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2.
Water Res ; 253: 121354, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38428359

ABSTRACT

DNA-based monitoring of microbial communities that are responsible for the performance of anaerobic digestion of sewage wastes has the potential to improve resource recoveries for wastewater treatment facilities. By treating sludge with propidium monoazide (PMA) prior to amplicon sequencing, this study explored how the presence of DNA from dead microbial biomass carried over with feed sludge may mislead process-relevant biomarkers, and whether primer choice impacts such assessments. Four common primers were selected for amplicon preparation, also to determine if universal primers have sufficient taxonomic or functional coverage for monitoring ecological performance; or whether two domain-specific primers for Bacteria and Archaea are necessary. Anaerobic sludges of three municipal continuously stirred-tank reactors in Victoria, Australia, were sampled at one time-point. A total of 240 amplicon libraries were sequenced on a Miseq using two universal and two domain-specific primer pairs. Untargeted metabolomics was chosen to complement biological interpretation of amplicon gene-based functional predictions. Diversity, taxonomy, phylogeny and functional potentials were systematically assessed using PICRUSt2, which can predict community wide pathway abundance. The two chosen universal primers provided similar diversity profiles of abundant Bacteria and Archaea, compared to the domain-specific primers. About 16 % of all detected prokaryotic genera covering 30 % of total abundances and 6 % of PICRUSt2-estimated pathway abundances were affected by PMA. This showed that dead biomass in the anaerobic digesters impacted DNA-based assessments, with implications for predicting active processes, such as methanogenesis, denitrification or the identification of organisms associated with biological foams. Hence, instead of running two sequencing runs with two different domain-specific primers, we propose conducting PMA-seq with universal primer pairs for routine performance monitoring. However, dead sludge biomass may have some predictive value. In principal component analysis the compositional variation of 239 sludge metabolites resembled that of 'dead-plus-alive' biomass, suggesting that dead organisms contributed to the potentially process-relevant sludge metabolome.


Subject(s)
Biological Monitoring , Sewage , Sewage/microbiology , Anaerobiosis , Bacteria/metabolism , Archaea/metabolism , DNA/metabolism , Victoria , Bioreactors/microbiology , Methane/metabolism , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 16S/metabolism
3.
Adv Ther ; 41(5): 2010-2027, 2024 May.
Article in English | MEDLINE | ID: mdl-38554238

ABSTRACT

INTRODUCTION: For some immune-mediated disorders, despite the range of therapies available there is limited evidence on which treatment sequences are best for patients and healthcare systems. We investigated how their selection can impact outcomes in an Italian setting. METHODS: A 3-year state-transition treatment-sequencing model calculated potential effectiveness improvements and budget reallocation considerations associated with implementing optimal sequences in ankylosing spondylitis (AS), Crohn's disease (CD), non-radiographic axial spondyloarthritis (NR-AxSpA), plaque psoriasis (PsO), psoriatic arthritis (PsA), rheumatoid arthritis (RA), and ulcerative colitis (UC). Sequences included three biological or disease-modifying treatments, followed by best supportive care. Disease-specific response measures were selected on the basis of clinical relevance, data availability, and data quality. Efficacy was differentiated between biologic-naïve and experienced populations, where possible, using published network meta-analyses and real-world data. All possible treatment sequences, based on reimbursement as of December 2022 in Italy (analyses' base country), were simulated. RESULTS: Sequences with the best outcomes consistently employed the most efficacious therapies earlier in the treatment pathway. Improvements to prescribing practice are possible in all diseases; however, most notable was UC, where the per-patient 3-year average treatment failure was 37.3% higher than optimal. The results focused on the three most crowded and prevalent immunological sub-condition diseases in dermatology, rheumatology, and gastroenterology: PsO, RA, and UC, respectively. By prescribing from within the top 20% of the most efficacious sequences, the model found a 15.1% reduction in treatment failures, with a 1.59% increase in drug costs. CONCLUSIONS: Prescribing more efficacious treatments earlier provides a greater opportunity to improve patient outcomes and minimizes treatment failures.


