RESUMEN
Hemorrhagic disease due to elephant endotheliotropic herpesvirus infection (EEHV-HD) is an important cause of calf mortality in managed and free-ranging Asian (Elephas maximus) and African elephant (Loxodonta spp.) populations. Consequently, infection has profound implications for elephant population growth and sustainability. The mechanisms of disease caused by EEHV (i.e., infection, dissemination, shedding, latency) are relatively undefined, in part because of a lack of robust validated assays for detecting viral gene products in relevant samples. To address this issue, we used RNAscope® in situ hybridization (ISH) based on EEHV1A DNA polymerase and terminase genes to detect EEHV1A RNA in archival formalin-fixed, paraffin-embedded Asian elephant heart and tongue from PCR-confirmed cases (n = 4) of EEHV-HD and Asian elephants (n = 2) that died from other causes. EEHV1A-positive cases had positive hybridization signal in endothelial cell nuclei of both tissues for both DNA polymerase and terminase. EEHV-negative cases lacked signal. In positive cases, the number of positive nuclei was manually assessed to provide an estimate of the viral load and compare sensitivity of the two probes. In all cases, heart had greater signal than tongue for both probes (Wilcoxon rank test; P ≤ 0.01). Overall, terminase hybridization signal was greater than DNA polymerase signal (Wilcoxon rank test; P ≤ 0.01). Results indicate RNAscope ISH is a valuable tool for detection of EEHV in archival samples and for confirming infection. Additionally, the terminase gene is the optimal target and heart is preferable to tongue for detection in cases of EEHV-HD. Results will inform future investigations of viral tropism in EEHV-HD cases due to EEHV1A.
Asunto(s)
Infecciones por Herpesviridae , Herpesviridae , Animales , Herpesviridae/genética , Infecciones por Herpesviridae/diagnóstico , Infecciones por Herpesviridae/veterinaria , Infecciones por Herpesviridae/epidemiología , Hibridación in Situ/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , ADN Polimerasa Dirigida por ADNRESUMEN
Novel diagnostic and therapeutic methods were utilized in the successful management of severe elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV-HD) in a 1.9-yr-old captive Asian elephant (Elephas maximus). High levels of EEHV1A viremia were detected for 12 d. In addition to established EEHV treatments, therapies included famciclovir-fortified elephant whole blood and plasma, mesenchymal stem cells harvested from elephant umbilical tissue, and aminocaproic acid. Testing conducted to examine the effects of EEHV infection on hemostasis suggested marked intravascular coagulation with decreased plasminogen activity and increased D-dimer concentrations. Thromboelastography was used to assess the efficacy of aminocaproic acid and demonstrated hypofibrinolysis on samples taken after drug administration, as compared with samples from healthy adult Asian elephants. A serological assay for a novel EEHV1A-specific antibody marker (E52) was developed due to lack of seroconversion to a previously established EEHV1A-specific antibody marker (ORFQ) and showed a sustained increase after EEHV-HD illness.
Asunto(s)
Elefantes , Infecciones por Herpesviridae , Herpesviridae , Animales , Famciclovir , Infecciones por Herpesviridae/diagnóstico , Infecciones por Herpesviridae/tratamiento farmacológico , Infecciones por Herpesviridae/veterinaria , Viremia/veterinariaRESUMEN
Elephant endotheliotropic herpesvirus (EEHV) can cause lethal hemorrhagic disease in juvenile Asian elephants, both in captivity and in the wild. Most deaths associated with the virus are caused by two chimeric variants of EEHV1 (EEHV1A and EEHV1B), while two other EEHVs endemic within Asian elephants (EEHV4 and EEHV5) have been recognized but cause death less often. Whether lethal EEHV infections are due to primary infection or reactivation of latent virus remains unknown, and knowledge of the anti-EEHV antibody levels in young elephants is limited. To close these gaps, we sought to develop a serologic assay capable of distinguishing among infections with different EEHVs using a luciferase immunoprecipitation system (LIPS) for antibody profiling and a panel of conserved EEHV recombinant proteins and proteins unique to EEHV1. The results showed that elephants dying from EEHV1 hemorrhagic disease or ill from EEHV infection were seronegative for the EEHV species that caused the disease or illness, indicating that the events were associated with primary infection rather than reactivation of latent virus. We also demonstrated that waning of EEHV1-specific antibodies can occur in the first 2 years of life, when a threshold protective level of antibody may be needed to prevent severe EEHV1-related disease. Use of the LIPS assay to identify putative "diagnostic" proteins would be a valuable asset in determining the EEHV immune status of young elephants and responses to candidate EEHV vaccines in the future.IMPORTANCE Whether clinical illness and deaths associated with elephant endotheliotropic herpesvirus (EEHV) infection result from primary infection or reactivation of latent virus is a longstanding question in the field. By applying a relatively new assay, the luciferase immunoprecipitation system (LIPS), combined with the genomic sequences of the viruses, we gained the insights and tools needed to resolve this issue. Our EEHV1-specific LIPS assay should be useful for assessing the vulnerability of elephant calves to infection with different EEHVs and evaluating antibody responses to anti-EEHV vaccines. A significant proportion of the Asian elephant population is under some form of human care. Hence, the ability to screen for EEHV immune status in elephant calves should have a major impact on the management of these animals worldwide.
