RESUMEN

Chikungunya fever is a mosquito-borne disease caused by Chikungunya virus (CHIKV). Treatment of CHIKV infections is currently supportive and does not limit viral replication or symptoms of persistent chronic arthritis. Although there are multiple compounds reported as antivirals active against CHIKV in vitro, there are still no effective and safe antivirals. Thus, active research aims at the identification of new chemical structures with antiviral activity. Here, we report the screen of the Pandemic Response Box library of small molecules against a fully infectious CHIKV reporter virus. Our screening approach successfully identified previously reported CHIKV antiviral compounds within this library and further expanded potentially active hits, supporting the use of reporter-virus-based assays in high-throughput screening format as a reliable tool for antiviral drug discovery. Four molecules were identified as potential drug candidates against CHIKV: MMV1634402 (Brilacidin) and MMV102270 (Diphyllin), which were previously shown to present broad-spectrum antiviral activities, in addition to MMV1578574 (Eravacycline), and the antifungal MMV689401 (Fluopicolide), for which their antiviral potential is uncovered here.

Asunto(s)

Antivirales , Fiebre Chikungunya , Virus Chikungunya , Ensayos Analíticos de Alto Rendimiento , Bibliotecas de Moléculas Pequeñas , Virus Chikungunya/efectos de los fármacos , Antivirales/farmacología , Antivirales/química , Fiebre Chikungunya/tratamiento farmacológico , Fiebre Chikungunya/virología , Humanos , Animales , Bibliotecas de Moléculas Pequeñas/farmacología , Ensayos Analíticos de Alto Rendimiento/métodos , Evaluación Preclínica de Medicamentos , Replicación Viral/efectos de los fármacos , Descubrimiento de Drogas , Chlorocebus aethiops , Células Vero

RESUMEN

The current detection method for Chikungunya Virus (CHIKV) involves an invasive and costly molecular biology procedure as the gold standard diagnostic method. Consequently, the search for a non-invasive, more cost-effective, reagent-free, and sustainable method for the detection of CHIKV infection is imperative for public health. The portable Fourier-transform infrared coupled with Attenuated Total Reflection (ATR-FTIR) platform was applied to discriminate systemic diseases using saliva, however, the salivary diagnostic application in viral diseases is less explored. The study aimed to identify unique vibrational modes of salivary infrared profiles to detect CHIKV infection using chemometrics and artificial intelligence algorithms. Thus, we intradermally challenged interferon-gamma gene knockout C57/BL6 mice with CHIKV (20 µl, 1 X 105 PFU/ml, n = 6) or vehicle (20 µl, n = 7). Saliva and serum samples were collected on day 3 (due to the peak of viremia). CHIKV infection was confirmed by Real-time PCR in the serum of CHIKV-infected mice. The best pattern classification showed a sensitivity of 83%, specificity of 86%, and accuracy of 85% using support vector machine (SVM) algorithms. Our results suggest that the salivary ATR-FTIR platform can discriminate CHIKV infection with the potential to be applied as a non-invasive, sustainable, and cost-effective detection tool for this emerging disease.

Asunto(s)

Algoritmos , Inteligencia Artificial , Fiebre Chikungunya , Virus Chikungunya , Saliva , Animales , Saliva/virología , Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/virología , Virus Chikungunya/aislamiento & purificación , Virus Chikungunya/genética , Ratones , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Ratones Endogámicos C57BL , Ratones Noqueados

RESUMEN

Chikungunya virus (CHIKV) is the causative agent of chikungunya fever (CHIKF), and its primary vectors are the mosquitoes Aedes aegypti and Aedes albopictus. CHIKV was initially endemic to Africa but has spread globally in recent years and affected millions of people. According to a risk assessment by the World Health Organization, CHIKV has the potential seriously impact public health. A growing body of research suggests that mutations in the CHIKV gene that enhance viral fitness in the host are contributing to the expansion of the global CHIKF epidemic. In this article, we review the host-adapted gene mutations in CHIKV under natural evolution and laboratory transmission conditions, which can help improve our understanding of the adaptive evolution of CHIKV and provide a basis for monitoring and early warning of future CHIKV outbreaks.

