A meningite meningocócica permanece como importante causa de morbidade e mortalidade em todo o mundo. Extratos purificados de LOS de Neisseria meningitidis foram utilizados em um ensaio de ELISA a fim de detectar a especificidade dos anticorpos anti-LOS produzidos por 41 pacientes com doença meningocócica. Durante o período de convalescença, 100% dos pacientes apresentaram aumento da concentração sérica de IgG anti-LOS (L1, L2, L3,7, L6, L8 e L10) em no mínimo três vezes a concentração verificada nos soros coletados durante a fase aguda. O maior aumento foi de oito vezes para IgG anti-L3,7 adicionada de resíduo de ácido siálico. Portadores de Neisseria meningitidis e Neisseria lactâmica na nasofaringe não produziram anticorpos anti-LOS. Através de um ensaio ELISA de Inibição, foi possível verificar a especificidade dos anticorpos anti-LOS, exceto para os anticorpos IgG anti-L10, que apresentaram reação cruzada com outros tipos antigênicos de LOS como L2, L3,7 e L6, revelando-se um importante candidato a antígeno vacinal. / Meningococcal meningitis remains as an important cause of morbidity and mortality all over the world. Purified LOS extracts were used in an ELISA assay to verify the specificity of the antibodies produced due to meningococcal disease. All 41 convalescent sera collected from patients had at lowest a three-folder increase of anti-LOS IgG concentrations when compared with acute sera. A higher increase of eight fold was seen to anti-L3,7 IgG specific antibodies. Safe carries of Neisseria meningitidis and Neisseria lactamica had no detectable specific anti-LOS antibodies. In an Inhibition ELISA assay, except for anti-L10 IgG, antibodies against L1, L2, L3,7, L6 and L8 immunotypes were specific. Anti-L10 antibodies cross-reacted with L2, L3,7 and L6 epitopes.

No útero gestante dos animais com placentação do tipo hemocorial, ocorre uma migração e acúmulo transitório de linfócitos natural killer (NK) , cuja atuação na gestação não está totalmente elucidada. Estas células NK do ambiente uterino (uNK) apresentam comportamento distinto daquelas encontradas no sangue circulante (cNK), constituindo uma sub-população das células NK com expressão gênica específica ditada pelo ambiente uterino gestante. De fato, se estas células isoladas do útero de camundongos prenhes forem inoculadas em machos da mesma espécie eram capazes de induzir a resposta imunológica com produção de anticorpos que reagem especificamente com as células uNK. No presente trabalho foi utilizado um destes anticorpos monoclonais denominados de \"mouse anti-mouse uterine natural killer cell clone 1 (mam-uNK1)\" obtidos anteriormente em nosso laboratório para avaliar a especificidade deste anticorpo e a localização da molécula antigênica correspondente. Para tanto, foram utilizados cortes histológicos do útero no 9º dia de gestação, dos órgãos linfóides (baço, timo e linfonodo), do cérebro, do fígado e do coração submetidos à reações imunocitoquímicas com o anticorpo mam-uNK1 em nível da microscopia de luz e, pela imunomicroscopia eletrônica nas células uNK do útero gestante e células estriadas cardíacas do miocárdio. Foram obtidos homogenados teciduais dos mesmos órgãos avaliados pela imunocitoquímica para realização do SDS-PAGE e Western-blot com o intuído de identificar as frações protéicas reativas e homologia entre os diversos órgãos. Os padrões de imunomarcação com o mam-uNK1 foram comparadas com o padrão de reatividade da lectina DBA (Dolichos biflorus) tanto nos cortes histológicos quanto nos homogenados submetidos ao Western-blot. Os resultados demonstraram reação positiva distribuída difusamente no citoplasma, com maior intensidade no perímetro das células uNK, e marcação difusa no citoplasma das células deciduais e das células musculares lisas do miométrio. Reações positivas foram encontradas também no citoplasma das células musculares cardíacas, no citoplasma das células reticulares dos órgãos linfóides, nos feixes de nervos do sistema nervoso central e no citoplasma dos hepatócitos. Pela imunomicroscopia eletrônica foram observadas partículas de ouro coloidal em maior número no citoplasma que preenchem os prolongamentos citoplasmáticos tipo microvilosidades e no citoplasma marginal abaixo da membrana plasmática nas células uNK. Nas células musculares cardíacas as marcações mais intensas foram constatadas no citoplasma da extremidade destas células onde as miofibrilas eram menos organizadas e se ancoravam à membrana plasmática. Pelo Western-blot, foram identificadas duas bandas reativas ao mam-uNK1 com peso molecular de 52 e 54 kDa comuns a todos os órgãos analisados. Estes dados demonstram que a molécula reconhecida pelo anticorpo mam-uNK1 tem ampla distribuição em diversos tipos celulares não sendo específica para as células uNK, porém apresentam uma localização peculiar nestas células e nas células musculares cardíacas. Pelo padrão de localização identificado em imunomicroscopia eletrônica, presume-se que estas moléculas estejam associadas com a modulação do citoesqueleto nas diversas atividades que estes componentes estruturais desempenham nas células, sendo particularmente interessante a relação com a motilidade celular. / In the pregnant uterus of animals developing hemochorial type placentation occurs a transient migration and accumulation of natural killer lymphocytes (NK) which activity in the pregnancy has not been fully elucidated. These NK cells from uterine environment (uNK) present a distinct behavior from those found in the peripheral circulating blood (cNK), composing a subset of NK cells with specific gene expression that is regulated by pregnant uterus. Actually, these cells isolated from pregnant mice uteri were inoculated in the male mice of same strains, they induced immune response with production of antibodies reactivity specifically to uNK cells. In the present work it was used one of these mouse anti-mouse uterine natural killer cells clone 1 (mam-uNK1) monoclonal antibody that was obtained previously in our laboratory, in the aim to evaluate the specificity of this antibody and localization of corresponding antigenic molecule. It was used histological sections of uteri on 9º gestational day, lymphoid organs (spleen, thymus and lymph node), brain, liver and heart processed for immunocytochemistry with mam-uNK antibody at light microscopy and immunoelectron microscopy for uNK cells in pregnant uterus and cardiac muscle cells. Tissue homogenates from the same organs that were evaluated by immunocytochemistry were obtained to perform SDS-PAGE and Western-blot primary to identify the proteins fractions reactive with mam-uNK antibody and possible homology among the tissues. The immunolabeling pattern using mam-uNK both, in histological sections and Western-blot were compared with pattern of Dolichos biflorus (DBA) lectin reactions. The results showed diffuse positive reaction distributed in the cytoplasm with higher intensity on perimeter of uNK cells and diffuse labeling in the cytoplasm of decidual cells and, in smooth muscle cells of miometrium. Positive reaction was also found in the cytoplasm of cardiac muscle cells, reticular cells of lymphoid organs, hepatocytes and in the axon bundles of the brain. By immunelectron microscopy, were observed higher number of gold particles in the cytoplasm of microvillous-like cell processes and in the marginal cytoplasm near the plasma membrane of uNK cells. In the cardiac muscle cells the most conspicuous labeling was seen in the cytoplasm of muscle cells at the end portions, that is, where the myofibrills were less organized and anchoring to plasma membrane. The Western-blot identified two bands with 52 and 54 kDa reactive do mam-uNK constantly found in all organs analyzed. These data show that the molecule that is recognized by mam-uNK1 antibody is widely distributed in several cell types, not specific for mouse uNK cells, but has a very peculiar localization in these cells and in the cardiac muscle cells. To the localization pattern that was identified by immunelectron microscopy it was suggested that, these molecules were associated to the modulation of the cytoskeleton in many activities that these structural component potentially could carry out in the cells, being particularly attractive those related to cell motility.

O gene humano KIAA0090 mapeia uma região cromossômica (1p36.13) com freqüentes aberrações em cânceres humanos e é superexpresso em muitos tipos de tumores. É um gene altamente complexo cujas seqüências de cDNA oriundas de bases de dados públicas apóiam a existência de mais de 20 transcritos alternativos. Sua RefSeq prediz a codificação de uma proteína altamente conservada com 993aa, cujo ortólogo em S. cerevisae (ECM1) foi proposto recentemente atuar no enovelamento de proteínas transmembrana no retículo endoplasmático (RE). O objetivo deste trabalho foi adquirir conhecimento sobre a localização e função da proteína KIAA0090, em células e tecidos normais e tumorais, bem como em células expostas a estresse. Geramos anticorpos policlonais (anti-K2) contra a metade C-terminal da proteína e comparamos seu padrão ao tratamento obtido com o anticorpo (anti-K1), previamente gerado contra a metade N-terminal. A proteína endógena foi localizada primariamente no Golgi e na mitocôndria, dependendo se o anticorpo utilizado foi contra a região N- ou C-terminal, respectivamente. Observamos também, embora menos notável, uma marcação sobreposta com a rede do RE e na margem celular, e variáveis graus de marcação dentro do núcleo e associada a pequenas partículas citoplasmáticas. A análise imunohistoquímica forneceu evidências que a KIAA0090 é ubiquamente epressa. O anti-K2 marcou estruturas semelhantes a Golgi em todo tipo celular, predominando assim naquelas com Golgi mais visíveis, como células secretórias. Observamos para a maioria dos tecidos uma marcação leve a moderada para o anti-K1, mas uma forte marcação foi encontrada em grupos restritos de células, como as células reticulares do timo, epitélio ductal das glândulas da língua e na lâmina basal do epitélio escamoso na zona de transição esôfago-gástrica. Em cortes histológicos de melanoma primário, observamos uma forte marcação para o anti-K1, principalmente em vasos e em células invasoras na margem do tumor, enquanto o anti-K2 mostrou um padrão sugestivo de infiltrado inflamatório e/ou células mesenquimais. Em tecidos de câncer de mama, vimos uma forte marcação nas células de carcinoma ductal em comparação ao epitélio ductal normal para o anti-K2, ao passo que o anti-K1, marcou fortemente vasos e células basais no epitélio de revestimento glandular, tanto no tecido normal como no tumoral. Utilizando uma matriz com amostras teciduais de câncer de mama obtidas de 96 pacientes, observamos uma marcação forte a moderada para o anti-K1 em 84% dos casos, enquanto 16% dos casos não apresentaram marcação. Notamos que os casos positivos para o anti-K1 estavam 100, 85 e 71% entre os casos de grade 1, 2 e 3, respectivamente, sugerindo uma tendência de perda da KIAA0090 associada à progressão do câncer de mama. Foi interessante notar que a brefeldina A e MG132 alteraram os níveis de RNAm da KIAA0090 e levaram à redistribuição da proteína endógena. Outros tratamentos de estresse, incluindo tunicamicina, complexo de rutênio doador de óxido nítrico e etoposídeo, também alteraram o padrão de distribuição da proteína. Este estudo fornece evidências preliminares que corroboram os resultados obtidos de estudos de expressão gênica em larga escala, fortalecendo os indícios de que a KIAA0090 desenvolve um papel na homeostase celular e está envolvida no câncer. / Human KIAA0090 gene maps to a chromosomal region (1p36.13) with frequent aberrations in cancer and is overexpressed in many tumor types. It is a highly complex gene with cDNA sequences in databases supporting the occurrence of more than 20 alternative transcripts. The RefSeq transcript is predicted to encode a highly conserved 993 aa transmembrane protein whose S. cerevisiae ortolog (EMC1) was recently proposed to function on transmembrane protein folding in the endoplasmic reticulum (ER). The aim of this work was to gain insight into the localization and function of KIAA0090 protein, in normal and tumor cells and tissues, as well as in cells exposed to stress treatments. We raised a polyclonal antibody (anti-K2) to the C-terminal half of the protein and compared its pattern of staining with an antibody (anti-K1) previously generated in our laboratory to the N-terminal half. The endogenous protein was primarily localized either to mitochondria or Golgi, depending whether the antibody used was to the N- or C-terminal, respectively. Also, less conspicuous staining overlapped with the ER network and cell margin, and variable degrees of labeling was observed within the nucleus and associated to small cytoplasmic particles. Immunohistochemistry survey provided evidence that the KIAA0090 protein is ubiquitously expressed. Anti-K2 labeled in a Golgi-like pattern in every cell type, predominating in those with more conspicuous Golgi, such as secretory cells. Faint to moderate anti-K1 staining was found in most tissues, but very strong staining was seen in restricted groups of cells, such as thymus reticular cells, ductal epithelium of salivary lingual glands and the basal layer of the squamous epithelium in the esophagus-gastric transition zone. In histological sections of primary melanomas, we observed a strong staining for the anti-K1, mostly in vessels and at the invasive tumor margin, while the anti-K2 showed a staining pattern suggestive of infiltrating inflammatory and mesenchymal cells. In breast tissues, stronger staining was seen in ductal carcinoma cells in comparison to normal ductal epithelium for anti-K2 antibody, whereas anti-K1 strongly marked vessels and basal cells in epithelia lining glandular ducts both in normal and tumor tissues. Using a tissue array of breast cancer samples obtained from 96 patients, we observed strong to moderate staining for anti-K1 in 84% of the samples and lack of staining in 16%, interestingly anti-K1 positive cases were 100, 85 and 71% among cases of grades 1, 2 and 3, respectively, suggesting a tendency of KIAA0090 loss associated with breast cancer progression. A positive correlation was found with estrogen receptor expression and the opposite for HER2. Interestingly, Brefeldin A and MG132 altered KIAA0090 mRNA levels and caused endogenous KIAA0090 protein to redistribute. Other stress treatments, including tunicamycin, a ruthenium complex nitric oxide donor and etoposide, also altered KIAA0090 distribution. This study supports the notion that KIAA0090 play a role in cellular homeostasis and is involved in cancer.