Asunto(s)
Enfermedades de los Animales/virología , Elefantes/virología , Infecciones por Herpesviridae/veterinaria , Infecciones por Herpesviridae/virología , Herpesviridae/patogenicidad , Enfermedades de los Animales/diagnóstico , Enfermedades de los Animales/prevención & control , Animales , Anticuerpos Antivirales/sangre , Antígenos Virales/inmunología , Femenino , Herpesviridae/genética , Herpesviridae/inmunología , Infecciones por Herpesviridae/inmunología , Infecciones por Herpesviridae/prevención & control , Vacunas contra Herpesvirus , Masculino , Pruebas Serológicas , Proteínas Virales/genética , Proteínas Virales/inmunologíaRESUMEN
Elephant endotheliotropic herpesvirus (EEHV) hemorrhagic disease (EEHV-HD) threatens Asian elephant (Elephas maximus) population sustainability in North America. Clusters of cases have also been reported in African elephants (Loxodonta africana). Risk to range country elephant populations is unknown. Currently, EEHV detection depends upon sampling elephants trained for invasive blood and trunk wash collection. To evaluate noninvasive sample collection options, paired invasively collected (blood, trunk wash and oral swabs), and noninvasively collected (chewed plant and fecal) samples were compared over 6 wk from 9 Asian elephants and 12 African elephants. EEHV shedding was detected simultaneously in a paired trunk wash and fecal sample from one African elephant. Elephant γ herpesvirus-1 shedding was identified in six chewed plant samples collected from four Asian elephants. Noninvasively collected samples can be used to detect elephant herpesvirus shedding. Longer sampling periods are needed to evaluate the clinical usefulness of noninvasive sampling for EEHV detection.
Asunto(s)
Betaherpesvirinae/aislamiento & purificación , Elefantes , Infecciones por Herpesviridae/veterinaria , Manejo de Especímenes/veterinaria , Alimentación Animal/virología , Animales , Animales de Zoológico , Recolección de Muestras de Sangre/veterinaria , Heces/virología , Femenino , Microbiología de Alimentos , Infecciones por Herpesviridae/diagnóstico , Infecciones por Herpesviridae/virología , Irlanda , Masculino , Manejo de Especímenes/clasificación , Manejo de Especímenes/instrumentaciónRESUMEN
Elephant endotheliotropic herpesvirus (EEHV) can cause lethal hemorrhagic disease in juvenile Asian elephants, an endangered species. One hypothesis to explain this vulnerability of some juvenile elephants is that they fail to mount an effective T cell response to the virus. To our knowledge, there have been no studies of Asian elephant T cell responses to EEHV. To address this deficiency, we validated the gamma interferon (IFN-γ) enzyme-linked immunospot assay for tracking antigen-directed T cell activity by monitoring rabies-specific responses in vaccinated elephants. In addition, we generated monoclonal antibodies to Asian elephant CD4 and CD8 to facilitate phenotypic T cell profiling. Using these tools, we screened healthy elephants with a history of EEHV infection for reactivity against nine EEHV proteins whose counterparts in other herpesviruses are known to induce T cell responses in their natural hosts. We identified glycoprotein B (gB) and the putative regulatory protein E40 as the most immunogenic T cell targets (IFN-γ responses in five of seven elephants), followed by the major capsid protein (IFN-γ responses in three of seven elephants). We also observed that IFN-γ responses were largely from CD4+ T cells. We detected no activity against the predicted major immediate early (E44) and large tegument (E34) proteins, both immunodominant T cell targets in humans latently infected with cytomegalovirus. These studies identified EEHV-specific T cells in Asian elephants for the first time, lending insight into the T cell priming that might be required to protect against EEHV disease, and will guide the design of effective vaccine strategies.IMPORTANCE Endangered Asian elephants are facing many threats, including lethal hemorrhagic disease from elephant endotheliotropic herpesvirus (EEHV). EEHV usually establishes chronic, benign infections in mature Asian elephants but can be lethal to juvenile elephants in captivity and the wild. It is the leading cause of death in captive Asian elephants in North America and Europe. Despite the availability of sensitive tests and protocols for treating EEHV-associated illness, these measures are not always effective. The best line of defense would be a preventative vaccine. We interrogated normal healthy elephants previously infected with EEHV for T cell responses to nine EEHV proteins predicted to induce cellular immune responses. Three proteins elicited IFN-γ responses, suggesting their potential usefulness as vaccine candidates. Our work is the first to describe T cell responses to a member of the proposed fourth subfamily of mammalian herpesviruses, the Deltaherpesvirinae, within a host species in the clade Afrotheria. An EEHV vaccine would greatly contribute to the health care of Asian and African elephants that are also susceptible to this disease.