Asunto(s)

Aedes , Fiebre Chikungunya , Virus Chikungunya , Genoma Viral , Mutación , Virus Chikungunya/genética , Fiebre Chikungunya/virología , Fiebre Chikungunya/transmisión , Animales , Humanos , Aedes/virología , Aedes/genética , Mosquitos Vectores/virología , Mosquitos Vectores/genética , Adaptación al Huésped/genética

RESUMEN

BACKGROUND: Many studies have demonstrated the association between intestinal microbiota and joint diseases. The "gut-joint axis" also has potential roles in chikungunya virus (CHIKV) infection. Pro-inflammatory arthritis after CHIKV infection might disrupt host homeostasis and lead to dysbacteriosis. This study investigated the characteristics of fecal and gut microbiota, intestinal metabolites, and the changes in gene regulation of intestinal tissues after CHIKV infection using multi-omics analysis to explore the involvement of gut microbiota in the pathogenesis of CHIKV infection. RESULTS: CHIKV infection increases the systemic burden of inflammation in the GI system of infected animals. Moreover, infection-induced alterations in GI microbiota and metabolites may be indirectly involved in the modulation of GI and bone inflammation after CHIKV infection, including the modulation of inflammasomes and interleukin-17 inflammatory cytokine levels. CONCLUSION: Our results suggest that the GI tract and its microbes are involved in the modulation of CHIKV infection, which could serve as an indicator for the adjuvant treatment of CHIKV infection. Video Abstract.

Asunto(s)

Fiebre Chikungunya , Virus Chikungunya , Heces , Microbioma Gastrointestinal , Macaca mulatta , Animales , Heces/microbiología , Fiebre Chikungunya/virología , Bacterias/clasificación , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Bacterias/genética , Disbiosis/microbiología , Inflamación , Inflamasomas/metabolismo , Modelos Animales de Enfermedad , Interleucina-17/metabolismo , Tracto Gastrointestinal/microbiología , Citocinas/metabolismo

RESUMEN

Chikungunya (CHIKV) and Mayaro (MAYV) viruses are arthritogenic alphaviruses that promote an incapacitating and long-lasting inflammatory muscle-articular disease. Despite studies pointing out the importance of skeletal muscle (SkM) in viral pathogenesis, the long-term consequences on its physiology and the mechanism of persistence of symptoms are still poorly understood. Combining molecular, morphological, nuclear magnetic resonance imaging, and histological analysis, we conduct a temporal investigation of CHIKV and MAYV replication in a wild-type mice model, focusing on the impact on SkM composition, structure, and repair in the acute and late phases of infection. We found that viral replication and induced inflammation promote a rapid loss of muscle mass and reduction in fiber cross-sectional area by upregulation of muscle-specific E3 ubiquitin ligases MuRF1 and Atrogin-1 expression, both key regulators of SkM fibers atrophy. Despite a reduction in inflammation and clearance of infectious viral particles, SkM atrophy persists until 30 days post-infection. The genomic CHIKV and MAYV RNAs were still detected in SkM in the late phase, along with the upregulation of chemokines and anti-inflammatory cytokine expression. In agreement with the involvement of inflammatory mediators on induced atrophy, the neutralization of TNF and a reduction in oxidative stress using monomethyl fumarate, an agonist of Nrf2, decreases atrogen expression and atrophic fibers while increasing weight gain in treated mice. These data indicate that arthritogenic alphavirus infection could chronically impact body SkM composition and also harm repair machinery, contributing to a better understanding of mechanisms of arthritogenic alphavirus pathogenesis and with a description of potentially new targets of therapeutic intervention.

Asunto(s)

Virus Chikungunya , Músculo Esquelético , Atrofia Muscular , Estrés Oxidativo , Animales , Atrofia Muscular/virología , Atrofia Muscular/metabolismo , Atrofia Muscular/patología , Ratones , Músculo Esquelético/patología , Músculo Esquelético/metabolismo , Músculo Esquelético/virología , Fiebre Chikungunya/patología , Fiebre Chikungunya/virología , Fiebre Chikungunya/metabolismo , Inflamación/patología , Inflamación/metabolismo , Inflamación/virología , Proteínas Musculares/metabolismo , Proteínas Musculares/genética , Replicación Viral , Ratones Endogámicos C57BL , Proteínas Ligasas SKP Cullina F-box/metabolismo , Proteínas Ligasas SKP Cullina F-box/genética , Infecciones por Alphavirus/virología , Infecciones por Alphavirus/patología , Infecciones por Alphavirus/metabolismo , Proteínas de Motivos Tripartitos/metabolismo , Proteínas de Motivos Tripartitos/genética , Modelos Animales de Enfermedad , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética

RESUMEN

Chikungunya virus (CHIKV) is a mosquito-transmitted, RNA virus that causes an often-severe musculoskeletal illness characterized by fever, joint pain, and a range of debilitating symptoms. The virus has re-emerged as a global health threat in recent decades, spreading from its origin in Africa across Asia and the Americas, leading to widespread outbreaks impacting millions of people. Despite more than 50 years of research into the pathogenesis of CHIKV, there is still no curative treatment available. Current management of CHIKV infections primarily involves providing supportive care to alleviate symptoms and improve the patient's quality of life. Given the ongoing threat of CHIKV, there is an urgent need to better understand its pathogenesis. This understanding is crucial for deciphering the mechanisms underlying the disease and for developing effective strategies for both prevention and management. This review aims to provide a comprehensive overview of CHIKV and its pathogenesis, shedding light on the complex interactions of viral genetics, host factors, immune responses, and vector-related factors. By exploring these intricate connections, the review seeks to contribute to the knowledge base surrounding CHIKV, offering insights that may ultimately lead to more effective prevention and management strategies for this re-emerging global health threat.

