RESUMEN
Crimean-Congo Hemorrhagic Fever Virus (CCHFV) is a globally significant vector-borne pathogen with no internationally-licensed preventative and therapeutic interventions. Hazara virus (HAZV), on the other hand, a related Orthonairovirus, has not been reported as a human pathogen. HAZV has been proposed as a surrogate model for studying CCHFV, bisosafety level 4 (BSL-4) agent. Previously, we investigated the humoral immune responses between NPs of these viruses and in this study, we extended the scrutiny to cellular immune responses elicited by NPs of CCHFV and HAZV. Here, mice were immunized with recombinant CCHFV NP and HAZV NP to evaluate the correlates of cell-mediated immunity (CMI). Delayed-type hypersensitivity (DTH) responses were assessed by challenging immunized mice with CCHFV-rNP or HAZV-rNP on the footpad and lymphocyte proliferation assays (LPAs) were performed by stimulating splenocytes in vitro with CCHFV-rNP or HAZV-rNP to compare cellular immune responses. In all test groups, strong DTH and LPA responses were detected against homologous and heterologous challenging antigens. To assess the cytokine response, an RT-qPCR -specific for cytokine mRNAs was utilized. Interestingly, CCHFV NP stimulated groups exhibited a significantly elevated mRNA level of interleukin 17 A (IL-17) compared to HAZV NP, indicating a notable difference in immune responses. This study presents comparison between CMI elicited by NPs of CCHFV and HAZV and contributes to the understanding of a highly pathogenic virus, particularly in the context of the declaration of CCHFV by World Health Organization's (WHO) as a major viral threat to the world.
Asunto(s)
Citocinas , Virus de la Fiebre Hemorrágica de Crimea-Congo , Inmunidad Celular , Animales , Virus de la Fiebre Hemorrágica de Crimea-Congo/inmunología , Citocinas/metabolismo , Ratones , Nucleoproteínas/inmunología , Ratones Endogámicos BALB C , Femenino , Hipersensibilidad Tardía/inmunología , Proliferación Celular , Bazo/inmunologíaRESUMEN
The World Health Organization estimates that there may be three billion people at risk of infection by Crimean-Congo Hemorrhagic Fever Virus (CCHFV), a highly lethal, emerging orthonairovirus carried by ticks. On the other hand, the closely related Hazara virus (HAZV), a member of the same serogroup, has not been reported as a pathogen for humans. Given the structural and phylogenetic similarities between these two viruses, we evaluated the immunological similarities of the nucleocapsid protein (NP) of these two viruses in multiple species. Strong antigenic similarities were demonstrated in anti-NP humoral immune responses against HAZV and CCHFV in multiple species using convalescent human CCHF sera, rabbit and mouse polyclonal antiserum raised against CCHFV, and mouse polyclonal antiserum against CCHFV-NP in enzyme immunoassays. We also report a convincing cross-reactivity between NPs in Western blots using HAZV-infected cell lysate as antigen and inactivated CCHFV and CCHFV-NP-immunized mice sera. These results suggest that NPs of HAZV and CCHFV share significant similarities in humoral responses across species and underline the potential utility of HAZV as a surrogate model for CCHFV.IMPORTANCE CCHFV and HAZV, members of the Nairoviridae family, are transmitted to mammals by tick bites. CCHFV is considered to be a severe threat to public health and causes hemorrhagic diseases with a high mortality rate, and there are neither preventative nor therapeutic medications against CCHFV disease. HAZV, on the other hand, is not a pathogen to humans and can be studied under BSL-2 conditions. The antigenic relationship between these viruses is of interest for vaccines and for preventative investigations. Here, we demonstrate cross-reactivity in anti-NP humoral immune response between NPs of HAZV and CCHFV in multiple species. These results underline the utility of HAZV as a surrogate model to study CCHFV infection.
RESUMEN
The recent pandemic of COVID-19 has caused a tremendous alarm around the world. Details of the infection process in the host have significant bearings on both recovery from the disease and on the correlates of the protection from the future exposures. One of these factors is the presence and titers of neutralizing Abs (NAbs) in infected people. In the current study, we set out to investigate NAbs in the recovered subjects discharged from the hospital in full health. Serum samples from a total of 49 documented consecutive COVID-19 subjects were included in the study. All the subjects were adults, and serum samples collected during the discharge were tested in viral neutralization, enzyme immunoassay (EIA), and Western immunoblot tests against viral Ags. Even though a majority of the recovered subjects had raised significant NAb titers, there is a substantial number of recovered patients (10 out of 49) with no or low titers of NAbs against the virus. In these cohorts as well as in patients with high NAb titers, viral Ag binding Abs were detectable in EIA tests. Both NAb titers and EIA detectable Abs are increased in patients experiencing a severe form of the disease, and in older patients the Ab titers were heightened. The main conclusion is that the recovery from SARS-CoV-2 infection is not solely dependent on high NAb titers in affected subjects, and this recovery process is probably produced by a complex interplay between many factors, including immune response, age of the subjects, and viral pathology.
Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Betacoronavirus/metabolismo , Infecciones por Coronavirus/sangre , Neumonía Viral/sangre , Adulto , Animales , COVID-19 , Chlorocebus aethiops , Infecciones por Coronavirus/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Neutralización , Pandemias , Neumonía Viral/terapia , SARS-CoV-2 , Células VeroRESUMEN
The Fonsecaea species, which are the leading causes of chromoblastomycosis, are not considered neurotropic fungal agents. Fonsecaea pedrosoi is the primary species in the genus and is usually isolated from chromoblastomycosis cases. However, the recently distinguished species F. monophora has been reported in a few cerebral phaeohyphomycosis cases. Here, a case of cerebral phaeohyphomycosis caused by Fonsecaea monophora is presented in a 71-year-old female subject with chronic diabetes mellitus and hypertension. The identification of F. monophora was made through mycological and molecular analysis, and an isolate was differentiated from the closely related F. pedrosoi by sequence data on key bases on the ribosomal internal transcribed spacer region. The case was successfully treated with surgical and medical approaches, and the patient has remained healthy and stable after a ten-month follow up. Given the increasing incidence of this type of infection of the central nervous system (CNS), this case provides further support for the consideration that F. monophora might represent a neurotropic agent.
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Ascomicetos/genética , Ascomicetos/aislamiento & purificación , Feohifomicosis Cerebral/microbiología , Hongos Mitospóricos/genética , Hongos Mitospóricos/aislamiento & purificación , Anciano , Ascomicetos/ultraestructura , Feohifomicosis Cerebral/diagnóstico , Feohifomicosis Cerebral/tratamiento farmacológico , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Complicaciones de la Diabetes , Femenino , Humanos , Hipertensión/complicaciones , Técnicas de Tipificación Micológica , Filogenia , Análisis de Secuencia de ADNRESUMEN
Crimean-Congo hemorrhagic fever virus (CCHFV) is an orthonairovirus from the Bunyavirales order that is widely distributed geographically and causes severe or fatal infections in humans. The viral genome consists of three segmented negative-sense RNA molecules. The CCHFV nucleocapsid protein (CCHFV NP) is encoded by the smallest segment of the virus. CCHFV NP, the primary function of which is the encapsidation of viral RNA molecules, plays a critical role in various mechanisms important for viral replication and pathogenesis. This review is an attempt to revisit the literature available on the highly immunogenic and highly conserved CCHFV NP, summarizing the multifunctional roles of this protein in the immunology of CCHFV. Specifically, the review addresses the impact of CCHFV NP on innate, humoral, and cellular immune responses, epitopes recognized by B and T cells that limit viral spread, and its role as a target for diagnostic tests and for vaccine design. Based on the extensive information generated by many research groups, it could be stated that NP constitutes a significant and critical player in the immunology of CCHFV.
Asunto(s)
Virus de la Fiebre Hemorrágica de Crimea-Congo , Fiebre Hemorrágica de Crimea , Proteínas de la Nucleocápside , Virus de la Fiebre Hemorrágica de Crimea-Congo/inmunología , Virus de la Fiebre Hemorrágica de Crimea-Congo/genética , Humanos , Proteínas de la Nucleocápside/inmunología , Fiebre Hemorrágica de Crimea/inmunología , Fiebre Hemorrágica de Crimea/virología , Animales , Inmunidad Celular , Inmunidad Innata , Replicación Viral , Anticuerpos Antivirales/inmunologíaRESUMEN
Multilocus DNA sequencing has identified a nonarchetypal strain of Toxoplasma gondii as the causal agent of a waterborne outbreak in Brazil in 2001. The strain, isolated from a water supply epidemiologically linked to the outbreak, was virulent to mice, and it has previously been identified as BrI. Using a serologic assay that detects strain-specific antibodies, we found that 13 (65%) of 20 individuals who were immunoglobulin (Ig) M positive during the outbreak possessed the same serotype as mice infected with the purported epidemic strain. The remaining 7 individuals, plus additional IgM-negative, IgG-positive individuals, possessed 1 of 4 novel serotypes, the most common of which matched the serotype of mice infected with strains isolated from chickens foraging near the outbreak site. The latter strains likely reflect the genetic diversity of T. gondii circulating in highly endemic regions of Brazil. The serotyping assay proved a useful tool for identification of specific individuals infected with the outbreak agent.