Subject(s)
Arthritis, Psoriatic , Humans , Italy , Arthritis, Psoriatic/drug therapy , Psoriasis/drug therapy , Arthritis, Rheumatoid/drug therapy , Spondylitis, Ankylosing/drug therapy , Treatment Outcome , Colitis, Ulcerative/drug therapy , Crohn Disease/drug therapy , Antirheumatic Agents/therapeutic use
4.
Cytokine ; 178: 156557, 2024 06.
Article in English | MEDLINE | ID: mdl-38452440

ABSTRACT

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a subtype of chronic rhinosinusitis (CRS) characterized by the presence of nasal polyps (NP) in the paranasal mucosa. Despite the complex etiology, NP is believed to result from chronic inflammation. The long-term aftermath of the type 2 response is responsible for symptoms seen in NP patients, i.e. rhinorrhea, hyposmia, and nasal obstruction. Immune cellular tolerogenic mechanisms, particularly CD4 + Foxp3 + regulatory T cells (Tregs), are crucial to curtail inflammatory responses. Current evidence suggests impaired Treg activity is the main reason underlying the compromise of self-tolerance, contributing to the onset of CRSwNP. There is compelling evidence that tumor necrosis factor 2 (TNFR2) is preferentially expressed by Tregs, and TNFR2 is able to identify the most potent suppressive subset of Tregs. Tumor necrosis factor (TNF)-TNFR2 interaction plays a decisive role in the activation and expansion of Tregs. This review summarizes current understanding of Tregs biology, focusing on the discussion of the recent advances in the study of TNF-TNFR2 axis in the upregulation of Treg function as a negative feedback mechanism in the control of chronic inflammation. The role of dysregulation of Tregs in the immunopathogenesis of CRSwNP will be analyzed. The future perspective on the harnessing Tregs-mediated self-tolerant mechanism in the management of CRSwNP will be introduced.


Subject(s)
Nasal Polyps , Neoplasms , Rhinitis , Rhinosinusitis , Sinusitis , Humans , T-Lymphocytes, Regulatory , Receptors, Tumor Necrosis Factor, Type II , Inflammation , Tumor Necrosis Factor-alpha , Chronic Disease , Tumor Microenvironment
5.
J Colloid Interface Sci ; 663: 43-52, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38387185

ABSTRACT

Peptide-based vaccines can trigger highly specific immune responses, although peptides alone are usually unable to confer strong humoral or cellular immunity. Consequently, peptide antigens are administered with immunostimulatory adjuvants, but only a few are safe and effective for human use. To overcome this obstacle, herein a peptide antigen was lipidated to effectively anchor it to liposomes and emulsion. A peptide antigen B cell epitope from Group A Streptococcus M protein was conjugated to a universal T helper epitope, the pan DR-biding epitope (PADRE), alongside a lipidic moiety cholesterol. Compared to a free peptide antigen, the lipidated version (LP1) adopted a helical conformation and self-assembled into small nanoparticles. Surprisingly, LP1 alone induced the same or higher antibody titers than liposomes or emulsion-based formulations. In addition, antibodies produced by mice immunized with LP1 were more opsonic than those induced by administering the antigen with incomplete Freund's adjuvant. No side effects were observed in the immunized mice and no excessive inflammatory immune responses were detected. Overall, this study demonstrated how simple conjugation of cholesterol to a peptide antigen can produce a safe and efficacious vaccine against Group A Streptococcus - the leading cause of superficial infections and the bacteria responsible for deadly post-infection autoimmune disorders.


Subject(s)
Adjuvants, Immunologic , Vaccines , Mice , Humans , Animals , Adjuvants, Immunologic/pharmacology , Adjuvants, Immunologic/chemistry , Lipopeptides/pharmacology , Lipopeptides/chemistry , Liposomes , Emulsions , Epitopes , Streptococcus
6.
Pharmacoecon Open ; 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38289517

