Equine infectious anemia virus (EIAV) causes rapid development of acute disease followed by recurring episodes of fever, thrombocytopenia and viremia, termed chronic EIA. Most infected horses control the virus by immune mechanisms and become inapparent carriers. To further our understanding of the equine immune response to EIAV, a multi-probe ribonuclease protection assay (RPA) was developed to quantitate equine-specific cytokine mRNAs. Eleven template plasmids specific to ten equine cytokine genes and the ?-actin gene were generated, from which radiolabeled anti-sense RNA probes were produced. The RPA simultaneously quantitated mRNA levels of interleukin (IL)-1, IL-1, IL-6, IL-8, IL-10, IL-12 p35, IL-12 p40, interferon (IFN)-, transforming growth factor (TGF)-1 and tumor necrosis factor (TNF)- in equine peripheral blood mononuclear cells and equine monocyte-derived macrophages (EMDM). The assay detected as few as 5105 RNA molecules and displayed coefficients of variation of 0.03-0.08 when normalized to -actin expression. Using this RPA, cytokine expression in EMDM infected with 2 molecularly cloned viruses (EIAV17 and EIAV19) was determined. EIAV17 varies from EIAV19 only in env, rev and LTR and causes fatal disease in Shetland ponies. When added to EMDM cultures, virulent EIAV17 stimulated expression of IL-1, IL-1, IL-6, IL-10 and TNF-. These cytokine mRNAs were significantly elevated by 0.5 to 1 hr post infection (hpi) and returned to basal levels by 12 to 24 hpi, indicating modulation by early event(s), such as receptor binding. In contrast to EIAV17, EIAV19 is avirulent in vivo and failed to induce any of the tested cytokines in EMDM. These data show a direct correlation between the virulence of the EIAV clone and the induction of cytokines. The cytokines stimulated by EIAV17 may contribute to EIA-associated symptoms, enhance viral replication in the host, and regulate the host immune response. To determine whether cytokine induction requires EIAV17 replication, EMDM cultures were exposed to UV-inactivated EIAV17 and cytokine induction was monitored. UV-inactivation did not block cytokine induction by EIAV17, suggesting dispensability of viral replication. Given that EIAV17 induces cytokines in a rapid and replication-independent manner, the activation of cytokine expression is likely mediated by binding of EIAV17 to equine macrophage receptor(s).

Equine infectious anemia virus (EIAV) causes rapid development of acute disease followed by recurring episodes of fever, thrombocytopenia and viremia, termed chronic EIA. Most infected horses control the virus by immune mechanisms and become inapparent carriers. To further our understanding of the equine immune response to EIAV, a multi-probe ribonuclease protection assay (RPA) was developed to quantitate equine-specific cytokine mRNAs. Eleven template plasmids specific to ten equine cytokine genes and the ?-actin gene were generated, from which radiolabeled anti-sense RNA probes were produced. The RPA simultaneously quantitated mRNA levels of interleukin (IL)-1, IL-1, IL-6, IL-8, IL-10, IL-12 p35, IL-12 p40, interferon (IFN)-, transforming growth factor (TGF)-1 and tumor necrosis factor (TNF)- in equine peripheral blood mononuclear cells and equine monocyte-derived macrophages (EMDM). The assay detected as few as 5105 RNA molecules and displayed coefficients of variation of 0.03-0.08 when normalized to -actin expression. Using this RPA, cytokine expression in EMDM infected with 2 molecularly cloned viruses (EIAV17 and EIAV19) was determined. EIAV17 varies from EIAV19 only in env, rev and LTR and causes fatal disease in Shetland ponies. When added to EMDM cultures, virulent EIAV17 stimulated expression of IL-1, IL-1, IL-6, IL-10 and TNF-. These cytokine mRNAs were significantly elevated by 0.5 to 1 hr post infection (hpi) and returned to basal levels by 12 to 24 hpi, indicating modulation by early event(s), such as receptor binding. In contrast to EIAV17, EIAV19 is avirulent in vivo and failed to induce any of the tested cytokines in EMDM. These data show a direct correlation between the virulence of the EIAV clone and the induction of cytokines. The cytokines stimulated by EIAV17 may contribute to EIA-associated symptoms, enhance viral replication in the host, and regulate the host immune response. To determine whether cytokine induction requires EIAV17 replication, EMDM cultures were exposed to UV-inactivated EIAV17 and cytokine induction was monitored. UV-inactivation did not block cytokine induction by EIAV17, suggesting dispensability of viral replication. Given that EIAV17 induces cytokines in a rapid and replication-independent manner, the activation of cytokine expression is likely mediated by binding of EIAV17 to equine macrophage receptor(s).

