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La broncho-pneumopathie chronique obstructive (BPCO) est une maladie inflammatoire chronique des voies aériennes dont le facteur de risque principal est l’exposition chronique à la fumée de cigarette. L’histoire de la maladie est fréquemment associée à une colonisation bactérienne des voies aériennes et ponctuée d’épisodes aigus d’exacerbation de la maladie associés à une morbi-mortalité importante. Ces exacerbations sont principalement d’origine infectieuses et plus particulièrement, associées à une bactérie dans 50 % des cas, majoritairement Haemophilus influenzae, Streptococcus pneumoniae et Moraxella catarrhalis. Le contrôle de ces infections bactériennes implique en particulier une réponse immunitaire de type Th17 efficace. Cette immunité Th17 médiée principalement par les cytokines IL-17A et IL-22 est impliquée dans la physiopathologie de la BPCO mais n’a été que peu étudiée dans le contexte des exacerbations. Notre hypothèse est que la réponse Th17 aux pathogènes est altérée dans la BPCO, mécanisme qui serait impliqué dans la susceptibilité aux infections respiratoires observée chez les patients.Différentes approches ont été utilisées pour tester cette hypothèse. Tout d’abord, une approche ex vivo, à partir de cellules mononucléées circulantes (PBMC) de patients atteints de BPCO comparées à celles issues de sujets sains non fumeurs et de sujets fumeurs sans obstruction bronchique, montrant un défaut de production par les PBMC des cytokines IL-17A et IL-22 mais également des cytokines IL-6 et IL-23 produites par les cellules présentatrices d’antigènes (CPA) et impliquées dans l’activation de cette immunité Th17, en réponse à une activation par S. pneumoniae. Ensuite, une approche in vitro, avec un modèle de cellules dendritiques dérivées de monocytes (MDDC) exposées à la fumée de cigarette. Ces MDDC présentaient un défaut de maturation, de production de cytokines pro-Th17 et de leur capacité à activer une réponse Th17 lymphocytaire en réponse à S. pneumoniae. Enfin, une approche in vivo, utilisant un modèle murin de souris exposées de façon chronique à la fumée de cigarette confirmant ces résultats avec un défaut de réponse IL-17A et IL-22 mais également de production des cytokines pro-Th17 IL-1β et IL-23 par les CPA en réponse à S. pneumoniae. Dans ce modèle, l’apport d’IL-22 permettait d’améliorer la clairance bactérienne et de réduire les lésions pulmonaires, suggérant des possibilités thérapeutiques pour améliorer la prise en charge de ces exacerbations infectieuses.Ces trois approches permettent d’apporter des arguments forts en faveur d’un défaut de réponse Th17 au cours des exacerbations bactériennes de la BPCO, hypothèse confortée par d’autres travaux de notre équipe montrant dans le modèle murin d’exposition chronique à la fumée de cigarette la présence d’un défaut de production d’IL-22 dans la réponse à Haemophilus influenzae. Ces travaux qui doivent maintenant être d’une part, confirmés par une étude clinique incluant des patients atteints de BPCO en exacerbation, et d’autre part, complétés pour préciser l’impact sur les cellules lymphoïdes innées productrices de ces cytokines et sur la réponse de l’épithélium bronchique à l’infection, ouvrent la voies à des perspectives thérapeutiques dans la prise en charge de ces exacerbations bactériennes. / Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease of the airways mainly due to chronic exposure to cigarette smoke. Evolution of the disease is often associated with bacterial colonization of the airways and punctuated by acute exacerbation of the disease with a frequent related morbi-mortality. These exacerbations are mainly due to infection and almost 50 % are associated with bacteria, often Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis. Th17 immune response is particularly involved in control of bacterial infection and is principally mediated by IL-17A and IL-22 cytokines. This Th17 inflammation is involved in COPD physiopathology but there is paucity of data focusing on this immune response during COPD exacerbations. Our hypothesis is that Th17 immune response to pathogens is defective in COPD leading to airways infection susceptibility.We have tested our hypothesis by different approaches. First, the ex vivo responses to Streptococcus pneumoniae of peripheral blood mononuclear cells (PBMC) from COPD patients, healthy non smokers and healthy smokers were compared showing decreased production of IL-17A and IL-22 but also of pro-Th17 cytokines IL-6 and IL-23 which are produced by antigen presenting cells (APC). Second, we used an in vitro model of monocyte-derived dendritic cells (MDDC) exposed to cigarette smoke showing a defective MDDC maturation, pro-Th17 cytokines production and ability to promote T-cells Th17 response, in response to S. pneumoniae. Finally, an in vivo murine model of mice chronically exposed to cigarette smoke showing defective production of IL-17A and IL-22 but also of pro-Th17 cytokines IL-1β and IL-23 produced by APC, in response to S. pneumoniae. In this model, supplementation with IL-22 restored bacterial clearance and limited lung alterations suggesting therapeutic opportunities to improve infectious COPD exacerbation management.Altogether, these results strengthen our hypothesis of a defective Th17 immune response during bacterial COPD exacerbations. They are comforted by other studies in our team showing a defective IL-22 production in response to Haemophilus influenzae in our in vivo model of mice chronically exposed to cigarette smoke. Now we have to confirm these results in a clinical trial including COPD patients in exacerbation and to further explore the impact on innate lymphoid cells, which produced these cytokines, and on the innate immune response of epithelial cells to infection, in order to develop new infectious COPD exacerbation therapeutics.

