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Antimicrobial peptides (AMPs) have sparked significant interest as potential anti-cancer agents, thereby becoming a focal point in pursuing novel cancer-fighting strategies. These peptides possess distinctive properties, underscoring the importance of developing more potent and selectively targeted versions with diverse mechanisms of action against human cancer cells. Such advancements would offer notable advantages compared to existing cancer therapies. This research aimed to examine the toxicity and selectivity of the nrCap18 peptide in both cancer and normal cell lines. Furthermore, the rate of cellular death was assessed using apoptosis and acridine orange/ethidium bromide (AO/EB) double staining at three distinct incubation times. Additionally, the impact of this peptide on the cancer cell cycle and migration was evaluated, and ultimately, the expression of cyclin-dependent kinase 4/6 (CDK4/6) genes was investigated. The results obtained from the study demonstrated significant toxicity and selectivity in cancer cells compared to normal cells. Moreover, a strong progressive increase in cell death was observed over time. Furthermore, the peptide exhibited the ability to halt the progression of cancer cells in the G1 phase of the cell cycle and impede their migration by suppressing the expression of CDK4/6 genes.
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Apoptose , Neoplasias da Mama , Catelicidinas , Quinase 4 Dependente de Ciclina , Humanos , Animais , Linhagem Celular Tumoral , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Apoptose/efeitos dos fármacos , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/genética , Feminino , Coelhos , Movimento Celular/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Quinase 6 Dependente de Ciclina/metabolismo , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Peptídeos/farmacologia , Peptídeos/química , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacosRESUMO
BACKGROUND: An increase in cancer stem cell (CSC) populations and their resistance to common treatments could be a result of c-Myc dysregulations in certain cancer cells. In the current study, we investigated anticancer effects of c-Myc decoy ODNs loaded-poly (methacrylic acid-co-diallyl dimethyl ammonium chloride) (PMA-DDA)-coated silica nanoparticles as carriers on cancer-like stem cells (NTERA-2). METHODS AND RESULTS: The physicochemical characteristics of the synthesized nanocomposites (SiO2@PMA-DDA-DEC) were analyzed using FT-IR, DLS, and SEM techniques. UV-Vis spectrophotometer was applied to analyze the release pattern of decoy ODNs from the nanocomposite. Furthermore, uptake, cell viability, apoptosis, and cell cycle assays were used to investigate the anticancer effects of nanocomposites loaded with c-Myc decoy ODNs on NTERA-2 cancer cells. The results of physicochemical analytics demonstrated that SiO2@PMA-DDA-DEC nanocomposites were successfully synthesized. The prepared nanocomposites were taken up by NTERA-2 cells with high efficiency, and could effectively inhibit cell growth and increase apoptosis rate in the treated cells compared to the control group. Moreover, SiO2@PMA-DDA nanocomposites loaded with c-Myc decoy ODNs induced cell cycle arrest at the G0/G1 phase in the treated cells. CONCLUSIONS: The conclusion drawn from this study is that c-Myc decoy ODN-loaded SiO2@PMA-DDA nanocomposites can effectively inhibit cell growth and induce apoptosis in NTERA-2 cancer cells. Moreover, given that a metal core is incorporated into this synthetic nanocomposite, it could potentially be used in conjunction with irradiation as part of a decoy-radiotherapy combinational therapy in future investigations.
