RESUMO
Helminth-derived proteins have immunomodulatory properties, influencing the host's immune response as an adaptive strategy for helminth survival. Helminth-derived proteins modulate the immune response by inducing anti-inflammatory cytokines, promoting regulatory T-cell development, and ultimately favouring a Th2-biased immune response. This systematic review focused on helminth-derived proteins and explored their impact on reducing inflammatory responses in mouse models of colitis. A systematic search across Medline, EMBASE, Web of Science, and Cochrane Library identified fourteen relevant studies. These studies reported immunomodulatory changes, including increased production of anti-inflammatory cells and cytokines. In mouse models of colitis treated with on helminth-derived proteins, significant improvements in pathological parameters such as body weight, colon length, and microscopic inflammatory scores were observed compared to control groups. Moreover, helminth-derived proteins can enhance the function of Tregs and alleviate the severity of inflammatory conditions. The findings underscore the pivotal role of helminth-derived proteins in immunomodulation, specifically in the axis of cytokine secretion and immune cell polarization. The findings offer new opportunities for treating chronic inflammatory conditions such Crohn's disease.
Assuntos
Colite , Proteínas de Helminto , Animais , Camundongos , Colite/terapia , Citocinas/metabolismo , Modelos Animais de Doenças , Proteínas de Helminto/uso terapêutico , Helmintos , Sistema Imunitário/metabolismo , Fatores ImunológicosRESUMO
BACKGROUND: The Middle East respiratory syndrome coronavirus (MERS-CoV) is a highly pathogenic zoonotic betacoronavirus and a global public health concern. Better undersetting of the immune responses to MERS-CoV is needed to characterize the correlates of protection and durability of the immunity and to aid in developing preventative and therapeutic interventions. Although MERS-CoV-specific circulating antibodies could persist for several years post-recovery, their waning raises concerns about their durability and role in protection. Nonetheless, memory B and T cells could provide long-lasting protective immunity despite the serum antibodies levels. METHODS: Serological and flow cytometric analysis of MERS-CoV-specific immune responses were performed on samples collected from a cohort of recovered individuals who required intensive care unit (ICU) admission as well as hospital or home isolation several years after infection to characterize the longevity and quality of humoral and cellular immune responses. RESULTS: Our data showed that MERS-CoV infection could elicit robust long-lasting virus-specific binding and neutralizing antibodies as well as T- and B-cell responses up to 6.9 years postinfection regardless of disease severity or need for ICU admission. Apart from the persistent high antibody titers, this response was characterized by B-cell subsets with antibody-independent functions as demonstrated by their ability to produce tumor necrosis factor α (TNF-α), interleukin (IL)-6, and interferon γ (IFN-γ) cytokines in response to antigen stimulation. Furthermore, virus-specific activation of memory CD8+ and CD4+ T cell subsets from MERS-recovered patients resulted in secretion of high levels of TNF-α, IL-17, and IFN-γ. CONCLUSIONS: MERS-CoV infection could elicit robust long-lasting virus-specific humoral and cellular responses.
Assuntos
Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , Infecções por Coronavirus/prevenção & controle , Imunidade Celular , Interferon gama , Fator de Necrose Tumoral alfa , Linfócitos T/imunologia , Linfócitos B/imunologiaRESUMO
Considering the global trend to confine the COVID-19 pandemic by applying various preventive health measures, preprocedural mouth rinsing has been proposed to mitigate the transmission risk of SARS-CoV-2 in dental clinics. The study aimed to investigate the effect of different mouth rinses on salivary viral load in COVID-19 patients. This study was a single-center, randomized, double-blind, six-parallel-group, placebo-controlled clinical trial that investigated the effect of four mouth rinses (1% povidone-iodine, 1.5% hydrogen peroxide, 0.075% cetylpyridinium chloride, and 80 ppm hypochlorous acid) on salivary SARS-CoV-2 viral load relative to the distilled water and no-rinse control groups. The viral load was measured by quantitative reverse transcription PCR (RT-qPCR) at baseline and 5, 30, and 60 min post rinsing. The viral load pattern within each mouth rinse group showed a reduction overtime; however, this reduction was only statistically significant in the hydrogen peroxide group. Further, a significant reduction in the viral load was observed between povidone-iodine, hydrogen peroxide, and cetylpyridinium chloride compared to the no-rinse group at 60 min, indicating their late antiviral potential. Interestingly, a similar statistically significant reduction was also observed in the distilled water control group compared to the no-rinse group at 60 min, proposing mechanical washing of the viral particles through the rinsing procedure. Therefore, results suggest using preprocedural mouth rinses, particularly hydrogen peroxide, as a risk-mitigation step before dental procedures, along with strict adherence to other infection control measures.
