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1.
Vox Sang ; 119(7): 675-685, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38596985

RESUMEN

BACKGROUND AND OBJECTIVES: Antibodies to human leucocyte antigen (HLA) Class-I antigens can lead to refractoriness to platelet transfusion. Although this can be overcome by transfusion of HLA-compatible platelets, they are not always available. Disruption of HLA antigens on platelets by acid treatment may be a suitable alternative when no other components are available. The aim of this study was to assess the effect of HLA disruption and subsequent storage of platelet components. MATERIALS AND METHODS: Platelet components were treated with 0.9% saline or citric acid solution (pH 3.0), and then stored until expiry (Day 7). HLA and platelet glycoprotein expression, platelet viability, activation and sialylation were measured by flow cytometry. Release of soluble factors was measured by ELISA and metabolism by biochemistry analyser. Reactivity to patient anti-sera containing anti-HLA antibodies was measured using platelet immunofluorescence tests (PIFTs) and monoclonal antibody immobilization of platelet antigen (MAIPA) assays. Platelet function was measured using aggregometry and thromboelastography (TEG). RESULTS: Acid treatment reduced detection of HLA Class-I on platelets by 75%, with significant reductions in reactivity to patient anti-sera. Acid treatment reduced platelet content and viability, increased platelet activation and accelerated metabolism. Glycan cleavage was increased by acid treatment. Treatment reduced platelet activation following agonist stimulation by ADP and TRAP-6, but platelets remained functional, displaying increased aggregation response and reduced time to clot formation by TEG. CONCLUSION: Although HLA disruption had some detrimental effects, acid-treated platelets remained functional, retaining their capacity to respond to agonists and form clots, and with further development could be used to support refractory patients.


Asunto(s)
Plaquetas , Conservación de la Sangre , Humanos , Plaquetas/metabolismo , Plaquetas/inmunología , Conservación de la Sangre/métodos , Antígenos HLA/inmunología , Activación Plaquetaria/efectos de los fármacos , Transfusión de Plaquetas
2.
Proc Biol Sci ; 289(1969): 20212087, 2022 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-35193398

RESUMEN

Predicting pathogen emergence and spillover risk requires understanding the determinants of a pathogens' host range and the traits involved in host competence. While host competence is often considered a fixed species-specific trait, it may be variable if pathogens diversify across hosts. Balancing selection can lead to maintenance of pathogen polymorphisms (multiple-niche-polymorphism; MNP). The causative agent of Lyme disease, Borrelia burgdorferi (Bb), provides a model to study the evolution of host adaptation, as some Bb strains defined by their outer surface protein C (ospC) genotype, are widespread in white-footed mice and others are associated with non-rodent vertebrates (e.g. birds). To identify the mechanisms underlying potential strain × host adaptation, we infected American robins and white-footed mice, with three Bb strains of different ospC genotypes. Bb burdens varied by strain in a host-dependent fashion, and strain persistence in hosts largely corresponded to Bb survival at early infection stages and with transmission to larvae (i.e. fitness). Early survival phenotypes are associated with cell adhesion, complement evasion and/or inflammatory and antibody-mediated removal of Bb, suggesting directional selective pressure for host adaptation and the potential role of MNP in maintaining OspC diversity. Our findings will guide future investigations to inform eco-evolutionary models of host adaptation for microparasites.


Asunto(s)
Grupo Borrelia Burgdorferi , Borrelia burgdorferi , Enfermedad de Lyme , Animales , Borrelia burgdorferi/genética , Grupo Borrelia Burgdorferi/genética , Adaptación al Huésped , Peromyscus , Fenotipo
3.
Transfusion ; 62(2): 273-278, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34761380