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Apoptose , Proliferação de Células , Nanopartículas , Células-Tronco Neoplásicas , Proteínas Proto-Oncogênicas c-myc , Humanos , Apoptose/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proliferação de Células/efeitos dos fármacos , Nanopartículas/química , Linhagem Celular Tumoral , Nanocompostos/química , Polieletrólitos/química , Oligodesoxirribonucleotídeos/farmacologia , Oligodesoxirribonucleotídeos/química , Sobrevivência Celular/efeitos dos fármacos , Dióxido de Silício/química , Poliaminas/química , Poliaminas/farmacologia , Ciclo Celular/efeitos dos fármacosRESUMO
This work aimed to purify the proteins that cause blood coagulation in the venom of the Iranian Echis carinatus snake species in a comprehensive manner. Gel filtration chromatography (GFC), Ion exchange chromatography (IEC), and Size Exclusion High-Performance Liquid Chromatography (SEC-HPLC) were utilized in the purification of the coagulation factors. The prothrombin clotting time (PRCT) and SDS-PAGE electrophoresis were performed to confirm the coagulative fractions. The fraction with the shortest coagulation time was selected. The components of this designated fraction were identified through matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF) following thorough purification. Circular dichroism (CD) was employed to determine the second structure of the coagulation factor. The crude venom (CV) was analyzed and had a total protein concentration of 97%. Furthermore, the PRCT of the crude venom solution at a concentration of 1 mg/ml was determined to be 24.19 ± 1.05 s. The dosage administered was found to be a factor in the venom's capacity to induce hemolysis. According to CD analysis, the protein under investigation had a helical structure of 16.7%, a beta structure of 41%, and a turn structure of 9.8%. CHNS proved that the purified coagulant protein had a Carbon content of 77.82%, 5.66% Hydrogen, 3.19% Nitrogen, and 0.49% Sulphur. In the present investigation, a particular type of snake venom metalloproteinase (SVMP) has undergone the process of purification and characterization and has been designated as EC-124. This purified fraction shows significant efficacy as a procoagulant. Our findings have shown that this compound has a function similar to factor X and most likely it can cause blood coagulation by activating factor II (FII).
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OBJECTIVES: Among the most promising antibody formats in terms of inhibiting carcinogenesis are single-stranded variable fragments, whose targeted binding to the Fzd7 receptor has been proven effective at suppressing tumorigenesis. In this study, we investigated the effectiveness of an anti-Fzd7 antibody fragment against both tumor growth and metastasis of breast cancer cells. METHODS: To develop anti-Fzd7 antibodies, bioinformatics approaches were used and the antibodies were expressed recombinantly in E. coli BL21 (DE3). The expression of anti-Fzd7 fragments was verified by Western blotting. Analysis of the antibody's binding capacity to Fzd7 was conducted by flow cytometry. Cell death and apoptosis were assessed by MTT and Annexin V/PI assays. The transwell migration and invasion assays, as well as the scratch method, were used to evaluate cell motility and invasiveness. RESULTS: The anti-Fzd7 antibody was expressed successfully as a single band of 31 kDa. It could bind to 21.5% of MDA-MB-231 cells, as opposed to only 0.54% of SKBR-3 cells as negative control. According to MTT assay, induced apoptosis was 73.7% in MDA-MB-231 cells, compared with 29.5% in SKBR-3 cells. Also, the antibody exerted a significant inhibitory effect of 76% and 58% on migration and invasion of MDA-MB-231 cells, respectively. CONCLUSION: The recombinantly developed anti-Fzd7 scFv of this study could exhibit significant antiproliferative and antimigratory properties, along with a high apoptosis-inducing potential, making it suitable for the immunotherapy of triple negative breast cancer.
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Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Linhagem Celular Tumoral , Neoplasias de Mama Triplo Negativas/patologia , Escherichia coli , Western Blotting , Apoptose , Proliferação de Células , Movimento CelularRESUMO
Monkeypox virus is a member of the Poxviridae family, which causes monkeypox zoonotic disease. Since July 2022, the prevention of monkeypox have become more considerable due to the new outbreak, making it a global concern. Therefore, we used an in silico-based method, including immunoinformatics, bioinformatics, molecular docking, and gene cloning approaches to design a novel multiepitope vaccine against monkeypox. Three immunogenic envelope proteins of monkeypox virus, including G10R, E8L, and A30L, were selected to predict appropriate immune system stimulator epitopes. The A30L is common between smallpox and monkeypox virus, so the proposed vaccine may be effective against smallpox too. There is no evidence of allergenicity and toxicity of the vaccine epitopes. To boost the immunogenicity of the designed vaccine, we used the helper epitope of PADRE and RS01as adjuvants. Furthermore, some linkers are used to link epitopes and adjuvants together. The physicochemical futures of the designed vaccine were assessed. The tertiary structure of the vaccine was modeled and then refined to improve its structure and physicochemical properties. To analyze the vaccine construct and TLR4 complex affinity, they were docked to gather. Besides, the vaccine was cloned into E.coli. pET-21b(+) plasmid to reveal that it can be expressed and stimulate the immune system. Immune stimulation evaluation showed that the candidate vaccine could induce the production of IgM, IgG1, and IgG2 antibodies. Overall, we suggested an effective vaccine candidate against monkeypox. However, Future studies and clinical trials should be done to ensure the efficacy and safety of this vaccine.Communicated by Ramaswamy H. Sarma.