Assuntos
COVID-19 , Antissépticos Bucais , Humanos , Antissépticos Bucais/uso terapêutico , SARS-CoV-2 , Peróxido de Hidrogênio , Povidona-Iodo/uso terapêutico , Cetilpiridínio/uso terapêutico , Pandemias , Carga Viral , ÁguaRESUMO
BACKGROUND: Livelihood activities and human movements participate in the epidemiology of vector-borne diseases and influence malaria risk in elimination settings. In Saudi Arabia, where malaria transmission intensity varies geographically, it is vital to understand the components driving transmission within specific areas. In addition, shared social, behavioural, and occupational characteristics within communities may provoke the risk of malaria infection. This study aims to understand the relationship between human mobility, livelihood activities, and the risk of malaria infection in the border region of Jazan to facilitate further strategic malaria interventions. In addition, the study will complement and reinforce the existing efforts to eliminate malaria on the Saudi and Yemen border by providing a deeper understanding of human movement and livelihood activities. METHODS: An unmatched case-control study was conducted. A total of 261 participants were recruited for the study, including 81 cases of confirmed malaria through rapid diagnostic tests (RDTs) and microscopy and 180 controls in the Baish Governorate in Jazan Provinces, Saudi Arabia. Individuals who received malaria tests were interviewed regarding their livelihood activities and recent movement (travel history). A questionnaire was administered, and the data was captured electronically. STATA software version 16 was used to analyse the data. Bivariate and multivariate analyses were conducted to determine if engaging in agricultural activities such as farming and animal husbandry, recent travel history outside of the home village within the last 30 days and participating in spiritual gatherings were related to malaria infection status. RESULTS: A logistical regression model was used to investigate components associated with malaria infection. After adjusting several confounding factors, individuals who reported travelling away from their home village in the last 30 days OR 11.5 (95% CI 4.43-29.9), and those who attended a seasonal night spiritual gathering OR 3.04 (95% CI 1.10-8.42), involved in animal husbandry OR 2.52 (95% CI 1.10-5.82), and identified as male OR 4.57 (95% CI 1.43-14.7), were more likely to test positive for malaria infection. CONCLUSION: Human movement and livelihood activities, especially at nighttime, should be considered malaria risk factors in malaria elimination settings, mainly when the targeted area is limited to a confined borderland area.
Assuntos
Malária , Animais , Humanos , Masculino , Estudos de Casos e Controles , Malária/prevenção & controle , Fatores de Risco , Viagem , Criação de Animais DomésticosRESUMO
Extracellular vehicles (EVs) are nanoscale lipid bilayer vesicles that carry biologically active biomolecule cargos like proteins, lipids, and nucleic acids (DNA, RNA) outside of the cell. Blood (serum/plasma), urine, and bronchoalveolar lavage fluid are all examples of biofluids from which they may be collected. EVs play a vital role in intracellular communication. The molecular signature of EVs largely depends on the parental cell's status. EVs are classified into two groups, (1) exosomes (originated by endogenous route) and (2) microvesicles (originated from the plasma membrane, also known as ectosomes). The quantity and types of EV cargo vary during normal conditions compared to pathological conditions (chronic inflammatory lung diseases or lung cancer). Consequently, EVs contain novel biomarkers that differ based on the cell type of origin and during lung diseases. Small RNAs (e.g., microRNAs) are transported by EVs, which is one of the most rapidly evolving research areas in the field of EVs biology. EV-mediated cargos transport small RNAs that can result in reprograming the target/recipient cells. Multiple chronic inflammatory lung illnesses, such as chronic obstructive pulmonary disease, asthma, pulmonary hypertension, pulmonary fibrosis, cystic fibrosis, acute lung injury, and lung cancer, have been demonstrated to be regulated by EV. In this review, we will consolidate the current knowledge and literature on the novel role of EVs and their small RNAs concerning chronic lung diseases (CLDs). Additionally, we will also provide better insight into the clinical and translational impact of mesenchymal stem cells-derived EVs as novel therapeutic agents in treating CLDs.