RESUMEN

BACKGROUND: Platelet collection and processing methods, as well as donor attributes, can influence platelet function and quality during ex vivo storage. In this study, activation and procoagulant responses in platelets collected from donors experiencing a citrate reaction (CR) were investigated. STUDY DESIGN AND METHODS: Apheresis platelet components (n = 54) were stored in 100% autologous plasma and tested on days 1 and 5 post-collection. Platelet components were categorized into two groups according to whether the donor had experienced a CR during donation (n = 10; non-CR group, n = 44). Platelet aggregation was initiated with collagen and thrombin. Platelet phenotype was characterized by flow cytometry. Fibrinogen binding was assessed following collagen + thrombin stimulation (COATed platelets), and procoagulant activity was assessed using a procoagulant phospholipid assay (PPL). Platelet microparticle (PMP) subsets were enumerated by flow cytometry. RESULTS: Basal von Willebrand factor (VWF) binding was higher in the CR donations when compared with the non-CR group. Collagen aggregation was significantly higher in platelets from CR donations, in contrast to aggregation induced by thrombin. The proportion of phosphatidylserine (PS) positive PMP and PPL clotting time were higher in the CR group, in contrast to the number of basal PS+ platelets and COATed platelets following stimulation. CONCLUSION: Platelets donated by donors who experienced a CR during donation had higher platelet activation response and possibly a more procoagulant PMP phenotype, suggesting that this donor reaction might lead to increased platelet activation.


Asunto(s)
Eliminación de Componentes Sanguíneos , Plaquetas , Plaquetas/metabolismo , Citratos , Ácido Cítrico/metabolismo , Ácido Cítrico/farmacología , Colágeno/metabolismo , Colágeno/farmacología , Humanos , Fenotipo , Fosfatidilserinas/metabolismo , Activación Plaquetaria , Trombina/análisis
4.
Transfusion ; 61(11): 3081-3086, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34554562

RESUMEN

BACKGROUND: Irradiation of selected blood components is standard practice for the prevention of transfusion-associated graft-versus-host disease (TA-GvHD). Currently, gamma-irradiation is the most widely used form of irradiation, but there is an increasing interest in X-irradiation, which is considered to be functionally equivalent and safer. However, there is a paucity of contemporary data regarding the ability of X-irradiation to inactivate lymphocytes in blood components. Therefore, the effect of gamma- and X-irradiation on lymphocyte viability and function in blood components was compared. STUDY DESIGN AND METHODS: Lymphocytes were isolated from venous blood by density gradient centrifugation, spiked into plasma/SSP+ to simulate a blood component, and either gamma- or X-irradiated. The phenotype of the isolated lymphocytes was confirmed. Lymphocyte viability was measured using a LIVE/DEAD assay, and function was assessed using mixed lymphocyte culture and CD69 expression post-phorbol-12 myristate 13-acetate (PMA) stimulation. RESULTS: Lymphocyte viability and CD69 expression following PMA stimulation were significantly reduced by both gamma-irradiation and X-irradiation in simulated blood components. Allorecognition and allostimulation were also significantly reduced by both gamma-irradiation and X-irradiation. CONCLUSION: Lymphocyte viability and function are reduced to a similar extent by gamma- and X-irradiation in simulated blood components. As such, X-irradiation is suitable for the irradiation of blood components and, in terms of lymphocyte inactivation, could be used instead of gamma-irradiation.


Asunto(s)
Enfermedad Injerto contra Huésped , Reacción a la Transfusión , Transfusión de Componentes Sanguíneos , Rayos gamma , Enfermedad Injerto contra Huésped/prevención & control , Humanos , Linfocitos/efectos de la radiación
5.
Emerg Infect Dis ; 26(6): 1315-1319, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32441636

RESUMEN

During 2016-2017, three rabid terrestrial animals were discovered in the raccoon rabies virus-free zone of Long Island, New York, USA. Whole-genome sequencing and phylogenetic analyses revealed the likely origins of the viruses, enabling the rabies outbreak response (often costly and time-consuming) to be done less expensively and more efficiently.


Asunto(s)
Vacunas Antirrábicas , Virus de la Rabia , Rabia , Animales , Animales Salvajes , New York/epidemiología , Filogenia , Rabia/epidemiología , Rabia/veterinaria , Virus de la Rabia/genética , Mapaches , Zoonosis
6.
Haematologica ; 105(4): 1081-1094, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31273092

