Deux grandes classes de cellules composent le pool de lymphocytes T (LT) CD8 mémoires. D'une part, les LT CD8 mémoires conventionnels sont générés via la reconnaissance spécifique d'antigènes dérivés de pathogènes ou de tumeurs. D'autre part, les LT CD8 mémoires innés sont générés via différents mécanismes impliquant de fortes stimulations par des cytokines γc indépendamment de la reconnaissance d'antigènes du non soi. Le phénotype extrêmement similaire de ces deux populations cellulaires ne permet pas de les distinguer in vivo. En conséquence, la population de LT CD8 mémoires innés est relativement peu caractérisée. Mon travail de thèse comportait donc deux objectifs majeurs : 1 / Identifier des marqueurs permettant de distinguer in vivo ces deux classes de LT CD8 mémoires. 2/ Caractériser la population de LT CD8 mémoires innés. Dans cette étude, nous démontrons qu'au sein du pool de LT CD8 mémoires, seules les cellules conventionnelles expriment la chimiokine CCL5 et le récepteur NKG2D. Ces deux biomarqueurs permettent ainsi pour la première fois de distinguer les LT CD8 mémoires innés et conventionnels in vivo, à la fois chez la souris et chez l'homme. Grâce à l'expression de NKG2D, nous démontrons que ces LT CD8 mémoires innés possèdent des caractéristiques typiques de cellules mémoires, notamment une réactivité augmentée ainsi qu'un programme génétique comparable à celui des LT CD8 mémoires conventionnels. Néanmoins, cette population cellulaire conserve certaines caractéristiques de cellules naïves. Ainsi, le répertoire TCR diversifié de cette population cellulaire permet à ces cellules de participer à des réponses immunitaires primaires contre différents pathogènes. Enfin, dans un contexte inflammatoire, les LT CD8 mémoires innés présentent un défaut d'accès au tissu pulmonaire comparé aux LT CD8 mémoires conventionnels. Ceci corrèle avec un déficit d'expression de certaines intégrines par les LT CD8 mémoires innés. L'ensemble de nos résultats démontre que les LT CD8 mémoires innés, caractérisés par l'absence d'expression de CCL5 et NKG2D, constituent une population cellulaire hybride, à la frontière entre cellules naïves et cellules mémoires conventionnelles / The pool of memory CD8 T cells is composed of two major cell classes. On one hand, conventional memory CD8 T cells are generated consequently to the specific recognition of pathogen or tumor derived antigens. On the other hand, innate memory CD8 T cells are generated through several mechanisms involving strong yc cytokine stimulation in the absence of cognate antigen recognition. However, these cell classes harbor a very similar phenotype. As a consequence, innate memory CD8 T cell population remains poorly characterized. This PhD has two main objectives : 1 / Identify new biomarkers that enable the discrimination between memory CD8 T cell classes 2/ Characterize the population of innate memory CD8 T cells in physiological condition Our results show that among the pool of memory CD8 T cells, only the conventional ones express the chemokine CCL5 and the NK receptor NKG2D. These two biomarkers enable for the first time the discrimination of memory CD8 T cell classes in physiological settings, in both mouse and human. Thanks to these new tools, we show that innate memory CD8 T cells hold typical memory features, such as an increased reactivity compared to naïve cells and a genetic program similar to the one of conventional memory cells. Nevertheless, this cell population also retains some features typical of naïve cells. The diversified TCR repertoire of this cell population allows it to participate to primary immune responses against various intracellular pathogens. Moreover, like naïve cells, innate memory CD8 T cells fail to access peripheral tissues upon local inflammation, which correlate with an absence of expression of some integrins. Altogether, these results demonstrate that innate memory CD8 T cells, characterized by the absence of expression of CCL5 and NKG2D, represent a hybrid cell population, at the boundary between naïve cells and conventional memory cells

Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-11-27T17:43:41Z No. of bitstreams: 1 Marta Belfort.pdf: 1659970 bytes, checksum: 7aca8a1f671f32a3e25959a2840b065f (MD5) / Made available in DSpace on 2017-11-27T17:43:41Z (GMT). No. of bitstreams: 1 Marta Belfort.pdf: 1659970 bytes, checksum: 7aca8a1f671f32a3e25959a2840b065f (MD5) Previous issue date: 2017-08-28 / FAPEMA,CNPQ. / Penile cancer (PeCa) is a rare neoplasm in developed countries; however, its incidence is high in underdeveloped countries. In Brazil, regions North and Northeast are those with the higher number of cases for the disease. Among the factors associated with this neoplasm we highlight: poor hygiene, phimosis, chronic inflammation and infection by human papilloma virus (HPV). Changes in the PI3K/AKT/PTEN cell signaling pathway have been reported for several malign neoplasms, but little is known about the involvement of this pathway in penile tumors. Thus, the aim of this study was to verify the role of HPV infection and the occurrence of copy number alterations (CNA) in genes from the signaling pathway mediated by receptors of growth factors and PI3K in a population characterized by advanced tumors and high frequency of high risk HPV. To achieve that, we collected tumor tissue samples (both fresh and in formalin-fixed paraffin-embedded tissue-FFPE) from 34 patients from two reference hospitals: Instituto Maranhense de Oncologia Aldenora Belo (IMOAB) and the Hospital Universitário Presidente Dutra from the Universidade Federal do Maranhão (HU-UFMA). Fresh tumors were submitted to detection and genotyping of HPV by Nested PCR (Polymerase Chain Reaction) and direct sequencing. CNA analyzes were carried out in FFPE tissue from a subgroup HPV positive (91.2%), of which 88.2% were at high oncogenic risk. TaqMan® Copy Number Assays (Life TechnologiesTM) and CopyCaller software version v2.0 were performed to determine copy number for EGFR, HER3, HER4, AKT1, AKT2, PI3KCA and PTEN. Increase of 3 and 4 copies was considered gains, while increase of 5 or more copies was considered amplifications. The presence of a single gene copy was referred to as loss, while the absence of two copies was named deletion. Clinical and histopathological parameters were analyzed as to the presence of HPV and to CNAs. Our data showed that EGFR/PI3K/AKT/PTEN signaling pathway is highly altered in PeCa. The results showed that 100% of the tumors presented an increase of the number of copies for HER3; out of those, 93.9% were amplified, with 84.4% having 10 or more copies. EGFR also showed an increase of copies in 87.8% of tumor samples, out of which 65.6% were amplifications, with 48.2% having more than 10 copies. Furthermore, HER4 and AKT1 also presented an increase in the number of copies of 20.6% and 15%, respectively. AKT1 had a higher frequency of tumors with a regular number of copies (78.8%). On the other hand, PI3KCA, HER4, PTEN and AKT2 presented a higher frequency of samples with deletions, presenting 56%, 52.9%, 39% and 36%, respectively. Loss of copies was also frequent on tumors, so that genes AKT2, PTEN and PI3KCA appeared in heterozygosis in 60.6%, 54.5% and 37.5%, respectively. Our data show the occurrence of genetic alterations that may justify the differential expression of growth factor receptors and the downstream genes of the PI3K/ AKT pathway in penile carcinoma. However, in this study there was no association between CNAs and clinical and histopathological variables. On the other hand, taking into consideration the high frequency of HPV in the evaluated tumors, we suggest that CNAs are related to HPV integration into genome host. Finally, we highlight the high frequency of tumors with amplifications in HER3 and EGFR, reinforcing these markers as targets for specific therapies in CaPe. / Câncer de pênis (CaPe) é uma neoplasia rara em países desenvolvidos, entretanto, sua incidência é elevada em países subdesenvolvidos. No Brasil, as regiões Norte e Nordeste são as regiões com os maiores números de casos da doença. Dentre os fatores de risco, destaca-se a má higiene do órgão genital, fimose, inflamação crônica e infecção pelo papilomavírus-humano (HPV). Tem sido reportada alterações na via de sinalização celular PI3K/AKT/PTEN em diversas neoplasias malignas, entretanto, pouco se sabe sobre o envolvimento dessa via nos tumores de pênis. Assim, buscou-se neste trabalho verificar o papel da infecção por HPV e a ocorrência de alteração no número de cópias (CNAs) em genes da via de sinalização controlada por receptores dos fatores de crescimento e PI3K, em uma amostra caracterizada por tumor avançado e alta frequência de HPV de alto risco. Para isso, foram coletadas amostras de tecido tumoral (fresco e de tecido fixado com formalina e embebido em parafina - FFPE) de 34 pacientes provenientes de dois hospitais de referência, Instituto Maranhense de Oncologia Aldenora Belo (IMOAB) e o Hospital Universitário Presidente Dutra da Universidade Federal do Maranhão (HU-UFMA). As amostras de tumor fresco foram submetidas a detecção e genotipagem de HPV por Nested PCR (Polymerase Chain Reaction) e sequenciamento direto. As análises de CNAs foram realizadas em amostras de FFPE, HPV positivas (91,2%), das quais 88,2% eram de alto risco oncogênico. Utilizou-se o ensaio TaqMan® Copy Number Assays (Life TechnologiesTM) e o software CopyCaller versão 2.0 para determinação do número de cópias dos genes EGFR, HER3, HER4, AKT1, AKT2, PIK3CA e PTEN. Aumento de 3 e 4 cópias foi