Asunto(s)
Elefantes/virología , Infecciones por Herpesviridae/inmunología , Infecciones por Herpesviridae/veterinaria , Herpesviridae/inmunología , Linfocitos T/inmunología , Viremia/inmunología , Viremia/veterinaria , Animales , Asia/epidemiología , Femenino , Infecciones por Herpesviridae/epidemiología , Infecciones por Herpesviridae/virología , Masculino , Viremia/epidemiología , Viremia/virologíaRESUMEN
Epstein-Barr virus (EBV) is a γ-herpesvirus that may cause infectious mononucleosis in young adults. In addition, epidemiological and molecular evidence links EBV to the pathogenesis of lymphoid and epithelial malignancies. EBV has the unique ability to transform resting B cells into permanently proliferating, latently infected lymphoblastoid cell lines. Epstein-Barr virus nuclear antigen 2 (EBNA-2) is a key regulator of viral and cellular gene expression for this transformation process. The N-terminal region of EBNA-2 comprising residues 1-58 appears to mediate multiple molecular functions including self-association and transactivation. However, it remains to be determined if the N-terminus of EBNA-2 directly provides these functions or if these activities merely depend on the dimerization involving the N-terminal domain. To address this issue, we determined the three-dimensional structure of the EBNA-2 N-terminal dimerization (END) domain by heteronuclear NMR-spectroscopy. The END domain monomer comprises a small fold of four ß-strands and an α-helix which form a parallel dimer by interaction of two ß-strands from each protomer. A structure-guided mutational analysis showed that hydrophobic residues in the dimer interface are required for self-association in vitro. Importantly, these interface mutants also displayed severely impaired self-association and transactivation in vivo. Moreover, mutations of solvent-exposed residues or deletion of the α-helix do not impair dimerization but strongly affect the functional activity, suggesting that the EBNA-2 dimer presents a surface that mediates functionally important intra- and/or intermolecular interactions. Our study shows that the END domain is a novel dimerization fold that is essential for functional activity. Since this specific fold is a unique feature of EBNA-2 it might provide a novel target for anti-viral therapeutics.
Asunto(s)
Antígenos Nucleares del Virus de Epstein-Barr/química , Proteínas Mutantes/química , Transactivadores/genética , Activación Transcripcional , Proteínas Virales/química , Adulto , Secuencia de Aminoácidos , Western Blotting , Cristalografía por Rayos X , Antígenos Nucleares del Virus de Epstein-Barr/genética , Técnica del Anticuerpo Fluorescente , Células HeLa , Humanos , Técnicas para Inmunoenzimas , Inmunoprecipitación , Datos de Secuencia Molecular , Proteínas Mutantes/genética , Mutación/genética , Resonancia Magnética Nuclear Biomolecular , Conformación Proteica , Multimerización de Proteína , Estructura Terciaria de Proteína , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Proteínas Virales/genéticaRESUMEN
This epidemiologic study follows a 5-yr-old male African elephant ( Loxodonta africana ) during an episode of hemorrhagic disease (HD) due to elephant endotheliotropic herpesvirus 3B (EEHV3B) utilizing data from complete blood counts, electrophoresis and acute phase protein analysis, and polymerase chain reaction (PCR) of multiple body fluids during and after the clinical episode. The elephant presented with sudden onset of marked lethargy and inappetence followed by hypersalivation, hyperemia of the conjunctivae and focally on the tongue, and swellings on the head and ventrum. A moderate leukocytopenia with band neutrophilia, lymphopenia, monocytopenia, and thrombocytophilia was followed by a rise in all three cell types by day 10. Moderate increases in serum amyloid A and C-reactive protein were noted in the first weeks of illness. Conventional PCR of whole blood yielded a strong positive result for EEHV3B. Quantitative PCR revealed moderate viremia, which slowly returned to undetectable levels by day 35 of treatment. EEHV3B was shed in trunk wash samples starting at day 22 for 10 days at moderate levels, and then at low levels for up to 8.5 mo. All three female herd mates shed low levels of EEHV3B in trunk washes intermittently starting from day 28 of the calf's illness until over 7 mo afterward. The majority of saliva samples from the calf over the 8.5-mo period were also positive for EEHV3B. A subfraction of saliva samples from a female herdmate was positive from days 127-190 following disease onset in the calf. Four elephant gammaherpesviruses were detected sporadically from the calf and female herdmates during this same time period. Treatment was started at the onset of clinical signs and consisted of rectal and oral fluids and oral famciclovir. This is the first case of EEHV3B HD in an elephant species and the first thorough epidemiologic evaluation of EEHV HD in an African elephant.