Orientador: Laura Sterian Ward / Dissertação (mestrado) - Universidade Estadual de Campinas. Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-15T07:53:42Z (GMT). No. of bitstreams: 1 Santos_AnaPaulaCarneiroDos_M.pdf: 2998875 bytes, checksum: 9fd6ce397ec8eae4d85db8afcd041e9e (MD5) Previous issue date: 2010 / Resumo: Fragmentos de anticorpos recombinantes têm se tornado ferramentas importantes em diversas áreas, tais como: Biologia Molecular, Farmacêutica e pesquisa Médica. Avanços recentes estão relacionados à aplicação desses anticorpos na oncologia, com estratégias diagnósticas e terapêuticas para diferentes carcinomas. Neste estudo, uma biblioteca de fragmentos de anticorpos monoclonais scFv foi construída utilizando RNA total de sangue periférico de 25 pacientes com Carcinoma Diferenciado da Tireóide. Essa biblioteca scFv foi selecionada utilizando os métodos Bioppaning and Rapid Analysis of Selective Interactive Ligands (BRASIL) e Phage display contra células tumorais de tireóide, com o objetivo de encontrar ligantes específicos a superfície celular tumoral. Os clones selecionados foram identificados por Dot blotting, e a reatividade contra proteínas de tumor, adenoma e bócio foi analisada por Elisa. O clone scFv-C1 apresentou melhor reatividade pelas proteínas tumorais e foi escolhido para a imunoistoquímica. Esta foi realizada com lâmina de Micro-arranjo de tecido (TMA) com duzentos e vinte nove casos de tireóide, sendo 110 Carcinomas, 52 Adenomas Foliculares, 49 Bócios e 18 tecidos normais de tireóide. O anticorpo scFv-C1 reagiu especificamente aos tecidos de câncer, com reatividade ao citoplasma das células tumorais, foi capaz de distinguir o Grupo Câncer do Controle (Bócio, Adenoma e tireóide normal) com significância estatística (p<0,0001) e entre os carcinomas reagiu melhor com os tumores pequenos (TNM 1 e 2) e com pouca agressividade (p=0,050). O fragmento de anticorpo scFv-C1 pode ser um potencial candidato a biomarcador para o diagnóstico do Câncer de tireóide / Abstract: Recombinant antibody fragments have become important tools in several fields, including molecular biology, pharmaceutical and medical research. In this study, a human single-chain variable fragment (scFv) antibody library was constructed using total RNA of leukocyte cells obtained from blood of patients with well differentiated thyroid carcinoma. This scFv antibody library was selected using the Biopanning and Rapid Analysis of Selective Interactive Ligands method (BRASIL) and Phage display technology against tumor thyroid cells, aiming to find specific cell-surface binders. The selected clones were identified by dot blot and ELISA assays and their reactivity analyzed against tumor, goiter and adenoma proteins. One clone (scFv-C1) presented the highest reactivity ratio between cancer and the control group (goiter and adenoma) and was chosen for further analysis. Immunohistochemistry was performed by means of Tissue Microarray with two hundred and twenty-nine thyroid cases (110 carcinomas, 52 follicular adenomas, 49 goiters and 18 normal tissues) including 38 papillary, 42 follicular and 30 variant follicular in the carcinoma group. The scFv-C1 reacted specifically to cancer tissues sections, showed strong reactivity with cytoplasm and was able to distinguish cancer to control groups (goiter, adenoma and normal thyroid) with_statistically significance (p<0,0001). The scFv-C1 fragment antibody described here may be a potential biomarker candidate for diagnostics and prognostics of thyroid cancer / Mestrado / Ciencias Basicas / Mestre em Clinica Medica

O óxido nítrico (NO) é um mensageiro biológico que tem importância vital em muitos processos fisiológicos e apresenta uma multiplicidade de funções de regulação no corpo humano, tais como neurotrasmissão, vasodilatação, participa nas respostas imunes e em vários processos associados com o desenvolvimento dos tumores. Vários estudos fornecem evidências sobre as propriedades tumoricidas do óxido nítrico e doadores de NO que podem ser usados para o tratamento de tumores malignos e são objetos de interesse na atualidade. Baseado nisto o objetivo deste trabalho foi de sintetizar e descrever aspectos estruturais dos compostos [Ru(bpy)2(dcbpy)] (dcbpy = ácido 4,4\'-dicarboxi-2,2\'-bipiridina, bpy = 2,2\'-bipyridina) [Ru(bpy)(dcbpy)2], cis-[RuCl2(dcbpy)2], cis-[Ru(dcbpy)2NO(L)]n+ (L = cloreto), [Ru(TERPY)(dcbpy)Cl] (TERPY = 2,2\': 6\'\', 2\'\' - terpiridina) and [Ru(TERPY)(dcbpy)NO], além de ensaios de citotoxicidade in vitro para alguns dos complexos sintetizados. Ensaios de citotoxicidade com solução aquosa de complexos rutênio-nitrosilo em linhagem de células metastáticas B16-F10 mostrou resultados relativamente baixos. Medidas de viabilidade celular mostrou que estes decrescem cerca de 10 % em relação ao controle. Este resultado foi interpretado como sendo devido a baixa interação entre o complexo e a célula. Bioconjugação de rutênio-nitrosilo com anticorpo policlonal IgG foi obtido por interação convalente e mostrou maior especificidade com um alvo na célula. Cromatografia de exclusão foi utilizada para separar o bioconjugado --IgG, que foi caracterizado por teste Western Blotting. Após a bioconjugação, o --IgG foi submetido a estudos de citotoxicidade com células metastáticas e a viablidade celular avaliada com ensaios MTT. Os resultados exibiram um incrível aumento na citotoxicidade de células B16-F10. Viabilidade celular foi determinada e valores de morte celular de cerca de 90 % obtida para uma das frações de --IgG. Nossos resultados demonstraram que o bioconjugado --IgG pode aumentar a resposta citotóxica e quiçá ser útil em terapia clínica. / Nitric oxide (NO) is a biological messenger that has vital importance in many physiological processes and shows a multitude of regulatory roles in the human body, such as neurotrasmission, vasodilatation, immune responses and also participates in various processes associated with cancer development. Several studies provide evidences of the tumoricidal properties of NO donors that can be used for the treatment of malignant tumors and nowadays are objects of interest. Based on this the aim of this work was synthesize compounds that in a controlled manner can deliver NO in a biological process. The synthesis, structural aspects, and in vitro cytotoxic properties of [Ru(bpy)2(dcbpy)] (dcbpy = 2,2\'-bipyridine-4,4\'-dicarboxylic acid), 2\'-bipyridine; bpy = 2,2\'-bipyridine) [Ru(bpy)(dcbpy)2], cis-[RuCl2(dcbpy)2], cis-[Ru(dcbpy)2NO(L)]n+ (L = chloride), [Ru(TERPY)(dcbpy)Cl] (TERPY = 2,2\': 6\'\', 2\'\' - terpiridine) and [Ru(TERPY)(dcbpy)NO] are described. Citotoxicity assays with aqueous nitrosyl ruthenium complex in metastatic B16-F10 cells displayed very little effect. Cell viability measurement showed decrease around 10 % in comparison to the control. It was associated due to the low interaction between nitrosyl ruthenium specie and the cell. Bioconjugation of nitrosyl ruthenium specie with polyclonal antibody IgG was achieved by covalent interaction and showed more specific interaction between bioconjugated and target cell. Exclusion chromatography was used to isolate --IgG conjugated, which was characterized by Western Blotting test. Following bioconjugation, the --IgG was submitted to cytotoxic studies with metastatic cells and the viability evaluated by MTT assay. The results displayed incredible increase of citotoxicity for B16F10 cells. Cell viability was achieved to decrease until to 90 % in comparison to the control when one fraction of --IgG was used. Taken together, the present findings demonstrate that the --IgG complex may elicit citotoxicity responses that may find useful applications in clinical therapy.

Introdução: Anemias hemolíticas induzidas por fármacos (AHIF) são caracterizadas por uma anemia hemolítica imune após exposição a um fármaco. Testes sorológicos têm o potencial de confirmar a presença de anticorpo contra fármacos, mas a realização destes testes ainda é um desafio. Os anticorpos IgM e IgG envolvidos na AHIF são principalmente de dois tipos: fármaco-dependentes e fámaco-independentes. Os anticorpos fármaco-independentes reagem com os eritrócitos \"in vitro\" sem a presença do fármaco, e os resultados imunohematológicos são idênticos aos encontrados nas anemias hemolíticas autoimunes idiopáticas. Anticorpos fármaco-dependentes resultam em teste da antiglobulina direto (TAD) positivo e eluato negativo, os anticorpos só reagem \"in vitro\" com os eritrócitos na presença do fármaco. Indivíduos saudáveis podem desenvolver anticorpos contra fármacos, mesmo na ausência de anemia hemolítica. Os indivíduos podem ser sensibilizados durante exposição prévia a fármacos, exposição a antibióticos usados em ração animal, tanques de piscicultura, berçários de criação de suínos ou tratamento de mastite em bovinos. Estes indivíduos apresentam um maior risco de desenvolvimento de AHIF grave na ocasião de uma segunda exposição ao fármaco. Objetivos: Padronizar testes imunohematológicos para a detecção de anticorpos dirigidos contra fármaco-dependentes. Materiais e métodos: Amostras de 162 doadores de sangue foram submetidas a pesquisa de anticorpos fármaco-dependentes anti-cefalexina, anti-rifampicina e anti-diclofenaco de sódio. Amostra de um doador de plaquetas colhidas por aférese com TAD positivo foi investigada para detecção de anticorpos fármaco-dependentes anti-valsartana. Amostras de 8 pacientes com suspeita diagnóstica de AHIF foram investigadas para a presença de anticorpos contra os fármacos que foram prescritos ao paciente no período de duas semanas prévias ou até o momento em que a hemólise aguda foi constatada. Anticorpos fármaco-dependentes que reagem na presença do fármaco ligado covalentemente à membrana da hemácia, ou na presença do fármaco em solução, foram investigados em doadores de sangue (técnicas em gel) e em pacientes (técnicas em tubo e em gel). Resultados: Os testes laboratoriais detectaram a presença de anticorpo anti-valsartana no eluato de um doador de plaquetas colhidas por aférese com TAD positivo e a presença de anticorpo anti-ceftazidima no soro de um paciente com suspeita clínica de AHIF. A investigação de anticorpo anti-cefalexina e anti-rifampicina foi negativa em amostras de doadores de sangue. O teste laboratorial para investigação de anticorpo anti-diclofenaco de sódio não foi finalizado devido a presença de hemólise em hemácias sensibilizadas com o fármaco e após a adição do fármaco na solução de hemácias. Conclusão: A detecção de anticorpo anti-valsartana em um doador de plaquetas colhidas por aférese evidenciou a presença de anticorpo anti-fármaco na ausência de hemólise. A detecção de anticorpo anti-ceftazidima em amostra de um paciente com anemia hemolítica confirmou a suspeita clínica de AHIF. Reconhecer os sinais clínicos da AHIF precocemente e a disponibilidade de testes sorológicos é essencial para confirmação diagnóstica, orientação terapêutica e prevenção de uma hemólise potencialmente fatal. / Introduction: Drug-induced immune hemolytic anemia (DIHA) is characterized by immune hemolytic anemia following exposure to a drug. Serological testing has the potential to confirm the presence of anti-drug antibodies, but the testing is still a challenge. The IgM and IgG antibodies involved in DIHA comprise mainly two types: drug-dependent and drug-independent. Drug-independent antibodies react with erythrocytes in vitro without the presence of the drug, and the immunohematologic results are identical to those found in idiopathic autoimmune hemolytic anemias. Drugdependent antibodies induce positive direct antiglobulin tests (DAT) and negative eluates, and in vitro antibody reactions with erythrocytes are only detected in presence of the drug. Healthy individuals can develop antibodies against drugs even in the absence of hemolytic anemia. Individuals may be sensitized during previous exposure to drugs, exposure to antibiotics used in animal feed, fish culture ponds, swine nurseries or mastitis treatment in bovines. These individuals present higher risk of developing severe DIHA on the second exposition. Aims: To standardize immunohematological tests for detection of anti-drug dependent antibodies. Materials and methods: Samples from 162 blood donors were tested for anti-cephalexin, anti-rifampicin and antidiclofenac antibodies. Sample from one platelet apheresis donor with positive DAT was investigated for anti-valsartan drug-dependent antibody. Samples from 8 patients with suspected DIHA were investigated for the presence of antibodies directed against the drugs that were prescribed to the patient in the period of two weeks prior to or until the time when acute hemolysis was detected. Drug-dependent antibodies that react in presence of the drug covalently attached to the erythrocyte membrane, or in presence of the drug in solution were investigated in samples from blood donors (gel techniques) and from patients (tube and gel techniques). Results: Laboratory tests detected antivalsartan antibody in the eluate of an platelet apheresis donor with positive TAD and anti-ceftazidime antibody in the serum of a patient with clinical suspicion of DIHA. Investigation of anti-cephalexin and anti-rifampicin antibody was negative in blood donor samples. The laboratory test for anti-diclofenac antibody was not possible due to the presence of hemolysis in erythrocytes sensitized with the drug and when the drug in solution was added to the erythrocyte. Conclusion: The detection of anti-valsartan antibody in an platelet apheresis donor revealed the presence of an anti-drug antibody in the absence of hemolysis. Detection of anti-ceftazidime antibody in a patient with hemolytic anemia confirmed the clinical suspicion of DIHA. It is essential to recognizing early clinical signs of DIHA and have serological tests available for diagnostic confirmation, therapeutic guidance and prevention of potentially fatal hemolysis.

Human fungal infections among severely immunocompromised individuals have increased dramatically over the last 30 years and that coincidence with an expanding patient numbers of bone marrow and solid organ transplantation and those receiving aggressive cytotoxic chemotherapy for neoplastic diseases or immunosuppressive drugs. In recent years, many of opportunistic fungi have emerged as serious human pathogens and causing life-threatening infections of humans such as Fusarium species. Due to lack of a highly accurate diagnostic test for tracking the pathogenic Fusarium species, fusariosis is frequently misdiagnosed as aspergillosis. Delays in identification and differentiation of Fusarium spp. from other causative agents of hyalohyphomycetes associated with high morbidity and mortality rate among immunocompromised patients. This research aimed to develop a highly specific monoclonal antibody (mAb) using hybridoma technology to produce a highly genus-specific murine mAb ED7 that could be used for tracking and early detecting circulating Fusarium species antigens from other opportunistic pathogens. At present, a very little is known about the pathogenicity and interaction of human pathogenic F. solani and cells of the innate immune system like alveolar macrophages (AMØ), the residential innate immune cells of alveoli. For this reason, F. solani was genetically transformed with GFP gene and a model of immunoassay was developed to investigate the interactions of F. solani with AMØ that would allow studying the fungal pathogenicity, visualising and quantification of the pathogen during the process of macrophage phagocytosis. In addition, this model can be used to evaluate the effect of a mAb on fungal uptake by AMØ. Habitates providing direct human exposure to infectious propargules are largely unknown, but there is growing evidence that plumbing systems are sources of human pathogenic strains in the F. solani and F. oxysporum species complexes, the most common groups infecting humans. Using mAb ED7 specific to the Fusarium species, this work demonstrates how the mAb can be used as a powerful immunodiagnostic tool for accurately tracking the Fusarium species antigens in sink drain biofilms and water system samples containing mixed populations of human opportunistic filamentous and yeasts pathogenic fungi across a University campus and a tertiary care hospital. Specificity of the ELISA was confirmed by sequencing of the internally transcribed spacer 1 (ITS1)-5.8S-ITS2 rRNA-encoding regions of culturable yeasts and moulds that were recovered using mycological culture, while translation elongation factor (TEF)-1 analysis of Fusarium isolates included FSSC 1-a, FOSC 33 and FDSC ET-gr, the most common clinical pathotypes in each group. The mAb ED7 is, therefore, suitable to be carried forward for use in diagnostic assays, such as the lateral flow device.