Assuntos
Exossomos , Vesículas Extracelulares , Pneumopatias , Neoplasias Pulmonares , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Exossomos/genética , Exossomos/metabolismo , Pneumopatias/genética , Neoplasias Pulmonares/metabolismoRESUMO
The current Coronavirus disease 2019 or COVID-19 pandemic has infected over two million people and resulted in the death of over one hundred thousand people at the time of writing this review. The disease is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Even though multiple vaccines and treatments are under development so far, the disease is only slowing down under extreme social distancing measures that are difficult to maintain. SARS-COV-2 is an enveloped virus that is surrounded by a lipid bilayer. Lipids are fundamental cell components that play various biological roles ranging from being a structural building block to a signaling molecule as well as a central energy store. The role lipids play in viral infection involves the fusion of the viral membrane to the host cell, viral replication, and viral endocytosis and exocytosis. Since lipids play a crucial function in the viral life cycle, we asked whether drugs targeting lipid metabolism, such as statins, can be utilized against SARS-CoV-2 and other viruses. In this review, we discuss the role of lipid metabolism in viral infection as well as the possibility of targeting lipid metabolism to interfere with the viral life cycle.
Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus/metabolismo , Metabolismo dos Lipídeos , Pneumonia Viral/metabolismo , Animais , Vias Biossintéticas , COVID-19 , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Endocitose/efeitos dos fármacos , Humanos , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , SARS-CoV-2 , Internalização do Vírus/efeitos dos fármacosRESUMO
BACKGROUND: Infection control measures have played a major role in limiting human/camel-to-human transmission of Middle East respiratory syndrome coronavirus (MERS-CoV); however, development of effective and safe human or camel vaccines is warranted. METHODS: We extended and optimized our previous recombinant adenovirus 5 (rAd5)-based vaccine platform characterized by in vivo amplified and CD40-mediated specific responses to generate MERS-CoV S1 subunit-based vaccine. We generated rAd5 constructs expressing CD40-targeted S1 fusion protein (rAd5-S1/F/CD40L), untargeted S1 (rAd5-S1), and Green Fluorescent Protein (rAd5-GFP), and evaluated their efficacy and safety in human dipeptidyl peptidase 4 transgenic (hDPP4 Tg+) mice. RESULTS: Immunization of hDPP4 Tg+ mice with a single dose of rAd5-S1/F/CD40L elicited as robust and significant specific immunoglobulin G and neutralizing antibodies as those induced with 2 doses of rAd5-S1. After MERS-CoV challenge, both vaccines conferred complete protection against morbidity and mortality, as evidenced by significantly undetectable/reduced pulmonary viral loads compared to the control group. However, rAd5-S1- but not rAd5-S1/F/CD40L-immunized mice exhibited marked pulmonary perivascular hemorrhage post-MERS-CoV challenge despite the observed protection. CONCLUSIONS: Incorporation of CD40L into rAd5-based MERS-CoV S1 vaccine targeting molecule and molecular adjuvants not only enhances immunogenicity and efficacy but also prevents inadvertent pulmonary pathology after viral challenge, thereby offering a promising strategy to enhance safety and potency of vaccines.
Assuntos
Ligante de CD40/farmacologia , Infecções por Coronavirus/prevenção & controle , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Adenovírus Humanos/genética , Adjuvantes Imunológicos/genética , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Ligante de CD40/genética , Infecções por Coronavirus/imunologia , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Portadores de Fármacos , Vetores Genéticos , Imunoglobulina G/sangue , Pulmão/virologia , Camundongos , Camundongos Transgênicos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/farmacologia , Glicoproteína da Espícula de Coronavírus/genética , Análise de Sobrevida , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Carga Viral , Vacinas Virais/administração & dosagem , Vacinas Virais/genéticaRESUMO
More than two million Muslims visit Makkah, Saudi Arabia, annually to perform the religious rituals of Hajj where the risk of spreading respiratory infections is very common. The aim here was to screen symptomatic pilgrims for Middle East respiratory syndrome coronavirus (MERS-CoV) and other viral etiologies. Thus, 132 nasopharyngeal samples were collected from pilgrims presenting with acute respiratory symptoms at the healthcare facilities in the holy sites during the 5 days of the 2014 Hajj season. Samples were tested using real-time reverse transcription polymerase chain reactions and microarray. Demographic data including age, sex, and country of origin were obtained for all participants. While we did not detect MERS-CoV in any of the samples, several other viruses were detected in 50.8% of the cases. Among the detected viruses, 64.2% of the cases were due to a single-virus infection and 35.8% were due to the coinfections with up to four viruses. The most common respiratory virus was influenza A, followed by non-MERS human coronaviruses, rhinoviruses, and influenza B. Together, we found that it was not MERS-CoV but other respiratory viruses that caused acute respiratory symptoms among pilgrims. The observed high prevalence of influenza viruses underscores the need for more effective surveillance during the Hajj and adoption of stringent vaccination requirements from all pilgrims.
Assuntos
Infecções por Coronavirus/virologia , Influenza Humana/virologia , Islamismo , Infecções Respiratórias/virologia , Viagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Coinfecção/epidemiologia , Coinfecção/virologia , Coronavirus/isolamento & purificação , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Nasofaringe/virologia , Orthomyxoviridae/isolamento & purificação , Prevalência , Infecções Respiratórias/epidemiologia , Rhinovirus/isolamento & purificação , Arábia Saudita/epidemiologia , Estações do Ano , Adulto JovemRESUMO
BACKGROUND: Middle East respiratory syndrome-coronavirus (MERS-CoV) is a novel zoonotic pathogen. Although the potential for MERS-CoV transmission through blood transfusion is not clear, MERS-CoV was recognized as a pathogen of concern for the safety of the blood supply especially after its detection in whole blood, serum, and plasma of infected individuals. Here we investigated the efficacy of amotosalen and ultraviolet A light (UVA) to inactivate MERS-CoV in fresh-frozen plasma (FFP). STUDY DESIGN AND METHODS: Pooled FFP units were spiked with a recent clinical MERS-CoV isolate. Infectious and genomic viral titers were determined in plasma before and after inactivation with amotosalen/UVA treatment by plaque assay and reverse transcription-quantitative polymerase chain reaction, respectively. In addition, residual replicating or live virus after inactivation was examined by passaging in the permissive Vero E6 cells. RESULTS: The mean MERS-CoV infectious titer in pretreatment samples was 4.67 ± 0.25 log plaque-forming units (pfu)/mL, which was reduced to undetectable levels after inactivation with amotosalen/UVA demonstrating a mean log reduction of more than 4.67 ± 0.25 pfu/mL. Furthermore, inoculation of inactivated plasma on Vero E6 cells did not result in any cytopathic effect (CPE) even after 7 days of incubation and three consecutive passages, nor the detection of MERS RNA compared to pretreatment samples which showed complete CPE within 2 to 3 days postinoculation and log viral RNA titer ranging from 9.48 to 10.22 copies/mL in all three passages. CONCLUSION: Our data show that amotosalen/UVA treatment is a potent and effective way to inactivate MERS-CoV infectious particles in FFP to undetectable levels and to minimize the risk of any possible transfusion-related MERS-CoV transmission.
Assuntos
Furocumarinas/farmacologia , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Plasma/virologia , Raios Ultravioleta , Inativação de Vírus , Animais , Chlorocebus aethiops , Efeito Citopatogênico Viral , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/crescimento & desenvolvimento , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos da radiação , RNA Viral/sangue , Reação em Cadeia da Polimerase em Tempo Real , Células Vero , Carga Viral/efeitos dos fármacos , Carga Viral/efeitos da radiação , Ensaio de Placa Viral , Replicação Viral/efeitos dos fármacos , Replicação Viral/efeitos da radiaçãoRESUMO
The emerged influenza A/H1N1pdm09 viruses have replaced the previously circulating seasonal H1N1 viruses. The close antigenic properties of these viruses to the 1918 H1N1 pandemic viruses and their post-pandemic evolution pattern could further enhance their adaptation and pathogenicity in humans representing a major public health threat. Given that data on the dynamics and evolution of these viruses in Saudi Arabia is sparse we investigated the genetic diversity of circulating influenza A/H1N1pdm09 viruses from Jeddah, Saudi Arabia, by analyzing 39 full genomes from isolates obtained between 2014-2015, from patients with varying symptoms. Phylogenetic analysis of all gene segments and concatenated genomes showed similar topologies and co-circulation of clades 6b, 6b.1 and 6b.2, with clade 6b.1 being the most predominate since 2015. Most viruses were more closely related to the vaccine strain (Michigan/45/2015) recommended for the 2017/2018 season, than to the California/07/2009 strain. Low sequence variability was observed in the haemagglutinin protein compared to the neuraminidase protein. Resistance to neuraminidase inhibitors was limited as only one isolate had the H275Y substitution. Interestingly, two isolates had short PA-X proteins of 206 amino acids compared to the 232 amino acid protein found in most influenza A/H1N1pdm09 viruses. Together, the co-circulation of several clades and the predominance of clade 6b.1, despite its low circulation in Asia in 2015, suggests multiple introductions most probably during the mass gathering events of Hajj and Umrah. Jeddah represents the main port of entry to the holy cities of Makkah and Al-Madinah, emphasizing the need for vigilant surveillance in the kingdom.
Assuntos
Variação Genética , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/virologia , Substituição de Aminoácidos , Feminino , Genoma Viral , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/transmissão , Masculino , Nasofaringe/virologia , Neuraminidase/genética , Filogenia , RNA Viral/genética , Arábia Saudita/epidemiologia , Estações do Ano , Análise de Sequência de DNA , Proteínas Virais/genéticaRESUMO
We describe the isolation and sequencing of Middle East respiratory syndrome coronavirus (MERS-CoV) obtained from a dromedary camel and from a patient who died of laboratory-confirmed MERS-CoV infection after close contact with camels that had rhinorrhea. Nasal swabs collected from the patient and from one of his nine camels were positive for MERS-CoV RNA. In addition, MERS-CoV was isolated from the patient and the camel. The full genome sequences of the two isolates were identical. Serologic data indicated that MERS-CoV was circulating in the camels but not in the patient before the human infection occurred. These data suggest that this fatal case of human MERS-CoV infection was transmitted through close contact with an infected camel.
Assuntos
Camelus/virologia , Infecções por Coronavirus/transmissão , Coronavirus/isolamento & purificação , Nariz/virologia , Adulto , Animais , Coronavirus/genética , Genoma Viral , Humanos , Masculino , Oriente Médio , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Arábia Saudita , Zoonoses/transmissãoRESUMO
Flaviviruses represent a global public health concern. They consist of â¼70 viruses with almost half of them causing human diseases with unspecified febrile illnesses. Cities in western Saudi Arabia are endemic for viruses (DENV) with sporadic infections due to Alkhumra hemorrhagic fever virus (AHFV). They also represent a major destination for travelers coming for annual religious pilgrimages (Hajj and Umrah) from all over the world. However, whether other flaviviruses are circulating is not known because of the limited number of surveillance studies. Here, we retrospectively screened 690 samples for flaviviruses in samples from patients with unexplained febrile illnesses between 2010 and 2015 in western Saudi Arabia using a pan-flaviviruses RT-PCR assay. Despite Zika virus RNA was not detected, this study confirms circulation and/or sporadic spread of DENV-2, DENV-3, and AHFV, higher prevalence of DENV-2, and a role for visitors from DENV endemic countries in DENV importation into the Kingdom. Further analysis also showed very low genetic diversity of AHFV confirming its slow microevolution. Accordingly, continuous and prospective surveillance for flaviviruses using such assay are warranted in Saudi Arabia which receives millions of Muslims annually to implement effective control measures in light of the global widespread and outbreaks of several flaviviruses.
Assuntos
Vírus da Dengue/isolamento & purificação , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Febre/epidemiologia , Febre/etiologia , Filogenia , Zika virus/isolamento & purificação , Vírus da Dengue/classificação , Vírus da Dengue/genética , Vírus da Encefalite Transmitidos por Carrapatos/classificação , Vírus da Encefalite Transmitidos por Carrapatos/genética , Variação Genética , Genótipo , Humanos , Prevalência , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Arábia Saudita/epidemiologia , Zika virus/classificação , Zika virus/genéticaRESUMO
CD40L, a key regulator of the immune system, was studied as both a targeting ligand and a molecular adjuvant in nucleoprotein (NP)-based host defense against influenza in mouse models with different genetic backgrounds. Adenoviral vectors secreting NP-CD40L fusion protein (denoted as rAd-SNP40L) afforded full protection of immunocompetent and immunocompromised mice (CD40L(-/-) and CD4(-/-)) against lethal influenza infection. Mechanistically, rAd-SNP40L preferentially induced early and persistent B cell germinal center formation, and accelerated Ig isotype-switching and Th1-skewed, NP-specific Ab response. Moreover, it drastically augmented primary and memory NP-specific CTL activity and polyfunctional CD8(+) T cells. The markedly enhanced nonneutralizing Abs and CTLs significantly reduced viral burdens in the lungs of mice upon lethal virus challenge. Data generated from CD40L(-/-) and CD4(-/-) mice revealed that the protection was indeed CD40L mediated but CD4(+) T cell independent, demonstrating the viability of the fusion Ags in protecting immunodeficient hosts. Notably, a single dose of rAd-SNP40L completely protected mice from lethal viral challenge 4 mo after immunization, representing the first report, to our knowledge, on NP in conjunction with a molecular adjuvant inducing a robust and long-lasting memory immune response against influenza. This platform is characterized by an increased in vivo load of CD40-targeted Ag upon the secretion of the fusion protein from adenovirus-infected cells and may represent a promising strategy to enhance the breadth, durability, and potency of Ag-specific immune responses.