Asunto(s)
Elefantes/virología , 2-Aminopurina/análogos & derivados , 2-Aminopurina/uso terapéutico , Animales , Antivirales/uso terapéutico , Famciclovir , Herpesviridae/aislamiento & purificación , Infecciones por Herpesviridae/veterinaria , Masculino , Saliva/virologíaRESUMEN
While all herpesviruses can switch between lytic and latent life cycle, which are both driven by specific transcription programs, a unique feature of latent EBV infection is the expression of several distinct and well-defined viral latent transcription programs called latency I, II, and III. Growth transformation of B-cells by EBV in vitro is based on the concerted action of Epstein-Barr virus nuclear antigens (EBNAs) and latent membrane proteins(LMPs). EBV growth-transformed B-cells express a viral transcriptional program, termed latency III, which is characterized by the coexpression of EBNA2 and EBNA-LP with EBNA1, EBNA3A, -3B, and -3C as well as LMP1, LMP2A, and LMP2B. The focus of this review will be to discuss the current understanding of how two of these proteins, EBNA2 and EBNA-LP, contribute to EBV-mediated B-cell growth transformation.
Asunto(s)
Infecciones por Virus de Epstein-Barr/virología , Antígenos Nucleares del Virus de Epstein-Barr/metabolismo , Herpesvirus Humano 4/metabolismo , Proteínas Virales/metabolismo , Animales , Linfocitos B/virología , Transformación Celular Viral , Antígenos Nucleares del Virus de Epstein-Barr/genética , Regulación Viral de la Expresión Génica , Herpesvirus Humano 4/genética , Humanos , Proteínas Virales/genéticaRESUMEN
The ability of prior infection from one elephant endotheliotropic herpesvirus (EEHV) type to protect against clinical or lethal infection from others remains an important question. This report describes viremia and subsequent shedding of EEHV1B in two juvenile 4-yr-old Asian elephants within 3 wk or 2 mo following significant infections caused by the rarely seen EEHV4. High levels of EEHV1B shedding were detected in the first elephant prior to emergence of infection and viremia in the second animal. The EEHV1B virus associated with both infections was identical to the strain causing infection in two herd mates previously. High EEHV viremia correlated with leukopenia and thrombocytopenia, which was followed by leukocytosis and thrombocytosis when clinical signs started to resolve. The observations from these cases should be beneficial for helping other institutions monitor and treat elephants infected with EEHV1, the most common virus associated with lethal hemorrhagic disease.
Asunto(s)
Animales de Zoológico , Elefantes , Infecciones por Herpesviridae/veterinaria , Herpesviridae/clasificación , 2-Aminopurina/análogos & derivados , 2-Aminopurina/uso terapéutico , Animales , Antivirales/uso terapéutico , Famciclovir , Herpesviridae/genética , Infecciones por Herpesviridae/tratamiento farmacológico , Infecciones por Herpesviridae/epidemiología , Infecciones por Herpesviridae/virologíaRESUMEN
Elephant endotheliotropic herpesvirus (EEHV) can cause lethal hemorrhagic disease in juvenile Asian elephants. A number of EEHV types and subtypes exist, where most deaths have been caused by EEHV1A and EEHV1B. EEHV4 has been attributed to two deaths, but as both diagnoses were made postmortem, EEHV4 disease has not yet been observed and recorded clinically. In this brief communication, two cases of EEHV4 infection in juvenile elephants at the Houston Zoo are described, where both cases were resolved following intensive treatment and administration of famciclovir. A quantitative real-time polymerase chain reaction detected EEHV4 viremia that correlated with clinical signs. High levels of EEHV4 shedding from trunk wash secretions of the first viremic elephant correlated with subsequent infection of the second elephant with EEHV4. It is hoped that the observations made in these cases--and the successful treatment regimen used--will help other institutions identify and treat EEHV4 infection in the future.
