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Neurodegenerative diseases affect millions of people worldwide. The likelihood of developing a neurodegenerative disease rises dramatically as life expectancy increases. Although it has drawn significant attention, there is still a lack of proper effective treatments for neurodegenerative disease because the mechanisms of its development and progression are largely unknown. Extracellular vesicles (EVs) are small bi-lipid layer-enclosed nanosized particles in tissues and biological fluids. EVs are emerging as novel intercellular messengers and regulate a series of biological responses. Increasing evidence suggests that EVs are involved in the pathogenesis of neurodegenerative disorders. In this review, we summarize the recent findings of EVs in neurodegenerative diseases and bring up the limitations in the field.
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Vesículas Extracelulares , Doenças Neurodegenerativas , Humanos , Expectativa de Vida , Gotículas Lipídicas , ProbabilidadeRESUMO
Roux-en-Y gastric bypass surgery (RYGB) is one of the most effective treatments for morbid obesity. However, increased substance abuse following RYGB has been observed clinically. This study examined the effects of RYGB on the dopamine system to elucidate these observed changes in reward-related behavior. Rats were assigned to four groups: normal diet with sham surgery, ad libitum high fat (HF) diet with sham surgery, restricted HF diet with sham surgery, and HF diet with RYGB surgery. Following surgeries, rats were kept on their respective diets for 9 weeks before they were sacrificed. [3 H]SCH 23390, [3 H]Spiperone, and [3 H]WIN35 428 autoradiography was performed to quantify the effects of diet and RYGB surgery on dopamine type 1-like receptor (D1R)-like, dopamine type 2-like receptor (D2R)-like, and dopamine transporter (DAT) binding. Rats on a chronic HF diet became obese with reduced D1R-like binding within the ventrolateral striatum and the nucleus accumbens core, reduced D2R-like binding in all areas of the striatum and nucleus accumbens core and shell, and reduced DAT binding in the dorsomedial striatum. Restricted HF diet rats showed similar reductions in D1R-like and D2-R-like binding as the obese rats, and reduced DAT binding within all areas of the striatum. Both RYGB and restricted HF diet rats showed similar weight reductions, with RYGB rats showing no difference in binding compared to controls. The observed changes in binding between non-treated obese rats and RYGB rats demonstrates that HF dietary effects on the dopamine system were reversed by RYGB.
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Swine influenza virus (SIV) H3N2 with triple reassorted internal genes (TRIG) has been enzootic in Unites States since 1998. Transmission of the 2009 pandemic H1N1 (pH1N1) virus to pigs in the United States was followed by reassortment with endemic SIV, resulting in reassorted viruses that include novel H3N2 genotypes (rH3N2p). Between July and December 2011, 12 cases of human infections with swine-lineage H3N2 viruses containing the pandemic matrix (pM) gene [A(H3N2)v] were detected. Whole-genome analysis of H3N2 viruses isolated from pigs from 2009 to 2011 sequenced in this study and other available H3N2 sequences showed six different rH3N2p genotypes present in the U.S. swine population since 2009. The presence of the pM gene was a common feature among all rH3N2p genotypes, but no specific genotype appeared to predominate in the swine population. We compared the pathogenic, transmission, genetic, and antigenic properties of a human A(H3N2)v isolate and two swine H3N2 isolates, H3N2-TRIG and rH3N2p. Our in vivo study detected no increased virulence in A(H3N2)v or rH3N2p viruses compared to endemic H3N2-TRIG virus. Antibodies to cluster IV H3N2-TRIG and rH3N2p viruses had reduced cross-reactivity to A(H3N2)v compared to other cluster IV H3N2-TRIG and rH3N2p viruses. Genetic analysis of the hemagglutinin gene indicated that although rH3N2p and A(H3N2)v are related to cluster IV of H3N2-TRIG, some recent rH3N2p isolates appeared to be forming a separate cluster along with the human isolates of A(H3N2)v. Continued monitoring of these H3N2 viruses is necessary to evaluate the evolution and potential loss of population immunity in swine and humans.