RESUMEN

Upon vascular injury, platelets adhere to von Willebrand Factor (VWF) via glycoprotein Ibα (GPIbα). GPIbα contains many glycans, capped by sialic acid. Sialic acid cleavage (desialylation) triggers clearance of platelets. Neuraminidases (NEU) are responsible for desialylation and so far, NEU1-4 have been identified. However, the role of NEU in healthy platelets is currently unknown. Aim of the study was to study the role of NEU1 and NEU2 in platelet signalling. Membrane association of platelet attached glycans, NEU1 and NEU2 was measured following activation with agonists using flow cytometry. Adhesion on fibrinogen, aggregation and fibrinogen-binding were assessed with/without the NEU-inhibitor, 2-deoxy-2-3-dide-hydro-N-acetylneuraminic acid. Cellular localisation of NEU1 and NEU2 was examined by fluorescence microscopy. Desialylation occurred following GPIbα-clustering by VWF. Basal levels of membrane NEU1 were low; glycoprotein Ibα-clustering induced a four-fold increase (n=3, P<0.05). Inhibition of αIIbß3-integrin prevented the increase in NEU1 membrane-association by ~60%. Membrane associated NEU2 increased two-fold (n=3, P<0.05) upon VWF-binding, while inhibition/removal of GPIbα reduced the majority of membrane associated NEU1 and NEU2 (n=3, P<0.05). High shear and addition of fibrinogen increased membrane NEU1 and NEU2. NEU-inhibitior prevented VWF-induced αIIbß3-integrin activation by 50% (n=3, P<0.05), however, promoted VWF-mediated agglutination, indicating a negative feedback mechanism for NEU activity. NEU1 or NEU2 were partially co-localised with mitochondria and α-granules respectively. Neither NEU1 nor NEU2 co-localised with lysosomal-associated membrane protein 1. These findings demonstrate a previously unrecognised role for NEU1 and NEU2 in GPIbα-mediated and αIIbß3-integrin signalling.


Asunto(s)
Neuraminidasa , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria , Plaquetas , Humanos , Complejo GPIb-IX de Glicoproteína Plaquetaria , Transducción de Señal , Factor de von Willebrand
7.
Mol Cell ; 47(4): 570-84, 2012 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-22819326

RESUMEN

Although inactivation of the PTEN gene has been implicated in the development of resistance to the HER2 targeting antibody trastuzumab, the mechanisms mediating this resistance remain elusive. We generated trastuzumab resistant cells by knocking down PTEN expression in HER2 overexpressing breast cancer cell lines and demonstrate that development of trastuzumab resistance in these cells is mediated by activation of an IL6 inflammatory feedback loop leading to expansion of the cancer stem cell (CSC) population. Long term trastuzumab treatment generates highly enriched CSCs which display an EMT phenotype secreting over 100-fold more IL6 than parental cells. An IL6 receptor antibody interrupted this inflammatory feedback loop reducing the cancer stem cell population resulting in decreased tumor growth and metastasis in mouse xenographs. These studies demonstrate that trastuzumab resistance may be mediated by an IL6 inflammatory loop and suggest that blocking this loop may provide alternative strategy to overcome trastuzumab resistance.


Asunto(s)
Anticuerpos Monoclonales Humanizados/farmacología , Neoplasias de la Mama/metabolismo , Inflamación/metabolismo , Interleucina-6/metabolismo , Células Madre Neoplásicas/metabolismo , Receptor ErbB-2/metabolismo , Animales , Antineoplásicos/farmacología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Regulación hacia Abajo/genética , Resistencia a Antineoplásicos , Femenino , Humanos , Inflamación/genética , Inflamación/patología , Interleucina-6/genética , Interleucina-8/genética , Interleucina-8/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , Células Madre Neoplásicas/patología , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Receptor ErbB-2/genética , Trastuzumab
9.
Front Zool ; 16: 40, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31827569

RESUMEN

BACKGROUND: White-nose Syndrome (WNS) is a mycosis caused by a cutaneous infection with the fungus Pseudogymnoascus destructans (Pd). It produces hibernation mortality rates of 75-98% in 4 bats: Myotis lucifugus, M. septentrionalis, M. sodalis, and Perimyotis subflavus. These high mortality rates were observed during the first several years after the arrival of P. destructans at a hibernation site. Mortality is caused by a 60% decrease in torpor bout duration, which results in a premature depletion of depot fat prior to spring. RESULTS: Little is known about the long-term effects of Pd on torpor and mortality, thus we conducted a 9-year study on M. lucifugus at 5 of the hibernation sites where Pd first appeared in North America during the winter of 2007-08. The M. lucifugus hibernating at one of these sites one year after the arrival of Pd (2008-09) had: a) a mean torpor bout duration of 7.6 d, b) no depot fat reserves by March, and c) an apparent over-winter mortality rate of 88%. The M. lucifugus hibernating at this same site 6-9 years after the arrival of Pd, in contrast, had: a) a mean torpor bout duration of 14.7 d, b) depot fat remaining in March, and c) an apparent mortality rate of 50%. The number of M. lucifugus hibernating at 2 of these sites has consistently increased since 2010 and is now more than 3.0-fold higher than the number remaining after the winter of 2008-09. CONCLUSIONS: These findings indicate that this population of M. lucifugus has evolved mechanisms to hibernate well in the presence of Pd, thus reducing over-winter mortality.