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Mpox , Varíola , Vacinas , Humanos , Imunoinformática , Receptor 4 Toll-Like , Simulação de Acoplamento Molecular , Biologia Computacional , Epitopos , Escherichia coli , Epitopos de Linfócito T , Epitopos de Linfócito B , Vacinas de Subunidades AntigênicasRESUMO
Pneumococcus is the top cause of diseases such as pneumonia/meningitis, and of secondary infections after viral respiratory diseases like COVID-19/flu. Pneumococcal protein-based vaccines consisting of proteins with various functions in virulence might provide a qualified alternative for present vaccines. In this project, PspC, PsaA, and PhtD proteins were considered to anticipate B/T-cell epitopes using immunoinformatics to develop 4 multi-peptide constructs (C, A, and D individual constructs, and a fusion construct CAD). We tested whether vaccination with CAD is able to elicit more efficient protective responses against infection than vaccination with the individual constructs or combination of C + A + D. Based on the in silico results, the constructs were predicted to be antigenic, soluble, non-toxic, and stable, and also be able to provoke humoral/cellular immune reactions. When mice were immunized with the fusion protein, significantly higher levels of IgG and cytokines were induced in serum. The IgG in the fusion group had an effective bioactivity for pneumococcus clearance utilizing the complement pathway. The mice immunized with fusion protein were the most protected from challenge. This report for the first time presents a novel multi-peptide vaccine composed of immunodominant peptides of PspC, PsaA, and PhtD. In general, the experimental results supported the immunoinformatics predictions.
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Infecções Pneumocócicas , Streptococcus pneumoniae , Animais , Camundongos , Proteínas de Bactérias , Vacinas de Subunidades Proteicas , Peptídeos , Epitopos de Linfócito B , Imunoglobulina G , Anticorpos AntibacterianosRESUMO
Enzyme therapy can be an appropriate treatment option for celiac disease (CeD). Here, we developed Bromelain-Loaded Nanocomposites (BLNCs) to improve the stability and retention of bromelain enzyme activity. After the characterization of BLNCs, the cytotoxicity of BLNCs was determined on the Caco-2 cell line. The effect of BLNCs on gliadin degradation and the production of pro-inflammatory cytokines and anti-inflammatory molecules in peripheral blood mononuclear cells (PBMCs) obtained from celiac patients were assessed. Furthermore, the expression of CXCR3 and CCR5 genes was measured in CaCo-2 cells treated with gliadin, gliadin-digested with BLNCs, and bromelain. Our study demonstrated that the Bromelain entrapment efficiency in these nanoparticles was acceptable, and BLNCs have no toxic effect on cells. SDS-PAGE confirmed the digestion effect of bromelain released from nanocomposites. When Caco-2 cells were treated with gliadin digested by free bromelain and BLNCs, the expression of CXCR3 and CCR5 genes was significantly decreased. PBMCs of celiac patients treated with Bromelain and BLNCs decreased inflammatory cytokines (IL-1ß, IL-6, TNF-α, and IFN-γ) production compared to untreated PBMCs. This treatment also increased IL-10 and CTLA-4 in PBMCs of CeD patients. According to the promising results of this study, we can hope for the therapeutic potential of BLNCs for CeD.