Asunto(s)
Animales de Zoológico , Elefantes , Infecciones por Herpesviridae/veterinaria , Herpesviridae/clasificación , 2-Aminopurina/análogos & derivados , 2-Aminopurina/uso terapéutico , Animales , Antivirales/uso terapéutico , Secuencia de Bases , ADN Viral/genética , Famciclovir , Femenino , Herpesviridae/genética , Infecciones por Herpesviridae/tratamiento farmacológico , Infecciones por Herpesviridae/epidemiología , Infecciones por Herpesviridae/virología , Masculino , Texas/epidemiología , ViremiaRESUMEN
The ORF75c tegument protein of murine gammaherpesvirus 68 (MHV68) promotes the degradation of the antiviral promyelocytic leukemia (PML) protein. Surprisingly, MHV68 expressing a degradation-deficient ORF75c replicated in cell culture and in mice similar to the wild-type virus. However, in cells infected with this mutant virus, PML formed novel track-like structures that are induced by ORF61, the viral ribonucleotide reductase large subunit. These findings may explain why ORF75c mutant viruses unable to degrade PML had no demonstrable phenotype after infection.
Asunto(s)
Infecciones por Herpesviridae/veterinaria , Proteínas Nucleares/metabolismo , Rhadinovirus/enzimología , Ribonucleótido Reductasas/metabolismo , Enfermedades de los Roedores/metabolismo , Enfermedades de los Roedores/virología , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Proteínas Virales/metabolismo , Animales , Línea Celular , Infecciones por Herpesviridae/genética , Infecciones por Herpesviridae/metabolismo , Infecciones por Herpesviridae/virología , Ratones , Proteínas Nucleares/genética , Proteína de la Leucemia Promielocítica , Proteolisis , Rhadinovirus/genética , Ribonucleótido Reductasas/genética , Enfermedades de los Roedores/genética , Factores de Transcripción/genética , Proteínas Supresoras de Tumor/genética , Proteínas Virales/genéticaRESUMEN
BACKGROUND: Elephants are classified as critically endangered animals by the International Union for Conservation of Species (IUCN). Elephant endotheliotropic herpesvirus (EEHV) poses a large threat to breeding programs of captive Asian elephants by causing fatal haemorrhagic disease. EEHV infection is detected by PCR in samples from both clinically ill and asymptomatic elephants with an active infection, whereas latent carriers can be distinguished exclusively via serological assays. To date, identification of latent carriers has been challenging, since there are no serological assays capable of detecting seropositive elephants. RESULTS: Here we describe a novel ELISA that specifically detects EEHV antibodies circulating in Asian elephant plasma/serum. Approximately 80 % of PCR positive elephants display EEHV-specific antibodies. Monitoring three Asian elephant herds from European zoos revealed that the serostatus of elephants within a herd varied from non-detectable to high titers. The antibody titers showed typical herpes-like rise-and-fall patterns in time which occur in all seropositive animals in the herd more or less simultaneously. CONCLUSIONS: This study shows that the developed ELISA is suitable to detect antibodies specific to EEHV. It allows study of EEHV seroprevalence in Asian elephants. Results confirm that EEHV prevalence among Asian elephants (whether captive-born or wild-caught) is high.
Asunto(s)
Anticuerpos Antivirales/sangre , Elefantes , Ensayo de Inmunoadsorción Enzimática/veterinaria , Infecciones por Herpesviridae/veterinaria , Herpesviridae/aislamiento & purificación , Inmunoglobulina G/aislamiento & purificación , Animales , Animales de Zoológico , Clonación Molecular , Ensayo de Inmunoadsorción Enzimática/métodos , Europa (Continente)/epidemiología , Femenino , Herpesviridae/inmunología , Infecciones por Herpesviridae/diagnóstico , Infecciones por Herpesviridae/virología , Masculino , Sensibilidad y Especificidad , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/metabolismoRESUMEN
Promyelocytic leukemia protein (PML) is an essential organizer of PML nuclear bodies (NBs), which carry out a variety of activities, including antiviral functions. Herpesviruses from all subfamilies encode proteins that counteract PML NB-mediated antiviral defenses by multiple mechanisms. However, because of the species specificity of herpesviruses, only a limited number of in vivo studies have been undertaken to investigate the effect of PML or PML NBs on herpesvirus infection. To address this central issue in herpesvirus biology, we studied the course of infection in wild-type and PMLâ»/â» mice using murine gammaherpesvirus 68 (MHV68), which encodes a tegument protein that induces PML degradation. While acute infection in PMLâ»/â» mice progressed similarly to that in wild-type mice, the lytic reactivation frequency was higher in peritoneal exudate cells, due to both an increase of MHV68 genome-positive cells and greater reactivation efficiency. We also detected a higher frequency of persistent infection in PMLâ»/â» peritoneal cells. These findings suggest that the PML protein can repress the establishment or maintenance of gammaherpesvirus latency in vivo. Further use of the PMLâ»/â» mouse model should aid in dissecting the molecular mechanisms that underlie the role of PML in gammaherpesvirus latency and may yield clues for how PML modulates herpesvirus latency in general.