10.
J Virol ; 90(4): 2102-11, 2016 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-26656703

RESUMEN

UNLABELLED: The alphaherpesviral envelope protein pUS9 has been shown to play a role in the anterograde axonal transport of herpes simplex virus 1 (HSV-1), yet the molecular mechanism is unknown. To address this, we used an in vitro pulldown assay to define a series of five arginine residues within the conserved pUS9 basic domain that were essential for binding the molecular motor kinesin-1. The mutation of these pUS9 arginine residues to asparagine blocked the binding of both recombinant and native kinesin-1. We next generated HSV-1 with the same pUS9 arginine residues mutated to asparagine (HSV-1pUS9KBDM) and then restored them being to arginine (HSV-1pUS9KBDR). The two mutated viruses were analyzed initially in a zosteriform model of recurrent cutaneous infection. The primary skin lesion scores were identical in severity and kinetics, and there were no differences in viral load at dorsal root ganglionic (DRG) neurons at day 4 postinfection (p.i.) for both viruses. In contrast, HSV-1pUS9KBDM showed a partial reduction in secondary skin lesions at day 8 p.i. compared to the level for HSV-1pUS9KBDR. The use of rat DRG neuronal cultures in a microfluidic chamber system showed both a reduction in anterograde axonal transport and spread from axons to nonneuronal cells for HSV-1pUS9KBDM. Therefore, the basic domain of pUS9 contributes to anterograde axonal transport and spread of HSV-1 from neurons to the skin through recruitment of kinesin-1. IMPORTANCE: Herpes simplex virus 1 and 2 cause genital herpes, blindness, encephalitis, and occasionally neonatal deaths. There is also increasing evidence that sexually transmitted genital herpes increases HIV acquisition, and the reactivation of HSV increases HIV replication and transmission. New antiviral strategies are required to control resistant viruses and to block HSV spread, thereby reducing HIV acquisition and transmission. These aims will be facilitated through understanding how HSV is transported down nerves and into skin. In this study, we have defined how a key viral protein plays a role in both axonal transport and spread of the virus from nerve cells to the skin.


Asunto(s)
Transporte Axonal , Herpesvirus Humano 1/fisiología , Interacciones Huésped-Patógeno , Cinesinas/metabolismo , Lipoproteínas/metabolismo , Neuronas/virología , Fosfoproteínas/metabolismo , Proteínas Virales/metabolismo , Liberación del Virus , Secuencia de Aminoácidos , Animales , Sitios de Unión , Técnicas Citológicas , Análisis Mutacional de ADN , Modelos Animales de Enfermedad , Femenino , Ganglios Espinales/virología , Herpes Simple/patología , Herpes Simple/virología , Herpesvirus Humano 1/genética , Humanos , Péptidos y Proteínas de Señalización Intracelular , Lipoproteínas/genética , Ratones Endogámicos C57BL , Modelos Biológicos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Fosfoproteínas/genética , Unión Proteica , Mapeo de Interacción de Proteínas , Ratas Wistar , Índice de Severidad de la Enfermedad , Piel/patología , Piel/virología , Carga Viral , Proteínas Virales/genética
11.
Transfusion ; 56(7): 1807-18, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27158813

