c-di-GMP, c-di-AMP, and cGAMP—of invading microbes via the critical and essential innate immune signaling adaptor molecule known as STING. This recognition activates the innate immune system and leads to the production of Type I interferons and proinflammatory cytokines. In this review, we (1) focus on the possible role of bacterial cyclic dinucleotides and the STING/TBK1/IRF3 pathway in the pathogenesis of periodontal disease and the regulation of periodontal immune response, and (2) review and discuss activators and inhibitors of the STING pathway as immune response regulators and their potential utility in the treatment of periodontitis. PubMed/Medline, Scopus, and Web of Science were searched with the terms “STING”, “TBK 1”, “IRF3”, and “cGAS”—alone, or together with “periodontitis”. Current studies produced evidence for using STING-pathway-targeting molecules as part of anticancer therapy, and as vaccine adjuvants against microbial infections; however, the role of the STING/TBK1/IRF3 pathway in periodontal disease pathogenesis is still undiscovered. Understanding the stimulation of the innate immune response by cyclic dinucleotides opens a new approach to host modulation therapies in periodontology.

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