Asunto(s)
Embrión de Mamíferos/virología , Fibroblastos/virología , Infecciones por Herpesviridae/virología , Proteínas Nucleares/fisiología , Peritoneo/virología , Factores de Transcripción/fisiología , Proteínas Supresoras de Tumor/fisiología , Latencia del Virus , Replicación Viral , Animales , Western Blotting , Embrión de Mamíferos/metabolismo , Embrión de Mamíferos/patología , Fibroblastos/metabolismo , Fibroblastos/patología , Citometría de Flujo , Gammaherpesvirinae/patogenicidad , Regulación Viral de la Expresión Génica , Genoma Viral , Infecciones por Herpesviridae/metabolismo , Infecciones por Herpesviridae/patología , Ratones , Ratones Noqueados , Peritoneo/metabolismo , Peritoneo/patología , Proteína de la Leucemia Promielocítica , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Elephant endotheliotropic herpesvirus (EEHV) causes lethal hemorrhagic disease (HD) in Asian and African elephants. Although rapid detection of viremia and supportive treatments may improve survival rates, an effective vaccine would mitigate the devastating effects of this virus. In elephants, chronic infection with EEHV leads to adaptive immunity against glycoproteins gB and gH/gL, the core entry machinery for most herpesviruses. We previously evaluated two EEHV gB vaccines in mice but not a gH/gL vaccine. Here, we found that inoculation of mice with an adjuvanted EEHV gH/gL subunit vaccine induced a significant antibody response that was similar to the response observed in elephants chronically infected with EEHV. Moreover, the gH/gL heterodimer elicited polyfunctional T cells with a Th1 phenotype but no detectable Th2 response. These results suggest that gH/gL, possibly in combination with gB, may be suitable immunogens for a vaccine comprising herpesvirus glycoproteins that are known to mediate cell entry and infection.
RESUMEN
Infection of Asian elephants (Elephas maximus) with elephant endotheliotropic herpesvirus (EEHV) can be associated with rapid, lethal hemorrhagic disease and has been documented in elephant herds in human care and in the wild. Recent reports describe real-time quantitative polymerase chain reaction (qPCR) assays used to monitor clinically ill elephants and also to detect subclinical EEHV1 infection in apparently healthy Asian elephants. Acute phase proteins have been demonstrated to increase with a variety of infectious etiologies in domesticated mammals but have not yet been described in elephants. In addition, the immune response of Asian elephants to EEHV1 infection has not been described. In this study, whole blood and trunk wash samples representing repeated measures from eight elephants were examined for the presence of EEHV1 using a qPCR assay. Elephants were classified into groups, as follows: whole blood negative and positive and trunk wash negative and positive. Serum amyloid A (SAA) and haptoglobin (HP) levels were compared between these groups. A significant difference in SAA was observed with nearly a threefold higher mean value during periods of viremia (P=0.011). Higher values of SAA were associated with >10,000 virus genome copies/ml EEHV1 in whole blood. There were no significant differences in HP levels, although some individual animals did exhibit increased levels with infection. These data indicate that an inflammatory process is stimulated during EEHV1 viremia. Acute phase protein quantitation may aid in monitoring the health status of Asian elephants.
Asunto(s)
Proteínas de Fase Aguda/metabolismo , Elefantes/sangre , Regulación de la Expresión Génica/inmunología , Infecciones por Herpesviridae/veterinaria , Herpesviridae/clasificación , Viremia/veterinaria , Proteínas de Fase Aguda/genética , Animales , Femenino , Herpesviridae/fisiología , Infecciones por Herpesviridae/sangre , Infecciones por Herpesviridae/virología , Masculino , Viremia/virologíaRESUMEN
Elephant endotheliotropic herpesviruses (EEHVs) can cause acute hemorrhagic disease with high mortality rates in Asian elephants (Elephas maximus). Recently, a new EEHV type known as EEHV5 has been described, but its prevalence and clinical significance remain unknown. In this report, an outbreak of EEHV5 infection in a herd of captive Asian elephants in a zoo was characterized. In February 2011, a 42-yr-old wild-born female Asian elephant presented with bilaterally swollen temporal glands, oral mucosal hyperemia, vesicles on the tongue, and generalized lethargy. The elephant had a leukopenia and thrombocytopenia. She was treated with flunixin meglumine, famciclovir, and fluids. Clinical signs of illness resolved gradually over 2 wk, and the white blood cell count and platelets rebounded to higher-than-normal values. EEHV5 viremia was detectable starting 1 wk before presentation and peaked at the onset of clinical illness. EEHV5 shedding in trunk secretions peaked after viremia resolved and continued for more than 2 mo. EEHV5 trunk shedding from a female herd mate without any detectable viremia was detected prior to onset of clinical disease in the 42-yr-old elephant, indicating reactivation rather than primary infection in this elephant. Subsequent EEHV5 viremia and trunk shedding was documented in the other five elephants in the herd, who remained asymptomatic, except for 1 day of temporal gland swelling in an otherwise-healthy 1-yr-old calf. Unexpectedly, the two elephants most recently introduced into the herd 40 mo previously shed a distinctive EEHV5 strain from that seen in the other five elephants. This is the first report to document the kinetics of EEHV5 infection in captive Asian elephants and to provide evidence that this virus can cause illness in some animals.