considerado ganho, enquanto aumento de 5 ou mais cópias foi considerado amplificação. A presença de uma única cópia gênica foi nomeada perda, enquanto a ausência de duas cópias foi nomeada deleção. Os parâmetros clínicos e histopatológicos foram analisados quanto a presença de HPV e também quanto a CNAs. A via de sinalização celular EGFR/PI3K/AKT/PTEN revelou-se altamente alterada nos tumores de pênis. Observou-se que 100% dos tumores apresentaram aumento de número de cópias do gene HER3. Destes, 93,9% apresentaram-se amplificados, sendo que 84,4% apresentavam 10 ou mais cópias. O gene EGFR apresentou aumento de cópias em 87,8% das amostras, das quais 65,6% eram amplificações, sendo que 48,2% apresentavam mais de 10 cópias. Além desses, os genes HER4 e AKT1 também apresentaram aumento de cópias gênicas, em 20,6% e 15%, respectivamente. AKT1 apresentou maior porcentagem de tumores com número normal de cópias (78,8%). Por outro lado, os genes PI3KCA, HER4, PTEN e AKT2 apresentaram maiores frequências de amostras com deleções, com 56%, 52,9%, 39% e 36%, respectivamente. As perdas também foram frequentes nos tumores, de modo que os genes AKT2, PTEN e PI3KCA apresentaram-se em heterozigose em 60,6%, 54,5% e 37,5%, respectivamente. Nossos dados mostram a ocorrência de alterações genéticas que podem justificar a expressão diferencial dos receptores de fatores de crescimento e de genes downstream da via PI3K/AKT em carcinoma peniano. No entanto, não foi encontrada associação entre CNAs e as variáveis clínicas e histopatológicas. Por outro lado, considerando-se a alta frequência de HPV nos tumores avaliados, levanta-se a possibilidade de haver uma relação entre a integração do HPV no genoma do hospedeiro e a ocorrência de CNAs em CaPe. Finalmente, destacamos a alta frequência de tumores com amplificações em HER3 e EGFR, abrindo a possibilidade desses marcadores serem utilizados como alvos para terapias específicas em CaPe.

É grande a preocupação na identificação de compostos envolvidos no desenvolvimento de processos deletérios, como o câncer. O tetraidrofurano (THF) é um solvente amplamente utilizado em indústria e pesquisa e estudos recentes indicaram uma atividade carcinogênica em animais experimentais, incentivando a investigação da sua possível interação com biomoléculas. Adutos de DNA servem como marcadores para a identificação da atividade genotóxica de substâncias e para o monitoramento da exposição humana aos agentes genotóxicos. Estudos realizados in vitro, em células em cultura, bem como em animais experimentais, permitem que mecanismos sejam desvendados e metodologias sejam desenvolvidas para uma posterior avaliação da exposição humana. O contínuo desenvolvimento de técnicas de análise de adutos em DNA para monitoramento biológico constitui importante preocupação para pesquisadores envolvidos com a saúde ocupacional e a medicina preventiva. No presente trabalho foi investigada a reação de produtos de oxidação do THF com os nucleosídeos 2\'-desoxiadenosina (dAdo) e 2\'-desoxicitidina (dCyd). As estruturas dos adutos formados foram elucidadas por análises de espectros de massas (ESI/MS-MS) e ressonância magnética nuclear (RMN) após purificação de quantidade suficiente dos produtos por cromatografia líquida de alta eficiência (HPLC). Com isso, foi aberta a possibilidade de validação de novos marcadores de exposição a THF. Tais lesões foram detectadas em DNA incubado com THF oxidado in vitro, após o desenvolvimento de uma metodologia sensível e seletiva baseada em HPLC/ESI/MS-MS. Além disso, camundongos foram expostos a vapor de THF e foi feita análise de dano oxidativo (8-oxo-2-desoxiguanosina) no DNA de fígado e rim. Um aumento de aproximadamente oito vezes no nível de 8-oxo-2-desoxiguanosina foi observado no DNA dos órgãos dos camundongos expostos ao THF. Nossos estudos in vitro apontam para a possibilidade de ação genotóxica do THF oxidado (formação de adutos com o DNA). A ocorrência dessa via in vivo será investigada em estudos posteriores. Adicionalmente, há aumento de dano oxidativo em órgãos alvos de carcinogênese induzida por esse solvente. / There is a huge concern to identify compounds involved in the development of harmful processes, like cancer. Tetrahydrofuran (THF) is a solvent widely used in industries and recent researches and studies indicated a carcinogenic activity in experimental animals, instigating the investigation of its possible interaction with biomolecules. DNA adducts are used as markers for the identification of genotoxic activity of substances and monitoring the human exposition to genotoxic agents. Studies carried out in vitro, in culture cells and in experimental animals allow to disclose mechanisms and develop methodologies for a posterior evaluation of the human exposition. The continuous