Master of Science / Department of Biology / Stephen K. Chapes / Immunoglobulins are receptors expressed on the outside of a B cell that can specifically bind pathogens and toxic substances within a host. These receptors are heterodimers of two chains: heavy and light, which are encoded at separate loci. Enzymatic splicing of gene segments at heavy and light chain loci within the genomic DNA in every B cell results in a highly diversified and specific repertoire of immunoglobulins in a single host. Spaceflight is known to affect reduce splenic B cell populations and B cell progenitors within the bone marrow, potentially restricting the diversity of the immunoglobulin repertoire (Ig-Rep). The objective of this thesis project was to characterize the impact of spaceflight on the kappa light-chain Ig-Rep of the C57BL/6 mouse. High-throughput sequencing (HTS) technologies have enabled the rapid characterization of Ig-Reps, however, standard Ig-Rep workflows often rely the amplification of immunoglobulin sequences to ensure the capture immunoglobulin sequences from rare B cell clones. Additionally, the Ig-Rep is often assessed in sorted B cell populations. Opportunities for spaceflight experiments are limited and costly, and the exclusive amplification of immunoglobulin sequences prior to HTS results in a dataset that cannot be mined for additional information. Furthermore, due to the difficulties of tissue collection in spaceflight, HTS of sorted B cell populations is not feasible. We optimized a protocol in which the Ig-Rep was assessed from unamplified whole tissue immunoglobulin transcripts. The Ig-Rep was characterized by gene segment usage, gene segment combinations and the region in which gene segments are joined. HTS datasets of ground control animals and animals flown aboard the International Space Station were compared to explore the impact of spaceflight on the unimmunized murine Ig-Rep.

Cette thèse étudie trois sujets relevant de la biologie structurale, de lagénétique et de l'immunologie.Premièrement, nous développons de nouveaux prédicteurs de l'affinité deliaison de complexes protéiques, produisant des résultats de niveau ``état del'art''. Nous calculons d'abord 12 variables modélisant diverses propriétésstructurales des complexes. Nous générons et évaluons des estimateursutilisant des sous ensembles de ces variables, de façon à identifier les plusperformants. Le logiciel associé est distribué dans la Structural BioinformaticsLibrary.Deuxièmement, nous proposons de nouvelles analyses de complexes Ig-Ag.D'une part nous concevons un classificateur distinguant les types de ligand desIg. D'autre part, nous montrons que le modèle précédent prédit fidèlementl'affinité de complexes Ig-Ag. Enfin, nous quantifions la contribution des CDR3de la chaine lourde à l'affinité de liaison, et montrons qu'il contribuesignificativement plus que les autres CDR.Enfin, nous nous intéressons à la modélisation de la diversité des répertoiresde chaîne lourde des Igs, à partir de données de séquençage de CDR3, dans unmodèle de vaccin chez le poisson. Nous analysons les répertoires dans troisconditions: naifs, vaccinés et vaccinés + infectés. Nous comparons lesrépertoires de deux individus en utilisant la « earth-mover distance », laquelleexploite la correspondance entre clonotypes de deux répertoires, révélant ainsides informations inaccessibles aux méthodes basées sur les indices dediversité.Dépôt de thèseDonnées complémentairesPour caractériser la notion de réponse immunitaire publique / privée, nousquantifions le chevauchement des clonotypes exprimés entre individus de lamême ou de différentes conditions / This thesis investigates three topics at the cross-roads of structural biology,genetics and immunology.First, we develop a pipeline to design and select binding affinity predictors forprotein complexes, yielding state-of-the art results. The first step is the designand computation of 12 different variables accounting for geometric andphysico-chemical properties of the complexes. The second step is thegeneration and evaluation of models using subsets of these variables, followedby the selection of the best performing ones. The corresponding software isdistributed within the Structural Bioinformatics Library.Second, we provide an analysis of the interface properties of Ig-Ag complexes.In particular, we design a classifier using two descriptors, which is able todistinguish ligand types. We also apply the previous binding affinity predictionmodel to Ig-Ag complexes and obtain accurate predictions. We then develop aquantitative model for the contribution of VH CDR3 to the binding affinity andinteraction specificity, and show that it contributes significantly more thanother CDRs.Third, we model the diversity of VH CDR3 repertoires from Ig RNA sequencingdata in a fish vaccination model. We analyze repertoires from three conditions:naive, vaccinated and vaccinated + infected fish. Comparison of the repertoiresof two individuals uses the earth-mover distance (EMD). By exploiting amapping between the clonotypes of the repertoires, we show that EMD revealsinformation beyond classical methods based on diversity indexes. Tocharacterize the notion of public / private immune response, we quantify theoverlap of clonotypes between individuals of the same or different conditions