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Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/patogenicidade , Influenza Humana/virologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/transmissão , Sequência de Aminoácidos , Animais , Humanos , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/genética , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Filogenia , Vírus Reordenados/classificação , Vírus Reordenados/genética , Vírus Reordenados/isolamento & purificação , Vírus Reordenados/patogenicidade , Alinhamento de Sequência , Suínos , Doenças dos Suínos/virologiaRESUMO
BACKGROUND: After identifying a student with triple-reassortant swine influenza virus (SIV) infection and pig exposure at a livestock event, we investigated whether others were infected and if human-to-human transmission occurred. METHODS: We conducted a cohort study and serosurvey among persons exposed to (1) event pigs, (2) other pigs, (3) the index case, and (4) persons without pig or index case exposure. Confirmed cases had respiratory specimens positive for SIV within 2 weeks of the index case's illness. Probable and suspected cases had illness and (1) exposure to any pig or (2) contact with a confirmed case preceding illness. Probable cases were seropositive. Suspected cases did not give serum samples. RESULTS: Of 99 event pig-exposed students, 72 (73%) participated in the investigation, and 42 (42%) provided serum samples, of whom 17 (40%) were seropositive and 5 (12%) met case criteria. Of 9 students exposed to other pigs, 2 (22%) were seropositive. Of 8 index case-exposed persons and 10 without exposures, none were seropositive. Pig-exposed persons were more likely to be seropositive than persons without pig exposure (37% vs 0%, P < .01). CONCLUSIONS: We identified an outbreak of human SIV infection likely associated with a livestock event; there was no evidence of human-to-human transmission.
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Surtos de Doenças , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/virologia , Vírus Reordenados/isolamento & purificação , Doenças dos Suínos/virologia , Animais , Anticorpos Antivirais/sangue , Sequência de Bases , Estudos de Coortes , Feminino , Humanos , Influenza Humana/epidemiologia , Influenza Humana/transmissão , Masculino , Dados de Sequência Molecular , Estudos Retrospectivos , Estudos Soroepidemiológicos , South Dakota/epidemiologia , Estudantes , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/transmissão , Adulto JovemRESUMO
Clinical and preclinical studies have shown dysfunctions in genetic expression and neurotransmission of γ-Aminobutyric acid (GABA), GABAA receptor subunits, and GABA-synthesizing enzymes GAD67 and GAD65 in schizophrenia. It is well documented that there is significant weight gain after chronic neuroleptic treatment in humans. While there are limited studies on the effects of diet on GABA signaling directly, a change in diet has been used clinically as an adjunct to treatment for schizophrenic relief. In this study, rats chronically consumed either a chow diet (CD) or a 60% high-fat diet (HFD) and drank from bottles that contained one of the following solutions: water, haloperidol (1.5 mg/kg), or olanzapine (10 mg/kg) for four weeks. Rats were then euthanized and their brains were processed for GABAA in-vitro receptor autoradiography using [3H] flunitrazepam. A chronic HFD treatment yielded significantly increased [3H] flunitrazepam binding in the rat cerebellum independent of neuroleptic treatment. The desynchronization between the prefrontal cortex and the cerebellum is associated with major cognitive and motor dysfunctions commonly found in schizophrenic symptomatology, such as slowed reaction time, motor dyscoordination, and prefrontal activations related to speech fluency and cognitive alertness. These data support the notion that there is a dietary effect on GABA signaling within the cerebellum, as well as the importance of considering nutritional intervention methods as an adjunct treatment for patients chronically treated with neuroleptics. Finally, we indicate that future studies involving the analysis of individual patient's genetic profiles will further assist towards a precision medicine approach to the treatment of schizophrenia.