Asunto(s)

Fiebre Chikungunya , Virus Chikungunya , Humanos , Virus Chikungunya/patogenicidad , Virus Chikungunya/genética , Fiebre Chikungunya/virología , Fiebre Chikungunya/epidemiología , Animales , Virulencia , Mosquitos Vectores/virología , Interacciones Huésped-Patógeno

RESUMEN

BACKGROUND: Currently, there is no antiviral licensed to treat chikungunya fever, a disease caused by the infection with Alphavirus chikungunya (CHIKV). Treatment is based on analgesic and anti-inflammatory drugs to relieve symptoms. Our study aimed to evaluate the antiviral activity of sulfadoxine (SFX), an FDA-approved drug, and its derivatives complexed with silver(I) (AgSFX), salicylaldehyde Schiff base (SFX-SL), and with both Ag and SL (AgSFX-SL) against CHIKV. METHODS: The anti-CHIKV activity of SFX and its derivatives was investigated using BHK-21 cells infected with CHIKV-nanoluc, a marker virus-carrying nanoluciferase reporter. Dose-response and time of drug-addition assays were performed in order to assess the antiviral effects of the compounds, as well as in silico data and ATR-FTIR analysis for insights on their mechanisms of action. RESULTS: The SFX inhibited 34% of CHIKV replication, while AgSFX, SFX-SL, and AgSFX-SL enhanced anti-CHIKV activity to 84%, 89%, and 95%, respectively. AgSFX, SFX-SL, and AgSFX-SL significantly decreased viral entry and post-entry to host cells, and the latter also protected cells against infection. Additionally, molecular docking calculations and ATR-FTIR analysis demonstrated interactions of SFX-SL, AgSFX, and AgSFX-SL with CHIKV. CONCLUSIONS: Collectively, our findings suggest that the addition of metal ions and/or Schiff base to SFX improved its antiviral activity against CHIKV.

Asunto(s)

Antivirales , Fiebre Chikungunya , Virus Chikungunya , Sulfadoxina , Virus Chikungunya/efectos de los fármacos , Antivirales/farmacología , Antivirales/química , Animales , Línea Celular , Sulfadoxina/farmacología , Fiebre Chikungunya/tratamiento farmacológico , Fiebre Chikungunya/virología , Cricetinae , Bases de Schiff/farmacología , Plata/farmacología , Plata/química , Replicación Viral/efectos de los fármacos , Simulación del Acoplamiento Molecular , Relación Dosis-Respuesta a Droga , Humanos , Aldehídos

RESUMEN

Chikungunya virus (CHIKV) is a reemerging arbovirus causing disease on a global scale, and the potential for its epidemics remains high. CHIKV has caused millions of cases and heavy economic burdens around the world, while there are no available approved antiviral therapies to date. In this study, nifuroxazide, an FDA-approved antibiotic for acute diarrhea or colitis, was found to significantly inhibit a variety of arboviruses, although its antiviral activity varied among different target cell types. Nifuroxazide exhibited relatively high inhibitory efficiency in yellow fever virus (YFV) infection of the hepatoma cell line Huh7, tick-borne encephalitis virus (TBEV) and west nile virus (WNV) infection of the vascular endothelial cell line HUVEC, and CHIKV infection of both Huh7 cells and HUVECs, while it barely affected the viral invasion of neurons. Further systematic studies on the action stage of nifuroxazide showed that nifuroxazide mainly inhibited in the viral replication stage. In vivo, nifuroxazide significantly reduced the viral load in muscles and protected mice from CHIKV-induced footpad swelling, an inflammation injury within the arthrosis of infected mice. These results suggest that nifuroxazide has a potential clinical application as an antiviral drug, such as in the treatment of CHIKV infection.