RESUMEN

BACKGROUND: Alternatives to room temperature storage of platelets (PLTs) may be beneficial to extend the limited shelf life and support transfusion logistics in rural and military areas. The aim of this study was to assess the morphologic, metabolic, and functional aspects of PLTs stored at room temperature or in refrigerated conditions or cryopreserved. STUDY DESIGN AND METHODS: A three-arm pool-and-split study was carried out using buffy coat-derived PLTs stored in 30% plasma/70% SSP+. The three matched treatment arms were room temperature stored (20-24°C), cold-stored (2-6°C), and cryopreserved (-80°C with dimethyl sulfoxide). Liquid-stored PLTs were tested over a 21-day period, while cryopreserved PLTs were examined immediately after thawing and after 6 and 24 hours of storage at room temperature. RESULTS: Cold-stored and cryopreserved PLTs underwent a significant shape change, although the cryopreserved PLTs appeared to recover from this during subsequent storage. Glycolytic metabolism was reduced in cold-stored PLTs, but accelerated in cryopreserved PLTs, while oxidative phosphorylation was negatively affected by both storage conditions. PLT aggregation was potentiated by cold storage and diminished by cryopreservation in comparison to room temperature-stored PLTs. Cold storage and cryopreservation resulted in faster clot formation (R-time; thromboelastography), which was associated with an increase in microparticles. CONCLUSION: Cold storage and cryopreservation of PLTs led to morphologic and metabolic changes. However, storage under these conditions appears to maintain or even enhance certain aspects of in vitro PLT function.


Asunto(s)
Plaquetas/metabolismo , Conservación de la Sangre/métodos , Criopreservación , Refrigeración , Plaquetas/fisiología , Seguridad de la Sangre , Micropartículas Derivadas de Células , Glucólisis , Humanos , Fosforilación Oxidativa , Pruebas de Función Plaquetaria , Factores de Tiempo
12.
J Clin Microbiol ; 53(9): 2983-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26179300

RESUMEN

Rabies virus found worldwide and prevalent throughout the United States continues to be a public health concern. Direct-fluorescent antibody (DFA) detection remains the gold standard for rabies virus diagnostics. Assessing the utility of a high-throughput molecular platform such as the QIAsymphony SP/AS, in conjunction with quantitative reverse transcription-PCR (qRT-PCR), to augment or potentially replace the DFA test, was the focus of this project. Here we describe a triplex qRT-PCR assay, including assembly and evaluation for sensitivity, specificity, and ability to detect variants. Additionally, we compared the qRT-PCR assay to the gold standard direct fluorescent-antibody test. More than 1,000 specimens submitted for routine rabies diagnosis were tested to directly compare the two methods. All results were in agreement between the two methods, with one additional specimen detected by qRT-PCR below the limits of the DFA sensitivity. With the proper continued validation for variant detection, molecular methods have a place in routine rabies diagnostics within the United States.


Asunto(s)
Anticuerpos Antivirales/sangre , Técnica del Anticuerpo Fluorescente Directa/métodos , ARN Viral/análisis , Rabia/diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Animales , Encéfalo/virología , Humanos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Sensibilidad y Especificidad , Estados Unidos
13.
J Virol ; 87(16): 9008-15, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23741002

RESUMEN

Rabies virus (RABV) maintenance in bats is not well understood. Big brown bats (Eptesicus fuscus), little brown bats (Myotis lucifugus), and Mexican free-tailed bats (Tadarida brasiliensis) are the most common bats species in the United States. These colonial bat species also have the most frequent contact with humans and domestic animals. However, the silver-haired bat (Lasionycteris noctivagans) RABV is associated with the majority of human rabies virus infections in the United States and Canada. This is of interest because silver-haired bats are more solitary bats with infrequent human interaction. Our goal was to determine the likelihood of a colonial bat species becoming infected with and transmitting a heterologous RABV. To ascertain the potential of heterologous RABV infection in colonial bat species, little brown bats were inoculated with a homologous RABV or one of two heterologous RABVs. Additionally, to determine if the route of exposure influenced the disease process, bats were inoculated either intramuscularly (i.m.) or subcutaneously (s.c.) with a homologous or heterologous RABV. Our results demonstrate that intramuscular inoculation results in a more rapid progression of disease onset, whereas the incubation time in bats inoculated s.c. is significantly longer. Additionally, cross protection was not consistently achieved in bats previously inoculated with a heterologous RABV following a challenge with a homologous RABV 6 months later. Finally, bats that developed rabies following s.c. inoculation were significantly more likely to shed virus in their saliva and demonstrated increased viral dissemination. In summary, bats inoculated via the s.c. route are more likely to shed virus, thus increasing the likelihood of transmission.