L'anticorps recombinant anti-CD4 13B8.2 a démontré des capacités de lyse dépendante du complément (CDC) et d'inhibition de la prolifération cellulaire dans le cadre du traitement des tumeurs hématopoïétiques CD4+. Bien qu'il ait été démontré que son action antiproliférative passe par une modulation du facteur de transcription NF-(kappa)B, les mécanismes précis y conduisant restent encore inexpliqués. Au sein du laboratoire, de précédentes études ont démontré que l'anticorps anti-CD4 13B8.2 induit une réorganisation et une modulation des protéines dans les rafts, en y concentrant le CD4 et en y excluant les protéines ZAP70, SLP76, PLC(nu)1 et Vav1. Nous avons tenté d'expliquer les mécanismes qui participent à la modulation des protéines au sein des microdomaines membranaires lipidiques, et nous proposons que la voie de signalisation Carma1 soit impliquée dans les effets observés sur le facteur de transcription NF-(kappa)B. Cette étude démontre que les effets biologiques de l'anticorps recombinant 13B8.2 passent par une modulation de la voie Carma1, Bcl10, MALT1. L'anticorps 13B8.2 induit une réorganisation de ces protéines en dehors des microdomaines membranaires lipidiques avec une dissociation du complexe qui ne peut plus transmettre la signalisation conduisant à l'activation de NF-(kappa)B. Nous avons également mis en évidence que les réorganisations protéiques au niveau de la membrane, induites par l'anticorps anti-CD4 13B8.2 s'accompagnent d'une modulation des espèces lipidiques des microdomaines. Ainsi, nous observons une augmentation du niveau des acides gras de type C18 :0, et une augmentation de l'activité d'une sphingomyelinase acide qui conduit à une augmentation du taux de céramide. Parallèlement l'augmentation de céramide, induite par une sphingomyelinase bactérienne induit la réorganisation de ZAP70 hors des microdomaines, de façon comparable à l'anticorps 13B8.2. Cette meilleure connaissance des mécanismes de signalisation de l'anticorps anti-CD4 13B8.2, permettra de dégager de nouvelles approches thérapeutiques en vue de la modulation de la prolifération des cellules T et de leur sensibilisation à la chimiothérapie. Ce travail ouvre la voie à des possibilités de thérapies ciblant les microdomaines lipidiques. / The recombinant anti-CD4 antibody 13B8.2 demonstrated capabilities complement dependent lysis (CDC) and inhibition of cell proliferation in the treatment of hematopoietic tumors CD4 +. Although it has been demonstrated that its antiproliferative activity through modulation of transcription factor NF-kB, the precise mechanisms leading to them remain unexplained. Within the laboratory, previous studies have shown that anti-CD4 13B8.2 induced a reorganization and modulation of proteins in rafts by concentrating CD4 and by excluding proteins ZAP70, SLP76, Vav1 and PLC(nu)1 . We tried to explain the mechanisms involved in the modulation of proteins within lipid microdomains, and we propose that the signaling pathway is involved in Carma1 observed effects on the transcription factor NF-kB. This study demonstrates that the biological effects of recombinant antibody 13B8.2 pass through a modulation of the channel Carma1, Bcl10, MALT1. 13B8.2 antibody induces a reorganization of these proteins outside the lipid membrane microdomains with a dissociation of the complex that can no longer transmit signals leading to activation of NF-kB. We also demonstrated that the protein reorganization at the membrane induced by anti-CD4 13B8.2 accompanied by modulation of lipid microdomains species. Thus, we see an increased level of fatty acids like C18: 0, and increased activity of acid sphingomyelinase leads to an increased rate of ceramide. Parallel increase of ceramide, induced by bacterial sphingomyelinase induced reorganization of ZAP70 outside microdomains similarly to the antibody 13B8.2. A better understanding of signaling mechanisms of the anti-CD4 13B8.2, will identify new therapeutic approaches for modulating the proliferation of T cells and their sensitization to chemotherapy. This work paves the way for potential therapies targeted to lipid microdomains.