Asunto(s)

Antivirales , Fiebre Chikungunya , Virus Chikungunya , Hidroxibenzoatos , Nitrofuranos , Replicación Viral , Animales , Ratones , Humanos , Virus Chikungunya/efectos de los fármacos , Virus Chikungunya/fisiología , Antivirales/farmacología , Antivirales/uso terapéutico , Replicación Viral/efectos de los fármacos , Nitrofuranos/farmacología , Nitrofuranos/uso terapéutico , Fiebre Chikungunya/tratamiento farmacológico , Fiebre Chikungunya/virología , Hidroxibenzoatos/farmacología , Hidroxibenzoatos/uso terapéutico , Línea Celular , Carga Viral/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana

RESUMEN

Chikungunya virus (CHIKV) is a single-stranded RNA virus belonging to the genus Alphavirus and is responsible for causing Chikungunya fever, a type of arboviral fever. Despite extensive research, the pathogenic mechanism of CHIKV within host cells remains unclear. In this study, an in-silico approach was used to predict that CHIKV produces micro-RNAs that target host-specific genes associated with host cellular regulatory pathways. Putative micro-RNAs of CHIKV were predicted using the miRNAFold and Vmir RNA structure web servers, and secondary structure prediction was performed using RNAfold. Host-specific target genes were then predicted, and hub genes were identified using CytoHubba and module selection through MCODE. Functional annotations of hub genes revealed their association with various pathways, including osteoclast differentiation, neuroactive ligand-receptor interaction, and mRNA surveillance. We used the freely available dataset GSE49985 to determine the level of expression of host-specific target genes and found that two genes, F-box and leucine-rich repeat protein 16 (FBXL16) and retinoic acid receptor alpha (RARA), were down-regulated, while four genes, RNA binding protein with serine-rich domain 1 (RNPS1), RNA helicase and ATPase (UPF1), neuropeptide S receptor 1 (NPSR1), and vasoactive intestinal peptide receptor 1 (VIPR1), were up-regulated. These findings provide insight into novel miRNAs and hub genes associated with CHIKV infection and suggest potential targets for therapeutic intervention. Further experimental validation of these targets could lead to the development of effective treatments for CHIKV-mediated diseases.

Asunto(s)

Virus Chikungunya , Biología Computacional , MicroARNs , Virus Chikungunya/genética , Virus Chikungunya/inmunología , MicroARNs/genética , Biología Computacional/métodos , Humanos , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Fiebre Chikungunya/virología , Fiebre Chikungunya/inmunología , Fiebre Chikungunya/genética , ARN Viral/genética , Redes Reguladoras de Genes

RESUMEN

BACKGROUND: Dengue virus (DENV) and Chikungunya virus (CHIKV) are major arboviruses that are transmitted to humans by Aedes aegypti (A. aegypti) and Aedes Albopictus (A. Albopictus) mosquitoes. In absence of specific antivirals and vaccine against these two viruses, prompt diagnosis of acute infections and robust surveillance for outbreak identification remain crucial. Therefore, rapid, robust, high-throughput, accessible, and low-cost assays are essential for endemic countries. This study evaluated our recently developed multiplex RT-PCR and RT-qPCR assays to screen for DENV1-4 and CHIKV circulation in Burkina Faso. METHODS AND RESULTS: This study, conducted between June to August 2023, enrolled patients with suspected arbovirus infection presenting at healthcare facilities in three Burkina Faso cities (Bobo-Dioulasso, Houndé, and Ouagadougou). Serum samples were collected and screened for DENV serotypes and CHIKV using our newly multiplex RT-PCR and RT-q PCR techniques recently developed. A total of 408 patients (age median = 33, range from 3 to 84 years) participated in this study. Of these, 13.7% (56/408) had DENV infection; DENV-1 was 32.1% (18/56) and DENV-3 was 67.9% (38/56). DENV-2, DENV-4 and CHIKV were not detected. CONCLUSIONS: This study demonstrates the effectiveness of our molecular methods for DENV detection and serotyping in Burkina Faso. The affordability of our methods makes them valuable for implementing widespread routine clinical diagnostics or arbovirus surveillance in resource-limited settings.

Asunto(s)

Fiebre Chikungunya , Virus Chikungunya , Virus del Dengue , Dengue , Humanos , Burkina Faso/epidemiología , Virus del Dengue/genética , Virus del Dengue/aislamiento & purificación , Virus Chikungunya/genética , Virus Chikungunya/aislamiento & purificación , Persona de Mediana Edad , Dengue/epidemiología , Dengue/virología , Dengue/diagnóstico , Dengue/sangre , Femenino , Adulto , Adolescente , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/virología , Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/sangre , Anciano , Masculino , Preescolar , Niño , Serogrupo , Anciano de 80 o más Años , Reacción en Cadena de la Polimerasa Multiplex/métodos , Adulto Joven , Monitoreo Epidemiológico , Animales , Aedes/virología