development of techniques for the analysis of DNA adducts for biological monitoring constitutes a remarkable concern for the researchers involved with occupational health and preventive medicine. In the present paper, the reaction of THF oxidation products with the nucleosides 2\'-deoxyadenosine (dAdo) and 2\'-deoxycitidine (dCyd) were investigated. The structures of the formed adducts were elucidated by mass spectra analysis (ESI/MS-MS) and nuclear magnetic resonance (RMN) after purification of sufficient quantities of the products by high-performance liquid chromatography (HPLC). Thus, the validation of new markers of exposition to THF was made possible. Such damages were detected in DNA incubated with oxidized THF in vitro, after the development of a sensible and selective methodology based on HPLC/ESI/MS-MS. Moreover, mice were exposed to THF vapors and an oxidative damage analysis (8-oxo-2\'-deoxyguanosine) was carried out on DNA from liver and kidney. An approximate 8-fold increase in the level of 8-oxo-2\'-deoxyguanosine was observed on DNA from the mices organs exposed to THF. Our in vitro studies indicate the possibility of oxidized THF genotoxic action (formation of adducts with DNA). The occurrence of this path in vivo will be investigated in future studies. In addition, the oxidative damage in target organs of carcinogenesis induced by this solvent was increased.

Made available in DSpace on 2017-07-10T14:57:34Z (GMT). No. of bitstreams: 1 Jardel_ Nimet.pdf: 1924881 bytes, checksum: 4755b41b1458253b217679d76b6eeead (MD5) Previous issue date: 2016-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Abstract: This study evaluated the use of gill and liver of Astyanax bifasciatus as histological biomarkers for biomonitoring of streams with different uses and land occupation. The fish were collected by electric fishing technique, in six streams classified as afforested, rural and urban, in the basin of the lower Iguaçu River, west region of Paraná State, in December 2014. It was tested the hypothesis that in streams that are influenced by effluents from urban and rural areas occur greater number and histopathological severity in gill and liver of A. Bifasciatus. In this context, the objective of this study was to correlate the presence and degree of histopathology of gill and liver with the environmental variables among streams with different uses and land occupation. The environments considered afforested showed higher values of dissolved Oxygen (DO) and lower conductivity (CO) when compared to the rural and urban environments. The gills of fish from the afforested streams indicated normal functioning of the organ, while in the rural and urban streams, the histopathology in the gills suggested light to moderate damage to the organ. In relation to the liver, the histopathology indicated light to moderate damage in rural streams and moderate to severe damage in urban streams. When considering the abiotic variables and frequencies of histopathology of gill and liver, the afforested streams were separated from rural and urban areas. The histopathology in gills and livers were significantly more severe, corroborating our hypothesis. It was possible to distinguish streams with different uses and land occupation, therefore, these histopatologias showed favorable biomarkers for studies of biomonitoring / Resumo: Este estudo avaliou o uso de brânquia e fígado de Astyanax bifasciatus como biomarcadores histológicos para biomonitoramento de riachos com diferentes usos e ocupação do solo. Os peixes foram coletados por meio da técnica de pesca elétrica, em seis riachos classificados em florestados, rurais e urbanos, na bacia do baixo Rio Iguaçu, região Oeste do Estado do Paraná, em dezembro de 2014. Testou-se a hipótese de que em riachos que sofrem influências de efluentes oriundos de áreas rurais e urbanas ocorrem maior número e severidade histopatológicas em brânquia e fígado de A. bifasciatus. Nesse contexto, este estudo teve como objetivo correlacionar a presença e o grau de histopatologias de brânquia e fígado com as variáveis ambientais entre riachos com diferentes usos e ocupação do solo. Os ambientes considerados florestados apresentaram maiores valores de Oxigênio dissolvido (OD) e menores de condutividade (CO) quando comparados com os ambientes rurais e urbanos. As brânquias dos peixes dos riachos florestados indicaram funcionamento normal do órgão, enquanto que nos riachos rurais e urbanos, as histopatologias nas brânquias sugeriram danos leves para moderados ao órgão. Em relação ao fígado as histopatologias indicaram danos leves para moderados nos riachos rurais e danos moderados para severos nos riachos urbanos. Ao considerar as variáveis abióticas e as frequências das histopatologias de brânquia e fígado, os riachos florestados foram separados dos rurais e urbanos. As histopatologias nas brânquias e fígados foram significativamente mais severas, corroborando a nossa hipótese. Foi possível distinguir os riachos com diferentes usos e ocupação do solo, portanto, essas histopatologias se mostraram biomarcadores favoráveis para estudos de biomonitoramento