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2012-07-20T21:34:48Z No. of bitstreams: 1 Larissa Carneiro Rocha.pdf: 1632038 bytes, checksum: 82deed6171da78f07c96b948629b2896 (MD5) / Made available in DSpace on 2012-07-20T21:34:48Z (GMT). No. of bitstreams: 1 Larissa Carneiro Rocha.pdf: 1632038 bytes, checksum: 82deed6171da78f07c96b948629b2896 (MD5) Previous issue date: 2011 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, Bahia, Brasil / A doença falciforme (DF) possui prevalência mundial elevada e manifestação clinicamente variável, sendo que as infecções constituem risco elevado e causa de óbito nas crianças diagnosticadas com anemia falciforme (HbSS). A colonização da nasofaringe pode ser fator importante para a ocorrência de doença local ou sistêmica. O Streptococcus pneumoniae é um patógeno de importância epidemiológica mundial e causador de infecções entre os pacientes com DF. A prevalência da colonização pelo pneumococo em nasofaringe varia de acordo com a população estudada e condições ambientais. O Staphylococcus aureus também pode colonizar a nasofaringe, além de causar infecção de pele e tecidos moles, pneumonia, septicemia e infecções ósteo-articulares. Diferentes biomarcadores têm sido associados à modulação clínica na DF e eles são comumente associados à hemólise e inflamação. O presente estudo teve como objetivo estabelecer o perfil de biomarcadores em indivíduos com DF associando-os ao perfil de colonização nasofaríngea e orofaríngea, com ênfase para os marcadores de infecção e hemólise que possam estar associados ao prognóstico clínico dda doença. As análises bioquímicas foram realizadas para a avaliação do perfil lipídico, hepático, inflamatório e hemolítico; marcadores clássicos de biologia molecular, como a talassemia α, os haplótipos ligados aos genes da globina beta e os polimorfismos no gene da mieloperoxidase foram também investigados. Desta forma, foi desenvolvido um estudo de corte transversal, com casuística composta por 154 pacientes com DF em idade pediátrica e em estado estável da doença, sendo 68,2% (105/154) HbSS e 31,8% (49/154) com doença SC (HbSC), todos provenientes do estado da Bahia. As crianças HbSS apresentaram diferenças significativas na grande maioria das variáveis laboratoriais analisadas e associadas ao metabolismo lipídico, renal, hepático e à hemólise e inflamação, quando comparadas ao grupo HbSC e ao controle saudável. A colonização em nasofaringe/orofaringe pelo S. pneumoniae esteve presente em 14 (9,6%) pacientes e pelo S. aureus em 81(56,6%) pacientes. Quanto ao perfil de sensibilidade dos isolados de pneumococos da população estudada, não foi observado o aumento da resistência pneumocócica à penicilina. A avaliação de modelos de análise multivariada demonstrou que a presença de colonização nasofaríngea e orofaríngea esteve associada à ocorrência de infecção juntamente com a contagem de leucócitos, sendo que o genótipo exibido pelo paciente foi fator de risco para a ocorrência de pneumonia. Os mesmos modelos apontaram o envolvimento dos polimorfonucleares neutrófilos na ocorrência de vaso-oclusão. Os resultados demonstram que os pacientes colonizados em nasofaringe pelo S. pneumoniae e pelo S. aureus apresentaram elevação dos valores de HCM, VCM, AST, ALT e Ferritina; investigações rotineiras de biomarcadores clássicos associados ao estudo da colonização de nasofaringe e orofaringe podem ter papel importante no acompanhamento da evolução clinica de indivíduos com DF, uma vez que os achados significativos sugerem que a presença de colonização tem papel importante na modulação dos eventos hemolítico, inflamatório e infeccioso presentes na doença. / The sickle cell disease (SCD) has a high prevalence worldwide and a variable clinical manifestation and infections are considered an event of high risk and cause of death in children diagnosed with sickle cell anemia (HbSS). The colonization of nasopharynx and oropharynx can be an important factor for the occurrence of local or systemic disease. The Streptococcus pneumoniae is a pathogen of epidemiological importance worldwide and cause of infection among SCD patients. The Staphylococcus aureus may also colonize the nasopharynx and may be cause of infection of skin and soft tissue infections, pneumonia, sepsis and osteo-articular infections. Different biomarkers have been