Orientador: João Pessoa Araujo Junior / Resumo: O Vírus da Anemia Infecciosa Equina (VAIE) é um lentivírus que infecta equídeos causando a Anemia Infecciosa Equina. A doença possui distribuição mundial e o principal método de controle empregado é a eutanásia dos animais positivos, uma vez que não existe cura ou vacina disponível. No Brasil, a região do Pantanal é endêmica para a doença e, somente nessas áreas, a eutanásia não é obrigatória. A alta variação genética de lentivírus durante uma infecção prolongada é bem conhecida em várias espécies e também descrita em sequências de VAIE de outros países. Não há sequência genômica brasileira completa descrita ou mesmo um estudo da variação genética do vírus em um ambiente endêmico como o Pantanal Brasileiro. Com isso, este trabalho teve como objetivos a caracterização molecular do VAIE em equinos da região do Pantanal Brasileiro, e a padronização da PCR quantitativa (qPCR) para detecção do DNA proviral de VAIE. Duas amostras de plasma equino positivas para VAIE foram submetidas ao sequenciamento do genoma completo utilizando uma combinação de técnicas tradicionais e de nova geração. O genoma a partir do RNA viral foi obtido, anotado e comparado com sequências virais obtidas de animais naturalmente infectados em outros países. As sequências provenientes do Pantanal apresentaram identidade entre 75 e 77 % com sequências de outros países e 88,54 % entre si, classificando-as em um clado individual na árvore filogenética dos vírus já descritos, exibindo a maior variação genética de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Equine infectious anemia virus (EIAV) is a lentivirus that infects equids and causes equine infectious anemia (EIA). This disease presents worldwide distribution and the main control method is the euthanasia of positive animals, since there is no cure or vaccine available. The Pantanal region in Brazil is endemic for the disease, and euthanasia is not mandatory in this area. The high lentivirus genetic variation during a prolonged infection is well known in several species and also described in EIAV sequences in other countries. There are no Brazilian viral genomic sequences available or even a study of genetic variation in an environment such as Brazilian Pantanal. This work aimed to characterize the EIAV complete genome in equines from Brazilian Pantanal and to standardize a quantitative real time PCR (qPCR) for detection of EIAV proviral DNA. Two plasma samples of EIAV positive horses were submitted to massive sequencing by combination of Sanger and NGS sequencing. The complete genome from viral RNA was obtained, annotated and compared with viral sequences of naturally infected animals from other countries. Sequences from Pantanal showed identity between 75% and 77% with other countries sequences and 88.54% with each other, classifying them into an individual cluster in EIAV cladogram and exhibiting the greatest genetic variation between sequences from the same country. With viral envelope gene analysis, both Brazilian sequences were classified as two quasispecies. A qPCR ... (Complete abstract click electronic access below) / Doutor

Submitted by (edna.saturno@ufrpe.br) on 2016-10-14T17:39:52Z No. of bitstreams: 1 Luciana Cavalcanti Arruda Coutinho.pdf: 1249795 bytes, checksum: d8c5b0923169bdb4b101bcf96c920d9f (MD5) / Made available in DSpace on 2016-10-14T17:39:52Z (GMT). No. of bitstreams: 1 Luciana Cavalcanti Arruda Coutinho.pdf: 1249795 bytes, checksum: d8c5b0923169bdb4b101bcf96c920d9f (MD5) Previous issue date: 2011-02-22 / Equine Infectious Anemia (EIA) is an important lentivirose in horses, characterized by a chronic and degenerative profile, causing many economic losses. It is considered that animals exposed to the virus and underwent serological evidence, when considered positive, remain so throughout life, which justifies the great concern and disease surveillance. The aim of this study was to use Pichia pastoris yeast cells for protein production of p26 gag region of Equine Infectious Anemia Virus (EIAV) for diagnostic purposes. The p26 gene of EIAV was optimized through the codon usage strategy to be expressed in cells of the Pichia pastoris yeast. The insert was cloned into pPICZαA expression vector after appropriate enzymatic digestion. P. pastoris transformed with the construction pPICZαAp26 were induced to express the p26 recombinant protein under the regulation of AOX1 promoter by adding methanol to the culture medium. The p26 recombinant protein was identified by RT-PCR and Dot blotting assay using anti-His antibody. Further studies are needed to optimize bioprocesses involved in this system in order to obtain a stable, purified and useful antigen for diagnostic purposes. / A Anemia Infecciosa Equina (AIE) é uma importante lentivirose em equídeos, caracterizada por causar um quadro crônico e degenerativo, trazendo muitos prejuízos econômicos. Considera-se que animais expostos aos vírus e submetidos à prova sorológica, quando considerados positivos, assim permanecerão por toda vida, fato que justifica a grande preocupação e vigilância da doença. Neste trabalho objetivou-se utilizar células da levedura Pichia pastoris para produção da proteína p26 da região gag do vírus da anemia infecciosa equina (VAIE) para fins de diagnóstico. O gene da proteína p26 do VAIE foi sintetizado e otimizado por meio da utilização de códons preferenciais para ser expresso em célula da levedura Pichia pastoris. O inserto foi subclonado em vetor de expressão pPICZαA após digestão enzimática apropriada. Células de P. pastoris transformadas com a construção pPICZαAp26 foram induzidas a expressarem a proteína recombinante p26 sob regulação do promotor AOX1 através da adição de metanol ao meio de cultura. A análise quanto à produção da proteína recombinante e sua identificação foram realizadas através de RT-PCR e Dot blotting utilizando anticorpo anti-His.

