Thesis (M.S.)--University of Toledo, 2008. / "In partial fulfillment of the requirements for the degree of Master of Science in Biomedical Sciences." Title from title page of PDF document. Bibliography: pages 82-88, 111-116.

Thesis (Ph. D.)--University of Missouri--Columbia, 1998. / "May 1998." Typescript. Vita. Includes bibliographical references (leaves 172-189). Also available on the Internet.

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 133-160).

Thesis (Ph. D.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xiii, 196 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical reference.

Made available in DSpace on 2015-10-16T12:52:52Z (GMT). No. of bitstreams: 2 renata_barros_ini_mest_2013.pdf: 649069 bytes, checksum: ccf984958e0979b9f8cb5d6df59ab3fd (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2015-06-10 / Fundação Oswaldo Cruz. Instituto de Pesquisa Clínica Evandro Chagas. Rio de Janeiro, RJ, Brasil / A toxoplasmose é uma zoonose causada pelo protozoário Toxoplasma gondii que acomete várias espécies de vertebrados, inclusive o ser humano. Os gatos, assim como os outros felinos, têm papel de suma importância na epidemiologia da infecção, pois são os hospedeiros definitivos do T. gondii. Esse trabalho teve como objetivo determinar a frequência de anticorpos anti-T.gondii associados a fatores de risco e co-infecções em 213 gatos com esporotricose oriundos da região metropolitana do Rio de Janeiro e assistidos no LAPCLIN-DERMZOO, no período de novembro de 2007 a fevereiro de 2011. Esses animais foram acompanhados mensalmente devido ao tratamento para esporotricose, até os seus desfechos clínicos. Foram realizadas sorologias seriadas para toxoplasmose por meio da hemaglutinação indireta (HAI) e pela reação da imunofluorescência indireta (RIFI) e diagnóstico para o feline imunnodeficiency virus (FIV) e o feline leukemia vírus (FeLV) através de um imunoensaio rápido. Dos 213 gatos, 14 (6,6%) apresentaram anticorpos anti-T. gondii na RIFI (IgG) e na HAI. Houve um caso único de soroconversão, no quarto acompanhamento Houve variação de pelo menos dois títulos na IgG-RIFI nos acompanhamentos de dois animais. Apenas um animal (7,1%) apresentou co-infecção de toxoplasmose com o FIV e três animais (21,4%) com o FeLV. Não foi detectada associação entre as variáveis e co-infecções estudadas e a presença de anticorpos anti-T. gondii, porém 78,6% dos gatos com infecção toxoplásmica apresentaram falência terapêutica no tratamento para esporotricose, sendo quatro deles (27,3%) FIV ou FeLV positivos. A frequência da infecção toxoplásmica nos gatos estudados foi baixa, houve uma maior frequência de animais soropositivos para T. gondii entre aqueles que tinham livre acesso a rua, conviviam com outros gatos e possuíam mais de três anos de idade e foi observada 100% de concordância no teste diagnóstico para T. gondii entre a RIFI e a HAI / Toxoplasmosis is a zoonotic disease caused by the Toxoplasma gondii protozoan that affects several species of vertebrates, incl uding human s . Cats, as well as other felines, a re important in the epidemiology of the infection because they are the definite hosts of T . gondii . This study aim ed to determine the frequency of anti - T . gondii antibodies associated with risk factors and coinfections in 213 cats infected with sporotrichosis in the metropolitan Rio de Janeiro and assisted in the LAPCLIN - DERMZOO , in the period of november 2007 to february 2011. These animals were monthly evaluate d due to sporotrichosis treatment until their sporotrichosis treatment outcomes. Serologic series for toxoplasmosis were performed through indirect he magglutination assay (IHA) and indirect fluorescence antibody test (I F A T) , and feline immunodeficiency vi rus (FIV) and feline leukemi a vi rus ( FeLV) diagnose s were made by fast immunoassay. Am ong the 213 studied cats, 14 (6. 6%) showed anti - T. gondii antibodies in the I F A T and in the IHA. There was only one occurrence of seroconversion in the fourth clinical evaluation . There was a variation of at least two titles in the I F A T - IgG in the clinical follow up of two animals. Just one animal (7. 1%) showed coinfection of toxoplasmosis with FIV a nd three animals (21. 4%) with FeLV. The association between variables a nd studied coinfections with the presence of T. gondii antibodies has not been detected, nonetheless 78.6% of the infected cats showed therapeutical failure in the sporotrichosis treatment , and four of them (27. 3%) were FIV or FeLV positive. The frequency of toxoplasmosis infection in the cats was low ; cats that had free access to the street , coexisted with other cats and were older than three years showed a higher rate of T. gondii positivity and a 100% concordance in the diagnostic test for T. gondii between IFAT and IHA was also observed.