RESUMEN

In 2018-2019, Thailand experienced a nationwide spread of chikungunya virus (CHIKV), with approximately 15,000 confirmed cases of disease reported. Here, we investigated the evolutionary and molecular history of the East/Central/South African (ECSA) genotype to determine the origins of the 2018-2019 CHIKV outbreak in Thailand. This was done using newly sequenced clinical samples from travellers returning to Sweden from Thailand in late 2018 and early 2019 and previously published genome sequences. Our phylogeographic analysis showed that before the outbreak in Thailand, the Indian Ocean lineage (IOL) found within the ESCA, had evolved and circulated in East Africa, South Asia, and Southeast Asia for about 15 years. In the first half of 2017, an introduction occurred into Thailand from another South Asian country, most likely Bangladesh, which subsequently developed into a large outbreak in Thailand with export to neighbouring countries. Based on comparative phylogenetic analyses of the complete CHIKV genome and protein modelling, we identified several mutations in the E1/E2 spike complex, such as E1 K211E and E2 V264A, which are highly relevant as they may lead to changes in vector competence, transmission efficiency and pathogenicity of the virus. A number of mutations (E2 G205S, Nsp3 D372E, Nsp2 V793A), that emerged shortly before the outbreak of the virus in Thailand in 2018 may have altered antibody binding and recognition due to their position. This study not only improves our understanding of the factors contributing to the epidemic in Southeast Asia, but also has implications for the development of effective response strategies and the potential development of new vaccines.

Asunto(s)

Fiebre Chikungunya , Virus Chikungunya , Brotes de Enfermedades , Evolución Molecular , Genotipo , Filogenia , Virus Chikungunya/genética , Virus Chikungunya/clasificación , Virus Chikungunya/aislamiento & purificación , Humanos , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/virología , Tailandia/epidemiología , Genoma Viral , Suecia/epidemiología , Filogeografía , Mutación , Proteínas del Envoltorio Viral/genética

RESUMEN

Chikungunya virus (CHIKV) is a rapidly spreading re-emergent virus transmitted from mosquitoes to humans. The emergence of epidemic variants has been associated with changes in the viral genome, such as the duplication of repeated sequences in the 3' untranslated region (UTR). Indeed, blocks of repeated sequences seemingly favor RNA recombination, providing the virus with a unique ability to continuously change the 3'UTR architecture during host switching. In this work, we provide experimental data on the molecular mechanism of RNA recombination and describe specific sequence and structural elements in the viral 3'UTR that favor template switching of the viral RNA-dependent RNA polymerase on the 3'UTR. Furthermore, we found that a 3'UTR deletion mutant that exhibits markedly delayed replication in mosquito cells and impaired transmission in vivo, recombines in reference laboratory strains of mosquitoes. Altogether, our data provide novel experimental evidence indicating that RNA recombination can act as a nucleic acid repair mechanism to add repeated sequences that are associated to high viral fitness in mosquito during chikungunya virus replication.

Asunto(s)

Regiones no Traducidas 3' , Virus Chikungunya , Genoma Viral , ARN Viral , Recombinación Genética , Replicación Viral , Virus Chikungunya/genética , Regiones no Traducidas 3'/genética , ARN Viral/genética , ARN Viral/metabolismo , Animales , Replicación Viral/genética , Fiebre Chikungunya/virología , Fiebre Chikungunya/genética , Fiebre Chikungunya/transmisión , Humanos , Aedes/virología , Aedes/genética , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Línea Celular

RESUMEN

T-cell immunoglobin and mucin domain protein-1 (TIM-1) mediates entry of chikungunya virus (CHIKV) into some mammalian cells through the interaction with envelope phospholipids. While this interaction enhances entry, TIM-1 has been shown to tether newly formed HIV and Ebola virus particles, limiting their efficient release. In this study, we investigate the ability of surface receptors such as TIM-1 to sequester newly budded virions on the surface of infected cells. We established a luminescence reporter system to produce chikungunya viral particles that integrate nano-luciferase and easily quantify viral particles. We found that TIM-1 on the surface of host cells significantly reduced CHIKV release efficiency in comparison to other entry factors. Removal of cell surface TIM-1 through direct cellular knock-out or altering the cellular lipid distribution enhanced CHIKV release. Over the course of infection, CHIKV was able to counteract the tethering effect by gradually decreasing the surface levels of TIM-1 in a process mediated by the nonstructural protein 2. This study highlights the importance of phosphatidylserine receptors in mediating not only the entry of CHIKV but also its release and could aid in developing cell lines capable of enhanced vaccine production. IMPORTANCE: Chikungunya virus (CHIKV) is an enveloped alphavirus transmitted by the bites of infectious mosquitoes. Infection with CHIKV results in the development of fever, joint pain, and arthralgia that can become chronic and last for months after infection. Prevention of this disease is still highly focused on vector control strategies. In December 2023, a new live attenuated vaccine against CHIKV was approved by the FDA. We aimed to study the cellular factors involved in CHIKV release, to better understand CHIKV's ability to efficiently infect and spread among a wide variety of cell lines. We found that TIM-1 receptors can significantly abrogate CHIKV's ability to efficiently exit infected cells. This information can be beneficial for maximizing viral particle production in laboratory settings and during vaccine manufacturing.