Assuntos
Imunidade Adaptativa/imunologia , Ligante de CD40/imunologia , Vírus da Influenza A/imunologia , Infecções por Orthomyxoviridae/imunologia , Imunidade Adaptativa/genética , Adenoviridae/genética , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Ligante de CD40/deficiência , Ligante de CD40/genética , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Cães , Feminino , Vetores Genéticos/genética , Células HEK293 , Humanos , Imunização , Vírus da Influenza A/fisiologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células NIH 3T3 , Nucleoproteínas/genética , Nucleoproteínas/imunologia , Nucleoproteínas/metabolismo , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/virologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sobrevida , Linfócitos T Citotóxicos/imunologiaRESUMO
BACKGROUND: Dengue viruses (DENVs) are mosquito-borne viruses which can cause disease ranging from mild fever to severe dengue infection. These viruses are endemic in several tropical and subtropical regions. Multiple outbreaks of DENV serotypes 1, 2 and 3 (DENV-1, DENV-2 and DENV-3) have been reported from the western region in Saudi Arabia since 1994. Strains from at least two genotypes of DENV-1 (Asia and America/Africa genotypes) have been circulating in western Saudi Arabia until 2006. However, all previous studies reported from Saudi Arabia were based on partial sequencing data of the envelope (E) gene without any reports of full genome sequences for any DENV serotypes circulating in Saudi Arabia. FINDINGS: Here, we report the isolation and the first complete genome sequence of a DENV-1 strain (DENV-1-Jeddah-1-2011) isolated from a patient from Jeddah, Saudi Arabia in 2011. Whole genome sequence alignment and phylogenetic analysis showed high similarity between DENV-1-Jeddah-1-2011 strain and D1/H/IMTSSA/98/606 isolate (Asian genotype) reported from Djibouti in 1998. Further analysis of the full envelope gene revealed a close relationship between DENV-1-Jeddah-1-2011 strain and isolates reported between 2004-2006 from Jeddah as well as recent isolates from Somalia, suggesting the widespread of the Asian genotype in this region. CONCLUSIONS: These data suggest that strains belonging to the Asian genotype might have been introduced into Saudi Arabia long before 2004 most probably by African pilgrims and continued to circulate in western Saudi Arabia at least until 2011. Most importantly, these results indicate that pilgrims from dengue endemic regions can play an important role in the spread of new DENVs in Saudi Arabia and the rest of the world. Therefore, availability of complete genome sequences would serve as a reference for future epidemiological studies of DENV-1 viruses.
Assuntos
Vírus da Dengue/classificação , Vírus da Dengue/genética , Genoma Viral , RNA Viral/genética , Análise de Sequência de DNA , Adulto , Animais , Dengue/epidemiologia , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/isolamento & purificação , Feminino , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Arábia Saudita/epidemiologia , Homologia de SequênciaRESUMO
The only universally conserved sequence among all influenza A viral neuraminidases is located between amino acids 222 and 230. However, the potential roles of these amino acids remain largely unknown. Through an array of experimental approaches including mutagenesis, reverse genetics, and growth kinetics, we found that this sequence could markedly affect viral replication. Additional experiments revealed that enzymes with mutations in this region demonstrated substantially decreased catalytic activity, substrate binding, and thermostability. Consistent with viral replication analyses and enzymatic studies, protein modeling suggests that these amino acids could either directly bind to the substrate or contribute to the formation of the active site in the enzyme. Collectively, these findings reveal the essential role of this unique region in enzyme function and viral growth, which provides the basis for evaluating the validity of this sequence as a potential target for antiviral intervention and vaccine development.