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Antipsicóticos/administração & dosagem , Cerebelo/efeitos dos fármacos , Dieta Hiperlipídica , Flunitrazepam/metabolismo , Haloperidol/administração & dosagem , Esquizofrenia/tratamento farmacológico , Animais , Antipsicóticos/farmacologia , Autorradiografia , Encéfalo/metabolismo , Haloperidol/farmacologia , Masculino , Olanzapina/administração & dosagem , Olanzapina/farmacologia , Córtex Pré-Frontal/metabolismo , Ensaio Radioligante , Ratos , Ácido gama-Aminobutírico/metabolismoRESUMO
Prior to the introduction of the 2009 pandemic H1N1 virus from humans into pigs, four phylogenetic clusters (α-, ß-, γ- and δ) of the haemagglutinin (HA) gene from H1 influenza viruses could be found in US swine. Information regarding the antigenic relatedness of the H1 viruses was lacking due to the dynamic and variable nature of swine lineage H1. We characterized 12 H1 isolates from 2008 by using 454 genome-sequencing technology and phylogenetic analysis of all eight gene segments and by serological cross-reactivity in the haemagglutination inhibition (HI) assay. Genetic diversity was demonstrated in all gene segments, but most notably in the HA gene. The gene segments from the 2009 pandemic H1N1 formed clusters separate from North American swine lineage viruses, suggesting progenitors of the pandemic virus were not present in US pigs immediately prior to 2009. Serological cross-reactivity paired with antigenic cartography demonstrated that the viruses in the different phylogenetic clusters are also antigenically divergent.
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Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H1N2/classificação , Vírus da Influenza A Subtipo H1N2/isolamento & purificação , Suínos/virologia , Animais , Análise por Conglomerados , Variação Genética , Genótipo , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N2/genética , Vírus da Influenza A Subtipo H1N2/imunologia , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Sorotipagem , Estados UnidosRESUMO
Influenza A pandemic (H1N1) 2009 virus continues to rapidly spread worldwide. In 2009, pandemic (H1N1) 2009 infection in a domestic cat from Iowa was diagnosed by a novel PCR assay that distinguishes between Eurasian and North American pandemic (H1N1) 2009 virus matrix genes. Human-to-cat transmission is presumed.
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Animais Domésticos/virologia , Doenças do Gato/virologia , Surtos de Doenças , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Animais , Líquido da Lavagem Broncoalveolar/virologia , Doenças do Gato/diagnóstico por imagem , Gatos , Linhagem Celular , Humanos , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/transmissão , Influenza Humana/virologia , Masculino , Infecções por Orthomyxoviridae/diagnóstico por imagem , Infecções por Orthomyxoviridae/virologia , Reação em Cadeia da Polimerase/métodos , RNA Viral/análise , RNA Viral/isolamento & purificação , RadiografiaRESUMO
Respiratory swab samples were collected from 5 pet ferrets (Mustela putorius furo) exhibiting influenza-like illness. The ferrets represented 3 households in 2 states. In each case, the owners reported influenza-like illness in themselves or family members prior to the onset of a similar illness in the ferrets. Real-time reverse transcription polymerase chain reaction assays designed for the detection of the 2009 H1N1 Influenza A virus were conducted in the state animal health laboratories. The assays included detection of the matrix gene of Influenza A virus and neuraminidase gene specific for 2009 H1N1 virus. Samples were positive for both screening assays. The samples were confirmed positive by the National Veterinary Services Laboratories. The history of illness in family members prior to illness in the ferrets suggests that Influenza A virus was transmitted from humans to the ferrets.
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Influenza Humana/transmissão , Infecções por Orthomyxoviridae/diagnóstico , Animais , Animais Domésticos/virologia , Transmissão de Doença Infecciosa/veterinária , Furões , Hemaglutininas Virais/genética , Humanos , Vírus da Influenza A Subtipo H1N1/enzimologia , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Neuraminidase/genética , Oregon , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/transmissão , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Exercise is known to have a myriad of health benefits. There is much to be learned from the effects of exercise and its potential for prevention, attenuation and treatment of multiple neuropsychiatric diseases and behavioral disorders. Furthermore, recent data and research on exercise benefits with respect to major health crises, such as, that of opioid and general substance use disorders, make it very important to better understand and review the mechanisms of exercise and how it could be utilized for effective treatments or adjunct treatments for these diseases. In addition, mechanisms, epigenetics and sex differences are examined and discussed in terms of future research implications.