Asunto(s)
Brotes de Enfermedades , Toxoplasma/clasificación , Toxoplasma/genética , Toxoplasmosis/epidemiología , Toxoplasmosis/parasitología , Microbiología del Agua , Animales , Brasil/epidemiología , Ensayo de Inmunoadsorción Enzimática , Genotipo , Humanos , Ratones , Serotipificación , Especificidad de la Especie , Toxoplasma/aislamiento & purificaciónRESUMEN
Background: Polymyxin B and colistin have similar structures except for one amino acid. Usually, physicians choose either polymyxin B or colistin for treatment of infections caused by multidrug-resistant (MDR) organisms. The preference is based on previous experience. Not much data are found in the literature comparing the two drugs against the same microorganisms. In this study, we compared in vitro antimicrobial activities of the two polymyxins against a panel of highly resistant and susceptible microorganisms. Methods: Eighty-nine clinical isolates (27 Klebsiella pneumoniae, 31 Acinetobacter baumannii and 31 Pseudomonas aeruginosa) were tested in broth microdilution assays. Time-kill curve experiments were carried out on selected isolates. Results: Significantly lower MICs for polymyxin B than for colistin were found against all species tested including K. pneumoniae (p < .02), A. baumannii (p < .001) and P. aeruginosa (p < .01). The low MICs caused a change in categorical interpretations of only two K. pneumoniae and two P. aeruginosa. Similar results were obtained in time-kill curve experiments with both susceptible and resistant clinical isolates. Conclusions: Significantly lower MICs were found for polymyxin B against three of the most critical MDR species. Even though differences in categorical interpretations were not striking, lower MICs might be a critical consideration in clinical management of select cases where the concentration of these toxic antibiotics matters because of underlying co-morbidities. These results provide support to previous suggestions that re-consideration of breakpoint interpretations for polymyxins might be needed.
Asunto(s)
Antibacterianos/farmacología , Colistina/farmacología , Farmacorresistencia Bacteriana Múltiple , Bacterias Gramnegativas/efectos de los fármacos , Polimixina B/farmacología , Acinetobacter baumannii/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/microbiología , Humanos , Klebsiella pneumoniae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/efectos de los fármacosRESUMEN
Hand, foot, and mouth disease (HFMD) is caused by various serotypes of Enterovirus genus. Coxsackievirus A16 (CV-A16) and enterovirus A71 (EV-A71) were known to be the only responsible agents for these epidemics; however, this opinion was challenged after the detection that coxsackievirus A6 (CV-A6) was the responsible species for the outbreak in Finland in 2008. HFMD is frequently seen in Turkey, and no detailed study on its clinical and microbiological epidemiology has previously been reported. The present study addresses this question. Twenty-seven patient samples collected between 2015 and 2017 were included in the study. Typing was conducted by RT-PCR and the sequencing applied directly to patient's samples and as well as to the viral cultures with pan-enterovirus and serotype-specific primers. The presence of Enterovirus in 12 of 27 HFMD samples was shown with RT-PCR. The causative agent for three of these 12 samples was CV-A16, one of the most frequent two serotypes around the world, and the remaining nine samples was CV-A6. The findings of the study are relevant since it pertains to the molecular epidemiology of HFMD in Turkey, a gateway country where different serotypes might be circulating and transmitted. The findings also support the notion that CV-A6 cases are rising in number, which has caused more severe clinical features and widespread rashes in recent outbreaks.Hand, foot, and mouth disease (HFMD) is caused by various serotypes of Enterovirus genus. Coxsackievirus A16 (CV-A16) and enterovirus A71 (EV-A71) were known to be the only responsible agents for these epidemics; however, this opinion was challenged after the detection that coxsackievirus A6 (CV-A6) was the responsible species for the outbreak in Finland in 2008. HFMD is frequently seen in Turkey, and no detailed study on its clinical and microbiological epidemiology has previously been reported. The present study addresses this question. Twenty-seven patient samples collected between 2015 and 2017 were included in the study. Typing was conducted by RT-PCR and the sequencing applied directly to patient's samples and as well as to the viral cultures with pan-enterovirus and serotype-specific primers. The presence of Enterovirus in 12 of 27 HFMD samples was shown with RT-PCR. The causative agent for three of these 12 samples was CV-A16, one of the most frequent two serotypes around the world, and the remaining nine samples was CV-A6. The findings of the study are relevant since it pertains to the molecular epidemiology of HFMD in Turkey, a gateway country where different serotypes might be circulating and transmitted. The findings also support the notion that CV-A6 cases are rising in number, which has caused more severe clinical features and widespread rashes in recent outbreaks.