Assuntos
Epitopos/metabolismo , Vírus da Influenza A/enzimologia , Neuraminidase/metabolismo , Proteínas Virais/metabolismo , Replicação Viral , Substituição de Aminoácidos , Animais , Sítios de Ligação/genética , Biocatálise , Domínio Catalítico , Linhagem Celular , Embrião de Galinha , Estabilidade Enzimática/genética , Epitopos/química , Epitopos/genética , Células HEK293 , Humanos , Vírus da Influenza A/genética , Cinética , Modelos Moleculares , Mutação , Neuraminidase/química , Neuraminidase/genética , Estrutura Terciária de Proteína , Especificidade por Substrato , Temperatura , Proteínas Virais/química , Proteínas Virais/genéticaRESUMO
Background Coronaviruses (CoVs) pose significant health risks to humans, with recent outbreaks like severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) underscoring their zoonotic potential. Dromedary camels (Camelus dromedarius) have been implicated as intermediate hosts for MERS-CoV, prompting heightened surveillance efforts. This study aims to identify non-MERS-CoV CoVs in imported camels at the Jeddah seaport, Saudi Arabia, using molecular techniques. Methods Camel nasal swabs (n = 337) were collected from imported dromedary camels arriving at the Jeddah Islamic seaport from Sudan and Djibouti. Samples were tested for CoVs using real-time real-time reverse transcription polymerase chain reaction (RT-PCR) targeting the RNA-dependent RNA polymerase gene. Positive samples were confirmed by conventional RT-PCR and Sanger sequencing. Selected samples underwent RNA sequencing to identify viral genomes. The study underscores the importance of molecular surveillance in camels to mitigate zoonotic risks. Results Out of 337 camel samples tested, 28 (8.30%) were positive for CoVs, predominantly from camels imported from Djibouti, compared to Sudan (13.39% vs. 5.78%). Sequence analysis confirmed the presence of non-MERS CoVs, including camel alpha-coronavirus and human CoV-229E-related strains. These findings highlight potential viral diversity and transmission risks in imported camel populations. Conclusion This study identifies diverse CoVs circulating in imported dromedary camels at the Jeddah Islamic seaport, Saudi Arabia, underscoring their potential role in zoonotic transmission. Enhanced surveillance and collaborative efforts are essential to mitigate public health risks associated with novel coronavirus strains from camel populations.
RESUMO
Colorectal cancer (CRC) is the third most common cancer globally and presents a significant challenge owing to its high mortality rate and the limitations of traditional treatment options such as surgery, radiotherapy, and chemotherapy. While these treatments are foundational, they are often poorly effective owing to tumor resistance. Immunotherapy is a groundbreaking alternative that has recently emerged and offers new hope for success by exploiting the body's own immune system. This article aims to provide an extensive review of clinical trials evaluating the efficacy of various immunotherapies, including CRC vaccines, chimeric antigen receptor T-cell therapies, and immune checkpoint inhibitors. We also discuss combining CRC vaccines with monoclonal antibodies, delve into preclinical studies of novel cancer vaccines, and assess the impact of these treatment methods on patient outcomes. This review seeks to provide a deeper understanding of the current state of CRC treatment by evaluating innovative treatments and their potential to redefine the prognosis of patients with CRC.
Assuntos
Vacinas Anticâncer , Neoplasias Colorretais , Humanos , Imunoterapia/métodos , Imunoterapia Adotiva , Resultado do TratamentoRESUMO
Epithelial cancer cells rely on the extracellular matrix (ECM) attachment in order to spread to other organs. Detachment from the ECM is necessary for these cells to seed in other locations. When the attachment to the ECM is lost, cellular metabolism undergoes a significant shift from oxidative metabolism to glycolysis. Additionally, the cancer cells become more dependent on glutaminolysis to avoid a specific type of cell death known as anoikis, which is associated with ECM detachment. In our recent study, we observed increased expression of H3K27me3 demethylases, specifically KDM6A/B, in cancer cells that were resistant to anoikis. Since KDM6A/B is known to regulate cellular metabolism, we investigated the effects of suppressing KDM6A/B with GSK-J4 on the metabolic processes in these anoikis-resistant cancer cells. Our results from untargeted metabolomics revealed a profound impact of KDM6A/B inhibition on various metabolic pathways, including glycolysis, methyl histidine, spermine, and glutamate metabolism. Inhibition of KDM6A/B led to elevated reactive oxygen species (ROS) levels and depolarization of mitochondria, while reducing the levels of glutathione, an important antioxidant, by diminishing the intermediates of the glutamate pathway. Glutamate is crucial for maintaining a pool of reduced glutathione. Furthermore, we discovered that KDM6A/B regulates the key glycolytic genes expression like hexokinase, lactate dehydrogenase, and GLUT-1, which are essential for sustaining glycolysis in anoikis-resistant cancer cells. Overall, our findings demonstrated the critical role of KDM6A/B in maintaining glycolysis, glutamate metabolism, and glutathione levels. Inhibition of KDM6A/B disrupts these metabolic processes, leading to increased ROS levels and triggering cell death in anoikis-resistant cancer cells.