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Exercício Físico , Transtornos Relacionados ao Uso de Substâncias , Feminino , Humanos , MasculinoRESUMO
In August 2007, pigs and people became clinically affected by an influenza-like illness during attendance at an Ohio county fair. Influenza A virus was identified from pigs and people, and the virus isolates were characterized as swine H1N1 similar to swine viruses currently circulating in the U.S. pig population. The swine isolate, A/SW/OH/511445/2007 (OH07), was evaluated in an experimental challenge and transmission study reported here. Our results indicate that the OH07 virus was pathogenic in pigs, was transmissible among pigs, and failed to cross-react with many swine H1 anti-sera. Naturally exposed pigs shed virus as early as 3 days and as long as 7 days after contact with experimentally infected pigs. This suggests there was opportunity for exposure of people handling the pigs at the fair. The molecular analysis of the OH07 isolates demonstrated that the eight gene segments were similar to those of currently circulating triple reassortant swine influenza viruses. However, numerous nucleotide changes leading to amino acid changes were demonstrated in the HA gene and throughout the genome as compared to contemporary swine viruses in the same genetic cluster. It remains unknown if any of the amino acid changes were related to the ability of this virus to infect people. The characteristics of the OH07 virus in our pig experimental model as well as the documented human transmission warrant close monitoring of the spread of this virus in pig and human populations.
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Vírus da Influenza A/classificação , Influenza Humana/virologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Animais , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Influenza Humana/epidemiologia , Ohio/epidemiologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Filogenia , Suínos , Doenças dos Suínos/epidemiologiaRESUMO
INTRODUCTION: Exercise programs have been shown to be effective for both reducing risk for, and intervention following, substance abuse behaviors in both clinical and preclinical studies. Less is known, however, regarding the underlying neurobiological substrates involved in these changes in drug seeking behavior. In this study, we assessed cannabinoid receptor (CB1) levels throughout the brain which are key in endocannabinoid signaling following chronic aerobic exercise. METHODS: Male and female Lewis young adult rats were grouped into exercise and sedentary groups at 8â¯weeks of age. Exercise rats ran on a treadmill at 10â¯m/min, 5â¯days/week, for 6â¯weeks, whereas sedentary rats remained in their home cage. Rats were euthanized after 6â¯weeks, and in vitro receptor autoradiography was performed using [3H] SR141716A to quantify CB1 receptors throughout the brain. RESULTS: Exercise rats did not show significantly different [3H] SR141716A binding levels as compared to sedentary rats; however, an overall sex effect was found, where males had 29% higher [3H] SR141716A binding within the pyramidal layer of the hippocampus when compared to females. The chronic aerobic exercise regimen did not produce any changes in CB1 receptor levels. CONCLUSIONS: The present study found that chronic exercise during young adulthood did not alter cannabinoid CB1 receptor levels in the brain. Therefore, previously reported decreased cocaine preference in parallel treated cohorts did not involve exercise induced changes in CB1 levels which is key for endocannabinoid signaling.