Asunto(s)

Fiebre Chikungunya , Virus Chikungunya , Receptor Celular 1 del Virus de la Hepatitis A , Fosfatidilserinas , Liberación del Virus , Virus Chikungunya/fisiología , Virus Chikungunya/metabolismo , Receptor Celular 1 del Virus de la Hepatitis A/metabolismo , Humanos , Fosfatidilserinas/metabolismo , Fiebre Chikungunya/virología , Fiebre Chikungunya/metabolismo , Células HEK293 , Internalización del Virus , Animales , Envoltura Viral/metabolismo , Línea Celular , Virión/metabolismo , Receptores Virales/metabolismo

RESUMEN

Molecular surveillance is vital for monitoring arboviruses, often employing genus-specific quantitative reverse-transcription polymerase chain reaction (RT-qPCR). Despite this, an overlooked chikungunya fever outbreak occurred in Yunnan province, China, in 2019 and false negatives are commonly encountered during alphaviruses screening practice, highlighting the need for improved detection methods. In this study, we developed an improved alphaviruses-specific RT-qPCR capable of detecting chikungunya virus, eastern equine encephalitis virus, western equine encephalitis virus, Venezuelan equine encephalitis virus, Sindbis virus, Mayaro virus, and Ross River virus with high sensitivity and specificity. The assay identified three chikungunya virus-positive cases out of 188 sera retrospectively. Later genetic characterization suggested that imported cases from neighboring countries may be responsible for the neglected chikungunya fever outbreak of 2019 in Yunnan. Our findings underscore the value of improved alphaviruses-specific RT-qPCR in bolstering alphaviruses surveillance and informing preventive strategies.

Asunto(s)

Infecciones por Alphavirus , Alphavirus , Virus Chikungunya , Reacción en Cadena en Tiempo Real de la Polimerasa , Sensibilidad y Especificidad , Humanos , Alphavirus/genética , Alphavirus/aislamiento & purificación , Infecciones por Alphavirus/diagnóstico , Infecciones por Alphavirus/virología , Infecciones por Alphavirus/prevención & control , Infecciones por Alphavirus/epidemiología , China/epidemiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Virus Chikungunya/genética , Virus Chikungunya/aislamiento & purificación , Estudios Retrospectivos , Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/prevención & control , Fiebre Chikungunya/virología , Fiebre Chikungunya/epidemiología , Virus de la Encefalitis Equina del Este/genética , Brotes de Enfermedades/prevención & control , Virus Sindbis/genética , Virus de la Encefalitis Equina del Oeste/genética , Virus del Río Ross/genética , Virus del Río Ross/aislamiento & purificación , Virus de la Encefalitis Equina Venezolana/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , ARN Viral/genética

RESUMEN

Although the disease caused by chikungunya virus (CHIKV) is of great interest to public health organizations around the world, there are still no authorized antivirals for its treatment. Previously, dihalogenated anti-CHIKV compounds derived from L-tyrosine (dH-Y) were identified as being effective against in vitro infection by this virus, so the objective of this study was to determine the mechanisms of its antiviral action. Six dH-Y compounds (C1 to C6) dihalogenated with bromine or chlorine and modified in their amino groups were evaluated by different in vitro antiviral strategies and in silico tools. When the cells were exposed before infection, all compounds decreased the expression of viral proteins; only C4, C5 and C6 inhibited the genome; and C1, C2 and C3 inhibited infectious viral particles (IVPs). Furthermore, C1 and C3 reduce adhesion, while C2 and C3 reduce internalization, which could be related to the in silico interaction with the fusion peptide of the E1 viral protein. Only C3, C4, C5 and C6 inhibited IVPs when the cells were exposed after infection, and their effect occurred in late stages after viral translation and replication, such as assembly, and not during budding. In summary, the structural changes of these compounds determine their mechanism of action. Additionally, C3 was the only compound that inhibited CHIKV infection at different stages of the replicative cycle, making it a compound of interest for conversion as a potential drug.