Asunto(s)
Virus de la Rabia/patogenicidad , Rabia/veterinaria , Animales , Quirópteros , Susceptibilidad a Enfermedades , Rabia/patología , Rabia/transmisión , Rabia/virología , Virus de la Rabia/inmunología , Esparcimiento de Virus
14.
J Vis Exp ; (203)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38314801

RESUMEN

The rabies indirect fluorescent antibody (IFA) test was developed to detect various rabies-specific antibody isotypes in sera or cerebral spinal fluid. This test provides rapid results and can be used to detect rabies antibodies in several different scenarios. The rabies IFA test is especially useful for the quick and early detection of antibodies to evaluate the immune response in a patient who has developed rabies. Although other methods for antemortem rabies diagnosis take precedence, this test may be utilized to demonstrate recent rabies virus exposure through antibody detection. The IFA test does not provide a virus-neutralizing antibody (VNA) titer, but the pre-exposure prophylaxis (PrEP) response can be evaluated through positive or negative antibody presence. This test can be utilized in various situations and can provide results for a number of different targets. In this study, we used several paired serum samples from individuals who received PrEP and demonstrated their rabies antibody presence over time using the IFA test.


Asunto(s)
Virus de la Rabia , Rabia , Humanos , Inmunoglobulina M , Anticuerpos Antivirales , Inmunoglobulina G
15.
Vector Borne Zoonotic Dis ; 24(8): 552-562, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38775097

RESUMEN

Background: Throughout the Americas, Lyssavirus rabies (RV) perpetuates as multiple variants among bat and mesocarnivore species. Interspecific RV spillover occurs on occasion, but clusters and viral host shifts are rare. The spillover and host shift of a big brown bat (Eptesicus fuscus) RV variant Ef-W1 into mesocarnivores was reported previously on several occasions during 2001-2009 in Flagstaff, Arizona, USA, and controlled through rabies vaccination of target wildlife. During autumn 2021, a new cluster of Ef-W1 RV cases infecting striped skunks (Mephitis mephitis) was detected from United States Department of Agriculture enhanced rabies surveillance in Flagstaff. The number of Ef-W1 RV spillover cases within a short timeframe suggested the potential for transmission between skunks and an emerging host shift. Materials and Methods: Whole and partial RV genomic sequencing was performed to evaluate the phylogenetic relationships of the 2021-2023 Ef-W1 cases infecting striped skunks with earlier outbreaks. Additionally, real-time reverse-transcriptase PCR (rtRT-PCR) was used to opportunistically compare viral RNA loads in brain and salivary gland tissues of naturally infected skunks. Results: Genomic RV sequencing revealed that the origin of the 2021-2023 epizootic of Ef-W1 RV was distinct from the multiple outbreaks detected from 2001-2009. Naturally infected skunks with the Ef-W1 RV showed greater viral RNA loads in the brain, but equivalent viral RNA loads in the mandibular salivary glands, compared to an opportunistic sample of skunks naturally infected with a South-Central skunk RV from northern Colorado, USA. Conclusion: Considering a high risk for onward transmission and spread of the Ef-W1 RV in Flagstaff, public outreach, enhanced rabies surveillance, and control efforts, focused on education, sample characterization, and vaccination, have been ongoing since 2021 to mitigate and prevent the spread and establishment of Ef-W1 RV in mesocarnivores.


Asunto(s)
Quirópteros , Mephitidae , Filogenia , Rabia , Animales , Arizona/epidemiología , Mephitidae/virología , Rabia/epidemiología , Rabia/veterinaria , Rabia/virología , Quirópteros/virología , Virus de la Rabia/genética , Virus de la Rabia/clasificación , Virus de la Rabia/aislamiento & purificación , Lyssavirus/genética , Lyssavirus/clasificación , Lyssavirus/aislamiento & purificación , Enfermedades Transmisibles Emergentes/virología , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/veterinaria , Genoma Viral
16.
Arch Virol ; 158(4): 809-20, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23208279

RESUMEN

Rabies virus infection has been documented in several North American bat species, including Eptesicus fuscus. The virus-host relationship between bats and rabies virus (RV) is not well understood. The incidence of non-lethal RV exposure, based on the presence of viral neutralizing antibodies, demonstrates that exposure to RV does not always lead to clinical infection in bats. It is unknown how the route of exposure, rabies virus variant, or health of the bat affects the outcome following exposure. This paper describes the pathogenesis of two big brown bat RV variants in homologous host species. Our study demonstrates that RV variants obtained from the same species of bat from similar geographical areas may result in a diverse clinical progression of disease.