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Condicionamento Físico Animal/fisiologia , Receptor CB1 de Canabinoide/efeitos dos fármacos , Receptor CB1 de Canabinoide/fisiologia , Animais , Autorradiografia , Encéfalo/metabolismo , Endocanabinoides/metabolismo , Endocanabinoides/fisiologia , Feminino , Hipocampo/metabolismo , Masculino , Ratos , Ratos Endogâmicos Lew , Fatores SexuaisRESUMO
INTRODUCTION: Exercise has been shown to be effective for preventing and treating substance abuse in both clinical and preclinical studies. Less is known, however, regarding the underlying neurobiological mechanisms driving these changes in drug-seeking behavior. One possibility is that exercise may alter the mesolimbic dopamine pathway in such a way that makes drugs of abuse less salient and/or rewarding. METHODS: To examine possible exercise-induced changes in dopamine signaling, male and female Lewis rats were split into exercise and sedentary groups at 8 wk of age. Exercise rats were run on a treadmill at 10 m·min, 5 d·wk, for 6 wk, whereas sedentary rats remained in their home cage. Rats were killed after the 6 wk of treatment, and their brains were used for in vitro autoradiography using [H]SCH 23,390, [H]Spiperone, and [H]WIN55,428 ligands to quantify dopamine type 1-like receptor (D1R)-like, dopamine type 2-like receptor (D2R)-like, and dopamine transporter binding, respectively. RESULTS: Exercised rats had 18% and 21% lower D1R-like binding levels compared to sedentary rats within the olfactory tubercle and nucleus accumbens shell, respectively. In addition, male and female exercise rats showed greater D2R-like binding levels within the dorsomedial caudate putamen (30%), ventrolateral caudate putamen (24%), and ventromedial caudate putamen (27%), as well as the olfactory tubercle (19%). Greater D2R-like binding in the nucleus accumbens core (24%) and shell (25%) of exercised rats compared with sedentary rats approached significance. No effects were found for dopamine transporter binding. CONCLUSIONS: These findings support the hypothesis that aerobic exercise results in changes in the mesolimbic pathway that could mediate exercise-induced attenuation of drug-seeking behavior.
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Encéfalo/metabolismo , Transtornos Relacionados ao Uso de Cocaína/metabolismo , Transtornos Relacionados ao Uso de Cocaína/terapia , Terapia por Exercício , Condicionamento Físico Animal , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Autorradiografia , Transtornos Relacionados ao Uso de Cocaína/prevenção & controle , Feminino , Masculino , Núcleo Accumbens/metabolismo , Tubérculo Olfatório/metabolismo , Putamen/metabolismo , Ratos Endogâmicos LewRESUMO
Despite successful eradication of pseudorabies virus (PRV) from the commercial pig industry in the United States in 2004, large populations of feral swine in certain regions act as wildlife reservoirs for the virus. Given the threat of reintroduction of the virus into domestic herds, a rapid, reliable, easily implemented assay is needed for detection of PRV. Although a real-time PCR (rtPCR) assay exists, improvements in rtPCR technology and a greater understanding of the diversity of PRV strains worldwide require an assay that would be easier to implement, more cost effective, and more specific. We developed a single-tube, rapid rtPCR that is capable of detecting 10 copies of PRV glycoprotein B ( gB) DNA per 20-µL total volume reaction. The assay did not produce a false-positive in samples known to be negative for the virus. The assay was negative for genetically similar herpesviruses and other porcine viruses. Our assay is a highly specific and sensitive assay that is also highly repeatable and reproducible. The assay should be a useful tool for early detection of PRV in pigs in the case of a suspected introduction or outbreak situation.
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DNA Viral/análise , Herpesvirus Suídeo 1/isolamento & purificação , Pseudorraiva/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Doenças dos Suínos/diagnóstico , Proteínas do Envelope Viral/análise , Animais , Pseudorraiva/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Sus scrofa , Suínos , Doenças dos Suínos/virologiaRESUMO
Equine-origin H3N8 has circulated in dogs in the United States since 1999. A genetically and antigenically distinct avian-origin H3N2 canine influenza was detected in March of 2015 in Chicago, Illinois. Subsequent outbreaks were reported with over 1000 dogs in the Midwest affected followed by 23 additional states with detections within 5 months. The potential for canine-to-swine transmission was unknown. Experimental infection in pigs showed this virus does not replicate efficiently in swine.