Asunto(s)
Enterovirus Humano B/aislamiento & purificación , Enfermedad de Boca, Mano y Pie/epidemiología , Enfermedad de Boca, Mano y Pie/virología , Epidemiología Molecular/métodos , Animales , Línea Celular , Niño , Preescolar , Chlorocebus aethiops , Enterovirus Humano B/clasificación , Enterovirus Humano B/genética , Femenino , Humanos , Lactante , Masculino , Tipificación Molecular , Turquía/epidemiología , Células VeroRESUMEN
BACKGROUND: Molluscum contagiosum has a worldwide occurrence and its primary mode of transmission is via direct human contact including sexual means. The aim of the study was to implement a polymerase chain reaction-based assay for detection and subtyping of Molluscum contagiosum virus (MCV) in skin lesions diagnosed with molluscum contagiosum in a large regional teaching hospital in Turkey. METHODS: For this purpose, a total of 61 patients were included in the study. Randomly selected single lesion from each patient was used to extract DNA material and a specific PCR reaction amplifying 393-bp- and 575-bp-long regions from MCV genome was used in the detection. Subtyping was carried out by digestion of the amplified 575-bp product with restriction endonuclease enzyme BamHI. Both amplified and restriction enzyme digested products visualized on agarose gel electrophoresis. RESULTS: All 61 molluscum cases (100%) included in the study contained MCV genetic material as demonstrated by the presence of 393- and 575-bp-long PCR amplified products. Restriction enzyme BamHI digestion of the 575-bp-long amplicon indicated that the infecting subtype in all the cases (100%) was MCV subtype I. CONCLUSIONS: Results of this study demonstrate that subtype I is the only infecting strain dominant in our region. Because the only consecutive molluscum patients admitted to our hospital were included in the study, our data do not rule out the possibility that other genotypes might be present in the Turkish population. However, it is not unreasonable to conclude that similar trends exist in the rest of the country. Results also show that a molecular-based diagnostic assay would be feasible in cases where diagnosis was deemed necessary.
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Molusco Contagioso/diagnóstico , Molusco Contagioso/virología , Virus del Molusco Contagioso/clasificación , Virus del Molusco Contagioso/aislamiento & purificación , Adolescente , Adulto , Niño , Preescolar , ADN Viral/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Virus del Molusco Contagioso/genética , TurquíaRESUMEN
OBJECTIVE: To investigate etiological role of Epstein-Barr virus (EBV) DNA in breast cancer. MATERIALS AND METHODS: The presence of EBV DNA in 57 breast cancer tissues was investigated with a sensitive PCR assay. The breast cancer tissues were from invasive ductular (n=28), lobular (n=20) and other miscellaneous carcinomas (n=9). Tissues from normal breasts and patients with various benign breast diseases (n=55): fibrocystic disease (n=34), fibroadenoma (n=16), hyperplasia, and granulomatous mastitis (n=5), were used as control samples. RESULTS: EBV DNA was detected in 13 (23%) cancerous tissues (7 ductular, 4 lobular, 2 other carcinoma) and 19 (35%) in the control tissues. The difference between EBV presence in malignant and benign tissues was not statistically significant (p>0.05). CONCLUSION: The presence of EBV DNA was detected almost equally in both breast cancer and normal tissues, which indicates no etiological role for EBV in breast cancer. We suggest further etiological studies.
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Neoplasias de la Mama/virología , Carcinoma Lobular/virología , Herpesvirus Humano 4/aislamiento & purificación , Adolescente , Adulto , Distribución por Edad , Anciano , Neoplasias de la Mama/etiología , Carcinoma Lobular/etiología , Estudios de Casos y Controles , ADN Viral/análisis , Electroforesis en Gel de Agar , Femenino , Formaldehído , Herpesvirus Humano 4/patogenicidad , Humanos , Persona de Mediana Edad , Adhesión en Parafina , Reacción en Cadena de la Polimerasa , Prevalencia , TurquíaRESUMEN
OBJECTIVES: To study the prevalence and genotype distribution of hepatitis G virus (HGV) in hemodialysis patients in East Anatolia, Turkey. SUBJECTS AND MATERIALS: Eighty-nine hemodialysis patients and 30 healthy individuals were analyzed by using reverse-transcriptase nested polymerase chain reaction with primers specific for 5' untranslated region. HGV genotyping was performed by PCR and three randomly selected HGV-positive samples were sequenced. RESULTS: Of the 89 hemodialysis patients, HGV RNA was detected in 9 (10.2%). All of our isolates were assigned to genotype 2. CONCLUSION: Our results showed that hemodialysis patients carry the risk for HGV infection in East Anatolia, Turkey.