Made available in DSpace on 2016-03-04T13:59:26Z (GMT). No. of bitstreams: 2 luciana_barros_ioc_dout_2014.pdf: 3326577 bytes, checksum: 370ee3d6142f8100a7adc37a80899e9a (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2016-01-13 / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil / O timo é um órgão linfoide primário, sítio do desenvolvimento de células T, provendo fatores críticos e coordenados que induzem e suportam o comprometimento de linhagem, diferenciação e sobrevivência dessas células. A presença das células não-linfóides, principalmente as células epiteliais do timo (TEC) no parênquima tímico promove a migração e diferenciação coordenada dos linfócitos T. Os linfócitos T são o principal alvo do Virus linfotrópico T humano (HTLV-1), agente etiológico da leucemia/linfoma associado ao HTLV-1 (ATL) e de doença que compromete o sistema nervoso/muscular (HAM/TSP). É desconhecida a causa que leva a uma ou outra doença. A resposta imune antiviral mediada por células T é ineficiente nessas patologias. Mesmo que o vírus tenha tropismo pelos linfócitos T, ele é capaz de infectar outros tipos celulares por contato direto entre células ou por partículas virais livres. Linfócitos ativados recirculam pelos órgãos linfoides, incluindo o timo, onde as células epiteliais tímicas (TEC) interagem intimamente com as células recirculantes, promovendo uma possível via de transmição do HTLV-1. No nosso trabalho, observamos que as TECs possuem os receptores para a entrada do vírus (GLUT-1 e Neuropilina-1). Experimentos in vitro mostraram que as TECs podem ser infectadas pelo HTLV-1 por linhagens de linfócitos derivados de pacientes portadores de ATL e de HAM/TSP Essas infecções ocorreram tanto por contato direto entre as células, quanto por sobrenadante contendo partículas virais livres derivadas do sobrenadante dos linfócitos. O vírus pode ser observado após 24 horas e 10 dias de cultivo, quando a maioria das células estava infectada. Através de microscopia eletrônica de transmissão, foram observadas partículas virais brotando de estruturas semelhantes a corpos multivesculares nas TECs. A expressão gênica de citocinas e quimiocinas foram encontradas aumentadas nas TECs logo após contato com o sobrenadante contendo HTLV-1 derivado dos linfócitos. Somado a isso, a expressão gênica de inteferon tipo 1 e genes induzidos por interferon estavam diminuídos. A resposta migratória de linfócitos T CD4+ induzida por TEC HTLV-1+ estava aumentada em relação as TEC não-infectadas. As TEC infectadas são capazes de transmitir a infecção para linfócitos T por contato, alterando a expressão de receptores de quimiocinas e de adesão nos linfócitos T CD4+. Juntos, esses resultados sugerem que as TEC HTLV-1+ infectadas por linfócitos infectados ou por vírus livres, transmitem a infecção para outras TECs e para linfócitos T CD4+, disseminando a infecção / The thymus is a primary lymphoid organ, site of developing T cells, providing a coordinated set of critical factors to induce and support lineage commitment, di fferentiation and survival of these cells. The presence of non - lymphoid cells through the thymic parenchyma serves to provide coordinated migration and differentiation of T lymphocytes. T lymphocytes are the main target of Human T Lymphotropic Virus type 1 (HTLV - 1). This virus is the etiologic agent of HTLV - 1 associated lymphoma and leukemia (ATL) or a disease of muscular/nervous systems (HAM/TSP), but it is unknown what triggers to one or other disease. T - cell mediated immune response against viral protein s is not effective in both diseases. Although the virus has T lymphocyte tropism, it can infect other cells by cell contact and cell - free virus. Activated T lymphocytes circulates around lymphoid organs, including the thymus, where the thymic epithelial ce lls (TEC) strongly interact with recirculating cells, so infected lymphocytes could transmit the virus to TEC. Interestingly, in our work we observed that TEC expresses molecules related to the HTLV - 1 transmission (GLUT - 1, Neuropilin 1). In vitro experimen ts showed that TEC could be infected by cell lineages derived from ATL and HAM/TSP patients. These infections happened from cell contact and by cell - free virus derived from cell supernatants. The virus can be seen after 24h and after 10 days, when most cel ls in the culture were infected. By transmission electron microscopy, virus particles were observed budding from multivesicular bodies like structures in TEC. Cytokines and chemokines were incr eased at mRNA level soon after contact with HTLV - 1 containing supernatant derived from lymphocytes. In addition, type 1 interferon and interferon stimulated genes were decreased in HTLV - 1 infected TEC. Migration response from T CD4 + lymphocytes driven by H TLV - 1 + TEC were increased in relation to non - infected TEC. HTLV - 1 + TEC could transmit the infection to T CD4 + lymphocytes by cell contact, altering some chemokines and adhesion receptors in T CD4 + cells. Altogether, these results suggest that after TEC inf ection by HTLV - 1 via infected lymphocytes and cell - free virus, it is able to contaminate another TEC and transmit the virus to non - infected T lymphocytes, disseminating the infection.