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Doenças do Cão/virologia , Vírus da Influenza A Subtipo H3N2/fisiologia , Influenza Aviária/virologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Replicação Viral , Animais , Aves , Chicago/epidemiologia , Surtos de Doenças , Cães/virologia , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Vírus da Influenza A Subtipo H3N8/genética , Vírus da Influenza A Subtipo H3N8/isolamento & purificação , Influenza Aviária/epidemiologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Filogenia , Suínos , Estados Unidos/epidemiologiaRESUMO
The H1 subtype of influenza A viruses (IAVs) has been circulating in swine since the 1918 human influenza pandemic. Over time, and aided by further introductions from nonswine hosts, swine H1 viruses have diversified into three genetic lineages. Due to limited global data, these H1 lineages were named based on colloquial context, leading to a proliferation of inconsistent regional naming conventions. In this study, we propose rigorous phylogenetic criteria to establish a globally consistent nomenclature of swine H1 virus hemagglutinin (HA) evolution. These criteria applied to a data set of 7,070 H1 HA sequences led to 28 distinct clades as the basis for the nomenclature. We developed and implemented a web-accessible annotation tool that can assign these biologically informative categories to new sequence data. The annotation tool assigned the combined data set of 7,070 H1 sequences to the correct clade more than 99% of the time. Our analyses indicated that 87% of the swine H1 viruses from 2010 to the present had HAs that belonged to 7 contemporary cocirculating clades. Our nomenclature and web-accessible classification tool provide an accurate method for researchers, diagnosticians, and health officials to assign clade designations to HA sequences. The tool can be updated readily to track evolving nomenclature as new clades emerge, ensuring continued relevance. A common global nomenclature facilitates comparisons of IAVs infecting humans and pigs, within and between regions, and can provide insight into the diversity of swine H1 influenza virus and its impact on vaccine strain selection, diagnostic reagents, and test performance, thereby simplifying communication of such data. IMPORTANCE A fundamental goal in the biological sciences is the definition of groups of organisms based on evolutionary history and the naming of those groups. For influenza A viruses (IAVs) in swine, understanding the hemagglutinin (HA) genetic lineage of a circulating strain aids in vaccine antigen selection and allows for inferences about vaccine efficacy. Previous reporting of H1 virus HA in swine relied on colloquial names, frequently with incriminating and stigmatizing geographic toponyms, making comparisons between studies challenging. To overcome this, we developed an adaptable nomenclature using measurable criteria for historical and contemporary evolutionary patterns of H1 global swine IAVs. We also developed a web-accessible tool that classifies viruses according to this nomenclature. This classification system will aid agricultural production and pandemic preparedness through the identification of important changes in swine IAVs and provides terminology enabling discussion of swine IAVs in a common context among animal and human health initiatives.
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The probability of detecting influenza A virus (IAV) in oral fluid (OF) specimens was calculated for each of 13 assays based on real-time reverse-transcription polymerase chain reaction (rRT-PCR) and 7 assays based on virus isolation (VI). The OF specimens were inoculated with H1N1 or H3N2 IAV and serially diluted 10-fold (10(-1) to 10(-8)). Eight participating laboratories received 180 randomized OF samples (10 replicates × 8 dilutions × 2 IAV subtypes plus 20 IAV-negative samples) and performed the rRT-PCR and VI procedure(s) of their choice. Analysis of the results with a mixed-effect logistic-regression model identified dilution and assay as variables significant (P < 0.0001) for IAV detection in OF by rRT-PCR or VI. Virus subtype was not significant for IAV detection by either rRT-PCR (P = 0.457) or VI (P = 0.101). For rRT-PCR the cycle threshold (Ct) values increased consistently with dilution but varied widely. Therefore, it was not possible to predict VI success on the basis of Ct values. The success of VI was inversely related to the dilution of the sample; the assay was generally unsuccessful at lower virus concentrations. Successful swine health monitoring and disease surveillance require assays with consistent performance, but significant differences in reproducibility were observed among the assays evaluated.