A tuberculose (TB) é uma doença infecciosa bacteriana causada por Mycobacterium tuberculosis (Mtb), acomete seres humanos em todo mundo, e é considerada uma das principais causas de morbidade e mortalidade dentre as doenças infecciosas. Nesse cenário, a TB ainda é vista como um grande desafio para a ciência e para medicina. Com o estudo de novos alvos moleculares para terapia e diagnóstico, por exemplo, a sinalização Notch tem sido descrita como uma via importante para a manutenção da resposta imunológica durante a infecção por Mtb. Assim, o objetivo deste trabalho foi avaliar a participação da via Notch na modulação da resposta imune durante a infecção por Mtb em humanos. Neste trabalho foram incluidos 13 pacientes com tuberculose ativa e 13 indivíduos saudáveis. Células mononucleares de sangue periférico (PBMCs) foram isoladas e avaliadas quanto à expressão de receptores Notch 1 - 2 em células T e ligantes Notch, DLL1 - 4 em subpopulações de monócitos por citometria de fluxo e expressão de genes relacionados à via Notch e resposta imune. Além disso, o plasma foi utilizado para avaliar níveis de citocinas, CD14s e CD163s. Ainda, avaliamos a função celular dependente da ativação da via Notch durante a infecção de células mononucleares de sangue periférico de indivíduos saudáveis com Mtb H37Rv in vitro. Observamos que pacientes com TB ativa apresentaram aumento na expressão de DLL4 em monócitos intermediários e não-clássicos e diminuição na expressão de Notch 2 em células T CD8+. In vitro, observamos nas culturas de PBMCs, aumento da expressão de DLL4 em monócitos intermediários e Notch 2 em células T CD4+. A expressão do ligante DLL4 em monócitos intermediários e a expressão do Notch 1 em células T CD4+ em pacientes com TB ativa se correlacionaram positivamente com o grau de lesão pulmonar. Além disso, pacientes com quadros de lesão pulmonar moderado e avançado têm maior expressão de Notch 1 em células T CD4+ quando comparados a pacientes com grau mínimo de lesão pulmonar. Pacientes com TB ativa apresentam aumento significativo nos níveis plasmáticos de IL-6, IP- 10, CD14s e CD163s e diminuição nos níveis de IFN-?, IL-17A, IL-4, IL-2, IL-1? e RANTES. Os níveis plasmáticos de IFN-?, TNF-?, IL-17A, IL-4, IL-2, IL-12, IL-1?, RANTES e IL-10 se correlacionaram positivamente com o maior grau de lesão pulmonar.Além disso, demonstramos que os níveis de IFN-?, IL-17A, IL-1?, IL-4 e IL-2 se relacionam com maior expressão do receptor Notch 1 em células T CD4+ , enquanto níveis plasmáticos de IP-10, CD163s e de procalcitonina se correlacionam com maior expressão de Notch 1 em células T CD8+. Evidenciamos maior tendência na expressão de HES1 em pacientes com TB ativa e células infectadas in vitro, indicando que a via Notch está sendo ativada durante a infecção por Mtb. De forma interessante, in vitro as culturas de PBMCs tratadas com inibidor farmacológico da via Notch (GSI), reduziram a produção de IL-17A, IL-2 e IL-10 e aumentaram IL-8, enquanto o tratamento com anti-hDLL4 promoveu o aumento significativo nos níveis de TNF-? e atividade fagocítica de monócitos. Em conclusão, a expressão de receptores e ligantes Notch é alterada durante a TB, em especial o ligante DLL4 em subpopulações de monócitos. Além disso, a via Notch parece ser importante na modulação de respostas pró e anti-inflamatórias. Nesse trabalho, sugerimos que a expressão de Notch 1 em células T e DLL4 em subpopulações de monócitos estão associados com a gravidade da TB. Assim, a detecção desses constituintes da via Notch em PBMCs de pacientes com TB ativa são potenciais biomarcadores para avaliar a progressão da doença. / Tuberculosis (TB) is a bacterial infectious disease caused by Mycobacterium tuberculosis (Mtb), affects humans worldwide, and is considered a major cause of morbidity and mortality among infectious diseases. In this scenario, TB is still seen as a major challenge for science and medicine. With the study of new molecular targets for therapy and diagnosis, for example, Notch signaling has been described as an important pathway for the maintenance of immune response during Mtb infection. Thus, the objective of this work was to evaluate the participation of the Notch pathway in the modulation of the immune response during Mtb infection in humans. In this study, 13 patients with active tuberculosis and 13 healthy individuals were included. Peripheral blood mononuclear cells (PBMCs) were isolated and evaluated for Notch 1 - 