Asunto(s)

Antivirales , Fiebre Chikungunya , Virus Chikungunya , Tirosina , Replicación Viral , Virus Chikungunya/efectos de los fármacos , Virus Chikungunya/fisiología , Tirosina/farmacología , Tirosina/análogos & derivados , Tirosina/metabolismo , Tirosina/química , Antivirales/farmacología , Antivirales/química , Fiebre Chikungunya/tratamiento farmacológico , Fiebre Chikungunya/virología , Animales , Replicación Viral/efectos de los fármacos , Chlorocebus aethiops , Células Vero , Humanos , Internalización del Virus/efectos de los fármacos , Proteínas Virales/metabolismo

RESUMEN

Arboviruses such as dengue, Zika, and chikungunya present similar symptoms in the early stages, which complicates their differential and timely diagnosis. In 2022, the PAHO published a guide to address this challenge. This study proposes a methodological framework that transforms qualitative information into quantitative information, establishing differential weights in relation to symptoms according to the medical evidence and the GRADE scale based on recommendation 1 of the said guide. To achieve this, common variables from the dataset were identified using the PAHO guide, and quality rules were established. A linear interpolation function was then parameterised to assign weights to the symptoms according to the evidence. Machine learning was used to compare the different models, achieving 99% accuracy compared with 79% without the methodology. This proposal represents a significant advancement, allowing the direct application of the PAHO recommendations to the dataset and improving the differential classification of arboviruses.

Asunto(s)

Fiebre Chikungunya , Dengue , Aprendizaje Automático , Dengue/diagnóstico , Dengue/virología , Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/virología , Humanos , Diagnóstico Diferencial , Virus del Dengue/clasificación , Virus del Dengue/genética , Virus del Dengue/aislamiento & purificación , Virus Chikungunya/clasificación , Virus Chikungunya/genética , Virus Chikungunya/aislamiento & purificación

RESUMEN

Dengue (DENV) and Chikungunya (CHIKV) viruses can be transmitted simultaneously by Aedes mosquitoes, and there may be co-infections in humans. However, how the adaptive immune response is modified in the host has yet to be known entirely. In this study, we analyzed the cross-reactivity and neutralizing activity of IgG antibodies against DENV and CHIKV in sera of patients from the Mexican Institute of Social Security in Veracruz, Mexico, collected in 2013 and 2015 and using IgG antibodies of BALB/c mice inoculated with DENV and/or CHIKV. Mice first inoculated with DENV and then with CHIKV produced IgG antibodies that neutralized both viruses. Mice were inoculated with CHIKV, and then with DENV; they had IgG antibodies with more significant anti-CHIKV IgG antibody neutralizing activity. However, the inoculation only with CHIKV resulted in better neutralization of DENV2. In sera obtained from patients in 2013, significant cross-reactivity and low anti-CHIKV IgG antibody neutralizing activity were observed. In CHIKV-positive 2015 sera, the anti-DENV IgG antibody neutralizing activity was high. These results suggest that CHIKV stimulates DENV2-induced memory responses and vice versa. Furthermore, cross-reactivity between the two viruses generated neutralizing antibodies, but exchanging CHIKV for DENV2 generated a better anti-CHIKV neutralizing response.

Asunto(s)

Anticuerpos Neutralizantes , Anticuerpos Antivirales , Fiebre Chikungunya , Virus Chikungunya , Reacciones Cruzadas , Virus del Dengue , Dengue , Inmunoglobulina G , Ratones Endogámicos BALB C , Animales , Virus Chikungunya/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Dengue/inmunología , Dengue/virología , Virus del Dengue/inmunología , Humanos , Fiebre Chikungunya/inmunología , Fiebre Chikungunya/virología , Reacciones Cruzadas/inmunología , Ratones , México , Femenino , Pruebas de Neutralización , Masculino , Coinfección/inmunología , Coinfección/virología , Adulto