O vetor retroviral é uma ferramenta de transferência gênica largamente utilizada em ensaios de laboratório e em protocolos clínicos. Nosso laboratório desenvolveu um novo vetor, chamado pCLPG, com expressão viral sob comando de p53, um supressor de tumor e um ativador indutível de transcrição, com alvo de estabelecer um vetor com alta expressão. O sistema pCLPG demonstrou um nível de expressão superior ao vetor não modificado em ensaios em cultura de células. Neste projeto, nosso objetivo foi caracterizar a expressão do vetor pCLPG in vivo, utilizando um modelo animal de transdução de células da medula óssea (CMO) do camundongo C57BL/6 seguido por transplante em animais recipientes previamente irradiados para abolir o sistema hematopoiético. Visando observar a expressão sustentada do transgene in vivo, padronizamos o transplante de CMO seriado, transdução do vetor retroviral, realizamos análise do gene repórter eGFP por citometria de fluxo e análise por real time PCR, além da observação de outros tecidos como baço, timo, sangue periférico. Realizamos também analises hematológicas nos animais transplantados para observação de possíveis efeitos adversos relacioanados com a presença do retrovírus. Com estes ensaios não foi observado uma diferença significante entre o desempenho do vetor parental pCLeGFP e o pCLPGeGFP. Tanto o número de células eGFP positivas quanto a expressão do gene repórter diminuíram ao longo do processo de transplante seriado. Expressão foi observada em 3-4%, 2-3% ou 2-3% das celulas recuperadas da medula ossea dos recipientes primários, secundários ou terciários de CMO transduzida com o vetor pCLeGFP, mas não no sangue periférico, timo ou baço. Semelhantemente, células eGFP-positivas (6-7%, 4-4,5% ou 3-3,5%) foram observadas após transplante seriado somente na medula óssea de animais recipientes de CMO transduzida com o vetor pCLPGeGFP. Entretanto, sangue periférico foi recuperado dos recipientes e tratado com 5-asacitidina, proporcionando a indução de expressão de eGFP a partir de ambos os vetores em aproximadamente 4% das células, implicando que o silenciamento viral poderia estar relacionado com processos de metilação. Este estudo demonstrou que as modificações no promotor do vetor pCLPG não foram suficientes para evitar silenciamento de expressão viral no modelo utilizado. / The retroviral vector is a widely used gene transfer tool in both laboratory assays and clinical trials. Our laboratory developed a new vector, called pCLPG, with viral expression under the command of p53, a tumor suppressor and inducible activator of transcription, with the aim of establishing a vector with high level expression. The level of expression offered by the pCLPG system was superior to the non-modified vector in cell culture assays. In this project, our objective was to characterize the expression of the pCLPG vector in vivo utilizing an animal model where bone marrow cells (BMC) from C57BL/6 mice are transduced and then transplanted in recipient animals that have been previously irradiated in order to abolish the hematopoietic system. With the aim of observing sustained transgene expression in vivo, we standardized serial BMC transplantation, transduction with retroviral vectors and analyzed the eGFP reporter gene by flow cytometry and real time PCR, and also studied other tissues, such as spleen, thymus and peripheral blood. We also performed hematologic analyses in the transplanted animals in to observe possible adverse events related to the presence of the retrovirus.These assays did not reveal a significant difference between the performances of the parental pCLeGFP vector and pCLPGeGFP. Both the number of eGFP-positive cells and the intensity of reporter gene expression diminished during the serial transplant process. Expression was observed in 3-4%, 2-3% or 2-3% of cells recovered from bone marrow of the primary, secondary or terciary recipients of BMC transduced with the pCLeGFP vector, but not in peripheral blood, thymus or spleen. Similarly, eGFP-positive cells (6-7%, 4-4.5% or 3-3.5%) were observed after serial transplantation only in the bone marrow of animals that received BMC transduced with the pCLPGeGFP vector. However, peripheral blood was recovered from recipients and treated with 5-azacytidine, inducing the expression of eGFP from both vectors in approximately 4% of these cells, implying that viral silencing may have been related with methylation. This study demonstrated that the modifications in the promoter of the pCLPG vector were not sufficient to avoid silencing of viral expression in this model.