2 receptor expression in T cells and Notch, DLL1 - 4 ligands in monocyte subpopulations by flow cytometry and expression of Notch - pathway related genes and immune response. In addition, plasma was used to assess levels of cytokines, CD14s and CD163s. Furthermore, we evaluated the cellular function dependent on the activation of the Notch pathway during the infection of peripheral blood mononuclear cells of healthy subjects with Mtb H37Rv in vitro. We observed that patients with active TB had increased DLL4 expression in intermediate and nonclassic monocytes and decreased expression of Notch 2 in CD8+ T cells. In vitro, we observed in the cultures of PBMCs, increased expression of DLL4 in intermediate monocytes and Notch 2 in CD4+ T cells. The expression of the DLL4 linker in intermediate monocytes and the expression of Notch 1 in CD4+ T cells in patients with active TB correlated positively with the degree of lung injury. In addition, patients with moderate and advanced lung injury have higher Notch 1 expression in CD4+ T cells when compared to patients with a minimal degree of lung injury. Patients with active TB showed a significant increase in plasma levels of IL-6, IP-10, CD14s and CD163s, and decreased levels of IFN-?, IL-17A, IL-4, IL-2, IL-1? and RANTES. The plasma levels of IFN-?, TNF-?, IL-17A, IL-4, IL-2, IL-12, IL-1?, RANTES and IL-10 correlated positively with the highest degree of lung injury. In addition, we demonstrated that levels of IFN-?, IL-17A, IL-1?, IL-4 and IL-2 are related to higher Notch 1 receptor expression in CD4+ T cells, whereas plasma levels of IP-10,CD163s and procalcitonin correlate with increased Notch 1 expression in CD8+ T cells. We have shown a greater trend in HES1 expression in patients with active TB and in vitro infected cells, indicating that the Notch pathway is being activated during Mtb infection. Interestingly, in vitro cultures of PBMCs treated with the Notch pharmacological inhibitor (GSI), reduced IL-17A, IL-2 and IL-10 production and increased IL-8, while anti-hDLL4 treatment promoted the significant increase in TNF-? levels and monocyte phagocytic activity. In conclusion, the expression of Notch receptors and ligands is altered during TB, especially the DLL4 linker in monocyte subpopulations. In addition, the Notch pathway appears to be important in modulating pro and anti-inflammatory responses. In this work, we suggest that Notch 1 expression in T cells and DLL4 in monocyte subpopulations is associated with TB severity. Thus, detection of these constituents of the Notch pathway in PBMCs of patients with active TB are potential biomarkers to assess disease progression.

abstract: Alzheimer’s Disease (AD) and Frontotemporal Dementia (FTD) are the leading causes of early onset dementia. There are currently no ways to slow down progression, to prevent or cure AD and FTD. Both AD and FTD share a lot of the symptoms and pathology. Initial symptoms such as confusion, memory loss, mood swings and behavioral changes are common in both these dementia subtypes. Neurofibrillary tau tangles and intraneuronal aggregates of TAR DNA Binding Protein 43 (TDP-43) are also observed in both AD and FTD. Hence, FTD cases are often misdiagnosed as AD due to a lack of accurate diagnostics. Prior to the formation of tau tangles and TDP-43 aggregates, tau and TDP-43 exist as intermediate protein variants which correlate with cognitive decline and progression of these neurodegenerative diseases. Effective diagnostic and therapeutic agents would selectively recognize these toxic, disease-specific variants. Antibodies or antibody fragments such as single chain antibody variable domain fragments (scFvs), with their diverse binding capabilities, can aid in developing reagents that can selectively bind these protein variants. A combination of phage display library and Atomic Force Microscopy (AFM)-based panning was employed to identify antibody fragments against immunoprecipitated tau and immunoprecipitated TDP-43 from human postmortem AD and FTD brain tissue respectively. Five anti-TDP scFvs and five anti-tau scFvs were selected for characterization by Enzyme Linked Immunosorbent Assays (ELISAs) and Immunohistochemistry (IHC). The panel of scFvs, together, were able to identify distinct protein variants present in AD but not in FTD, and vice versa. Generating protein variant profiles for individuals, using the panel of scFvs, aids in developing targeted diagnostic and therapeutic plans, gearing towards personalized medicine. / Dissertation/Thesis / Doctoral Dissertation Neuroscience 2018