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Doença Celíaca , Gliadina , Humanos , Células CACO-2 , Gliadina/metabolismo , Leucócitos Mononucleares/metabolismo , Bromelaínas/farmacologia , Citocinas/metabolismo , Doença Celíaca/tratamento farmacológico , Doença Celíaca/metabolismoRESUMO
Introduction: Pneumococcus is an important respiratory pathogen that is associated with high rates of death in newborn children and the elderly. Given the disadvantages of current polysaccharide-based vaccines, the most promising alternative for developing improved vaccines may be to use protein antigens with different roles in pneumococcus virulence. PspA and PhtD, highly immunogenic surface proteins expressed by almost all pneumococcal strains, are capable of eliciting protective immunity against lethal infections. Methods: In this study using immunoinformatics approaches, we constructed one fusion construct (called PAD) by fusing the immunodominant regions of PspA from families 1 & 2 (PA) to the immunodominant regions of PhtD (PD). The objective of this project was to test the immunogenicity of the fusion protein PAD and to compare its protective activity against S. pneumoniae infection with PA or PD alone and a combination of PA and PD. The prediction of physicochemical properties, antigenicity, allergenicity, toxicity, and 3D-structure of the constructs, as well as molecular docking with HLA receptor and immune simulation were performed using computational tools. Finally, mice were immunized and the serum levels of antibodies/cytokines and functionality of antibodies in vitro were evaluated after immunization. The mice survival rates and decrease of bacterial loads in the blood/spleen were examined following the challenge. Results: The computational analyses indicated the proposed constructs could be antigenic, non-allergenic, non-toxic, soluble and able to elicit robust immune responses. The results of actual animal experiments revealed the candidate vaccines could induce the mice to produce high levels of antibodies and cytokines. The complement-mediated bactericidal activity of antibodies was confirmed and the antibodies provided favorable survival in immunized mice after bacterial challenge. In general, the experimental results verified the immunoinformatics studies. Conclusion: For the first time this report presents novel peptide-based vaccine candidates consisting of immunodominant regions of PspA and PhtD antigens. The obtained findings confirmed that the fusion formulation could be relatively more efficient than the individual and combination formulations. The results propose that the fusion protein alone could be used as a serotype-independent pneumococcal vaccine or as an effective partner protein for a conjugate polysaccharide vaccine.
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Infecções Pneumocócicas , Streptococcus pneumoniae , Humanos , Animais , Camundongos , Recém-Nascido , Idoso , Proteínas de Bactérias , Epitopos/genética , Infecções Pneumocócicas/prevenção & controle , Epitopos Imunodominantes , Simulação de Acoplamento Molecular , Vacinas Pneumocócicas , Vacinas Conjugadas , Anticorpos Antibacterianos , Citocinas , Polissacarídeos , Camundongos Endogâmicos BALB CRESUMO
BACKGROUND: The increasing growth of microbial resistance threatens the health of human societies. Therefore, the discovery and design of new antibiotics seem necessary. Today, antimicrobial peptides (AMPs) are receiving attention due to their unique properties. In our previous studies, exclusive antifungal effects of AurH1, which is a truncated and modified form of Aurein1.2, were synthesized. In this study, AurH1 antifungal peptide was synthesized into acylated (Ac-AurH1) and amidated (AurH1-NH2) derivatives, and their antifungal activity, cytotoxicity, anticancer activity, hemolytic effects were investigated. Finally, the time- of killing, the action mechanism of amidated and acylated peptides, and the effects of salts and human serum on their antimicrobial potency were determined. All the results obtained about these peptides were compared with the AurH1 without chemical modifications. RESULTS: The results showed that amidation at the C-terminal of AurH1 compared to acylation at the N-terminal of it can improve the antifungal properties and cytotoxicity of AurH1. The results showed that AurH1 amidation can maintain the antifungal activity of this peptide in the culture medium containing specific dilutions of human serum compared to the intact AurH1. Also, the amidation of the C-terminal of AurH1 could not affect the mechanism of action and its time -of killing. CONCLUSION: As a result, the amidation of the C-terminal of the AurH1 is a suitable strategy to improve its antifungal properties and cytotoxicity. This modification can enhance its properties for animal studies.