O vetor retroviral é uma ferramenta de transferência gênica largamente utilizada em ensaios de laboratório e em protocolos clínicos. Nosso laboratório desenvolveu um novo vetor, chamado pCLPG, com expressão viral sob comando de p53, um supressor de tumor e um ativador indutível de transcrição, com alvo de estabelecer um vetor com alta expressão. O sistema pCLPG demonstrou um nível de expressão superior ao vetor não modificado em ensaios em cultura de células. Neste projeto, nosso objetivo foi caracterizar a expressão do vetor pCLPG in vivo, utilizando um modelo animal de transdução de células da medula óssea (CMO) do camundongo C57BL/6 seguido por transplante em animais recipientes previamente irradiados para abolir o sistema hematopoiético. Visando observar a expressão sustentada do transgene in vivo, padronizamos o transplante de CMO seriado, transdução do vetor retroviral, realizamos análise do gene repórter eGFP por citometria de fluxo e análise por real time PCR, além da observação de outros tecidos como baço, timo, sangue periférico. Realizamos também analises hematológicas nos animais transplantados para observação de possíveis efeitos adversos relacioanados com a presença do retrovírus. Com estes ensaios não foi observado uma diferença significante entre o desempenho do vetor parental pCLeGFP e o pCLPGeGFP. Tanto o número de células eGFP positivas quanto a expressão do gene repórter diminuíram ao longo do processo de transplante seriado. Expressão foi observada em 3-4%, 2-3% ou 2-3% das celulas recuperadas da medula ossea dos recipientes primários, secundários ou terciários de CMO transduzida com o vetor pCLeGFP, mas não no sangue periférico, timo ou baço. Semelhantemente, células eGFP-positivas (6-7%, 4-4,5% ou 3-3,5%) foram observadas após transplante seriado somente na medula óssea de animais recipientes de CMO transduzida com o vetor pCLPGeGFP. Entretanto, sangue periférico foi recuperado dos recipientes e tratado com 5-asacitidina, proporcionando a indução de expressão de eGFP a partir de ambos os vetores em aproximadamente 4% das células, implicando que o silenciamento viral poderia estar relacionado com processos de metilação. Este estudo demonstrou que as modificações no promotor do vetor pCLPG não foram suficientes para evitar silenciamento de expressão viral no modelo utilizado. / The retroviral vector is a widely used gene transfer tool in both laboratory assays and clinical trials. Our laboratory developed a new vector, called pCLPG, with viral expression under the command of p53, a tumor suppressor and inducible activator of transcription, with the aim of establishing a vector with high level expression. The level of expression offered by the pCLPG system was superior to the non-modified vector in cell culture assays. In this project, our objective was to characterize the expression of the pCLPG vector in vivo utilizing an animal model where bone marrow cells (BMC) from C57BL/6 mice are transduced and then transplanted in recipient animals that have been previously irradiated in order to abolish the hematopoietic system. With the aim of observing sustained transgene expression in vivo, we standardized serial BMC transplantation, transduction with retroviral vectors and analyzed the eGFP reporter gene by flow cytometry and real time PCR, and also studied other tissues, such as spleen, thymus and peripheral blood. We also performed hematologic analyses in the transplanted animals in to observe possible adverse events related to the presence of the retrovirus.These assays did not reveal a significant difference between the performances of the parental pCLeGFP vector and pCLPGeGFP. Both the number of eGFP-positive cells and the intensity of reporter gene expression diminished during the serial transplant process. Expression was observed in 3-4%, 2-3% or 2-3% of cells recovered from bone marrow of the primary, secondary or terciary recipients of BMC transduced with the pCLeGFP vector, but not in peripheral blood, thymus or spleen. Similarly, eGFP-positive cells (6-7%, 4-4.5% or 3-3.5%) were observed after serial transplantation only in the bone marrow of animals that received BMC transduced with the pCLPGeGFP vector. However, peripheral blood was recovered from recipients and treated with 5-azacytidine, inducing the expression of eGFP from both vectors in approximately 4% of these cells, implying that viral silencing may have been related with methylation. This study demonstrated that the modifications in the promoter of the pCLPG vector were not sufficient to avoid silencing of viral expression in this model.