Equine infectious anemia virus (EIAV) has been used as a model to investigate protective mechanisms against lentiviruses. Unlike other lentiviruses, EIAV replication can be eventually controlled in most infected horses leading to an inapparent carrier state free of overt clinical signs which can last for many years. Maintenance of this carrier state is absolutely dependent on active immune responses as evidenced by the fact that immunosuppressive drugs can induce the recurrence of disease. However, the immune mechanisms that are responsible for this control of infection are not yet identified. As the resolution of the initial infection is correlated with the appearance of the virus-specific cytotoxic T lymphocytes (CTL), it appears that cellular immune responses play an important role. However, most studies into this protective mechanism have been limited to the identification of specific epitopes, usually at a single time point in the infection. Few studies have examined the cellular immune responses to the viral antigens throughout the infection period. Since the virus undergoes rapid mutation following infection, the adaptive immune response must also evolve to meet this challenge. Previously, the EIAV envelope (gp90) protein was shown to be the primary determinant of vaccine efficacy. Here, we hypothesized that the maturation of cellular immune responses is a lengthy process and involves envelope-specific T cell recognition shifting from immunodominant variable determinants to conserved immunorecessive determinants during the initial stages of the EIAV infection. The first part of this dissertation was to develop a new in vivo method to identify envelope-specific T cell responses. The second part of this dissertation was to investigate whether envelope-specific T cell recognition evolved in EIAV-infected ponies. Finally, the mechanisms for this T cell immunodominant shifting were also investigated from the point of both virus sequence mutation and T cell clone expansion and contraction. Also, a new EIAV attenuated vaccine which contained a consensus gp90 sequence was tested to see if it facilitated T cell recognition of the more conserved regions early in the infection. Our results indicated that envelope-specific T cell recognition patterns changed over time. Early after infection, dominant immune responses to the peptides in the carboxyl-terminus variable region were identified. By six months post infection, the recognized peptides spanned the entire envelope sequence, with a shift to the amino-terminus conserved region. The mechanisms responsible for this change remain unclear, but analysis of T cell receptor repertoire indicated that T cell clonal expansion and contraction might be one of the reasons. Our demonstration that envelope-specific peptide recognition shifts from the variable to the more conserved regions provides evidence that the maturation of cell mediated immune response is parallelled with long-term control of this infection.