ABSTRACT

BACKGROUND: Resistant hypertension (rHTN) is defined as blood pressure (BP) of ≥ 140/90 mmHg despite treatment with at least three antihypertensive medications, including a diuretic. Endovascular ultrasound renal denervation (uRDN) aims to control BP alongside conventional BP treatment with antihypertensive medication. This analysis assesses the cost effectiveness of the addition of the Paradise uRDN System compared with standard of care alone in patients with rHTN from the perspective of the United Kingdom (UK) health care system. METHODS: Using RADIANCE-HTN TRIO trial data, we developed a state-transition model. Baseline risk was calculated using Framingham and Prospective Cardiovascular Münster (PROCAM) risk equations to estimate the long-term cardiovascular risks in patients treated with the Paradise uRDN System, based on the observed systolic BP (SBP) reduction following uRDN. Relative risks sourced from a meta-analysis of randomised controlled trials were then used to project cardiovascular events in patients with baseline SBP ('control' patients); utility and mortality inputs and costs were derived from UK data. Costs and outcomes were discounted at 3.5% per annum. Modelled outcomes were validated against trial meta-analyses and the QRISK3 algorithm and real-world evidence of RDN effectiveness. One-way and probabilistic sensitivity analyses were conducted to assess the uncertainty surrounding the model inputs and sensitivity of the model results to changes in parameter inputs. Results were reported as incremental cost-effectiveness ratios (ICERs). RESULTS: A mean reduction in office SBP of 8.5 mmHg with uRDN resulted in an average improvement in both absolute life-years (LYs) and quality-adjusted life-years (QALYs) gained compared with standard of care alone (0.73 LYs and 0.67 QALYs). The overall base-case ICER with uRDN was estimated at £5600 (€6500) per QALY gained (95% confidence interval £5463-£5739 [€6341-€6661]); modelling demonstrated > 99% probability that the ICER is below the £20,000-£30,000 (€23,214-€34,821) per QALYs gained willingness-to-pay threshold in the UK. Results were consistent across sensitivity analyses and validation checks. CONCLUSIONS: Endovascular ultrasound RDN with the Paradise system offers patients with rHTN, clinicians, and healthcare systems a cost-effective treatment option alongside antihypertensive medication.

7.
Microb Genom ; 9(4)2023 04.
Article in English | MEDLINE | ID: mdl-37079454

ABSTRACT

Globally, the anaerobic bacterium Clostridium perfringens causes severe disease in a wide array of hosts; however, C. perfringens strains are also carried asymptomatically. Accessory genes are responsible for much of the observed phenotypic variation and virulence within this species, with toxins frequently encoded on conjugative plasmids and many isolates carrying up to 10 plasmids. Despite this unusual biology, current genomic analyses have largely excluded isolates from healthy hosts or environmental sources. Accessory genomes, including plasmids, also have often been excluded from broader scale phylogenetic investigations. Here we interrogate a comprehensive collection of 464 C. perfringens genomes and identify the first putative non-conjugative enterotoxin (CPE)-encoding plasmids and a putative novel conjugative locus (Bcp) with sequence similarity to a locus reported from Clostridium botulinum. We sequenced and archived 102 new C. perfringens genomes, including those from rarely sequenced toxinotype B, C, D and E isolates. Long-read sequencing of 11 C. perfringens strains representing all toxinotypes (A-G) identified 55 plasmids from nine distinct plasmid groups. Interrogation of the 464 genomes in this collection identified 1045 plasmid-like contigs from the nine plasmid families, with a wide distribution across the C. perfringens isolates. Plasmids and plasmid diversity play an essential role in C. perfringens pathogenicity and broader biology. We have expanded the C. perfringens genome collection to include temporal, spatial and phenotypically diverse isolates including those carried asymptomatically in the gastrointestinal microbiome. This analysis has resulted in the identification of novel C. perfringens plasmids whilst providing a comprehensive understanding of species diversity.


Subject(s)
Bacterial Toxins , Clostridium perfringens , Humans , Bacterial Toxins/genetics , Phylogeny , Base Composition , Sequence Analysis, DNA , RNA, Ribosomal, 16S , Plasmids/genetics
8.
Vaccines (Basel) ; 11(2)2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36851183

ABSTRACT

Intranasal vaccine administration can overcome the disadvantages of injectable vaccines and present greater efficiency for mass immunization. However, the development of intranasal vaccines is challenged by poor mucosal immunogenicity of antigens and the limited availability of mucosal adjuvants. Here, we examined a number of self-adjuvanting liposomal systems for intranasal delivery of lipopeptide vaccine against group A Streptococcus (GAS). Among them, two liposome formulations bearing lipidated cell-penetrating peptide KALA and a new lipidated chitosan derivative (oleoyl-quaternized chitosan, OTMC) stimulated high systemic antibody titers in outbred mice. The antibodies were fully functional and were able to kill GAS bacteria. Importantly, OTMC was far more effective at stimulating antibody production than the classical immune-stimulating trimethyl chitosan formulation. In a simple physical mixture, OTMC also enhanced the immune responses of the tested vaccine, without the need for a liposome delivery system. The adjuvanting capacity of OTMC was further confirmed by its ability to stimulate cytokine production by dendritic cells. Thus, we discovered a new immune stimulant with promising properties for mucosal vaccine development.

9.
Front Immunol ; 13: 954435, 2022.
Article in English | MEDLINE | ID: mdl-36569921

ABSTRACT

Introduction: COVID-19 pandemic has been threatening public health and economic development worldwide for over two years. Compared with the original SARS-CoV-2 strain reported in 2019, the Omicron variant (B.1.1.529.1) is more transmissible. This variant has 34 mutations in its Spike protein, 15 of which are present in the Receptor Binding Domain (RBD), facilitating viral internalization via binding to the angiotensin-converting enzyme 2 (ACE2) receptor on endothelial cells as well as promoting increased immune evasion capacity. Methods: Herein we compared SARS-CoV-2 proteins (including ORF3a, ORF7, ORF8, Nucleoprotein (N), membrane protein (M) and Spike (S) proteins) from multiple ancestral strains. We included the currently designated original Variant of Concern (VOC) Omicron, its subsequent emerged variants BA.1, BA2, BA3, BA.4, BA.5, the two currently emerging variants BQ.1 and BBX.1, and compared these with the previously circulating VOCs Alpha, Beta, Gamma, and Delta, to better understand the nature and potential impact of Omicron specific mutations. Results: Only in Omicron and its subvariants, a bias toward an Asparagine to Lysine (N to K) mutation was evident within the Spike protein, including regions outside the RBD domain, while none of the regions outside the Spike protein domain were characterized by this mutational bias. Computational structural analysis revealed that three of these specific mutations located in the central core region, contribute to a preference for the alteration of conformations of the Spike protein. Several mutations in the RBD which have circulated across most Omicron subvariants were also analysed, and these showed more potential for immune escape. Conclusion: This study emphasizes the importance of understanding how specific N to K mutations outside of the RBD region affect SARS-CoV-2 conformational changes and the need for neutralizing antibodies for Omicron to target a subset of conformationally dependent B cell epitopes.


Subject(s)
COVID-19 , Lysine , Humans , Lysine/genetics , Asparagine , SARS-CoV-2/genetics , Endothelial Cells , Pandemics , Spike Glycoprotein, Coronavirus/genetics , COVID-19/genetics , Mutation
10.
Vaccines (Basel) ; 10(8)2022 Jul 29.
Article in English | MEDLINE | ID: mdl-36016100

ABSTRACT

Adjuvants and delivery systems are essential components of vaccines to increase immunogenicity against target antigens, particularly for peptide epitopes (poor immunogens). Emulsions, nanoparticles, and liposomes are commonly used as a delivery system for peptide-based vaccines. A Poly(hydrophobic amino acids) delivery system was previously conjugated to Group A Streptococcus (GAS)-derived peptide epitopes, allowing the conjugates to self-assemble into nanoparticles with self adjuvanting ability. Their hydrophobic amino acid tail also serves as an anchoring moiety for the peptide epitope, enabling it to be integrated into the liposome bilayer, to further boost the immunological responses. Polyleucine-based conjugates were anchored to cationic liposomes using the film hydration method and administered to mice subcutaneously. The polyleucine-peptide conjugate, its liposomal formulation, and simple liposomal encapsulation of GAS peptide epitope induced mucosal (saliva IgG) and systemic (serum IgG, IgG1 and IgG2c) immunity in mice. Polyleucine acted as a potent liposome anchoring portion, which stimulated the production of highly opsonic antibodies. The absence of polyleucine in the liposomal formulation (encapsulated GAS peptide) induced high levels of antibody titers, but with poor opsonic ability against GAS bacteria. However, the liposomal formulation of the conjugated vaccine was no more effective than conjugates alone self-assembled into nanoparticles.