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Anti-Infecciosos , Antifúngicos , Animais , Humanos , Antifúngicos/farmacologia , Peptídeos/farmacologia , Peptídeos/química , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
Available COVID-19 vaccines are primarily based on SARS-CoV-2 spike protein (S). Due to the emergence of new SARS-CoV-2 variants, other virus proteins with more conservancy, such as Membrane (M) protein, are desired for vaccine development. The reverse vaccinology approach was employed to design a multi-epitope SARS-CoV-2 vaccine candidate based on S and M proteins. Cytotoxic T-lymphocyte (CTL), helper T-lymphocyte (HTL), linear B-lymphocyte (LBL) and conformational B-lymphocyte (CBL) of S and M proteins were predicted and screened to choose the best epitopes. A multi-epitope vaccine candidate was constructed using selected CTL, HTL and LBL epitopes. The efficiency of the construct in binding to some immune receptors and an RBD-potent neutralizing monoclonal antibody (bebtelovimab) was predicted, and its immunogenicity was simulated. Finally, in silico cloning of the constructed gene was performed. The potency of our construct as a SARS-CoV-2 vaccine was validated using several bioinformatics tools. The simulation results showed that the construct can induce both cellular and humoral immune responses by producing appropriate cytokines, and it can even create an excellent immune memory response. Furthermore, the designed construct interacts with innate immune receptors such as TLR2 and TLR4 and the terminal variable domain of bebtelovimab with high affinity. We developed a multi-epitope construct based on the S and M proteins of the SARS-CoV-2 virus with high immunogenicity potential using the most up-to-date immunoinformatics and computational biology approaches. The actual efficiency of this multi-epitope vaccine should be further evaluated via in vitro and in vivo studies.Communicated by Ramaswamy H. Sarma.
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Enzyme therapy for celiac disease (CeD), which digests gliadin into non-immunogenic and non-toxic peptides, can be an appropriate treatment option for CeD. Here, we have investigated the effectiveness of bromelain and ficin on gliadin digestion using in vitro, such as SDS-PAGE, HPLC, and circular dichroism (CD). Furthermore, the cytotoxicity of gliadin and 19-mer peptide before and after digestion with these enzymes was evaluated using the MTT assay in the Caco-2 cell line. Finally, we examined the effect of these treatments along with Larazotide Acetate on the expression of genes involved in cell-tight junctions, such as Occludin, Claudin 3, tight junction protein-1, and Zonulin in the Caco-2 cell line. Our study demonstrated bromelain and ficin digestion effects on the commercial and wheat-extracted gliadin by SDS-PAGE, HPLC, and CD. Also, the cytotoxicity results on Caco-2 showed that toxicity of the gliadin and synthetic 19-mer peptide was decreased by adding bromelain and ficin. Furthermore, the proteolytic effects of bromelain and ficin on gliadin indicated the expression of genes involved in cell-tight junctions was improved. This study confirms that bromelain and ficin mixture could be effective in improving the symptoms of CeD.
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Doença Celíaca , Gliadina , Humanos , Células CACO-2 , Gliadina/farmacologia , Gliadina/metabolismo , Junções Íntimas , Ficina , Bromelaínas/farmacologia , Peptídeos/farmacologiaRESUMO
Co-infection of COVID-19 with other diseases increases the challenges related to its treatment management. COVID-19 co-infection with parasites is studied with low frequency. Here, we systematically reviewed the cases of parasitic disease co-infection with COVID-19. All articles on COVID-19 co-infected with parasites (protozoa, helminths, and ectoparasites), were screened through defined inclusion/exclusion criteria. Of 2190 records, 35 studies remained for data extraction. The majority of studies were about COVID-19 co-infected with malaria, followed by strongyloidiasis, amoebiasis, chagas, filariasis, giardiasis, leishmaniasis, lophomoniasis, myiasis, and toxoplasmosis. No or low manifestation differences were reported between the co-infected cases and naïve COVID-19 or naïve parasitic disease. Although there was a relatively low number of reports on parasitic diseases-COVID-19 co-infection, COVID-19 and some parasitic diseases have overlapping symptoms and also COVID-19 conditions and treatment regimens may cause some parasites re-emergence, relapse, or re-activation. Therefore, more attention should be paid to the on-time diagnosis of COVID-19 and the co-infected parasites.