RESUMEN

In a previous study to understand how the chikungunya virus (CHIKV) E1 glycoprotein ß-strand c functions, we identified several attenuating variants at E1 residue V80 and the emergence of second-site mutations in the fusion loop (E1-M88L) and hinge region (E1-N20Y) with the V80 variants in vivo. The emergence of these mutations led us to question how changes in E1 may contribute to CHIKV infection at the molecular level. Here, we use molecular dynamics to understand how changes in the E1 glycoprotein may influence the CHIKV glycoprotein E1-E2 complex. We found that E1 domain II variants lead to E2 conformational changes, allowing us to hypothesize that emerging variants E1-M88L and E1-N20Y could also change E2 conformation and function. We characterized CHIKV E1-M88L and E1-N20Y in vitro and in vivo to understand how these regions of the E1 glycoprotein contribute to host-specific infection. We found that CHIKV E1-N20Y enhanced infectivity in mosquito cells, while the CHIKV E1-M88L variant enhanced infectivity in both BHK-21 and C6/36 cells and led to changes in viral cholesterol-dependence. Moreover, we found that E1-M88L and E1-N20Y changed E2 conformation, heparin binding, and interactions with the receptor Mxra8. Interestingly, the CHIKV E1-M88L variant increased replication in Mxra8-deficient mice compared to WT CHIKV, yet was attenuated in mouse fibroblasts, suggesting that residue E1-M88 may function in a cell-type-dependent entry. Taken together, these studies show that key residues in the CHIKV E1 domain II and hinge region function through changes in E1-E2 dynamics to facilitate cell- and host-dependent entry.IMPORTANCEArboviruses are significant global public health threats, and their continued emergence around the world highlights the need to understand how these viruses replicate at the molecular level. The alphavirus glycoproteins are critical for virus entry in mosquitoes and mammals, yet how these proteins function is not completely understood. Therefore, it is critical to dissect how distinct glycoprotein domains function in vitro and in vivo to address these gaps in our knowledge. Here, we show that changes in the CHIKV E1 domain II and hinge alter E2 conformations leading to changes in virus-receptor and -glycosaminoglycan interactions and cell-specific infection. These results highlight that adaptive changes in E1 can have a major effect on virus attachment and entry, furthering our knowledge of how alphaviruses infect mammals and insects.

Asunto(s)

Fiebre Chikungunya , Virus Chikungunya , Proteínas del Envoltorio Viral , Virus Chikungunya/genética , Virus Chikungunya/fisiología , Animales , Proteínas del Envoltorio Viral/metabolismo , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/química , Ratones , Fiebre Chikungunya/virología , Humanos , Internalización del Virus , Conformación Proteica , Receptores Virales/metabolismo , Receptores Virales/genética , Mutación , Línea Celular , Unión Proteica , Simulación de Dinámica Molecular

RESUMEN

Chikungunya virus (CHIKV) causes a debilitating fever and joint pain, with no specific antiviral treatment available. Halogenated secondary metabolites from plants are a promising new class of drug candidates against chikungunya, with unique properties that make them effective against the virus. Plants produce these compounds to defend themselves against pests and pathogens, and they are effective against a wide range of viruses, including chikungunya. This study investigated the interactions of halogenated secondary metabolites with nsP2pro, a therapeutic target for CHIKV. A library of sixty-six halogenated plant metabolites screened previously for ADME properties was used. Metabolites without violation of Lipinski's rule were docked with nsP2pro using AutoDock Vina. To find the stability of the pipoxide chlorohydrin-nsP2pro complex, the GROMACS suite was used for MD simulation. The binding free energy of the ligand-protein complex was computed using MMPBSA. Molecular docking studies revealed that halogenated metabolites interact with nsP2pro, suggesting they are possible inhibitors. Pipoxide chlorohydrin showed the greatest affinity to the target. This was further confirmed by the MD simulations, surface accessible area, and MMPBSA studies. Pipoxide chlorohydrin, a halogenated metabolite, was the most potent against nsP2pro in the survey.

Asunto(s)

Antivirales , Virus Chikungunya , Simulación del Acoplamiento Molecular , Virus Chikungunya/efectos de los fármacos , Antivirales/farmacología , Antivirales/química , Antivirales/metabolismo , Fiebre Chikungunya/virología , Fiebre Chikungunya/tratamiento farmacológico , Metabolismo Secundario , Simulación de Dinámica Molecular , Halogenación , Plantas/química , Simulación por Computador , Proteínas no Estructurales Virales/metabolismo , Proteínas no Estructurales Virales/química

RESUMEN

We conducted a cross-sectional serosurvey for chikungunya virus (CHIKV) exposure in fruit bats in Senegal during 2020-2023. We found that 13.3% (89/671) of bats had CHIKV IgG; highest prevalence was in Eidolon helvum (18.3%, 15/82) and Epomophorus gambianus (13.7%, 63/461) bats. Our results suggest these bats are naturally exposed to CHIKV.

Asunto(s)

Anticuerpos Antivirales , Fiebre Chikungunya , Virus Chikungunya , Quirópteros , Animales , Quirópteros/virología , Senegal/epidemiología , Virus Chikungunya/inmunología , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/virología , Fiebre Chikungunya/sangre , Fiebre Chikungunya/historia , Estudios Seroepidemiológicos , Anticuerpos Antivirales/sangre , Estudios Transversales