associated with clinical modulation in SCD and they are commonly associated with hemolysis and inflammation. This study aimed to establish a profile of biomarkers in individuals with SCD in association with the profile of oropharyngeal and nasopharyngeal colonization, with emphasis on infection and hemolysis markers that may be associated with clinical prognosis. Biochemical analysis were performed to evaluate the lipid profile, liver, hemolytic and inflammatory markers and classical molecular biology, such as α-thalassemia, the haplotypes linked to the beta globin genes and polymorphisms in the myeloperoxidase gene were also investigated. Thus, it was developed a cross-sectional study and the casuistic was composed of 154 children with SCD in a steady-state, with 68.2% (105/154) HbSS and 31.8% (49/154) with SC disease (HbSC), all from the state of Bahia. HbSS children showed significant differences in almost every mean values analyzed for variables associated with lipid metabolism, kidney, liver and hemolysis and inflammation when compared to HbSC and control group. In the present study there was colonization in the nasopharynx / oropharynx by S. pneumoniae in 14 (9.6%) patients and by S. aureus in 81 (56.6%) patients. The profile of sensitivity of pneumococcal isolated from the studied population did not show an increase in pneumococcal resistance to penicillin. The evaluation of models of multivariate analysis showed that the presence of oropharyngeal and nasopharyngeal colonization was associated with the occurrence of infection and white blood cell count, and the patient genotype was a risk factor for the occurrence of pneumonia. The same models indicated the involvement of polymorphonuclear neutrophils in the occurrence of vaso-occlusion. The results presented in this study demonstrate that patients colonized in the nasopharynx by S. pneumoniae and S. aureus have elevated values of MCH, MCV, AST, ALT and ferritin, suggesting that a routine investigation of biomarkers associated with the classic study of the colonization of the nasopharynx and oropharynx may play a role in monitoring the clinical course of patients with SCD, once that significant findings described here suggest that the presence of colonization plays an important role in modulation of hemolytic events, inflammatory state, and infectious presented by patients.

Streptococcus pneumoniae, le pneumocoque, est une bactérie pathogène qui entraîne le décès de plus d'un million et demi de personnes dans le monde chaque année. Les β-lactamines sont très utilisées pour traiter les infections à pneumocoques. Ces antibiotiques inhibent la synthèse du peptidoglycane, une molécule géante constituant un réseau de chaînes glycopeptidiques qui englobe la cellule, lui confère sa forme et lui permet de maintenir son intégrité face à la pression osmotique. Le mécanisme d'action des β-lactamines est bien connud'un point de vue biochimique. En revanche, la réponse physiologique empêchant la multiplication des bactéries traitées est mal connue. Au cours de ma thèse, j'ai étudié les mécanismes moléculaires de la morphogenèse du pneumocoque par des approches de biochimie et de microbiologie. Un modèle de morphogenèse est proposé intégrant mes résultats à la littérature et permettant de formuler des hypothèses sur la réponse physiologique de S. pneumoniae aux β-lactamines. / Streptococcus pneumoniae, the pneumococcus, is a bacterial pathogen that causes more than 1.5 million deaths each year in the world. β-Lactams are widely used to treat patients with pneumococcal infections. These antibiotics inhibit the synthesis of the peptidoglycan, a giant molecule constituting a mesh of aminosugar strands encasing the cell. This main constituent of the cell wall allows cells to maintain their integrity under the turgor pressure, and endows bacteria with their shape. The action of β-lactams is well understood from a biochemical point of view. However, a complete understanding of the physiological response of treated bacteria remains elusive. In this thesis, I investigated the molecular mechanisms of the morphogenesis of S. pneumoniae using methods of biochemistry and microbiology. A morphogenesis model is built based on my results and the literature, which permits to emit hypotheses concerning the response of the pneumococcus to β-lactams.