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In a significant percentage of breast cancers, increased expression of the HER2 receptor is seen and is associated with the spread and worsening of the disease. This research aims to investigate the effect of miR-559 (which targets HER2 mRNA) on SKBR3 breast cancer cells and the possibility of their effective delivery with polymeric nanoparticles and tumor-targeting peptides. L-DOPA monomers were polymerized on the surface of silica nanoparticles in the presence of miR-559 (as a molecular template for molecular imprinting) then an anti-HER2 peptide coupled to the surface of these polymeric nanocomposites (miR-NC-NL2), and the effects of this construct against a HER2-positive breast cancer cells (SKBR3 cells) investigated in vitro conditions. The results showed that miR-NC-NL2 is selective for HER2-positive cells and delivers the miR-559 to them in a targeted manner. miR-NC-NL2 decreased the proliferation of SKBR3 cells and reduced the expression and production of HER2 protein in these cells. Effective and targeted delivery of miR-559 to HER2-positive cancer cells by the miR-NC-NL2 promises the therapeutic potential of this nascent structure based on its inhibitory effect on cancer growth and progression. Of course, animal experiments require a better understanding of this structure's anti-tumor effects.
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MicroRNAs , Impressão Molecular , Neoplasias , Animais , Levodopa/farmacologia , Dióxido de Silício , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Proliferação de Células , Linhagem Celular Tumoral , Fragmentos de Peptídeos/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismoRESUMO
BACKGROUND: Streptococcus pneumoniae (Pneumococcus) has remained a leading cause of fatal infections such as pneumonia, meningitis, and sepsis. Moreover, this pathogen plays a major role in bacterial co-infection in patients with life-threatening respiratory virus diseases such as influenza and COVID-19. High morbidity and mortality in over one million cases, especially in very young children and the elderly, are the main motivations for pneumococcal vaccine development. Due to the limitations of the currently marketed polysaccharide-based vaccines, non-serotype-specific protein-based vaccines have received wide research interest in recent years. One step further is to identify high antigenic regions within multiple highly-conserved proteins in order to develop peptide vaccines that can affect various stages of pneumococcal infection, providing broader serotype coverage and more effective protection. In this study, immunoinformatics tools were used to design an effective multi-epitope vaccine in order to elicit neutralizing antibodies against multiple strains of pneumococcus. RESULTS: The B- and T-cell epitopes from highly protective antigens PspA (clades 1-5) and PhtD were predicted and immunodominant peptides were linked to each other with proper linkers. The domain 4 of Ply, as a potential TLR4 agonist adjuvant candidate, was attached to the end of the construct to enhance the immunogenicity of the epitope vaccine. The evaluation of the physicochemical and immunological properties showed that the final construct was stable, soluble, antigenic, and non-allergenic. Furthermore, the protein was found to be acidic and hydrophilic in nature. The protein 3D-structure was built and refined, and the Ramachandran plot, ProSA-web, ERRAT, and Verify3D validated the quality of the final model. Molecular docking analysis showed that the designed construct via Ply domain 4 had a strong interaction with TLR4. The structural stability of the docked complex was confirmed by molecular dynamics. Finally, codon optimization was performed for gene expression in E. coli, followed by in silico cloning in the pET28a(+) vector. CONCLUSION: The computational analysis of the construct showed acceptable results, however, the suggested vaccine needs to be experimentally verified in laboratory to ensure its safety and immunogenicity.
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COVID-19 , Streptococcus pneumoniae , Criança , Humanos , Pré-Escolar , Idoso , Simulação de Acoplamento Molecular , Escherichia coli , Receptor 4 Toll-Like , Epitopos de Linfócito T/química , Vacinas de Subunidades Antigênicas/química , Vacinas de Subunidades Antigênicas/genética , Epitopos de Linfócito B , Biologia Computacional/métodosRESUMO
In spite of existing cases of severe viral infections with a high mortality rate, there are not enough antiviral drugs and vaccines available for the prevention and treatment of such diseases. In addition, the increasing reports of the emergence of viral epidemics highlight, the need for novel molecules with antiviral potential. Antimicrobial peptides (AMPs) with antiviral activity or antiviral peptides (AVPs) have turned into a research hotspot and already show tremendous potential to become pharmaceutically available antiviral medicines. AMPs, a diverse group of bioactive peptides act as a part of our first line of defense against pathogen inactivation. Although most of the currently reported AMPs are either antibacterial or antifungal peptides, the number of antiviral peptides is gradually increasing. Some of the AMPs that are shown as effective antivirals have been deployed against viruses such as influenza A virus, severe acute respiratory syndrome coronavirus (SARS-CoV), HIV, HSV, West Nile Virus (WNV), and other viruses. This review offers an overview of AVPs that have been approved within the past few years and will set out a few of the most essential patents and their usage within the context mentioned above during 2000-2020. Moreover, the present study will explain some of the progress in antiviral drugs based on peptides and peptide-related antivirals.