La probabilité de détecter le virus de l'influenza A (VIA) dans des échantillons de fluide oral (FO) a été calculée pour chacune des 13 épreuves basées sur une réaction d'amplification en chaine en temps réel utilisant la polymérase réverse (rRT-PCR) et 7 épreuves basées sur l'isolement viral (IV). Les échantillons de FO ont été inoculés avec du VIA H1N1 ou H3N2 et dilués en série par facteur de 10 (10−1 à 10−8). Huit laboratoires participants ont reçu 180 échantillons randomisés de FO (10 réplicats × 8 dilutions × 2 sous-types de VIA plus 20 échantillons témoins négatifs sans VIA) et ont réalisé la méthode de rRT-PCR et d'IV de leur choix. L'analyse des résultats à l'aide d'un modèle de régression logistique pour les effets mélangés a identifié la dilution et l'épreuve comme étant des variables significatives (P < 0,0001) pour la détection de VIA dans du FO par rRT-PCR ou IV. Le sous-type de virus n'était pas significatif pour la détection de VIA soit par rRT-PCR (P = 0,457) ou par IV (P = 0,101). Pour les épreuves rRT-PCR les valeurs seuils de cycle (Ct) augmentaient de manière constante avec la dilution mais variaient énormément. Ainsi, il n'était pas possible de prédire le succès de l'IV sur la base des valeurs de Ct. Le succès de l'IV était inversement relié à la dilution de l'échantillon; l'épreuve était généralement négative aux faibles concentrations de virus. Pour avoir du succès dans la surveillance des maladies et de la santé des porcs il est nécessaire d'avoir des épreuves avec des performances constantes, mais des différences significatives dans la reproductibilité ont été observées parmi les épreuves évaluées.(Traduit par Docteur Serge Messier).
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Vírus da Influenza A Subtipo H1N1 , Vírus da Influenza A Subtipo H3N2 , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Saliva/virologia , Doenças dos Suínos/virologia , Animais , Feminino , Infecções por Orthomyxoviridae/diagnóstico , Infecções por Orthomyxoviridae/veterinária , Infecções por Orthomyxoviridae/virologia , Suínos , Doenças dos Suínos/diagnósticoRESUMO
Hemagglutination inhibition (HI) has been a reliable method for determining porcine antibody levels to the well-characterized swine influenza virus (SIV) H1N1 and H3N2 subtypes. However, the recent emergence of the novel H1N2 serotype of SIV and the persistence of 2 other serotypes (H1N1 and H3N2) in the United States swine population represents a significant challenge to diagnostics. Both standardized and modified HI protocols were used in a blinded study to examine a collection of 50 control sera representing a total of 12 swine that were experimentally inoculated with one of the 3 SIV subtypes. Using these control sera data, a statistical basis for analysis was established in an attempt to classify 30 field sera with known case histories or seroprevalance into SIV serotype categories. By this approach 57% of the field sera could be classified into specific categories. The remaining samples that could not be classified reliably were most likely composed of heterogeneous anti-SIV antibody populations. These results indicate that although serological differentiation might be possible in a controlled environment, applications of these methods to field samples are currently problematic. Approaches other than HI will be required to fulfill the current need for SIV diagnostics and surveillance when specific serotype identification is required.
Assuntos
Anticorpos Antivirais/análise , Vírus da Influenza A/imunologia , Infecções por Orthomyxoviridae/veterinária , Animais , Testes de Inibição da Hemaglutinação/veterinária , Infecções por Orthomyxoviridae/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Sorotipagem/veterinária , SuínosRESUMO
Porcine reproductive and respiratory syndrome virus (PRRSV) causes significant reproductive losses in the sow herd and respiratory disease in growing pigs. The virus belongs to the family Arteriviridae and there are two major genotypes. Type 1 is represented by Lelystad virus, the European prototype virus, and Type 2 is represented by the North American prototype virus, VR-2332. Depending on husbandry, immune status of the herd, and virulence of the isolate, the severity of disease and magnitude of economic loss can be variable. Vaccine use is not always successful indicating a lack of cross-protection between vaccine strains and circulating wild-type viruses. To date, there is no clear method to demonstrate if a vaccine confers protection against a specific isolate except for empirical animal studies. In 2006, a new lineage of Type 2 PRRSV emerged in Chinese swine herds that were suffering dramatic losses resulting in those viruses being described as "Highly Pathogenic PRRSV" (HP-PRRSV). Experimental reproduction of severe disease with HP-PRRSV isolates and virus derived from HP-PRRSV clones demonstrated the causal role of this virus. Recently, partial heterologous protection has been reported for Type 1 and Type 2 attenuated PRRSV vaccines against challenge by different Chinese HP-PRRSV isolates providing some hope for reducing economic loss. This paper reports the efficacy of a commercially available Type 2 attenuated vaccine in young pigs against heterologous challenge with a Chinese and Vietnamese HP-PRRSV isolate. When compared to unvaccinated pigs, vaccination decreased the length of viremia and viral titer, diminished the time of high fever and reduced macroscopic lung scores following homologous and heterologous PRRSV challenge. These results demonstrate the potential use of vaccine as an aid in the control of HP-PRRSV outbreaks.