Afin de faire face à différents types de stress et s'adapter à de nouveaux environnements, les bactéries ont développé de nombreux mécanismes génétiquement régulés. La compétence pour la transformation naturelle est un processus qui favorise le transfert horizontal de gènes. Si les espèces phylogénétiquement éloignées partagent des mécanismes conservés d'intégration et de remaniement de l'ADN, les circuits de régulation de la compétence ne sont toutefois pas universels mais adaptés au mode de vie de chaque espèce. Chez les bactéries Gram-positives, les cascades de régulation de Streptococcus pneumoniae et Bacillus subtilis sont les mieux documentées. Si de nombreux modèles mathématiques ont été établis pour étudier différents aspects de la régulation des compétences chez B. subtilis, un seul modèle à échelle de population a été développé pour S. pneumoniae, il y a plus de dix ans, sur la base d'hypothèses contestées par de nouvelles données expérimentales. Nous avons développé, chez S. pneumoniae, un modèle fondé sur la connaissance de la régulation de la compétence qui intègre les éléments biologiques essentiels connus à ce jour. La cohérence structurelle de la topologie du réseau est confirmée par le formalisme des réseaux de Petri. Le réseau est ensuite transformé en un ensemble d'équations différentielles ordinaires pour étudier son comportement dynamique. La cinétique des protéines a été estimée en utilisant des données de luminescence et l'estimation des paramètres a été contrainte à partir des connaissances disponibles. Après avoir testé des modèles alternatifs, nous avons proposé l'existence d'un produit de gène tardif supplémentaire pouvant inhiber l'action de ComW, l'activateur du facteur sx. Nous apportons également un nouvel éclairage sur cette cascade de régulation en prédisant la cinétique de composantes du système qui pourraient être impliquées dans des comportements spécifiques. Ce modèle consolide les connaissances expérimentales acquises sur la régulation de la compétence chez S. pneumoniae. De plus, il peut être appliqué aux autres espèces de streptocoques appartenant aux groupes mitis et anginosus puisqu'ils partagent le même circuit régulateur. À l'échelle populationnelle, la transition vers l'état de compétence se produit d'abord dans une sous-population de cellules et se propage ensuite dans toute la population par contact physique cellule à cellule. En permettant la simulation du comportement d'une cellule individuelle, le modèle pourra servir de module dans la conception d'un modèle d'une population bactérienne composée de cellules hétérogènes. / Bacteria have evolved many types of genetically induced mechanisms to face different types of stresses and to adapt to new environments. Competence for natural transformation is one such process that promotes horizontal gene transfer. If phylogenetically distant species share conserved uptake and processing apparatus, competence regulatory circuits are not universal but adapted to every species' lifestyle. In Gram-positive bacteria, Streptococcus pneumoniae and Bacillus subtilis regulatory cascades are the best documented. If many mathematical models have been established to study different aspects of competence regulation in B. subtilis, only one population-scaled model has been developed for S. pneumoniae, a decade ago, based on hypotheses that are challenged by new experimental data. We develop, in S. pneumoniae, a knowledge-based model of the competence regulation at cell level that integrates the enriched biological knowledge acquired to date. The structural consistency of the network topology is confirmed using Petri net formalism. The network is further turned into a set of ordinary differential equations to study its dynamics behavior. Protein kinetics are estimated using time-series luminescence data and other parameter estimations are constrained according to available knowledge. We point out some gap in competence shut-off knowledge, and, after testing alternative models, we predict the requirement of a yet unknown late com gene product inhibiting the action of ComW, the ?x factor activator. We also bring new insights into this regulatory cascade by predicting the system components that might be involved in specific experimental behavior. Our model consolidates the experimental knowledge acquired on competence regulation in S. pneumoniae. Moreover, it can be applied to the other streptococci species belonging to the mitis and anginosus groups since they shared the same regulatory circuit. In the population, the competence shift happens first in a subpopulation of cells and spreads into the whole population through cell to cell contact. Allowing simulation of individual cell behavior, our model will provide a brick for the design of a population-scale model composed of heterogeneous cells.

A proteína A de superfície de pneumococo (PspA) é encontrada na superfície de todas as cepas de Streptococcus pneumoniae e candidata promissora para novas vacinas pneumocócicas. Foi desenvolvido um processo de purificação da PspA4Pro cujas etapas iniciais foram: ruptura da biomassa celular, precipitação do homogenato obtido com o detergente brometo de cetiltrimetilamônio (CTAB) e remoção do precipitado por centrifugação. Foram avaliadas cromatografias de troca iônica (aniônica, catiônica), afinidade por metais, interação hidrofóbica e mista de troca catiônica e hidrofóbica. Utilizando precipitação com CTAB, cromatografia de troca aniônica, crioprecipitação em pH4,0 e cromatografia de troca catiônica atingiu-se a pureza requerida de PspA4Pro (>95%) com recuperação entre 14% e 33%. O processo alcançou níveis aceitáveis de endotoxina no produto final e a PspA4Pro purificada foi reconhecida por anticorpos anti-PspA4, manteve sua atividade e sua estrutura secundária. / Pneumococcal surface protein A (PspA) is found in all Streptococcus pneumoniae strains and is a promising candidate to be used in new pneumococcal vaccines. A purification process for PspA4Pro which inicial steps were: cell disruption, precipitation of the homogenate with the cationic detergent cetyltrimethylammonium bromide (CTAB) and pellet removal by centrifugation. The chromatographic techniques tested were ion exchange (anionic and cationic), immobilized metal affinity, hydrophobic interaction and mix mode with hydrophobic and cationic ligands. Using CTAB precipitation, anion exchange chromatography, crioprecipitation in pH4.0 and cation exchange chromatography the PspA reached the required purity (>95%) with recovery between 14% and 33% . The process reached acceptable levels of endotoxin in the final product and the purified PspA4Pro was recognized by anti-PspA4 antibodies and manteined its activity and secondary structure.

La transformation naturelle bactérienne permet aux micro-organismes d'échanger des informations génétiques pour promouvoir leurs réponses adaptatives pour faire face aux changements environnementaux. De l'ADN extracellulaire est incorporé et recombiné au génome de l'hôte. Ce processus augmente la plasticité des bactéries. Chez S. pneumoniae, un pathogène majeur chez l'Homme engendrant des infections pouvant être mortelles, la transformation bactérienne accentue la transmission de gènes de résistance aux antibiotiques. Chez les bactéries à Gram positif, l'opéron comF encode l'expression de deux protéines. L'une est démontrée comme étant essentielle à la transformation, est décrite pour être membranaire. La seconde n'a pas été étudiée. Cependant ces protéines n'ont pas été étudiées d'un point de vue structural ou fonctionnel. Des mutagenèse et le double hybride bactérien ont permis de mettre en évidence que ses protéines sont indispensables pour l'expression de la compétence et interagissent avec de nombreuses protéines du transformasome. De plus, l'expression des deux protéines de manière hétérologue prouve qu'elles sont solubles et forment des oligomères. L'analyse structurale de ComFA, atteste de la conformation atypique de cette helicase trimerique et hexamerique. En outre, l'activité ATPasique simple brin DNA-dépendant de cette protéine est démontrée. Finalement un complexe protéique a été révélé entre ComFA et ComFC dont l'étude microscopique à hautes résolutions prouve l'apparition d'un anneau via l'assemblage de deux hexamères. Ces résultats suggèrent que ComFA est le moteur tirant l'ADN dans la cellule. Quant à ComFC, elle semble aider à la stabilisation de ComFA. / Bacterial natural transformation allows microorganisms to exchange genetic information to promote their adaptive responses to cope with environmental changes. The extracellular DNA is incorporated and recombined with the genome of the host. This phenomenon increases the plasticity of Gram positive and negative bacteria. S. pneumoniae is a major pathogen for humans, which is causing infections that can be deadly. In this specie, bacterial transformation increases the transmission of antibiotic resistance.In Gram-positive bacteria, comF operon encodes the expression of two proteins. One of them, shown to be essential for natural transformation, is expected to be a membrane protein. The second is not described. However, up to now neither protein has been studied from a structural or functional point of view. Mutagenesis technique and double hybrid bacterial assay allowed to show that both proteins are essential for the expression of the competence and interact with many proteins of the transformasome. In addition, heterologous expresion of both proteins have shown their solubility and the formation of oligomers. Structural analysis of ComFA demonstrates the unique conformation of this hexameric and trimeric helicase. Furthermore, the ATPase single stranded DNA-dependent activity of this protein could be detected. Finally, a protein complex is formed between ComFA and ComF, and high-resolution microscopic study proves the occurrence of a ring via a two-hexamers. These results suggest that ComFA is the engine pulling the DNA in the cell. As for ComFC, this protein seems to help stabilizing of ComFA.

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.

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%).

<p><em>Streptococcus pneumoniae</em> (pneumokok) je&nbsp; jedan&nbsp; od&nbsp; vodećih&nbsp; uzroka morbiditeta i mortaliteta &scaron;irom sveta, kada su u pitanju infektivne bolesti. Pretežno izaziva infekcije gornjih respiratornih puteva (sinuzitis, otitis) i konjunktivitis. Vodeći je uzročnih vanbolničkih pneumonija, bakterijskog meningitisa i sepse. Lekovi izbora u terapiji pneumokoknih bolesti su beta laktamski antibiotici i makrolidi. Iako se makrolidni antibiotici uveliko koriste u lečenju pneumokoknih infekcija &scaron;irom sveta, porast rezistencije na makrolide&nbsp; bi&nbsp; mogao&nbsp; da&nbsp; kompromituje&nbsp; njihovu&nbsp; upotrebu. Rezistencija pneumokoka na makrolide je posredovana putem dva glavna mehanizma: modifikacija ciljnog mesta delovanja leka&nbsp; i aktivni efluks leka. Metilaciju 23S ribozomalne ribonukleinske kiseline (rRNK) obavlja enzim metilaza, čiju sintezu kodira<em> ermB</em> gen. Kod ovog tipa rezistencije dolazi do ukr&scaron;tene rezistencije na makrolide (M), linkozamide (L) i streptogramine B (Sb). Ovakav vid rezistencije se ispoljava kao MLS_b - fenotip i karakteri&scaron;e ga visok nivo rezistencije. Može se javiti kao konstitutivni (cMLS) i inducibilni (iMLS). Drugi mehanizam rezistencije na makrolide je aktivni efluks leka, kodiran od strane <em>mefA</em>&nbsp; gena. Efluks antibiotik a determini&scaron;e rezistenciju samo na 14-člane i 15-člane makrolide, bez ukr&scaron;tene rezistencije. Ispoljava se kao M-fenotip, a karakteri&scaron;e ga niži stepen rezistencije. Cilj ove studije je bio&nbsp; da&nbsp; se&nbsp; odredi u čestalost&nbsp; makrolidne&nbsp; rezistencije <em>Streptococcus pneumoniae</em> među invazivnim i neinvazivnim izolatima kod dece i odraslih, da se odrediti u čestalost korezistencije i multiple rezistencije kod makrolid rezistentnih sojeva&nbsp; <em>Streptococcus pneumoniae</em>, da se fenotipski odredi tip rezistencije na makrolide i da se ispita genska osnova makrolidne rezistencije (detektovati prisustvo <em>ermB</em> i <em>mefA</em> gena). Analizirani su podaci o 326 sojeva <em>Streptococcus pneumoniae</em> rezistentnih na makrolide (MRSP) sakupljenih &scaron;irom&nbsp; Srbije&nbsp; u&nbsp; periodu&nbsp; od&nbsp; januara&nbsp; 2010.&nbsp; do&nbsp; decembra&nbsp; 2012.&nbsp; godine. Sakupljeni&nbsp; MRSP&nbsp; izolati&nbsp; su&nbsp; transportovani&nbsp; u&nbsp; Nacionalnu&nbsp; referentnu laboratoriju za streptokok radi daljih ispitivanja. Identifikacija je vr&scaron;ena na osnovu mikroskopskih, kulturelnih i biohemijskih osobina. Konzervacija je vr&scaron;ena u moždano-srčanom bujonu sa 10% sadržajem glicerola na -80&deg;C. Dvostruki&nbsp; disk&nbsp; difuzioni&nbsp; test,&nbsp; kombinovani&nbsp; difuzion odilucioni&nbsp; test&nbsp; i automatizovani VITEK 2 sistem su kori&scaron;ćeni za određivanje fenotipova rezistencije na makrolide. Geni koji kodiraju rezistenciju na makrolide su detektovani PCR metodom. Ukupna rezistencija sojeva <em>S.pneumoniae</em> na makrolide u Srbiji je iznosila 34%. Sojevi <em>S.pneumoniae</em> rezistentni na makrolide su če&scaron;će bili izolovani kod dece (36%) u odnosu na odrasle (29%) osobe, i če&scaron;će su izolovani iz neinvazivnih (35,5%) u odnosu na invazivne (27,4%) materijale. Dominantan fenotip rezistencije na makrolide je bio MLS_b fenotip (78,5%). Konstitutivan MLS fenotip je bio zastupljen kod 73,9%, a inducibilan MLS kod 4,6% MRSP izolata. Potvrđena je udruženost <em>mefA</em>&nbsp; gena i M fenotipa; <em>ermB</em> gena i iMLS fenotipa, kao i <em>ermB</em> gena i cMLS fenotipa. Prisustvo oba ermB i mefA gena rezistencije je potvrđeno kod 43,9 % izolata. Svi izolati sa koji su imali oba gena rezistencije su ispoljili&nbsp; MLS_b fenotip.&nbsp; Istovremena&nbsp; neosetljivost&nbsp; na&nbsp; penicilin&nbsp; je bila zastupljena kod 16% MRSP sojeva. Visok nivo rezistencije na penicilin je imalo svega 5,8% MRSP izolata. Među MRSP sojevima je bio prisutan visok nivo&nbsp; rezistencije&nbsp; na&nbsp; tetraciklin&nbsp; (81,3%)&nbsp; i&nbsp; trimetoprim-sulfametoksazol (74,3%). Multirezistenti sojevi, koji su bili rezistentni na tetracikline i trimetoprim-sulfametoksazol su predstavljali dve trećine (66,1%) MRSP izolata.&nbsp; Zastupljenost&nbsp; udružene&nbsp; rezistencije&nbsp; MRSP&nbsp; na&nbsp; tetraciklin i trimetoprim-sulfametoksazol je bila veća kod sojeva sa MLS fenotipom (73,1%)&nbsp; u&nbsp; odnosu&nbsp; na&nbsp; sojeve&nbsp; sa&nbsp; M&nbsp; fenotipom&nbsp; (36,7%). Zastupljenost istovremene rezistencije na makrolide i druge antibiotike među kojima su penicilin, amoksicilin, cefotaksim, tetraciklin, trimetoprim-sulfametoksazol, kao&nbsp; i&nbsp; multirezistentnih&nbsp; sojeva&nbsp; je&nbsp; bila&nbsp; veća&nbsp; kod pedijatrijskih&nbsp; izolata pneumokoka&nbsp; u&nbsp; odnosu&nbsp; na&nbsp; sojeve&nbsp; dobijene&nbsp; kod&nbsp; odraslih.&nbsp; U čestalost istovremene rezistencije na makrolide i druge antibiotike među kojima su tetraciklin i ofloksacin je bila vi&scaron;e prisutna među neinvazivnim u odnosu na invazivne MRSP izolate. Invazivni MRSP izolati iz likvora su pokazivali veću rezistenciju na beta laktamske antibiotike u odnosu neinvazivne sojeve. MRSP sojevi su pokazali veoma visok nivo osetljivosti na levofloksacin (99,6), telitromicin (98,4%), cefotaksim (93,5%), i mipenem (97,3%). MRSP sojevi su u potpunosti bili osetljivi na vankomicin, linezolid, moksifloksacin, sparfloksacin, rifampicin&nbsp; i&nbsp; pristinamicin.&nbsp; Među&nbsp; invazivnim&nbsp; sojevima <em>S.pneumoniae</em> rezistentnim na makrolide je nađeno 12 različitih serotipova. Polovina izolata je pripadala serotipovima 19F (25%) i 14 (23%), dok su sledeći po učestalosti bili 6A (10,4%) i 23F (8,3%). Istovremena rezistencija na makrolide, penicilin, tetracikline i trimetoprim-sulfametoksazol je nađena kod serotipova 19F, 14 i 23F, dok su serotpovi 12F i 31 bili neosetljivi samo na makrolide. Na&scaron;e istraživanje predstavlja prvu detaljnu analizu fenotipskih i&nbsp; genotipskih&nbsp; osobina&nbsp; sojeva&nbsp; pneumokoka&nbsp; rezistentnih&nbsp; na&nbsp; makrolidne antibiotike u Srbiji. Dobijeni rezultati ukazuju na&nbsp; potrebu za aktivnim nadzorom nad pneumokoknim infekcijama u Srbiji.