Human endogenous retroviruses are the remnants of ancient retroviral infections present within our genome. These molecular fossils show similarities with present day exogenous retroviruses but act as typical Mendelian elements that are passed vertically between generations. Despite being repeatedly linked to a number of autoimmune diseases and disorders, no conclusive proof has been identified. Rheumatoid arthritis (RA) is one such disease which has been associated with an increase in HERV expression, compared to controls. In order to elucidate a clear role for HERVs in RA pathogenesis, autoantigens implicated in disease pathogenesis were scanned for sequence homology to retroviral genes. Such epitopes would induce antibodies cross reactive with host proteins, resulting in disease. Short peptides mimicking these regions were synthesised and the prevalence of anti-HERV antibodies was determined in RA patients and disease controls. Additionally, a novel real-time Polymerase Chain Reaction (PCR) assay was developed to accurately quantify levels of HERV-K (HML-2) gag expression, relative to normalised levels of housekeeping gene expression. Both serological and molecular assays showed significant increases in HERV-K (HML-2) activity in RA patients compared to disease controls with CD4+ lymphocytes harbouring the highest activity. The real-time assay was also used to determine whether factors within the synovium could modulate HERVs, resulting in their upregulation. Exogenous viral protein expression and pro-inflammatory cytokines were shown to exert a significant modulatory effect over HERV-K (HML-2) transcription. From this data, it is clear that RA patients have increased levels of HERV-K (HML-2) gag activity compared to controls. Despite this it is likely that factors within the synovium such as exogenous viral expression and pro-inflammatory cytokines also influence HERV-K (HML-2) transcription possibly contributing to a role of bystander activation, i.e. being influenced by external factors, rather than actively contributing to disease processes. The exact role of HERVs in RA pathology remains elusive; however this research proposes several mechanisms by which HERV-K (HML-2) may contribute to disease.

<p>The studies in the present thesis sought to define virus and host factors that can influence on the susceptibility to murine retrovirus infection. In addition, we wanted to study possible correlations between events of early infection and subsequent disease progression. For an extensive discussion of the major findings, the reader is referred to papers I-IV. The following section will give a general discussion concerning 1) some methodological aspects; 2) the course of FIS-2 infection; 3) determinants responsible for erythroleukaemia; 4) determinants responsible for immunosuppression; and, 5) does sex matter?</p>