An estimated 1,735,350 new cancer diagnosis and 609,640 cancer related deaths are predicted to occur in the United States in 2018. To improve patient prognosis, biomarkers are needed to identify cancer in early stages. When diagnosed at an early stage, cancer is more likely to respond to treatments and patients have a higher survival rate. Consequently, there is an ever-present need to identify biomarkers that can aid in the detection of cancer. Additionally, there is a paradigm shift in the field of cancer treatment towards immunotherapy. Traditional cancer treatments include chemotherapy, radiation, and hormone therapy and are not cancer-specific, which leads to bystander effects on the patient<&trade>s normal organs that often harm the patient and create unnecessary hardship. To alleviate this, immunotherapy utilizes a patient<&trade>s own immune cells to attack and destroy cancer cells via cancer-specific biomarkers. These biomarkers are ideally on the surface of cancer cells and absent from the patient<&trade>s normal cells to avoid healthy tissue destruction. With this new therapy, there is a recent push to find surface antigens for immunotherapy techniques.This dissertation describes the characterization of HPRT as a diagnostic and therapeutic biomarker for the detection and possible treatment of hematological and solid malignancies. We describe the general upregulation of HPRT upon malignancy and show that this elevation in protein expression is independent of stage, which indicates that it would be useful as an early stage diagnostic companion tool. We have preliminarily linked the elevation in HPRT to a mutation in one of its prime transcription factors, p53. Specific mutation in p53 called Gain of Function mutations have shown to influence salvage pathway enzyme expression, and we have shown that mutations in p53 are relevant to the elevated levels of HPRT within several cancer types. In addition, we also found that HPRT associates significantly with the membrane of several cancer cell lines as well as patient samples. We found that HPRT has insignificant expression on normal cells, which suggests it may be useful as a targetable biomarker for immunotherapy. Throughout our analysis, we also determined that HPRT might have a role in immune regulation as an elevation of the protein correlates to the decrease of several pro-inflammatory genes involved in immune activation. The knowledge gained from the data presented in this dissertation have opened up new functions for HPRT outside of simple nucleotide production and have confirmed that HPRT has a unique role in cancer that has not been previously reported.

Obesity, elevated blood pressure and dyslipidemia are highly prevalent in Hispanic children. Compared to their non-Hispanic White peers, Hispanic children experience higher prevalence of obesity and hypertension. The Hispanic population in Tennessee has been growing, with about a tenth of newborn babies being Hispanic. This study aimed to: 1. Examine the influence of sociodemographic factors on Hispanic children’s cardiometabolic risk; 2. Assess the relationship between food group intake and cardiometabolic risk in Hispanic children; and 3. Evaluate the efficacy of non-traditional biomarkers for detecting cardiometabolic risk in Hispanic children. Data for the study came from a larger cross-sectional pilot study of metabolic syndrome in Hispanic children attending a community health center in Johnson City, TN. Descriptive and multiple logistic regression analyses were used. The prevalence of overweight and elevated blood pressure were 40.7% and 31.0% respectively. Children of obese mothers were more likely than children of mothers with normal body mass index to engage in less than three days of at least 60 minutes of vigorous physical activity (PA) per week (OR: 6.47: 95% CI: 1.61-26.0). Children whose mothers did not engage in moderate PA were more likely to have elevated blood pressure (OR: 2.50, 95%CI: 1.02-4.53); and to engage in less than three days of at least 60 minutes of vigorous PA per week (OR: 2.92, 95% CI: 1.18-7.24), than children whose mothers engaged in moderate PA. Children generally exceeded fruit and legume intake recommendations, but did not meet vegetable, wholegrain, dairy and fiber recommendations. Higher legume (OR: 0.052, 95% CI: 0.04-0.64), dairy (OR: 0.61, 95% CI: 0.37-0.99) and fiber intake (OR: 0.88, 95% CI: 0.81-0.96) were protective against elevated blood pressure, but only fruit intake was protective against overweight (OR: 0.93, 95% CI: 0.87-0.99). Leptin, C-peptide and TNF-α showed significant positive correlations with cardiometabolic risk factors. The optimal cut-offs for detecting three or more cardiometabolic risk factors were: leptin, 5.95 ng/ml, C-peptide, 0.73 ng/; and TNF-alpha, 4.28 pg/ml. Helping mothers to achieve and maintain a healthy BMI and promoting children’s consumption of more vegetables, fruits, dairy and fiber could help reduce cardiometabolic risk in Hispanic children.