11.
Int J Speech Lang Pathol ; 24(3): 283-293, 2022 06.
Article in English | MEDLINE | ID: mdl-35920691

ABSTRACT

Purpose: Papua New Guinea (PNG) has extreme linguistic diversity reflected in its three national languages and sociolinguistic diversity comprising over 380 vernaculars or Tokples, English and the lingua francas, which include Tok Pisin (TP). This first clinical cross-sectional study of consonant acquisition in TP-speaking children sought to identify universal features and the impact of age on phonological development.Method: A local picture naming task was developed and used to elicit a speech sample from 80 children (aged 3;0-6;11). Phonetic and phonemic inventories and developmental phonological processes were analysed across the sample and also in 12-month age groups.Result: Statistically significant differences were found between the Percentage Consonants Correct (PCC) of the 3YO and other age groups. Mean PCC increased with age, but high variation within age groups meant differences were not statistically significant. Universal features observed included the early acquisition of plosives and late mastery of /r/. Language-specific features included processes such as fricatisation and earlier acquisition of /ʤ/ before /s/. Creolisation was seen in morphophonemic condensation and the influence of loanwords.Conclusion: This study demonstrates both universal and language-specific features amidst wide diversity influencing phonological acquisition in creolising TP. This first phonological study of TP consonant development will inform future clinical speech-language pathology practice in PNG.


Subject(s)
Multilingualism , Child , Child Language , Cross-Sectional Studies , Humans , Papua New Guinea , Phonetics , Speech Production Measurement
12.
Biology (Basel) ; 11(8)2022 Aug 17.
Article in English | MEDLINE | ID: mdl-36009853

ABSTRACT

Tamoxifen (TAM) is the most prescribed selective estrogen receptor modulator (SERM) to treat hormone-receptor-positive breast cancer patients and has been used for more than 20 years. Its role as a hormone therapy is well established; however, the potential role in modulating tolerogenic cells needs to be better clarified. Infiltrating tumor-microenvironment-regulatory T cells (TME-Tregs) are important as they serve a suppressive function through the transcription factor Forkhead box P3 (Foxp3). Abundant studies have suggested that Foxp3 regulates the expression of several genes (CTLA-4, PD-1, LAG-3, TIM-3, TIGIT, TNFR2) involved in carcinogenesis to utilize its tumor suppressor function through knockout models. TAM is indirectly concomitant via the Cre/loxP system by allowing nuclear translocation of the fusion protein, excision of the floxed STOP cassette and heritable expression of encoding fluorescent protein in a cohort of cells that express Foxp3. Moreover, TAM administration in breast cancer treatment has shown its effects directly through MDSCs by the enrichment of its leukocyte populations, such as NK and NKT cells, while it impairs the differentiation and activation of DCs. However, the fundamental mechanisms of the reduction of this pool by TAM are unknown. Here, we review the vital effects of TAM on Tregs for a precise mechanistic understanding of cancer immunotherapies.

13.
Front Immunol ; 13: 857812, 2022.
Article in English | MEDLINE | ID: mdl-35651608

ABSTRACT

Glaucoma is an irreversible sight-threatening disorder primarily due to elevated intraocular pressure (IOP), leading to retinal ganglion cell (RGC) death by apoptosis with subsequent loss of optic nerve fibers. A considerable amount of empirical evidence has shown the significant association between tumor necrosis factor cytokine (TNF; TNFα) and glaucoma; however, the exact role of TNF in glaucoma progression remains unclear. Total inhibition of TNF against its receptors can cause side effects, although this is not the case when using selective inhibitors. In addition, TNF exerts its antithetic roles via stimulation of two receptors, TNF receptor I (TNFR1) and TNF receptor II (TNFR2). The pro-inflammatory responses and proapoptotic signaling pathways predominantly mediated through TNFR1, while neuroprotective and anti-apoptotic signals induced by TNFR2. In this review, we attempt to discuss the involvement of TNF receptors (TNFRs) and their signaling pathway in ocular tissues with focus on RGC and glial cells in glaucoma. This review also outlines the potential application TNFRs agonist and/or antagonists as neuroprotective strategy from a therapeutic standpoint. Taken together, a better understanding of the function of TNFRs may lead to the development of a treatment for glaucoma.


Subject(s)
Glaucoma , Receptors, Tumor Necrosis Factor, Type II , Glaucoma/metabolism , Humans , Neuroglia/metabolism , Receptors, Tumor Necrosis Factor, Type I/metabolism , Receptors, Tumor Necrosis Factor, Type II/metabolism , Retinal Ganglion Cells/metabolism
14.
Molecules ; 26(6)2021 Mar 16.
Article in English | MEDLINE | ID: mdl-33809496

ABSTRACT

BACKGROUND: Carnosine is a dipeptide molecule (ß-alanyl-l-histidine) with anti-inflammatory, antioxidant, anti-glycation, and chelating properties. It is used in exercise physiology as a food supplement to increase performance; however, in vitro evidence suggests that carnosine may exhibit anti-cancer properties. METHODS: In this study, we investigated the effect of carnosine on breast, ovarian, colon, and leukemic cancer cell proliferation. We further examined U937 promonocytic, human myeloid leukemia cell phenotype, gene expression, and cytokine secretion to determine if these are linked to carnosine's anti-proliferative properties. RESULTS: Carnosine (1) inhibits breast, ovarian, colon, and leukemic cancer cell proliferation; (2) upregulates expression of pro-inflammatory molecules; (3) modulates cytokine secretion; and (4) alters U937 differentiation and phenotype. CONCLUSION: These effects may have implications for a role for carnosine in anti-cancer therapy.


Subject(s)
Antineoplastic Agents/pharmacology , Carnosine/pharmacology , Dipeptides/pharmacology , Neoplasms/drug therapy , Cell Differentiation/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cytokines/genetics , Gene Expression/drug effects , HT29 Cells , Humans , Neoplasms/genetics , U937 Cells
15.
Front Bioinform ; 1: 709533, 2021.
Article in English | MEDLINE | ID: mdl-36303764

ABSTRACT

COVID-19, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), whilst commonly characterised as a respiratory disease, is reported to have extrapulmonary manifestations in multiple organs. Extrapulmonary involvement in COVID-19 includes autoimmune-like diseases such as Guillain-Barré syndrome and Kawasaki disease, as well as the presence of various autoantibodies including those associated with autoimmune diseases such a systemic lupus erythematosus (e.g. ANA, anti-La). Multiple strains of SARS-CoV-2 have emerged globally, some of which are found to be associated with increased transmissibility and severe disease. We performed an unbiased comprehensive mapping of the potential for cross-reactivity with self-antigens across multiple SARS-CoV-2 proteins and compared identified immunogenic regions across multiples strains. Using the Immune Epitope Database (IEDB) B cell epitope prediction tool, regions predicted as antibody epitopes with high prediction scores were selected. Epitope sequences were then blasted to eight other global strains to identify mutations within these regions. Of the 15 sequences compared, eight had a mutation in at least one other global strain. Predicted epitopes were then compared to human proteins using the NCBI blast tool. In contrast to studies focusing on short sequences of peptide identity, we have taken an immunological approach to selection criteria for further analysis and have identified 136 alignments of 6-23 amino acids (aa) in 129 human proteins that are immunologically likely to be cross-reactive with SARS-CoV-2. Additionally, to identify regions with significant potential to interfere with host cell function-or promote immunopathology, we identified epitope regions more likely to be accessible to pathogenic autoantibodies in the host, selected using a novel combination of sequence similarity, and modelling protein and alignment localization with a focus on extracellular regions. Our analysis identified 11 new predicted B-cell epitopes in host proteins, potentially capable of explaining key aspects of COVID-19 extrapulmonary pathology, and which were missed in other in silico studies which used direct identity rather than immunologically related functional criteria.