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BACKGROUND: With the emergence of drug-resistant fungi and the increased population prone to fungal infections, more effective antifungal drugs are needed. Aurein 1.2 is a potent antimicrobial peptide. Here, we designed a novel derivative of Aurein 1.2, called Aurein N3, which is a modified form of Aurein N2 (another Aurein 1.2 derivative), in which Lys 8 residue was replaced with Leu 13, and was also modified by creating two other mutations. METHODS: Aurein N3 was designed using several algorithms and docking studies. All peptides were synthesized and some of their bio-activity indices such as antifungal properties on 11 fungi, cytotoxicity, hemolysis, and time of the killing were investigated. Electron microscopy, lived/dead staining, and ergosterol binding assay were performed to study their mechanism of action. RESULTS: In comparison to Aurein 1.2 and N2, the docking studies showed that Aurein N3 has reduced binding energy toward ergosterol. The antifungal assessments showed that both Aurein N2 and N3 had strong activity against many fungi. Aurein N3 had lower cytotoxicity and higher binding capability to ergosterol. The hemolytic activity of Aurein N2 and N3 was less than parental Aurein 1.2. All peptides were able to attack the cell wall/membrane and enter the fungi cells. CONCLUSION: Here we introduced a novel derivative of Aurein 1.2 which has lower cytotoxicity, higher ergosterol-binding capability, and comparable antifungal activity compared to the original peptides. It can bind to ergosterol and can also attack the cell wall/membrane of fungi, although more studies are required to find its accurate mechanism of action.
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Antifúngicos , Peptídeos Catiônicos Antimicrobianos , Antifúngicos/química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Membrana Celular , Ergosterol/metabolismo , Fungos/metabolismo , Hemólise , Testes de Sensibilidade MicrobianaRESUMO
During pregnancy, the immune responses are modulated to protect mothers and infants from different pathogens. Cathelicidin as an antimicrobial peptide has a defending role against many pathogens. In this study, to better understand the role of cathelicidin peptide and three of its related proteins in immune pathways (ERK, MyD88, and TLR-9) in the immune system during pregnancy, we examined their expression in the blood of non-pregnant and pregnant mothers and their infant's cord blood. Blood samples were taken, and their peripheral blood mononuclear cells (PBMCs) were obtained. The expression level of cathelicidin was determined by quantitative PCR. Also, the expression of cathelicidin, ERK, MyD88, and TLR-9 was assessed by Western blotting. Higher level of cathelicidin mRNA was detected in the cord blood samples compared to other samples. The Western blotting results showed higher levels of cathelicidin, ERK, MyD88, and TLR-9 in the cord blood samples than in the blood of both pregnant and non-pregnant samples. Also, the level of all molecules was higher in pregnant than non-pregnant women. These high levels of the mentioned molecules are necessary to protect the mother and fetus against various pathogens, although understanding their mechanism of action needs more studies.