Asunto(s)
Quirópteros/virología , Virus de la Rabia/genética , Virus de la Rabia/fisiología , Rabia/veterinaria , Secuencia de Aminoácidos , Animales , ADN Complementario/genética , ADN Viral/genética , Regulación Viral de la Expresión Génica , Ratones , Ratones Endogámicos ICR , Datos de Secuencia Molecular , Rabia/virología , Virus de la Rabia/clasificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Virales/genética , Proteínas Virales/metabolismo
17.
J Wildl Dis ; 59(2): 310-314, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37074768

RESUMEN

Canine distemper virus (also known as Canine morbillivirus), the etiologic agent of canine distemper, is a highly contagious pathogen causing a multisystemic infection in carnivores globally. Canine distemper may be clinically indistinguishable from rabies, and outbreaks of either disease are major concerns. In the US, both diseases are endemic and managed by parenteral vaccination in domestic animals. In wildlife, oral vaccination and trap-vaccinate-release programs are available for rabies prevention, but no such strategies exist for canine distemper. We evaluated the prevalence at which canine distemper virus occurred concurrently in animals infected with rabies virus. Real-time quantitative reverse transcriptase PCR (qRT-PCR) was performed on specimens previously diagnosed with rabies during 2017-19 by the New York State Rabies Laboratory. Real-time qRT-PCR detected concurrent canine distemper virus infection in 73 of 1,302 animals with rabies virus. Coinfection rates were approximately 9% in Procyon lotor, 2% in Vulpes vulpes, and 0.4% in Mephitis mephitis, with an overall prevalence of 5.6%. As comorbidities in wildlife occur, laboratory-based surveillance and confirmatory testing are critical to rapid decision making for disease prevention. Rabies virus incursions are expensive and difficult to manage, and spillover events create health risks to humans and domestic animals as well as to free-roaming wildlife.


Asunto(s)
Carnívoros , Coinfección , Virus del Moquillo Canino , Moquillo , Enfermedades de los Perros , Virus de la Rabia , Rabia , Animales , Perros , Humanos , Animales Salvajes , Rabia/epidemiología , Rabia/veterinaria , Rabia/prevención & control , Mephitidae , Moquillo/complicaciones , Moquillo/epidemiología , Coinfección/veterinaria , Animales Domésticos , Mapaches , Zorros
18.
mSystems ; 7(4): e0048822, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-35938719

RESUMEN

Host association-the selective adaptation of pathogens to specific host species-evolves through constant interactions between host and pathogens, leaving a lot yet to be discovered on immunological mechanisms and genomic determinants. The causative agents of Lyme disease (LD) are spirochete bacteria composed of multiple species of the Borrelia burgdorferi sensu lato complex, including B. burgdorferi (Bb), the main LD pathogen in North America-a useful model for the study of mechanisms underlying host-pathogen association. Host adaptation requires pathogens' ability to evade host immune responses, such as complement, the first-line innate immune defense mechanism. We tested the hypothesis that different host-adapted phenotypes among Bb strains are linked to polymorphic loci that confer complement evasion traits in a host-specific manner. We first examined the survivability of 20 Bb strains in sera in vitro and/or bloodstream and tissues in vivo from rodent and avian LD models. Three groups of complement-dependent host-association phenotypes emerged. We analyzed complement-evasion genes, identified a priori among all strains and sequenced and compared genomes for individual strains representing each phenotype. The evolutionary history of ospC loci is correlated with host-specific complement-evasion phenotypes, while comparative genomics suggests that several gene families and loci are potentially involved in host association. This multidisciplinary work provides novel insights into the functional evolution of host-adapted phenotypes, building a foundation for further investigation of the immunological and genomic determinants of host association. IMPORTANCE Host association is the phenotype that is commonly found in many pathogens that preferential survive in particular hosts. The Lyme disease (LD)-causing agent, B. burgdorferi (Bb), is an ideal model to study host association, as Bb is mainly maintained in nature through rodent and avian hosts. A widespread yet untested concept posits that host association in Bb strains is linked to Bb functional genetic variation conferring evasion to complement, an innate defense mechanism in vertebrate sera. Here, we tested this concept by grouping 20 Bb strains into three complement-dependent host-association phenotypes based on their survivability in sera and/or bloodstream and distal tissues in rodent and avian LD models. Phylogenomic analysis of these strains further correlated several gene families and loci, including ospC, with host-specific complement-evasion phenotypes. Such multifaceted studies thus pave the road to further identify the determinants of host association, providing mechanistic insights into host-pathogen interaction.