16.
Cells ; 9(12)2020 12 08.
Article in English | MEDLINE | ID: mdl-33302501

ABSTRACT

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has recently emerged in China and caused a disease called coronavirus disease 2019 (COVID-19). The virus quickly spread around the world, causing a sustained global outbreak. Although SARS-CoV-2, and other coronaviruses, SARS-CoV and Middle East respiratory syndrome CoV (MERS-CoV) are highly similar genetically and at the protein production level, there are significant differences between them. Research has shown that the structural spike (S) protein plays an important role in the evolution and transmission of SARS-CoV-2. So far, studies have shown that various genes encoding primarily for elements of S protein undergo frequent mutation. We have performed an in-depth review of the literature covering the structural and mutational aspects of S protein in the context of SARS-CoV-2, and compared them with those of SARS-CoV and MERS-CoV. Our analytical approach consisted in an initial genome and transcriptome analysis, followed by primary, secondary and tertiary protein structure analysis. Additionally, we investigated the potential effects of these differences on the S protein binding and interactions to angiotensin-converting enzyme 2 (ACE2), and we established, after extensive analysis of previous research articles, that SARS-CoV-2 and SARS-CoV use different ends/regions in S protein receptor-binding motif (RBM) and different types of interactions for their chief binding with ACE2. These differences may have significant implications on pathogenesis, entry and ability to infect intermediate hosts for these coronaviruses. This review comprehensively addresses in detail the variations in S protein, its receptor-binding characteristics and detailed structural interactions, the process of cleavage involved in priming, as well as other differences between coronaviruses.


Subject(s)
Angiotensin-Converting Enzyme 2/chemistry , Middle East Respiratory Syndrome Coronavirus/metabolism , SARS-CoV-2/metabolism , Severe acute respiratory syndrome-related coronavirus/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Angiotensin-Converting Enzyme 2/metabolism , Binding Sites , COVID-19/pathology , COVID-19/virology , Humans , Middle East Respiratory Syndrome Coronavirus/genetics , Molecular Dynamics Simulation , Protein Structure, Tertiary , Severe acute respiratory syndrome-related coronavirus/genetics , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/metabolism
17.
Hum Immunol ; 81(10-11): 634-643, 2020.
Article in English | MEDLINE | ID: mdl-32771274

ABSTRACT

The interaction of tolerogenic CD103+ dendritic cells (DCs) with regulatory T (Tregs) cells modulates immune responses by inducing immune tolerance. Hence, we determined the proportion of these cells in the peripheral blood mononuclear cells (PBMC) of asthmatic patients. We observed lower trends of CD11b-CD103+ DCs and CD86 within CD11b-CD103+ DCs, while increased levels of Foxp3 expressing CD25+/-TNFR2+ cells in asthmatics. There was a positive correlation in the expression of Foxp3 within CD3+CD4+CD25+TNFR2+ Tregs and CD11b-CD103+ as well as the expression of CD86 within HLA-DR+CD11c+CD11b-CD103+ DCs. In conclusion, we suggest that the increased levels of Tregs in blood could continuously suppress the T helper 2 (Th2) cells activation in the circulation which is also supported by the increase of anti-inflammatory cytokines IL-10 and TNF. Overall, functional immunoregulation of the regulatory cells, particularly Tregs, exhibit immune suppression and induce immune tolerance linked with the immune activation by the antigen presenting cells (APC).


Subject(s)
Antigens, CD/metabolism , Asthma/blood , Asthma/immunology , Dendritic Cells/immunology , Integrin alpha Chains/metabolism , Receptors, Tumor Necrosis Factor, Type II/metabolism , T-Lymphocytes, Regulatory/immunology , Adolescent , Adult , Aged , Cohort Studies , Female , Humans , Immune Tolerance , Interleukin-10/blood , Lymphocyte Activation/immunology , Male , Middle Aged , Th2 Cells/immunology , Tumor Necrosis Factors/blood , Young Adult
18.
Biomolecules ; 10(6)2020 06 18.
Article in English | MEDLINE | ID: mdl-32570769

ABSTRACT

Stingless bees are a type of honey producers that commonly live in tropical countries. Their use for honey is being abandoned due to its limited production. However, the recent improvements in stingless bee honey production, particularly in South East Asia, have brought stingless bee products back into the picture. Although there are many stingless bee species that produce a wide spread of products, known since old eras in traditional medicine, the modern medical community is still missing more investigational studies on stingless bee products. Whereas comprehensive studies in the current era attest to the biological and medicinal properties of honeybee (Apis mellifera) products, the properties of stingless bee products are less known. This review highlights for the first time the medicinal benefits of stingless bee products (honey, propolis, pollen and cerumen), recent investigations and promising future directions. This review emphasizes the potential antioxidant properties of these products that in turn play a vital role in preventing and treating diseases associated with oxidative stress, microbial infections and inflammatory disorders. Summarizing all these data and insights in one manuscript may increase the commercial value of stingless bee products as a food ingredient. This review will also highlight the utility of stingless bee products in the context of medicinal and therapeutic properties, some of which are yet to be discovered.