Made available in DSpace on 2016-04-28T20:17:27Z (GMT). No. of bitstreams: 1 2007 - Antonia Regina Sessa da Silva.pdf: 384094 bytes, checksum: 91d2147f8402249dead112e338e89b66 (MD5) Previous issue date: 2007-03-30 / Brazil has currently the second bigger flock of equines of the world and the brazilian equines breeding plays an important role in the development of the sector of agribusiness. Among the infectious disease that affect the national equines breeding, the Equine infectious anemia (EIAV) has been shown of difficult control. The Equine infectious anemia is caused by a retrovirus, it has a worldwide distribution, and it is recognized as the most important disease of equines. The most common clinical signals in the acute phase, are anemia followed of jaundice in the mucosae, ventral oedema, mioglobinury, caquexy and, mainly, intermittent fever. Once it has no treatment, Ministry of Agriculture, Cattle and Supplying determines, through legal mechanisms, a politics of obligatory examination in credentialed laboratories, for the transport and commercialization of equines in the country. The examination is based on the test of Coggins, an immunodiffusion in agar gel (IDGA) of the serum of the animal tested against antigen of the EIAV. As the infection is lifetime, positive animals are euthanasiated by Veterinarians of the Ministry of Agriculture. Considering that precision of the results is critical, once that false positives animals could uselessly be sacrificed, and false negatives will be preserved as infection source, diverse problems may occur, appeared the interest of a systematic analysis of the reproducibility of kits and on possible sources of error. For this purpose, positive and negative sera, referred by the repetition of the tests for Coggins and ELISA, had been evaluated by IDGA comparatively with three kits of different manufacturers. In the experiments of reproducibility, it observed a great distinction in the quality of the precipitation line promoted for the positive sera in the tests. This phenomenon may be justified by the use of the conditions techniques legal, determined for would carry of the Ministry of Agriculture that is distinct of the recommendation of the analyzed manufacturers of two of kits. Exactly thus, the evaluation of the reproducibility of the results of kits with the referred sera showed high correlation. / O Brasil possui atualmente o segundo maior rebanho de eq??deos do mundo e a Eq?ideocultura Brasileira desempenha um importante papel no desenvolvimento do setor de agroneg?cios. Entre as doen?as infecciosas que afetam a eq?inocultura nacional, a Anemia Infecciosa dos Eq?inos (AIE) tem se mostrado de dif?cil controle. A AIE ? causada por um retrov?rus, apresenta uma distribui??o mundial, e ? reconhecida como a mais importante doen?a dos eq?inos. Entre os sinais cl?nicos mais comuns, na fase aguda da doen?a, encontram-se a anemia seguida de icter?cia nas mucosas, edema ventral, mioglobin?ria, caquexia e, principalmente, febre intermitente. Como n?o h? tratamento, Minist?rio da Agricultura, Pecu?ria e Abastecimento (MAPA) determina, atrav?s de mecanismo legais, uma pol?tica de exame obrigat?rio em laborat?rios credenciados, para o transporte e comercializa??o de eq??deos no Pa?s. O exame ? baseado na prova de Coggins, uma imunodifus?o em ?gar gel do soro do animal testado contra ant?geno do v?rus da AIE. Como a infec??o ? vital?cia, animais soropositivos s?o eutanasiados por M?dicos Veterin?rios do MAPA. Considerando que a precis?o dos resultados ? cr?tica, posto que animais falso positivos podem ser sacrificados inutilmente, e falso negativos preservados como fonte de infec??o, surgiu o interesse de um an?lise sistem?tica da reprodutibilidade dos kits e poss?veis fontes de erro no diagn?stico. Para esta finalidade, soros positivos e negativos, referenciados pela repeti??o dos testes de Coggins e ELISA, foram avaliados pela prova de IDGA, comparativamente com tr?s kits de diferentes fabricantes. Nos experimentos de reprodutibilidade, observou-se uma grande distin??o na qualidade da linha de precipita??o promovida pelos soros positivos nos testes nos diferentes kits. Este fen?meno pode ser justificado pela utiliza??o das condi??es t?cnicas legais, determinadas por portaria do MAPA, que s?o distintas das recomenda??es dos fabricantes de dois dos kits analisados. Mesmo assim, a avalia??o da reprodutibilidade dos resultados dos kits com os soros referenciados mostrou elevada correla??o.

Orientador: Luis Antônio Mathias / Resumo: A equideocultura possui grande importância econômica no Brasil, e a anemia infecciosa equina (AIE) representa ameaça para o crescimento do setor. Pouco se sabe sobre análise temporal da ocorrência da doença no Brasil, por isso este trabalho foi conduzido com o objetivo de investigar a frequência e distribuição da anemia infecciosa equina em todo o território brasileiro no período de 2005 a 2016, por meio das análises temporais do índice de morbidade, índice de eliminação de reagentes, razão entre o número de equídeos eliminados e o número de equídeos reagentes, índice de notificação de focos e índice de focos novos e antigos ao longo do período. Foi realizada uma análise de série temporal sobre AIE no período de 2005 a 2016, utilizando dois bancos de dados, o da OIE e o do MAPA. No Brasil, 2010 foi o ano que apresentou o menor índice de morbidade de AIE, com 100,9 casos por 100 mil cabeças, e 2009 apresentou o maior índice, com 159,1 por 100 mil cabeças, e a taxa de variação anual no período foi de -2,4% (-7,5% a 2,8%), revelando estabilidade desse indicador (P = 0,317). O índice de eliminação de reagentes por AIE no Brasil foi maior em 2010, com 62,7 por 100 mil cabeças, e menor em 2016, com 32,1. Durante todo o período estudado, a variação anual no país se mostrou estável, com valor de -6,1% (-18,2% a 7,8%) e valor de P não significativo (0,333). A razão entre o número de equídeos eliminados e o número de equídeos reagentes por 100 equídeos foi baixa em quase todas as UF’s ... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre