O Streptococcus pneumoniae (pneumococo) constitui um dos mais importantes patógenos bacterianos do trato respiratório, podendo causar infecções invasivas e não invasivas, levando a altas taxas de morbimortalidade, particularmente em crianças menores de cinco anos de idade. A bactéria ganha acesso ao hospedeiro através da colonização da nasofaringe, que representa um importante reservatório para a transmissão deste patógeno na comunidade, contribuindo para a disseminação horizontal de pneumococo entre os indivíduos de uma população. As doenças respiratórias causadas por pneumococo constituem em uma das prioridades atuais em Saúde Pública, recebendo atenção destacada das organizações internacionais da área da saúde, como a Organização Mundial da Saúde. No presente trabalho procura-se conhecer e avaliar a ocorrência da pneumonia adquirida na comunidade (PAC) antes e após a implantação no Calendário Vacinal da Vacina Pneumocócica-10 Valente Conjugada em 2010, na área de abrangência da Superintendência Regional de Saúde (SRS) de Alfenas/MG. Foi realizado um estudo ecológico com componente temporal que incluiu registros de crianças menores que um ano de idade, vacinadas e não vacinadas com a vacina antipneumocócica 10-valente conjugada, no período pré e pós inclusão da vacina no PNI nos municípios da Superintendência Regional de Saúde (SRS) de Alfenas/MG, sendo a vacinação o fator de exposição e a ocorrência de PAC o desfecho, utilizando dados anuais secundários por município para cálculo da cobertura vacinal e das taxas de morbidade por pneumonia em menores de um ano no período de 2007 a 2013. Considerando se os 26 municípios da SRS de Alfenas, houve redução significativa do número de casos de PAC em crianças abaixo de um ano de idade, cuja Razão de Prevalência foi de 0,81 (IC95%: 0,74 0,89; p<0,05). Mesmo com um tempo reduzido de uso, a vacina pneumocócica conjugada 10 valente apresentou um impacto relevante na redução de PAC em crianças, ajustada por cobertura vacinal no período pós vacinação (2011-2013), sendo estatisticamente significativa na maioria dos municípios, o que sugere a efetividade da vacina PCV-10 na prevenção de casos da doença em crianças menores de um ano de idade. / The Streptococcus pneumoniae (pneumococcus) is one of the most important bacterial pathogens of the respiratory tract, may cause invasive and non-invasive infections, leading to high morbidity and mortality rates, particularly in children under five years of age. The bacteria gain access to the host through the nasopharyngeal colonization, which is an important reservoir for the transmission of this pathogen in the community, contributing to the horizontal spread among individuals in a population. Respiratory diseases caused by pneumococcus are in one of the current priorities in Public Health, receiving outstanding attention of international organizations in the health field, such as the World Health Organization. In the present study we aimed to understand and evaluate the occurrence of community acquired pneumonia (CAP) before and after implantation in 10- valent pneumococcal conjugate vaccine in 2010, on the coverage area of the Regional Health Service (SRS) of Alfenas / MG. An ecological study with temporal component was conducted which included records of children under one year old, vaccinated and not vaccinated with 10-valent pneumococcal conjugate vaccine, before and after period inclusion of the vaccine in PNI, in the municipalities of SRS of Alfenas / MG, with vaccination the exposure factor and the occurrence of CAP the outcome, using annual data side by municipality to calculate vaccination coverage and pneumonia morbidity in children under one year old, in the period 2007 to 2013. Considering the 26 municipalities of SRS Alfenas, there was a significant reduction in the number of CAP cases in children under one year old. The prevalence ratio was 0.81 (95%CI: 0.74 - 0.89; p<0.05). Even with a short period of use, the 10-valent pneumococcal conjugate vaccine had a significant impact on the reduction of CAP in children, adjusted for immunization coverage in the post vaccination period (2011-2013) and was statistically significant in most municipalities, which suggests the effectiveness of PCV-10 vaccine in preventing cases of the disease in children under one year of age.

Introdução: Atualmente a incidência anual de pneumonia adquirida na comunidade nos países em desenvolvimento é de 150,7 milhões de casos entre crianças menores de 5 anos de idade , dos quais 11 a 20 milhões (7-13%) necessitam de internação hospitalar devido à gravidade. O tratamento geralmente é empírico mas o Streptococcus pneumoniae é o principal agente etiológico bacteriano.É necessário manter monitoramento dos sorotipos e padrão de resistência para melhor orientação terapêutica. Metodologia: Estudo de coorte retrospectivo com inclusão de 107 crianças com diagnóstico clínico e radiológico de pneumonia e com isolamento de Streptococcus pneumoniae em sangue e ou líquido pleural no período de janeiro de 2003 a outubro de 2008. Realizado determinação de concentração inibitória mínima (MIC) para penicilina e antibiograma para outros antimicrobianos. A sensibilidade para penicilina utilizada foi conforme Clinical and Laboratory Standards Institute (CLSI ) de 2008. Realizado sorotipagem de 96 cepas de pneumococos (89,7%) e analisados os dados da população em estudo e da evolução clínica. Resultados:Cerca de 47,5% das internações na enfermaria foram por pneumonia ou broncopneumonia e a média de positividade em cultura para pneumococo (sangue e ou líquido pleural) foi de 2,5%. Houve uma sazonalidade bem definida da pneumonia pneumocócica. Cerca de 70% ocorreram nos meses de junho a outubro. A mediana de idade foi de 23 meses (82,2%<5anos); predomínio do sexo masculino (58,9%);utilização de antibioticoterapia nos dois meses prévios à internação de 23,4%; freqüência em creche no menores de 2 anos de 36,4%; apenas um caso com vacinação heptavalente completa; doença associada em 44,9% sendo a mais freqüente a sibilância( 77,1%); tempo de febre e de sintomas respiratórios antes da admissão foi de 4 dias;necessidade de oxigenoterapia não invasiva em 70,1% com tempo médio de utilização de 4 dias;necessidade de ventilação mecânica em 19,6%, mediana do tempo de internação de 9 dias.Em 62% houve complicações sendo as mais freqüentes: empiema (53%) e efusão pleural não complicada (42%). As crianças com empiema tiveram mais pneumonia necrotizante, abscesso pulmonar, sepse, pneumotórax, necessidade de decorticação e ainda maior mortalidade (todas com p<0,05). As crianças com complicações tiveram mais dias de sintomas respiratórios antes da admissão (3x5dias), mais tempo de febre após o início de antibiótico (1x4,5dias), necessitaram de oxigenoterapia não invasiva(58,5x77,3%) e ventilação mecânica (7,3x27,3%) por tempo maior e permaneceram por mais tempo internados (5x12 dias). Das 107 cepas de pneumococo, 100 (93,5%) foram sensíveis à penicilina e 7 (6,5%) de sensibilidade intermediária. Todas as cepas testadas foram sensíveis para rifampicina e vancomicina e ainda mantiveram boa sensibilidade para clindamicina, cloranfenicol, ceftriaxone, eritromicina e levofloxacina. Cinco cepas foram multiresistentes. Notou-se que a média geométrica das concentrações inibitórias mínimas (GMC) para penicilina foram maiores nas crianças com complicações. Os sorotipos mais freqüentes foram: 14(36,5%), 1(16,7%) , 5(14,6%) e 6B(6,3%). O sorotipo 14 apresentou a maior GMC para penicilina e houve um aumento progressivo no decorrer dos anos de estudo. A cobertura dos sorotipos pela vacina heptavalente seria de 53,1% e esta cobertura menor se deve principalmente ao sorotipo 1 e 5, que corresponde a 31,3% dos casos. A cobertura dos sorotipos associados à resistência seria de 94,2%. A cobertura pela vacina 10-valente seria de 86,5% e com a 13-valente seria de 96,9%. Três casos que evoluíram para óbito (2,8%) tinha mediana de idade de 18 meses, todos do sexo masculino, todos com concentração inibitória mínima para penicilina menor ou igual 1g/mL, todos evoluíram com empiema e sepse. Dois foram do sorotipo 5 e um do sorotipo 14. Conclusões: Aproximadamente 2,5% das crianças internadas com diagnóstico de pneumonia foram diagnosticadas como pneumonia pneumocócica.Verificamos uma sazonalidade bem definida.Houve complicações em 62% dos casos. As mais freqüentes foram : empiema e a efusão pleural não complicada. Evidenciou-se uma GMC para penicilina maior nas crianças com complicações comparadas às crianças com ausência de complicações. Os sorotipos mais freqüentes foram 14,1 ,5 e 6B sendo que os sorotipos 1 e 5 totalizam 31,3%. A cobertura pela vacina heptavalente dos sorotipos isolados seria de 53,1%. A sensibilidade para penicilina dos pneumococos isolados de pneumonia foi de 93,5%. Assim, a opção terapêutica continua sendo a penicilina. / Introduction: Currently, the annual incidence of the acquired pneumonia in the developing country communities are around 150.7 million cases, among childrens under 5 years of age, and 11 to 20 million (7-13%) of those require hospitalization due to their gravity. In general, the treatments used to be empirical, however, it is important to be noted that Streptococcus pneumoniae is far the major bacterial etiologic agent. It is necessary to keep monitoring the serotypes and the pattern of resistance in order to improve the therapy guidance. Methodology: Retrospective cohort study with inclusion of the 107 childrens with clinical and radiological diagnosis of the pneumonia, and the isolation of Streptococcus pneumoniae in the blood and/or pleural fluid during the period of January 2003 to October 2008. It was performed determination of the minimum inhibitory concentration (MIC) related to the penicillin and other antibiotics. The sensitivity analysis to the penicillin was based on Clinical and Laboratory Standards Institute (CLSI), 2008, recommendations. They were performed serotyping in 96 pneumococcal strains (89.7%) and they were analyzed datas referred to the considered population and their clinical course. Results: About 47.5% of admissions in the ward were caused by pneumonia or bronchopneumonia, and the average positive occurrences in the pneumococcal (blood and / or pleural) culture were 2.5%. It was noted a clear seasonality phenomena of the pneumococcal pneumonia. About 70% of the cases occurred during months of June to October. The median age was 23 months (82.2%<5 years); with predominance of males (58.9%); in the 23,4% of the cases the antibiotic therapy was used during two months prior to the admission; the daycare frequency of the childs less than 2 years were 36.4%; only one case with complete vaccination heptavalent; associated disease was detected in the 44.9% of the cases and the most frequent was wheezing (77.1%); time of fever and respiratory symptoms before admission were 4 days; the need for noninvasive oxygen therapy occurred in 70.1% being 4 days of the average time of the use; the need for mechanical ventilation occurred in 19.6%; the median period of stay were 9 days. In 62% of the cases there were the most frequent complications: empyema (53%) and non-complicated pleural effusion (42%). The childrens with empyema had more necrotizing pneumonia, lung abscess, sepsis, pneumothorax, need for decortication, and even higher mortality (all with p<0.05). The childrens with complications had more days of respiratory symptoms before admission (3x5days), more time of the fever after initiation with antibiotic (1x4, 5days), they need noninvasive oxygen therapy (58,5 x77, 3%) and mechanical ventilation (7 , 3x27, 3%) for more time and remained hospitalized during longer period(5x12 days). Among 107 pneumococcal strains, 100 (93.5%) were susceptible to penicillin and 7 (6.5%) presented intermediate sensitivity. All strains tested were sensitive to rifampicin and vancomycin, and they maintained good sensitivity to clindamycin, chloramphenicol, ceftriaxone, erythromycin and levofloxacin. Five strains were multi-resistant. It was noted that the geometric mean of minimum inhibitory concentrations (GMC) to penicillin were higher in children with complications. The most frequent serotypes were: 14 (36.5%), 1 (16.7%), 5 (14.6%) and 6B (6.3%). The serotype 14 presented the highest GMC for penicillin and it was verified a progressive increase during the years of the study. The coverage of serotypes by the heptavalent vaccine would be cover 53.1% and this less coverage is represented by serotype 1 and 5, which corresponds to 31.3% of the cases. The coverage of serotypes associated with resistance would be 94.2%. The coverage of the 10-valent vaccine would be 86.5% and for 13-valent would be 96.9%. Three cases that carried to died (2.8%) had median age of 18 months, all they male, all they with minimum inhibitory concentration for penicillin <= 1g/mL, all they progressed to empyema and sepsis. Two of them were serotype 5 and one of them was serotype 14. Conclusions: Approximately 2.5% of children were admitted with diagnosis of pneumonia were diagnosed as pneumococcal pneumonia. It was verified a clear seasonality phenomena. They were observed complications in 62% of the cases. The most frequent were: empyema and non-complicated pleural effusion cases. It was confirmed a higher GMC for penicillin in children with complications compared to the children without complications. The most frequent serotypes were 14, 1, 5 and 6B and the serotypes 1 and 5 accounted 31.3%. The coverage of heptavalent vaccine for the isolated serotypes would be 53.1%. The sensitivity to the penicillin of the isolated pneumococcal was 93.5%. Therefore, the therapy option remains being the penicillin.

A proteína A de superfície de pneumococo (PspA) é indispensável para a virulência da bactéria e foi escolhida para a elaboração de uma nova vacina conjugada contra S. pneumoniae. Para tanto foi desenvolvido um processo industrial de produção e purificação do fragmento recombinante da PspA clado 3 em E. coli. Cultivos descontínuos alimentados foram estabelecidos com glicose ou glicerol em reator de 5L, obtendo-se 62g/L de células secas e 3g/L de PspA3. As células foram lisadas por homogeneizador contínuo de alta pressão com eficiência de 96,7%. A centrifugação foi definida como etapa de clarificação. A sequência cromatográfica troca aniônica seguida de afinidade por Ni+2 rendeu os melhores resultados de pureza (81%) e recuperação (70%). A cromatografia de troca catiônica foi selecionada como terceira etapa do processo, definindo assim um processo de produção e purificação escalonável que possibilitou a obtenção de PspA3 com alto grau de pureza (90%). / The pneumococcal surface protein A (PspA) is indispensable for virulence of S. pneumoniae and it was the first choice as carrier for a new conjugated vaccine against S.pneumoniae. Hence, the purpose of this work was to develop an industrial production and purification process of a recombinant fragment PspA clade 3 (rfPspA3) in E. coli. Fed-batch cultivations in 5 L bioreactors with defined medium were carried out using glucose or glycerol as carbon sources. It was obtained 62 g/L of dry cell weight and 3 g/L of rfPspA3. Cells were disrupted with 96.7% of efficiency by high pressure continuous homogenizer. Centrifugation was defined for the clarification step. The sequence with Q- followed by IMAC-Sepharose yielded the best purity and recovery of rfPspA3 (81 and 70%, respectively). Cation exchange was chosen for the last chromatography. In conclusion, an industrial production and purification process was developed and rfPspA3 was obtained with high purity (90%).

Streptococcus pneumoniae é uma bactéria encapsulada causadora de doenças infecciosas como pneumonia, bacteremia e meningite, infecções essas que estão entre as principais causas de morte entre crianças, idosos e imunodeprimidos, indivíduos que constituem o grupo de risco para tais infecções. A vacinação tem sido a mais eficaz forma de conter tais infecções. A vantagem das vacinas conjugadas em comparação às polissacarídicas é a capacidade de indução de uma resposta imune T-dependente o que garante proteção mesmo ao grupo de risco para infecções por S. pneumonia. A proposta do projeto foi estabelecer um protocolo para obtenção de um conjugado constituído pelo polissacarídeo capsular de S. pneumonia sorotipo 1 (PS1) e pela proteína de superfície pneumocócica A (PspA). A síntese do conjugado empregou uma metodologia inédita para o sorotipo 1. A avaliação da resposta imune humoral induzida pelo conjugado mostrou a indução de IgG anti-PS1 gerada pelas imunizações com o conjugado PS1-PspA. / Streptococcus pneumoniae is an encapsulated bacteria causing infectious diseases such as pneumonia, bacteremia and meningitis, these infections are among the leading causes of death among children, elderly and immunocompromised, who constituting individuals of risk group. The vaccination has been the more effective form to counter these infection. The advantage of conjugated vaccines compared to vaccines polysaccharide, is the ability to induce a T-dependent immune response which provides protection even at risk groups for infection by S. pneumoniae. The project proposal was establish a protocol for obtaining a conjugate consisting of the capsular polysaccharide of S. pneumoniae serotype 1 (PS1) and the pneumococcal surface protein A (PspA). The synthesis of conjugate employed a new methodology for serotype 1. The evaluation of humoral immune response induced by the conjugate showed anti-PS1 IgG induction generated by immunization with the PS1-PspA.

Longtemps décrit comme un simple tissu de réserve énergétique, le tissu adipeux blanc est, depuis l’identification de la leptine en 1994, considéré comme un véritable organe endocrine. En effet, ce tissu secrète de nombreuses hormones et cytokines agissant de manière paracrine et endocrine pour contrôler le métabolisme énergétique. Par ailleurs, en plus des préadipocytes et des adipocytes, le tissu adipeux blanc contient également des cellules immunes innées et adaptatives ; lui conférant ainsi un rôle important dans le développement et le contrôle de l’immunité. Cependant, le rôle joué par le tissu adipeux blanc dans les infections - notamment pulmonaires - reste encore peu étudié. C’est dans ce cadre général que s’est inscrit ce travail de Thèse. La susceptibilité accrue des individus obèses (expansion du tissu adipeux blanc) à l’infection par le virus de la grippe (influenza) est largement étayée dans la littérature. Nous avons évalué l’impact de l’infection par le virus influenza sur le tissu adipeux blanc, chez des souris minces et des souris obèses. Nos résultats montrent que, de manière inattendue, le virus est détecté dans les tissus adipeux, sous-cutané (inguinal) et viscéral (périgonadique), de souris infectées par voie intra-nasale (détection du génome viral par RT-qPCR). La présence de virus dans le tissu adipeux est associée à l’augmentation de la sécrétion de cytokines pro- et anti-inflammatoires, à la diminution de l’expression de gènes impliqués dans la lipolyse et la lipogénèse, et à l’augmentation de l’expression des gènes impliqués dans l’induction d’une réponse immune anti-virale. De manière intéressante, l’infection par le virus influenza est associée au brunissement du tissu adipeux sous-cutané chez les souris minces. Chez les souris obèses, l’infection par le virus de la grippe n’induit pas l’effet dépôt spécifique observé chez la souris mince et ne montre pas de brûnissement au niveau du tissu adipeux sous-cutané 7 jours p.i. In vitro, nous montrons que le virus influenza peut infecter les préadipocytes et les adipocytes (lignée murine et cellules primaires humaines). Cependant, alors que le virus effectue la totalité de son cycle dans l’adipocyte, le préadipocyte libère très peu, voire pas, de nouveaux virions infectieux (PCR, transcriptomique, technique de plages de lyse, microscopie confocale et électronique). Ainsi nos résultats, très originaux, identifient le tissu adipeux blanc comme un nouveau tissu cible de l’infection par le virus de la grippe, in vivo. Au sein de ce tissu, les préadipocytes et les adipocytes sont potentiellement infectés par le virus, comme le montrent nos données in vitro, les adipocytes seuls permettant la production de nouvelles particules infectieuses.Contrairement à l’infection grippale, les données épidémiologiques et/ou expérimentales concernant la susceptibilité des obèses à l’infection par la bactérie Streptococcus pneumoniae sont contradictoires, du fait de l’utilisation de différents modèles d’obésité d’origine génétique et de sérotypes de pneumocoques. Dans ce projet, nous avons utilisé un modèle d’obésité d’origine nutritionnelle ; le modèle de souris nourries par un régime enrichi en lipides. Nous montrons que les souris obèses infectées (sérotype Sp1) développent un syndrome de type méningite, mortel, tandis que les souris minces contrôlent l’infection. Si les réponses pulmonaires à l’infection sont comparables entre les souris minces et obèses (dénombrement des colonies bactériennes, histologie, PCR, ELISA, cytométrie en flux), le nombre de bactéries dans le cerveau est significativement plus élevé chez les souris obèses, associé à une altération de la perméabilité de la barrière hématoencéphalique [...] / Since the identification of leptin in 1994, the white adipose tissue (WAT) is no longer considered to solely be an inert tissue storing fat. As an endocrine organ, the adipose tissue synthesizes and secretes several hormones and cytokines involved in the control of whole-body metabolism. In addition, besides preadipocytes and adipocytes, WAT also contains innate and adaptive immune cells; thereby contributing to the development and control of immunity. However, the role played by the adipose tissue during infections - notably during pulmonary infections, such as those resulting from influenza virus or Streptococcus pneumoniae infections - has barely been investigated. This defines the general scope of this work. Epidemiological and experimental data convincingly report that obese individuals are more susceptible to influenza infection. During this project, we therefore questioned whether influenza infection may impact on adipose tissues, both subcutaneous (inguinal, SCAT) and visceral (perigonadal, EWAT) depots, in lean and high-fat diet-induced obese mice. We unexpectedly showed that influenza virus is detected in SCAT and EWAT (quantification of the viral genome by RtqPCR) and that this was associated with drastic changes in the tissue such as: increased secretion of pro- and anti-inflammatory cytokines, decreased expression of genes involved in lipogenesis and lipolysis, as well as increased expression of genes related to the induction of anti-viral immunity. Interestingly enough, influenza infection was associated with the development of brown-like adipocytes in the SCAT, only in lean animals. Moreover, we demonstrated in vitro that preadipocytes and adipocytes (murine cell-line and human primary cells) are permissive to infection, yet with different outcomes. Indeed, only adipocytes allowed the release of new infectious particles (RtqPCR, transcriptomics, quantification of infectious particules on MDCK cells, confocal and transmission electron microscopy). Altogether, our findings revealed, for the first time, that the white adipose tissue, an organ at the crossroads of metabolism and immunity, is deeply affected by influenza infection and might thus be undervalued in influenza pathophysiology.In opposite to influenza infection, the impact of obesity on the outcome of Streptococcus pneumoniae (S.p.) infection remains uncertain, due to the different models (genetically-based obesity, and bacterial strains) used. During this work, we investigated S. pneumoniae (Sp1 strain, sublethal dose) infection in lean and high-fat diet-induced obese mice. We showed that obese mice died from sublethal S. pneumoniae infection, compared to lean animals. The increased mortality induced by infection did not result from impaired pulmonary response but rather from the development of a meningitis-like syndrom likely resulting from an increased bacterial dissemination through the bloodbrain barrier into the brain. We propose that the model of dietary obesity induced by consumption of fat-enriched diet, may be envisaged as a novel and valuable experimental model of memingitis to study Streptococcus pneumoniae travel through the blood-brain barrier and the subsequent immune consequences.

Introdução: Atualmente a incidência anual de pneumonia adquirida na comunidade nos países em desenvolvimento é de 150,7 milhões de casos entre crianças menores de 5 anos de idade , dos quais 11 a 20 milhões (7-13%) necessitam de internação hospitalar devido à gravidade. O tratamento geralmente é empírico mas o Streptococcus pneumoniae é o principal agente etiológico bacteriano.É necessário manter monitoramento dos sorotipos e padrão de resistência para melhor orientação terapêutica. Metodologia: Estudo de coorte retrospectivo com inclusão de 107 crianças com diagnóstico clínico e radiológico de pneumonia e com isolamento de Streptococcus pneumoniae em sangue e ou líquido pleural no período de janeiro de 2003 a outubro de 2008. Realizado determinação de concentração inibitória mínima (MIC) para penicilina e antibiograma para outros antimicrobianos. A sensibilidade para penicilina utilizada foi conforme Clinical and Laboratory Standards Institute (CLSI ) de 2008. Realizado sorotipagem de 96 cepas de pneumococos (89,7%) e analisados os dados da população em estudo e da evolução clínica. Resultados:Cerca de 47,5% das internações na enfermaria foram por pneumonia ou broncopneumonia e a média de positividade em cultura para pneumococo (sangue e ou líquido pleural) foi de 2,5%. Houve uma sazonalidade bem definida da pneumonia pneumocócica. Cerca de 70% ocorreram nos meses de junho a outubro. A mediana de idade foi de 23 meses (82,2%<5anos); predomínio do sexo masculino (58,9%);utilização de antibioticoterapia nos dois meses prévios à internação de 23,4%; freqüência em creche no menores de 2 anos de 36,4%; apenas um caso com vacinação heptavalente completa; doença associada em 44,9% sendo a mais freqüente a sibilância( 77,1%); tempo de febre e de sintomas respiratórios antes da admissão foi de 4 dias;necessidade de oxigenoterapia não invasiva em 70,1% com tempo médio de utilização de 4 dias;necessidade de ventilação mecânica em 19,6%, mediana do tempo de internação de 9 dias.Em 62% houve complicações sendo as mais freqüentes: empiema (53%) e efusão pleural não complicada (42%). As crianças com empiema tiveram mais pneumonia necrotizante, abscesso pulmonar, sepse, pneumotórax, necessidade de decorticação e ainda maior mortalidade (todas com p<0,05). As crianças com complicações tiveram mais dias de sintomas respiratórios antes da admissão (3x5dias), mais tempo de febre após o início de antibiótico (1x4,5dias), necessitaram de oxigenoterapia não invasiva(58,5x77,3%) e ventilação mecânica (7,3x27,3%) por tempo maior e permaneceram por mais tempo internados (5x12 dias). Das 107 cepas de pneumococo, 100 (93,5%) foram sensíveis à penicilina e 7 (6,5%) de sensibilidade intermediária. Todas as cepas testadas foram sensíveis para rifampicina e vancomicina e ainda mantiveram boa sensibilidade para clindamicina, cloranfenicol, ceftriaxone, eritromicina e levofloxacina. Cinco cepas foram multiresistentes. Notou-se que a média geométrica das concentrações inibitórias mínimas (GMC) para penicilina foram maiores nas crianças com complicações. Os sorotipos mais freqüentes foram: 14(36,5%), 1(16,7%) , 5(14,6%) e 6B(6,3%). O sorotipo 14 apresentou a maior GMC para penicilina e houve um aumento progressivo no decorrer dos anos de estudo. A cobertura dos sorotipos pela vacina heptavalente seria de 53,1% e esta cobertura menor se deve principalmente ao sorotipo 1 e 5, que corresponde a 31,3% dos casos. A cobertura dos sorotipos associados à resistência seria de 94,2%. A cobertura pela vacina 10-valente seria de 86,5% e com a 13-valente seria de 96,9%. Três casos que evoluíram para óbito (2,8%) tinha mediana de idade de 18 meses, todos do sexo masculino, todos com concentração inibitória mínima para penicilina menor ou igual 1g/mL, todos evoluíram com empiema e sepse. Dois foram do sorotipo 5 e um do sorotipo 14. Conclusões: Aproximadamente 2,5% das crianças internadas com diagnóstico de pneumonia foram diagnosticadas como pneumonia pneumocócica.Verificamos uma sazonalidade bem definida.Houve complicações em 62% dos casos. As mais freqüentes foram : empiema e a efusão pleural não complicada. Evidenciou-se uma GMC para penicilina maior nas crianças com complicações comparadas às crianças com ausência de complicações. Os sorotipos mais freqüentes foram 14,1 ,5 e 6B sendo que os sorotipos 1 e 5 totalizam 31,3%. A cobertura pela vacina heptavalente dos sorotipos isolados seria de 53,1%. A sensibilidade para penicilina dos pneumococos isolados de pneumonia foi de 93,5%. Assim, a opção terapêutica continua sendo a penicilina. / Introduction: Currently, the annual incidence of the acquired pneumonia in the developing country communities are around 150.7 million cases, among childrens under 5 years of age, and 11 to 20 million (7-13%) of those require hospitalization due to their gravity. In general, the treatments used to be empirical, however, it is important to be noted that Streptococcus pneumoniae is far the major bacterial etiologic agent. It is necessary to keep monitoring the serotypes and the pattern of resistance in order to improve the therapy guidance. Methodology: Retrospective cohort study with inclusion of the 107 childrens with clinical and radiological diagnosis of the pneumonia, and the isolation of Streptococcus pneumoniae in the blood and/or pleural fluid during the period of January 2003 to October 2008. It was performed determination of the minimum inhibitory concentration (MIC) related to the penicillin and other antibiotics. The sensitivity analysis to the penicillin was based on Clinical and Laboratory Standards Institute (CLSI), 2008, recommendations. They were performed serotyping in 96 pneumococcal strains (89.7%) and they were analyzed datas referred to the considered population and their clinical course. Results: About 47.5% of admissions in the ward were caused by pneumonia or bronchopneumonia, and the average positive occurrences in the pneumococcal (blood and / or pleural) culture were 2.5%. It was noted a clear seasonality phenomena of the pneumococcal pneumonia. About 70% of the cases occurred during months of June to October. The median age was 23 months (82.2%<5 years); with predominance of males (58.9%); in the 23,4% of the cases the antibiotic therapy was used during two months prior to the admission; the daycare frequency of the childs less than 2 years were 36.4%; only one case with complete vaccination heptavalent; associated disease was detected in the 44.9% of the cases and the most frequent was wheezing (77.1%); time of fever and respiratory symptoms before admission were 4 days; the need for noninvasive oxygen therapy occurred in 70.1% being 4 days of the average time of the use; the need for mechanical ventilation occurred in 19.6%; the median period of stay were 9 days. In 62% of the cases there were the most frequent complications: empyema (53%) and non-complicated pleural effusion (42%). The childrens with empyema had more necrotizing pneumonia, lung abscess, sepsis, pneumothorax, need for decortication, and even higher mortality (all with p<0.05). The childrens with complications had more days of respiratory symptoms before admission (3x5days), more time of the fever after initiation with antibiotic (1x4, 5days), they need noninvasive oxygen therapy (58,5 x77, 3%) and mechanical ventilation (7 , 3x27, 3%) for more time and remained hospitalized during longer period(5x12 days). Among 107 pneumococcal strains, 100 (93.5%) were susceptible to penicillin and 7 (6.5%) presented intermediate sensitivity. All strains tested were sensitive to rifampicin and vancomycin, and they maintained good sensitivity to clindamycin, chloramphenicol, ceftriaxone, erythromycin and levofloxacin. Five strains were multi-resistant. It was noted that the geometric mean of minimum inhibitory concentrations (GMC) to penicillin were higher in children with complications. The most frequent serotypes were: 14 (36.5%), 1 (16.7%), 5 (14.6%) and 6B (6.3%). The serotype 14 presented the highest GMC for penicillin and it was verified a progressive increase during the years of the study. The coverage of serotypes by the heptavalent vaccine would be cover 53.1% and this less coverage is represented by serotype 1 and 5, which corresponds to 31.3% of the cases. The coverage of serotypes associated with resistance would be 94.2%. The coverage of the 10-valent vaccine would be 86.5% and for 13-valent would be 96.9%. Three cases that carried to died (2.8%) had median age of 18 months, all they male, all they with minimum inhibitory concentration for penicillin <= 1g/mL, all they progressed to empyema and sepsis. Two of them were serotype 5 and one of them was serotype 14. Conclusions: Approximately 2.5% of children were admitted with diagnosis of pneumonia were diagnosed as pneumococcal pneumonia. It was verified a clear seasonality phenomena. They were observed complications in 62% of the cases. The most frequent were: empyema and non-complicated pleural effusion cases. It was confirmed a higher GMC for penicillin in children with complications compared to the children without complications. The most frequent serotypes were 14, 1, 5 and 6B and the serotypes 1 and 5 accounted 31.3%. The coverage of heptavalent vaccine for the isolated serotypes would be 53.1%. The sensitivity to the penicillin of the isolated pneumococcal was 93.5%. Therefore, the therapy option remains being the penicillin.

La paroi des bactéries à Gram positif se compose du peptidoglycane (PG) et des acides téichoïques (TA). Leur étude a révélé de nouveaux mécanismes de régulation chez le pathogène humain Streptococcus pneumoniae. Nous avons montré que la O-acétylation intervient précocement dans la biosynthèse du PG, participe à sa maturation et à la division cellulaire. Nous avons développé une approche innovante basée sur la chimie click pour le marquage in vivo des TAs, et révélé que leur synthèse est septale et corrélée à celle du PG. Le PG et les TAs contribuent aussi à réguler l'activité enzymatique de l'autolysine majeur du pneumocoque LytA: la O-acétylation du PG protège les cellules en division de l'autolyse par LytA et les TAs, sur lesquels elle se fixe, régulent sa localisation de surface. Pour conclure, ce travail souligne le rôle coopératif du PG et des TAs dans la synthèse de la paroi, la division cellulaire et la régulation de composants de la surface bactérienne. / Gram-positive bacteria cell wall (CW) is composed by peptidoglycan (PG) and teichoic acids (TA). We studied both CW components and revealed new regulation mechanisms in the human pathogen Streptococcus pneumoniae. We showed that PG O-acetylation occurs in the early steps of PG biosynthesis, promotes the formation of mature PG and plays a role in cell division. We developed an innovative click chemistry-based approach to label TA in live cells, opening the way to explore mechanistic issues of pneumococcal TA biosynthesis. We revealed that TA synthesis occurs at the division site and is correlated with PG synthesis. Finally, we showed that both PG and TA polymers contribute to regulate the major autolysin LytA which binds TA and cleaves the PG: the O-acetylation of PG protects dividing cells from LytA-induced autolysis while TA finely regulates LytA surface localization. In conclusion, our work highlights the cooperative role of PG and TA in CW biosynthesis, cell division and regulation of surface components.

Ma, Hok Lun. / Thesis submitted in: December 2008. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 233-273). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract (Chinese version) --- p.v / Tables of contents --- p.vi / Acknowledgement --- p.xvi / List of figures --- p.xvii / List of tables --- p.xxi / List of abbreviations and symbols --- p.xxviii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Respiratory illnesses in children --- p.1 / Chapter 1.1.1 --- Worldwide burden of childhood pneumonia --- p.1 / Chapter 1.1.2 --- Further mortality related to childhood pneumonia --- p.4 / Chapter 1.2 --- Etiology agent of childhood respiratory illnesses --- p.5 / Chapter 1.2.1 --- Difficulties in determining etiological agent --- p.5 / Chapter 1.2.2 --- Overall situation of etiological agents in childhood pneumonia --- p.6 / Chapter 1.2.3 --- Relationship between age and pathogens --- p.9 / Chapter 1.2.4 --- "Relationship between serotypes, carriage and invasiveness" --- p.11 / Chapter 1.2.4.1 --- Carriage and Invasiveness --- p.12 / Chapter 1.2.4.2.1 --- Carriage of S. pneumoniae and H. influenzae in children in Hong Kong --- p.12 / Chapter 1.2.4.2.2 --- "Serotypes, carriage and invasiveness in S. pneumoniae" --- p.14 / Chapter 1.2.4.2.3 --- "Serotypes, carriage and invasiveness in H. influenzae" --- p.17 / Chapter 1.3 --- Epidemiology of antibiotic-resistant pathogens --- p.18 / Chapter 1.3.1 --- Molecular typing methods --- p.18 / Chapter 1.3.2 --- Spread of antibiotic-resistant pathogens --- p.20 / Chapter 1.3.2.1 --- Spread of antibiotic-resistant S. pneumoniae --- p.26 / Chapter 1.3.2.1.1 --- Spread of penicillin-resistant S. pneumoniae --- p.26 / Chapter 1.3.2.1.1.1 --- Spread of Spanish-23F-1 --- p.27 / Chapter 1.3.2.1.1.2 --- Spread of Spanish-6B-2 --- p.28 / Chapter 1.3.2.1.1.3 --- Spread of antibiotic-resistant S. pneumoniae clones in Hong Kong --- p.28 / Chapter 1.3.2.1.2 --- Spread of cephalosporin-resistant S. pneumoniae --- p.29 / Chapter 1.3.2.1.3 --- Spread of macrolide-resistant S. pneumoniae --- p.30 / Chapter 1.3.2.1.4 --- Spread of fluoroquinolone-resistant S. pneumoniae --- p.31 / Chapter 1.3.2.2 --- Spread of antibiotic-resistant H. influenzae --- p.32 / Chapter 1.3.2.2.1 --- Spread of β-lactam-resistant H. influenzae --- p.32 / Chapter 1.3.2.2.2 --- Spread of macrolide-resistant H. influenzae --- p.33 / Chapter 1.3.2.2.3 --- Spread of fluoroquinolone-resistant H. influenzae --- p.34 / Chapter 1.4 --- Mechanism of antibiotic-resistance in respiratory pathogens --- p.36 / Chapter 1.4.1 --- Mechanism of antibiotic-resistance in S. pneumoniae --- p.37 / Chapter 1.4.1.1 --- Mechanism of penicillin- and cephalosporin-resistance in S. pneumoniae --- p.37 / Chapter 1.4.1.1.1 --- Penicillin-binding protein (PBP)-mediated mechanism --- p.37 / Chapter 1.4.1.1.2 --- PBP-independent mechanisms --- p.49 / Chapter 1.4.1.1.2.1 --- "Murine peptide branching genes, murMN operon" --- p.49 / Chapter 1.4.1.1.2.2 --- "Two-component system, CiaRH" --- p.50 / Chapter 1.4.1.1.2.3 --- "Putative glycosyltransferase, CpoA" --- p.52 / Chapter 1.4.1.1.3 --- RNA and protein expression studies on S. pneumoniae for β-lactam-resistance --- p.52 / Chapter 1.4.1.1.3.1 --- RNA expression in penicillin-sensitive S. pneumoniae --- p.53 / Chapter 1.4.1.1.3.2 --- Protein expression in penicillin-resistant S. pneumoniae --- p.53 / Chapter 1.4.1.2 --- Mechanism of macrolide- and lincosamide- resistance in S. pneumoniae --- p.54 / Chapter 1.4.1.3 --- Mechanism of tetracycline-resistance in S. pneumoniae --- p.55 / Chapter 1.4.1.4 --- Mechanism of fluoroquinolone-resistance in S. pneumoniae --- p.55 / Chapter 1.4.2 --- Mechanism of antibiotic-resistant in H. influenzae --- p.56 / Chapter 1.4.2.1 --- Mechanism of β-lactam-resistance in H. influenzae --- p.56 / Chapter 1.4.2.1.1 --- β-lactamase-producing H. influenzae --- p.56 / Chapter 1.4.2.1.2 --- β-lactamase-negative ampicillin-resistant (BLNAR) H. influenzae --- p.58 / Chapter 1.4.2.1.2.1 --- Relationship between amino acid substitutions in PBP3 and β-lactam- resistance --- p.58 / Chapter 1.4.2.1.2.2 --- Relationship between amino acid substitutions in AcrR and β-lactam-resistance --- p.60 / Chapter 1.4.2.2 --- Mechanism of macrolide-resistance in H. influenzae --- p.61 / Chapter 1.4.2.3 --- Mechanism of fluoroquinolone-resistance in H. influenzae --- p.64 / Chapter 1.5 --- Impact of vaccination --- p.65 / Chapter 1.5.1 --- H. influenzae type b vaccination --- p.65 / Chapter 1.5.1.1 --- Efficacy of Hib conjugate vaccine --- p.66 / Chapter 1.5.1.2 --- Herd immunity related to Hib conjugate vaccine --- p.66 / Chapter 1.5.2 --- Pneumococcal vaccination --- p.66 / Chapter 1.5.2.1 --- Vaccine efficacy and herd immunity of pneumococcal vaccines --- p.67 / Chapter 1.5.2.2 --- Development of conjugate vaccines with higher valency --- p.67 / Chapter 1.5.2.3 --- Serotype replacement --- p.67 / Chapter 1.5.2.4 --- Development of pneumococcal vaccines with new targets --- p.69 / Chapter 1.6 --- Objectives of this study --- p.70 / Chapter Chapter 2 --- Materials and methods --- p.72 / Chapter 2.1 --- Collection and Identification of microorganisms --- p.72 / Chapter 2.1.1 --- Collection of S. pneumoniae and H. influenzae --- p.72 / Chapter 2.1.2 --- Identification of S. pneumoniae and H. influenzae --- p.73 / Chapter 2.2 --- Serotyping of S. pneumoniae and H. influenzae --- p.74 / Chapter 2.2.1 --- Serotyping by polymerase chain reaction (PCR) --- p.74 / Chapter 2.2.1.1 --- Preparation of crude DNA extract --- p.74 / Chapter 2.2.1.2 --- Screening for common serotypes by multiplex PCR --- p.74 / Chapter 2.2.1.3 --- Composition of PCR Mix --- p.77 / Chapter 2.2.1.4 --- Serotyping PCR conditions --- p.81 / Chapter 2.2.1.5 --- Gel Electrophoresis --- p.81 / Chapter 2.2.2 --- Serotyping by serum agglutination --- p.82 / Chapter 2.3 --- Antimicrobial susceptibility testing --- p.83 / Chapter 2.4 --- Clonal analysis of penicillin- and cephalosporin-resistant S. pneumoniae --- p.87 / Chapter 2.4.1 --- Pulsed-field Gel Electrophoresis (PFGE) --- p.87 / Chapter 2.4.1.1 --- Preparation of agarose plugs for PFGE --- p.87 / Chapter 2.4.1.2 --- Lysis of bacteria in agarose plugs --- p.89 / Chapter 2.4.1.3 --- Digestion of chromosomal DNA by restriction enzyme --- p.89 / Chapter 2.4.2 --- Multi-locus sequence typing (MLST) --- p.90 / Chapter 2.4.2.1 --- PCR amplification of house-keeping genes in MLST --- p.90 / Chapter 2.4.2.1.1 --- Preparation of DNA from agarose plugs --- p.92 / Chapter 2.4.2.1.2 --- Composition of PCR Mix --- p.92 / Chapter 2.4.2.1.3 --- MLST PCR conditions --- p.92 / Chapter 2.4.2.1.4 --- Gel Electrophoresis of MLST PCR products --- p.92 / Chapter 2.4.2.1.5 --- MLST PCR products purification --- p.93 / Chapter 2.4.2.2 --- Sequencing of housekeeping genes in MLST --- p.93 / Chapter 2.4.2.3 --- Sequencing analysis and sequence type (ST) determination in MLST --- p.94 / Chapter 2.4.3 --- Extended panel of antibiotic susceptibility testing on S. pneumoniae with known STs --- p.94 / Chapter 2.5 --- Analysis on potential penicillin- and cephalosporin-resistance mechanisms in S. pneumoniae --- p.96 / Chapter 2.5.1 --- Sequencing of potnetial penicillin- and cephalosporin- resistance determinants in S. pneumoniae --- p.96 / Chapter 2.5.1.1 --- Primer design of penicillin-binding protein (PBP) genes --- p.96 / Chapter 2.5.1.2 --- Primer design of non-PBP resistance determinants --- p.100 / Chapter 2.5.1.3 --- PCR amplification and sequencing of resistant determinants --- p.100 / Chapter 2.5.1.4 --- Sequence analysis --- p.100 / Chapter 2.5.2 --- Study on efflux mechanism of S. pneumoniae --- p.103 / Chapter 2.5.2.1 --- Modification of macrodilution for efflux assay --- p.103 / Chapter 2.5.2.2 --- Cefotaxime MIC determination with efflux inhibitors --- p.104 / Chapter 2.5.2.3 --- Determination of appropriate CCCP concentration --- p.105 / Chapter 2.5.2.4 --- Growth curve with efflux inhibitor --- p.105 / Chapter 2.5.3 --- Heteroresistance assay of S. pneumoniae --- p.106 / Chapter 2.5.4 --- "RNA expression study on penicillin- and cefotaxime-resistance determinants (pbp2x, pbpla and pbp2a) of S. pneumoniae" --- p.107 / Chapter 2.5.4.1 --- Growth of S. pneumoniae for RNA extraction --- p.107 / Chapter 2.5.4.2 --- RNA extraction and DNase digestion --- p.107 / Chapter 2.5.4.3 --- cDNA synthesis and real-time PCR --- p.108 / Chapter 2.6 --- Analysis on cephalosporin- and macrolide-resistance mechanisms in H. influenzae --- p.111 / Chapter 2.6.1 --- β-lactamase production of H. influenzae --- p.111 / Chapter 2.6.1.1 --- Nitrocefin Hydrolysis --- p.111 / Chapter 2.6.1.2 --- Screening for the presence of p-lactamase gene (blaTEM-1 and blaROB-1) by multiplex PCR --- p.111 / Chapter 2.6.2 --- PCR detection and sequencing of β-lactam- and macrolide- resistance determinants in H. influenzae --- p.113 / Chapter Chapter 3 --- Results of S. pneumoniae and H. influenzae children study --- p.116 / Chapter 3.1 --- Patient demographics of children study --- p.116 / Chapter 3.2 --- Serotype distributions --- p.117 / Chapter 3.2.1 --- Serotypes / serogroup distribution in S. pneumoniae --- p.117 / Chapter 3.2.2 --- Serotype distribution in H. influenzae children study --- p.120 / Chapter 3.3 --- Antibiotic susceptibilities and resistance antibiograms --- p.122 / Chapter 3.3.1 --- Antibiotic susceptibilities of S. pneumoniae --- p.122 / Chapter 3.3.2 --- Relationship between antibiotic resistance profiles and serotypes in S.pneumoniae --- p.126 / Chapter 3.3.3 --- Antibiotic susceptibilities of H. influenzae --- p.135 / Chapter 3.3.4 --- Antibiotic resistance profiles of H. influenzae --- p.138 / Chapter 3.4 --- Clonal analysis of penicillin- and cephalosporin-resistant S.pneumoniae --- p.139 / Chapter 3.4.1 --- Pulsed-field gel electrophoresis (PFGE) of S. pneumoniae --- p.139 / Chapter 3.4.2 --- Multi-locus sequence typing of S. pneumoniae --- p.141 / Chapter 3.5 --- Analysis of the penicillin- and cephalosporin-resistance determinants in S. pneumoniae --- p.143 / Chapter 3.5.1 --- "Sequence analysis of major pbp genes (pbp2x, pbpla and pbp2a)" --- p.143 / Chapter 3.5.2 --- "Sequence analysis of other potential penicillin- and cephalosporin- resistance determinants (pbp 1 b, pbp2b, pbp3, cpoA, ciaRH and murMN)" --- p.152 / Chapter 3.5.3 --- Sequence analysis of putative promoter sequences of pbp genes --- p.167 / Chapter 3.5.4 --- Efflux Inhibition Assay --- p.171 / Chapter 3.5.5 --- Heteroresistance Assay --- p.177 / Chapter 3.5.6 --- "RNA expression study on penicillin- and cephalosporin resistance determinants (pbp2x, pbpla and pbp2a)" --- p.179 / Chapter 3.6 --- Analysis of β-lactam-resistance determinants in H. influenzae --- p.185 / Chapter 3.6.1 --- β-lactamase production and blaTEM-1 promoter study --- p.185 / Chapter 3.6.2 --- "Sequence analysis of β-lactam-resistance determinants (ftsl, acrR genes, AcrAB-TolC efflux pump)" --- p.188 / Chapter 3.6.2.1 --- Sequence analysis offtsl --- p.188 / Chapter 3.6.2.2 --- Analysis of acrR and AcrAB-TolC efflux pump --- p.189 / Chapter 3.7 --- "Analysis of macrolide-resistance determinants in H, influenzae (AcrAB-TolC efflux pump, 23SrRNA, Ribosomal proteins L4 and L22)" --- p.199 / Chapter Chapter 4 --- Discussion on S. pneumoniae and H. influenzae children study --- p.204 / Chapter 4.1 --- Carriage rate of S. pneumoniae children collection --- p.204 / Chapter 4.2 --- Serotype distribution --- p.205 / Chapter 4.2.1 --- Serotype distribution and potential vaccine coverage in S. pneumoniae --- p.205 / Chapter 4.2.2 --- Serotype distribution in H. influenzae --- p.209 / Chapter 4.3 --- Antimicrobial resistance --- p.210 / Chapter 4.3.1 --- Antimicrobial resistance in S. pneumoniae --- p.210 / Chapter 4.3.2 --- Antimicrobial resistance in H. influenzae --- p.214 / Chapter 4.4 --- "Clonal analysis of high-level β-lactam-resistant S, pneumoniae" --- p.217 / Chapter 4.5 --- "β-lactam-resistance mechanisms in S, pneunomiae" --- p.220 / Chapter 4.6 --- Antimicrobial resistance mechanisms in H. influenzae --- p.224 / Chapter 4.6.1 --- β-lactam-resistance mechanism in β-lactamase-producing H. influenzae --- p.224 / Chapter 4.6.1.1 --- Variations in blaTEM-1 promoters in β-lactamase-producing H.influenzae --- p.224 / Chapter 4.6.1.2 --- β-lactam-resistance in β-lactamase-nonproducing H. influenzae --- p.225 / Chapter 4.6.2 --- Macrolide-resistance mechanisms in H. influenzae --- p.228 / Chapter Chapter 5 --- Conclusion and future studies --- p.230 / Chapter 5.1 --- "S, pneumoniae children study" --- p.230 / Chapter 5.2 --- H. influenzae children study --- p.231 / Chapter 5.3 --- Future studies --- p.232 / Bibliography --- p.233 / Appendix I 一 Sequence alignments and Tables --- p.274 / Appendix II 一 Materials and Methods --- p.313

No description available.

Streptococcus pneumoniae ist der häufigste Erreger bakterieller Meningitiden. Eine Pneumokokken-Meningitis führt trotz Ausschöpfung aller heute verfügbaren Behandlungsmöglichkeiten in 25 % der Fälle zum Tod. Steigende Antibiotikaresistenzen und die Limitation verfügbarer Vakzine auf einige Serotypen von S. pneumoniae erfordern neue Ansätze in der antimikrobiellen Therapie. Cholin-bindende Proteine (CBPs) sind gemeinsames Merkmal aller Pneumokokkenstämme und für die Virulenz dieses Bakteriums essenziell. Durch Zugabe potenter Anticholinergika können die CBPs von der Bakterienoberfläche abgelöst und damit inhibiert werden. In dieser Arbeit wurde untersucht, ob durch Inhibition von CBPs während des Wachstums der Pneumokokken deren Phagozytose durch Mikrogliazellen in vitro gesteigert werden kann. Während ihres Wachstums wurden die Bakterien dazu mit potenten Anticholinergika inkubiert und am Ende ihrer exponentiellen Wachstumsphase auf murine Mikrogliazellen gegeben. Nicht alle eingesetzten Anticholinergika konnten die Inhibition der CBPs – angezeigt durch die Bildung langer Kokkenketten – bewirken, obwohl für sie alle eine hohe Affinität zu den CBPs in früheren Arbeiten nachgewiesen worden war. Ipratropium, das in höheren Konzentrationen das Pneumokokkenwachstum inhibiert, induzierte in den von uns eingesetzten niedrigen Konzentrationen weder die Bildung von Ketten noch führte es zu einer erhöhten Phagozytoseleistung. Mit DMAE funktionalisiert zeigten PAMAM-Dendrimere der 1. Generation ebenfalls keine Inhibition der CBPs: Es bildeten sich weder Kokkenketten noch zeigte sich eine erhöhte Bakterienaufnahme der Mikroglia. Im Gegensatz dazu stellte sich unter Einfluss von PPI-g2-DMAE neben ausbleibender Kettenbildung ein dosisabhängiger phagozytosehemmender Effekt dar. Einzig durch Co-Inkubation mit dem mit Cholin funktionalisierten PPI-Dendrimer der 2. Generation gelang die Inhibition der CBPs mit resultierender Bildung langer Ketten. Die Phagozytoseleistung zeigte eine dosisabhängige Steigerung sowohl für eine CoInkubation während der gesamten exponentiellen Wachstumsphase als auch nach Co-Inkubation während ihrer letzen 2 Stunden. Dennoch konnte im Sepsismodell der Maus durch intraperitoneale Injektion dieses Dendrimers 15 min vor Infektion mit S. pneumoniae kein protektiver Effekt erzielt werden: Zwischen den mit Dendrimeren behandelten Tieren und denen der Kontrollgruppe zeigten sich keine Unterschiede in Überlebenszeit und Sterblichkeit, dem krankheitsbedingten Gewichtsverlust, dem klinischen Score und der durch Ausplattieren von Milzhomogenaten ermittelten Keimkonzentration im Blut infektionsbedingt verstorbener Tiere. Die von uns eingesetzten Konzentrationen von Ipratropium scheinen für eine Inhibition der CBPs nicht ausgereicht zu haben. Der bislang nicht genau geklärte wachstumsinhibitorische Effekt, der sich in unseren Versuchen bereits ab 5 mM bemerkbar machte, könnte jedoch durch Inhalation von Ipratropium gezielt zur Prophylaxe von Pneumokokken-Pneumonien genutzt werden. Bei an Dendrimere gekoppelten, eigentlich potenten Liganden der CBPs konnte beobachtet werden, dass sie als Teil des Dendrimers ihre Affinität gegenüber den CBPs nicht nur deutlich verändern, sondern auch unerwartete Effekte (Verminderung der Phagozytose) hervorrufen können. Wegen der raschen Elimination scheint die einmalige Gabe eines potenten Dendrimers zur Inhibition der CBPs in vivo nicht auszureichen und erklärt das Versagen im Sepsismodell. Neuere Untersuchungen zur Distribution im Hirnparenchym nach intraventrikulärer oder subarachnoidaler Injektion lassen hoffen, dass durch Gabe subtoxischer Dosen die von uns beobachtete Phagozytosesteigerung in vivo reproduzierbar ist. Durch Inhibition der CBPs ist es möglich, die Virulenz aller Serotypen des Pneumokokkus stark zu reduzieren. Potente Inhibitoren könnten sowohl als Therapeutikum als auch zur Infektionsprophylaxe eingesetzt werden, ohne dass es dabei zur Ausbildung von Resistenzen kommt, da zeitgleich mehrere Virulenzfaktoren inhibiert werden. Es ist daher von großem medizinischen Interesse, Inhibitoren der CBPs zu entwickeln, die in subtoxischen Dosen eine hohe Affinität zu den CBPs aufweisen und diese inhibieren.