Assuntos
Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vacinas Virais/imunologia , Animais , Líquido da Lavagem Broncoalveolar/virologia , Imunidade Humoral , Pulmão/patologia , Pulmão/virologia , Suínos , Vacinação/veterinária , Vacinas Atenuadas/imunologia , Carga ViralRESUMO
BACKGROUND: Swine influenza A virus (IAV) reassortment with 2009 H1N1 pandemic (H1N1pdm09) virus has been documented, and new genotypes and subclusters of H3N2 have since expanded in the US swine population. An H3N2 variant (H3N2v) virus with the H1N1pdm09 matrix gene and the remaining genes of swine triple reassortant H3N2 caused outbreaks at agricultural fairs in 2011-2012. METHODS: To assess commercial swine IAV vaccines' efficacy against H3N2 viruses, including those similar to H3N2v, antisera to three vaccines were tested by hemagglutinin inhibition (HI) assay against contemporary H3N2. Vaccine 1, with high HI cross-reactivity, was further investigated for efficacy against H3N2 virus infection in pigs with or without maternally derived antibodies (MDA). In addition, efficacy of a vaccine derived from whole inactivated virus (WIV) was compared with live attenuated influenza virus (LAIV) against H3N2. RESULTS: Hemagglutinin inhibition cross-reactivity demonstrated that contemporary swine H3N2 viruses have drifted from viruses in current swine IAV vaccines. The vaccine with the highest level of HI cross-reactivity significantly protected pigs without MDA. However, the presence of MDA at vaccination blocked vaccine efficacy. The performance of WIV and LAIV was comparable in the absence of MDA. CONCLUSIONS: Swine IAV in the United States is complex and dynamic. Vaccination to minimize virus shedding can help limit transmission of virus among pigs and people. However, vaccines must be updated. A critical review of the use of WIV in sows is required in the context of the current IAV ecology and vaccine application in pigs with MDA.
Assuntos
Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/imunologia , Animais , Anticorpos Antivirais/imunologia , Reações Cruzadas , Vírus da Influenza A Subtipo H3N2/genética , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Suínos , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Estados UnidosRESUMO
BACKGROUND: Understanding the ecology and evolution of influenza A viruses (IAV) in mammalian hosts is critical to reduce disease burden in production animals and lower zoonotic infection risk in humans. Recent advances in influenza surveillance in US swine populations allow for timely epidemiological, phylogenetic, and virological analyses that monitor emergence of novel viruses and assess changes in viral population dynamics. METHODS: To better understand IAV in the North American swine population, we undertook a phylogenetic analysis of 1075 HA, 1049 NA, and 1040 M sequences of IAV isolated from US swine during 2009-2012 through voluntary and anonymous submissions to the US Department of Agriculture IAV swine surveillance system. RESULTS: Analyses revealed changes in population dynamics among multiple clades of A/H1N1, A/H3N2, and A/H1N2 cocirculating in US swine populations during 2009-2012. Viral isolates were categorized into one of seven genetically and antigenically distinct hemagglutinin lineages: H1α, H1ß, H1γ, H1δ1, H1δ2, H1pdm09, and H3 cluster IV. There was an increase in occurrence of H1δ1 in samples submitted, with a concurrent decrease in H1pdm09. H3 cluster IV exhibited increasing diversification, warranting a re-evaluation of phylogenetic nomenclature criteria. Although H3N2 represented 25% of identified viruses, this subtype was reported in increasing proportion of sequenced isolates since late 2011. CONCLUSIONS: Surveillance and reporting of IAV in US swine have increased since 2009, and we demonstrate a period of expanded viral diversity. These data may be used to inform intervention strategies of vaccine and diagnostic updates and changes in swine health management.