abstract: Autism spectrum disorder (ASD) is a developmental neuropsychiatric condition with early childhood onset, thus most research has focused on characterizing brain function in young individuals. Little is understood about brain function differences in middle age and older adults with ASD, despite evidence of persistent and worsening cognitive symptoms. Functional Magnetic Resonance Imaging (MRI) in younger persons with ASD demonstrate that large-scale brain networks containing the prefrontal cortex are affected. A novel, threshold-selection-free graph theory metric is proposed as a more robust and sensitive method for tracking brain aging in ASD and is compared against five well-accepted graph theoretical analysis methods in older men with ASD and matched neurotypical (NT) participants. Participants were 27 men with ASD (52 +/- 8.4 years) and 21 NT men (49.7 +/- 6.5 years). Resting-state functional MRI (rs-fMRI) scans were collected for six minutes (repetition time=3s) with eyes closed. Data was preprocessed in SPM12, and Data Processing Assistant for Resting-State fMRI (DPARSF) was used to extract 116 regions-of-interest defined by the automated anatomical labeling (AAL) atlas. AAL regions were separated into six large-scale brain networks. This proposed metric is the slope of a monotonically decreasing convergence function (Integrated Persistent Feature, IPF; Slope of the IPF, SIP). Results were analyzed in SPSS using ANCOVA, with IQ as a covariate. A reduced SIP was in older men with ASD, compared to NT men, in the Default Mode Network [F(1,47)=6.48; p=0.02; 2=0.13] and Executive Network [F(1,47)=4.40; p=0.04; 2=0.09], a trend in the Fronto-Parietal Network [F(1,47)=3.36; p=0.07; 2=0.07]. There were no differences in the non-prefrontal networks (Sensory motor network, auditory network, and medial visual network). The only other graph theory metric to reach significance was network diameter in the Default Mode Network [F(1,47)=4.31; p=0.04; 2=0.09]; however, the effect size for the SIP was stronger. Modularity, Betti number, characteristic path length, and eigenvalue centrality were all non-significant. These results provide empirical evidence of decreased functional network integration in pre-frontal networks of older adults with ASD and propose a useful biomarker for tracking prognosis of aging adults with ASD to enable more informed treatment, support, and care methods for this growing population. / Dissertation/Thesis / Masters Thesis Biomedical Engineering 2019

Mass spectrometry has emerged as having a vital role in various applications to biochemical fields. In this thesis, we have utilized a variety of mass spectrometry techniques for both bacteriophage proteomics and colostrum and milk lipidomics studies. Our first study was the proteome characterization of Great Salt Lake bacteriophage NS01 with SDS-PAGE GEL to separate the viral proteins and high performance liquid chromatography (HPLC) coupled with an LTQ Orbitrap to identify the proteins after in-gel digestion. In this project, we have successfully identified 11 proteins with high confidence, p-values < 0.01, including coat protein gp88 with a coverage of 91% and tail protein gp86 with a coverage of 40.96%, which facilitated the classification of NS01 as a T7-like phage. Our second study was the discovery of colostrum and milk biomarkers that can be used to predict the likelihood of development of production-related metabolic diseases (PRMDs) in dairy cows through a lipidomics approach. In this study, an electrospray ionization, time-of-flight mass spectrometer was applied to lipid profiling, quantification and significant biomolecule selection. A Q-Star quadrupole, orthogonal time-of-flight mass spectrometer and an Agilent 6530 accurate-mass quadrupole/time-of flight mass spectrometer were both used for lipid biomarker fragmentation and identification. According to linear discriminative statistical modeling, three panels of biomarkers were defined. A combination of 2 milk lipid predictors, including DG18:0/18:0 and TG 18:0/18:0/18:1, provided PRMD predictions with 75.0% sensitivity at 90.0% specificity. A combination of 3 colostrum lipid predictors, including TG16:0/18:1/18:3, DG16:0/16:0 and C40H60NO, provided PRMD prediction with 90.0% sensitivity at 86.4% specificity. Furthermore, a combination of 7 colostrum and milk biomarkers, including calculated differences between 'shared' markers found to be significantly different in both colostrum and milk, provided a predictive sensitivity of 87.5% at a specificity of 100%. Thus, three panels of lipid biomarkers have been discovered in 1-4 day postparturient dairy cow colostrum and milk that can be used to predict resistance or susceptibility prior to onset of clinically apparent PRMDs. These novel lipids could be used as important diagnostic predictors in the future. Therefore, mass spectrometry based proteomics and lipidomics approaches have been efficient tools in the biochemical research described in this thesis.