Asunto(s)
Elefantes , Infecciones por Herpesviridae/veterinaria , Herpesviridae/clasificación , Enfermedades de la Boca/virología , Animales , Animales de Zoológico , Secuencia de Bases , ADN Viral/genética , Femenino , Infecciones por Herpesviridae/virología , Masculino , Datos de Secuencia Molecular , Viremia , Esparcimiento de VirusRESUMEN
Elephant endotheliotropic herpesviruses (EEHVs) can cause fatal hemorrhagic disease in juvenile Asian elephants (Elphas maximus); however, sporadic shedding of virus in trunk washes collected from healthy elephants also has been detected. Data regarding the relationship of viral loads in blood compared with trunk washes are lacking, and questions about whether elephants can undergo multiple infections with EEHVs have not been addressed previously. Real-time quantitative polymerase chain reaction was used to determine the kinetics of EEHV1 loads, and genotypic analysis was performed on EEHV1 DNA detected in various fluid samples obtained from five Asian elephants that survived detectable EEHV1 DNAemia on at least two separate occasions. In three elephants displaying clinical signs of illness, preclinical EEHV1 DNAemia was detectable, and peak whole-blood viral loads occurred 3-8 days after the onset of clinical signs. In two elephants with EEHV1 DNAemia that persisted for 7-21 days, no clinical signs of illness were observed. Detection of EEHV1 DNA in trunk washes peaked approximately 21 days after DNAemia, and viral genotypes detected during DNAemia matched those detected in subsequent trunk washes from the same elephant. In each of the five elephants, two distinct EEHV1 genotypes were identified in whole blood and trunk washes at different time points. In each case, these genotypes represented both an EEHV1A and an EEHV1B subtype. These data suggest that knowledge of viral loads could be useful for the management of elephants before or during clinical illness. Furthermore, sequential infection with both EEHV1 subtypes occurs in Asian elephants, suggesting that they do not elicit cross-protective sterilizing immunity. These data will be useful to individuals involved in the husbandry and clinical care of Asian elephants.
Asunto(s)
Elefantes , Genotipo , Infecciones por Herpesviridae/veterinaria , Varicellovirus/clasificación , Varicellovirus/genética , Carga Viral , Animales , Animales de Zoológico , Femenino , Infecciones por Herpesviridae/virología , Masculino , Filogenia , Embarazo , Factores de TiempoRESUMEN
The interferon-inducible Sp100 proteins are thought to play roles in the chromatin pathway and in transcriptional regulation. Sp100A, the smallest isoform, is one of the major components of PML nuclear bodies (NBs) that exhibit intrinsic antiviral activity against several viruses. Since PML NBs are disrupted by the immediate-early 1 (IE1) protein during human cytomegalovirus (HCMV) infection, the modulation of Sp100 protein expression or activity during infection has been suggested. Here, we show that Sp100 proteins are lost largely in the late stages of HCMV infection. This event required viral gene expression and involved posttranscriptional control. The mutant virus with deletion of the sequence for IE1 (CR208) did not have Sp100 loss. In CR208 infection, PML depletion by RNA interference abrogated the accumulation of SUMO-modified Sp100A and of certain high-molecular-weight Sp100 isoforms but did not significantly affect unmodified Sp100A, suggesting that the IE1-induced disruption of PML NBs is not sufficient for the complete loss of Sp100 proteins. Sp100A loss was found to require proteasome activity. Depletion of all Sp100 proteins by RNA silencing enhanced HCMV replication and major IE (MIE) gene expression. Sp100 knockdown enhanced the acetylation level of histones associated with the MIE promoter, demonstrating that the repressive effect of Sp100 proteins may involve, at least in part, the epigenetic control of the MIE promoter. Sp100A was found to interact directly with IE1 through the N-terminal dimerization domain. These findings indicate that the IE1-dependent loss of Sp100 proteins during HCMV infection may represent an important requirement for efficient viral growth.