Subject(s)
Anti-Infective Agents/pharmacology , Antineoplastic Agents, Phytogenic/pharmacology , Antioxidants/pharmacology , Honey/analysis , Animals , Anti-Infective Agents/chemistry , Antineoplastic Agents, Phytogenic/chemistry , Antioxidants/chemistry , Bees , Humans , Molecular Structure
19.
Sci Adv ; 6(5): eaax2285, 2020 01.
Article in English | MEDLINE | ID: mdl-32064333

ABSTRACT

To be optimally effective, peptide-based vaccines need to be administered with adjuvants. Many currently available adjuvants are toxic, not biodegradable; they invariably invoke adverse reactions, including allergic responses and excessive inflammation. A nontoxic, biodegradable, biocompatible, self-adjuvanting vaccine delivery system is urgently needed. Herein, we report a potent vaccine delivery system fulfilling the above requirements. A peptide antigen was coupled with poly-hydrophobic amino acid sequences serving as self-adjuvanting moieties using solid-phase synthesis, to produce fully defined single molecular entities. Under aqueous conditions, these molecules self-assembled into distinct nanoparticles and chain-like aggregates. Following subcutaneous immunization in mice, these particles successfully induced opsonic epitope-specific antibodies without the need of external adjuvant. Mice immunized with entities bearing 15 leucine residues were able to clear bacterial load from target organs without triggering the release of soluble inflammatory mediators. Thus, we have developed a well-defined and effective self-adjuvanting delivery system for peptide antigens.


Subject(s)
Drug Delivery Systems , Inflammation/prevention & control , Vaccines, Subunit/pharmacology , Vaccines/pharmacology , Adjuvants, Immunologic/pharmacology , Amino Acids/chemistry , Amino Acids/immunology , Animals , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Epitopes/drug effects , Epitopes/immunology , Humans , Immunity, Mucosal/immunology , Inflammation/immunology , Mice , Nanoparticles/chemistry , Vaccines/chemistry , Vaccines/immunology , Vaccines, Subunit/chemistry , Vaccines, Subunit/immunology
20.
Cells ; 9(1)2019 12 20.
Article in English | MEDLINE | ID: mdl-31877663

ABSTRACT

Tumor necrosis factor receptor 2 (TNFR2) is expressed on some tumor cells, such as myeloma, Hodgkin lymphoma, colon cancer and ovarian cancer, as well as immunosuppressive cells. There is increasingly evidence that TNFR2 expression in cancer microenvironment has significant implications in cancer progression, metastasis and immune evasion. Although nanomedicine has been extensively studied as a carrier of cancer immunotherapeutic agents, no study to date has investigated TNFR2-targeting nanomedicine in cancer treatment. From an epigenetic perspective, previous studies indicate that DNA demethylation might be responsible for high expressions of TNFR2 in cancer models. This perspective review discusses a novel therapeutic strategy based on nanomedicine that has the capacity to target TNFR2 along with inhibition of DNA demethylation. This approach may maximize the anti-cancer potential of nanomedicine-based immunotherapy and, consequently, markedly improve the outcomes of the management of patients with malignancy.


Subject(s)
Antineoplastic Agents/therapeutic use , DNA Demethylation/drug effects , Neoplasms/drug therapy , Receptors, Tumor Necrosis Factor, Type II/antagonists & inhibitors , Antineoplastic Agents/pharmacology , Drug Synergism , Epigenesis, Genetic/drug effects , Humans , Nanomedicine , Neoplasms/genetics , Neoplasms/metabolism , Signal Transduction/drug effects , Tumor Microenvironment
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