RESUMO
BACKGROUND: Middle East Respiratory Syndrome Coronavirus is a highly pathogenic virus that poses a significant threat to public health. OBJECTIVE: The purpose of this study is to develop and characterize novel mouse monoclonal antibodies targeting the spike protein S1 subunit of the Middle East Respiratory Syndrome Corona Virus (MERS-CoV). METHODS: In this study, three mouse monoclonal antibodies (mAbs) against MERS-CoV were generated and characterized using hybridoma technology. The mAbs were evaluated for their reactivity and neutralization activity. The mAbs were generated through hybridoma technology by the fusion of myeloma cells and spleen cells from MERS-CoV-S1 immunized mice. The resulting hybridomas were screened for antibody production using enzyme-linked immunosorbent assays (ELISA). RESULTS: ELISA results demonstrated that all three mAbs exhibited strong reactivity against the MERS-CoV S1-antigen. Similarly, dot-ELISA revealed their ability to specifically recognize viral components, indicating their potential for diagnostic applications. Under non-denaturing conditions, Western blot showed the mAbs to have robust reactivity against a specific band at 116 KDa, corresponding to a putative MERS-CoV S1-antigen. However, no reactive bands were observed under denaturing conditions, suggesting that the antibodies recognize conformational epitopes. The neutralization assay showed no in vitro reactivity against MERS-CoV. CONCLUSION: This study successfully generated three mouse monoclonal antibodies against MERS-CoV using hybridoma technology. The antibodies exhibited strong reactivity against MERS-CoV antigens using ELISA and dot ELISA assays. Taken together, these findings highlight the significance of these mAbs for potential use as valuable tools for MERS-CoV research and diagnosis (community and field-based surveillance and viral antigen detection).
Assuntos
Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Ensaio de Imunoadsorção Enzimática , Hibridomas , Coronavírus da Síndrome Respiratória do Oriente Médio , Glicoproteína da Espícula de Coronavírus , Animais , Glicoproteína da Espícula de Coronavírus/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Anticorpos Monoclonais/imunologia , Camundongos , Anticorpos Antivirais/imunologia , Hibridomas/imunologia , Humanos , Anticorpos Neutralizantes/imunologia , Camundongos Endogâmicos BALB C , Epitopos/imunologia , Testes de Neutralização , Especificidade de Anticorpos/imunologia , Infecções por Coronavirus/imunologia , FemininoRESUMO
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and the Middle East respiratory syndrome coronavirus (MERS-CoV) are highly pathogenic human coronaviruses (CoVs). Anti-CoVs mAbs and vaccines may be effective, but the emergence of neutralization escape variants is inevitable. Angiotensin-converting enzyme 2 and dipeptidyl peptidase 4 enzyme are the getaway receptors for SARS-CoV-2 and MERS-CoV, respectively. Thus, we reformatted these receptors as Fc-fusion decoy receptors. Then, we tested them in parallel with anti-SARS-CoV (ab1-IgG) and anti-MERS-CoV (M336-IgG) mAbs against several variants using pseudovirus neutralization assay. The generated Fc-based decoy receptors exhibited a strong inhibitory effect against all pseudotyped CoVs. Results showed that although mAbs can be effective antiviral drugs, they might rapidly lose their efficacy against highly mutated viruses. We suggest that receptor traps can be engineered as Fc-fusion proteins for highly mutating viruses with known entry receptors, for a faster and effective therapeutic response even against virus harboring antibodies escape mutations.