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Sangue Fetal , Fator 88 de Diferenciação Mieloide , Feminino , Humanos , Lactente , Gravidez , Leucócitos Mononucleares/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/análise , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor Toll-Like 9/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , CatelicidinasRESUMO
BACKGROUND: Streptococcus pneumoniae is the leading reason for invasive diseases including pneumonia and meningitis, and also secondary infections following viral respiratory diseases such as flu and COVID-19. Currently, serotype-dependent vaccines, which have several insufficiency and limitations, are the only way to prevent pneumococcal infections. Hence, it is plain to need an alternative effective strategy for prevention of this organism. Protein-based vaccine involving conserved pneumococcal protein antigens with different roles in virulence could provide an eligible alternative to existing vaccines. METHODS: In this study, PspC, PhtD and PsaA antigens from pneumococcus were taken to account to predict B-cell and helper T-cell epitopes, and epitope-rich regions were chosen to build the construct. To enhance the immunogenicity of the epitope-based vaccine, a truncated N-terminal fragment of pneumococcal endopeptidase O (PepO) was used as a potential TLR2/4 agonist which was identified by molecular docking studies. The ultimate construct was consisted of the chosen epitope-rich regions, along with the adjuvant role (truncated N-PepO) and suitable linkers. RESULTS: The epitope-based vaccine was assessed as regards physicochemical properties, allergenicity, antigenicity, and toxicity. The 3D structure of the engineered construct was modeled, refined, and validated. Molecular docking and simulation of molecular dynamics (MD) indicated the proper and stable interactions between the vaccine and TLR2/4 throughout the simulation periods. CONCLUSIONS: For the first time this work presents a novel vaccine consisting of epitopes of PspC, PhtD, and PsaA antigens which is adjuvanted with a new truncated domain of PepO. The computational outcomes revealed that the suggested vaccine could be deemed an efficient therapeutic vaccine for S. pneumoniae; nevertheless, in vitro and in vivo examinations should be performed to prove the potency of the candidate vaccine.
Assuntos
COVID-19 , Streptococcus pneumoniae , Adjuvantes Imunológicos , Antígenos de Bactérias , Proteínas de Bactérias , Biologia Computacional , Epitopos de Linfócito B/química , Epitopos de Linfócito T/química , Humanos , Metaloendopeptidases , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Receptor 2 Toll-Like , Vacinas de Subunidades Antigênicas/químicaRESUMO
In this study, a novel nanobiocomposite was synthesized using graphene oxide, lignin, silk fibroin and ZnO and used in biological fields. To synthesize this structure, after preparing graphene oxide by the Hummer method, lignin, silk fibroin, and ZnO nanoparticles (NPs) were added to it, respectively. Also, ZnO NPs with a particle size of about 18 nm to 33 nm was synthesized via Camellia sinensis extract by green methodology. The synthesized structure was examined as anti-biofilm agent and it was observed that the Graphene oxide-lignin/silk fibroin/ZnO nanobiocomposite has a significant ability to prevent the formation of P. aeruginosa biofilm. In addition, due to the importance of the possibility of using this structure in biological environments, its toxicity and blood compatibility were also evaluated. According to the obtained results from MTT assay, the viability percentages of Hu02 cells treated with Graphene oxide-lignin/silk fibroin/ZnO nanobiocomposite after 24, 48, and 72 h of incubation were 89.96%, 89.32%, and 91.28%. On the other hand, the hemolysis percentage of the synthesized structure after 24 h and 72 h of extraction was 9.5% and 11.76% respectively. As a result, the synthesized structure has a hemolysis percentage below 12% and its toxicity effect on Hu02 cells is below 9%.
Assuntos
Fibroínas , Nanopartículas Metálicas , Óxido de Zinco , Antibacterianos/química , Fibroínas/química , Grafite , Hemólise , Humanos , Lignina , Pseudomonas aeruginosa , Óxido de Zinco/farmacologiaRESUMO
In this paper, a novel graphene oxide-folic acid/silk fibroin (GO-FA/SF) nanobiocomposite scaffold was designed and fabricated using affordable and non-toxic materials. The GO was synthesized using the hummer method, covalently functionalized with FA, and then easily conjugated with extracted SF via the freeze-drying process. For characterization of the scaffold, several techniques were employed: Fourier-transform infrared (FT-IR), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), and thermogravimetric analysis (TGA). The cell viability method, hemolysis, and anti-biofilm assays were performed, exploring the biological capability of the nanobiocomposite. The cell viability percentages were 96.67, 96.35 and 97.23% for 24, 48, and 72 h, respectively, and its hemolytic effect was less than 10%. In addition, it was shown that this nanobiocomposite prevents the formation of Pseudomonas aeruginosa biofilm and has antibacterial activity.