Asunto(s)
Antígenos Nucleares/metabolismo , Autoantígenos/metabolismo , Citomegalovirus/patogenicidad , Expresión Génica , Interacciones Huésped-Patógeno , Proteínas Inmediatas-Precoces/metabolismo , Replicación Viral , Células Cultivadas , Citomegalovirus/crecimiento & desarrollo , Silenciador del Gen , HumanosRESUMEN
BACKGROUND: Socioeconomic conditions may strongly influence the risk of stroke. We tested the hypotheses that indexes of social status in different life periods including childhood are inversely associated with stroke risk and that there is a cumulative effect of social conditions during lifetime on the risk of stroke. Furthermore, we investigated whether social advancement compared to the parental generation is associated with reduced stroke risk. METHODS: In a case-control study, we assessed parental professional status, highest school degree, professional education and the last professional activity in 370 consecutive patients with ischemic or hemorrhagic stroke or transient ischemic attack [TIA; age 60.7 ± 12.8 years (mean ± standard deviation); 31.1% women] and 370 age- and sex-matched control subjects randomly selected from the general population of the same area. RESULTS: Higher level of school exams [odds ratio (OR) 0.58, 95% confidence interval (CI) 0.39-0.86], university or polytechnic high school degrees (OR 0.39, 95% CI 0.24-0.63), nonmanual (last or current) professional activity (OR 0.51, 95% CI 0.37-0.71) and father's nonmanual professional activity (OR 0.64, 95% 0.43-0.97) were associated with a lower risk of stroke/TIA. Adjustment for vascular risk factors including current smoking and alcohol consumption reduced the strength of these associations and rendered them nonsignificant except for university or polytechnic high school degrees (OR 0.49, 95% CI 0.27-0.87). Additional adjustment for regular sports activity further attenuated the association between academic degrees and risk of stroke/TIA (OR 0.56, 95% CI 0.31-1.02). A score summarizing 4 lifetime social indexes was not independently associated with stroke risk (OR 0.67, 95% CI 0.39-1.16). Social advancement as assessed by changes from paternal manual work to nonmanual work in the index generation was more common among control subjects (23.5%) than patients (15.3%; p = 0.0097), but such advancement was not independently associated with stroke/TIA after adjustment for all covariables (OR 0.82, 95% CI 0.50-1.33). CONCLUSIONS: Socioeconomic conditions were inversely linked to the risk of stroke/TIA. These associations were strongly influenced by lifestyle factors such as smoking, alcohol consumption and mainly sports activity. Stroke preventive strategies may have a particularly large potential if they focus on such lifestyle habits in socially disadvantaged groups.
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Condiciones Sociales , Accidente Cerebrovascular/epidemiología , Adulto , Factores de Edad , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Estudios de Casos y Controles , Niño , Intervalos de Confianza , Escolaridad , Empleo , Familia , Femenino , Humanos , Ataque Isquémico Transitorio/epidemiología , Estilo de Vida , Masculino , Estado Civil , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , Factores Sexuales , Fumar/efectos adversos , Fumar/epidemiología , Factores Socioeconómicos , DeportesRESUMEN
BACKGROUND: A considerable number of patients with severely elevated LDL-C do not achieve recommended treatment targets, despite treatment with statins. Adults at high cardiovascular risk with hypercholesterolemia and LDL-C ≥ 2.59 and ≤ 4.14 mmol/L (N = 250), pretreated with atorvastatin 20 mg were randomized to ezetimibe/simvastatin 10/40 mg or atorvastatin 40 mg for 6 weeks. The percent change in LDL-C and other lipids was assessed using a constrained longitudinal data analysis method with terms for treatment, time, time-by-treatment interaction, stratum, and time-by-stratum interaction. Percentage of subjects achieving LDL-C < 1.81 mmol/L, < 2.00 mmol/L, or < 2.59 mmol/L was assessed using a logistic regression model with terms for treatment and stratum. Tolerability was assessed. RESULTS: Switching to ezetimibe/simvastatin resulted in significantly greater changes in LDL-C (-26.81% vs.-11.81%), total cholesterol (-15.97% vs.-7.73%), non-HDL-C (-22.50% vs.-10.88%), Apo B (-17.23% vs.-9.53%), and Apo A-I (2.56% vs.-2.69%) vs. doubling the atorvastatin dose (all p ≤ 0.002), but not HDL-C, triglycerides, or hs-CRP. Significantly more subjects achieved LDL-C < 1.81 mmol/L (29% vs. 5%), < 2.00 mmol/L (38% vs. 9%) or < 2.59 mmol/L (69% vs. 41%) after switching to ezetimibe/simvastatin vs. doubling the atorvastatin dose (all p < 0.001). The overall safety profile appeared generally comparable between treatment groups. CONCLUSIONS: In high cardiovascular risk subjects with hypercholesterolemia already treated with atorvastatin 20 mg but not at LDL-C < 2.59 mmol/L, switching to combination ezetimibe/simvastatin 10/40 mg provided significantly greater LDL-C lowering and greater achievement of LDL-C targets compared with doubling the atorvastatin dose to 40 mg. Both treatments were generally well-tolerated. TRIAL REGISTRATION: Registered at clinicaltrials.gov: NCT00782184.