Asunto(s)
Borrelia burgdorferi , Borrelia , Enfermedad de Lyme , Humanos , Filogenia , Enfermedad de Lyme/genética , Borrelia burgdorferi/genética , Proteínas del Sistema Complemento/genética
19.
Mycopathologia ; 172(4): 247-56, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21706286

RESUMEN

Geomyces destructans is the etiologic agent of bat geomycosis, commonly referred to as white nose syndrome (WNS). This infection has caused severe morbidity and mortality in little brown bats (Myotis lucifugus) and has also spread to other bat species with significant decline in the populations. Currently, G. destructans infection is identified by culture, ITS-PCR, and histopathology. We hypothesized that a real-time PCR assay would considerably improve detection of G. destructans in bats. The 100 bp sequence of the Alpha-L-Rhamnosidase gene was validated as a target for real-time PCR. The assay sensitivity was determined from serial dilution of DNA extracted from G. destructans conidia (5 × 10(-1)-5 × 10(7)), and the specificity was tested using DNA from 30 closely and distantly related fungi and 5 common bacterial pathogens. The real-time PCR assay was highly sensitive with detection limit of two G. destructans conidia per reaction at 40 PCR cycles. The assay was also highly specific as none of the other fungal or bacterial DNA cross-reacted in the real-time PCR assay. One hundred and forty-seven bat tissue samples, suspected of infection with G. destructans, were used to compare the real-time PCR assay to other methods employed for the detection of G. destructans. Real-time PCR was highly sensitive with 80 of 147 (55%) samples testing positive for G. destructans DNA. In comparison, histopathology examination revealed 64/147 (44%) positive samples. The internal transcribed spacer (ITS)-PCR yielded positive amplicon for G. destructans from 37 tissue samples (25%). The least sensitive assay was the fungal culture with only 17 tissue samples (12%) yielding G. destructans in culture. The data suggested that the real-time PCR assay is highly promising for rapid, sensitive, and specific identification of G. destructans. Further trials and inter-laboratory comparisons of this novel assay are recommended to improve the diagnosis of bat geomycosis.


Asunto(s)
Ascomicetos/aislamiento & purificación , Quirópteros/microbiología , Micología/métodos , Micosis/veterinaria , Nariz/patología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Medicina Veterinaria/métodos , Animales , Ascomicetos/genética , Glicósido Hidrolasas/genética , Micosis/diagnóstico , Micosis/microbiología , Nariz/microbiología , Sensibilidad y Especificidad
20.
Viruses ; 13(3)2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33802123

RESUMEN

In New York State, domestic animals are no longer considered rabies vector species, but given their ubiquity with humans, rabies cases in dogs and cats often result in multiple individuals requiring post-exposure prophylaxis. For over a decade, the New York State rabies laboratory has variant-typed these domestic animals to aid in epidemiological investigations, determine exposures, and generate demographic data. We produced a data set that outlined vaccination status, ownership, and rabies results. Our data demonstrate that a large percentage of felines submitted for rabies testing were not vaccinated or did not have a current rabies vaccination, while canines were largely vaccinated. Despite massive vaccination campaigns, free clinics, and education, these companion animals still occasionally contract rabies. Barring translocation events, we note that rabies-positive cats and dogs in New York State have exclusively contracted a raccoon variant. While the United States has made tremendous strides in reducing its rabies burden, we hope these data will encourage responsible pet ownership including rabies vaccinations to reduce unnecessary animal mortality, long quarantines, and post-exposure prophylaxis in humans.


Asunto(s)
Enfermedades de los Gatos/epidemiología , Enfermedades de los Perros/epidemiología , Vacunación Masiva/estadística & datos numéricos , Rabia/epidemiología , Rabia/veterinaria , Animales , Enfermedades de los Gatos/virología , Gatos , Enfermedades de los Perros/virología , Perros , Programas de Inmunización , Vacunación Masiva/veterinaria , New York/epidemiología , Mascotas/virología , Profilaxis Posexposición , Rabia/prevención & control , Vacunas Antirrábicas/uso terapéutico , Mapaches/virología
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