</p> / <p><em>Streptococcus pneumoniae</em> (pneumococcus) is one of the leading morbidity and&nbsp; mortality&nbsp; causes&nbsp; all&nbsp; over&nbsp; the&nbsp; world&nbsp; with&nbsp; respect&nbsp; to&nbsp; infectious&nbsp; diseases. <em>Streptococcus&nbsp; pneumoniae</em> is&nbsp; a&nbsp; leading&nbsp; cause&nbsp; of upper&nbsp; respiratory&nbsp; tract infections&nbsp; (&nbsp; sinusitis,&nbsp; otitis)&nbsp; and&nbsp; conjunctivitis. It&nbsp; is&nbsp; also&nbsp; the&nbsp; most&nbsp; common cause&nbsp; of&nbsp; community-acquired&nbsp; pneumonia, bacterial&nbsp; meningitis&nbsp; and&nbsp; sepsis. Beta lactam and&nbsp; macrolide antibiotics remained a first choice for empirical treatment of pneumococcal infections. Although macrolides are widely used for&nbsp;&nbsp; treatment&nbsp;&nbsp; of&nbsp;&nbsp; pneumococcal&nbsp;&nbsp; infections, an&nbsp;&nbsp; increase&nbsp;&nbsp; in&nbsp;&nbsp; macrolide resistance&nbsp; might compromise&nbsp; their use. Pneumococcal&nbsp; macrolide resistance is&nbsp; mediated&nbsp; by&nbsp; two&nbsp; major&nbsp; mechanisms:&nbsp; target&nbsp; site&nbsp; modification&nbsp; and&nbsp; active drug&nbsp; efflux.&nbsp; Methylation&nbsp; of&nbsp; the&nbsp; 23S&nbsp; ribosomal&nbsp; ribonucleic&nbsp; acid&nbsp; (rRNA)&nbsp; is performed&nbsp;&nbsp; by&nbsp;&nbsp; the&nbsp;&nbsp; enzyme&nbsp;&nbsp; methylase,&nbsp;&nbsp; encoded&nbsp;&nbsp; by&nbsp;&nbsp; the<em> ermB </em>gene. Modification&nbsp; of&nbsp; ribosomal&nbsp; targets&nbsp; leads&nbsp; to&nbsp; cross-resistance to&nbsp; macrolides (M),&nbsp; lincosamides&nbsp; (L)&nbsp; and&nbsp; streptogramins&nbsp; B&nbsp; (Sb). It&nbsp; is&nbsp; expressed&nbsp; as&nbsp; the MLS_b &ndash;phenotype,&nbsp; which&nbsp; confers&nbsp; a&nbsp; high-level&nbsp; resistance. This&nbsp; phenotype&nbsp; can&nbsp;&nbsp; be&nbsp;&nbsp; either&nbsp;&nbsp; constitutively&nbsp;&nbsp; (cMLS)&nbsp;&nbsp; or&nbsp;&nbsp; inducibly&nbsp;&nbsp; (iMLS). expressed. Another macrolide resistance mechanism is the active drug efflux, encoded by&nbsp; the <em>mefA&nbsp;</em> gene.&nbsp; The&nbsp; drug&nbsp; efflux&nbsp; confers&nbsp; resistance&nbsp; to&nbsp; 14-&nbsp; and&nbsp; 15-membered&nbsp; macrolides&nbsp; only,&nbsp; with&nbsp; no&nbsp; cross-resistance.&nbsp; It&nbsp; is&nbsp; expressed&nbsp; as&nbsp; the M-phenotype,&nbsp; which&nbsp; confers&nbsp; low-level&nbsp; resistance.&nbsp; The&nbsp; objective of&nbsp; this study&nbsp;&nbsp; was&nbsp;&nbsp; :&nbsp;&nbsp; 1) to&nbsp;&nbsp; examine&nbsp;&nbsp; the&nbsp;&nbsp; prevalence of&nbsp;&nbsp; macrolide&nbsp;&nbsp; resistant <em>Streptococcus&nbsp;&nbsp; pneumoniae </em>(MRSP) among&nbsp;&nbsp; invasive&nbsp;&nbsp; and&nbsp;&nbsp; noninvasive isolates in children and adults, 2) to examine the prevalence of coresistance and multiple-resistance among MRSP strains, 3) to examine the prevalence of&nbsp; macrolide&nbsp; resistant&nbsp; phenotypes,&nbsp; and&nbsp; 4)&nbsp; to&nbsp; examine&nbsp; the&nbsp; prevalence&nbsp; of macrolide&nbsp; resistant&nbsp; genotypes&nbsp; (detect&nbsp; the&nbsp; presence of&nbsp; the <em>ermB</em>&nbsp;&nbsp; and <em>mefA</em> gene).&nbsp; A&nbsp; total&nbsp; of&nbsp;&nbsp; 326&nbsp; MRSP&nbsp; strains&nbsp; were&nbsp; analyzed,&nbsp; which&nbsp; were&nbsp; collecte dall&nbsp; over&nbsp; Serbia&nbsp; in&nbsp; the&nbsp; period&nbsp; from&nbsp; January,&nbsp; 2010&nbsp; - December,&nbsp; 2012.&nbsp; The collected&nbsp;&nbsp; MRSP&nbsp;&nbsp; isolates&nbsp;&nbsp; were&nbsp;&nbsp; referred&nbsp;&nbsp; to&nbsp;&nbsp; the&nbsp;&nbsp; National&nbsp; Reference Laboratory&nbsp; for&nbsp; streptococci&nbsp; and&nbsp; pneumococci for&nbsp; further&nbsp; investigation. Identification based on microscopic, culture and biochemical features of the isolates. Conservation was performed in the brain-heart infusion broth with a&nbsp; 10%&nbsp; glycerol&nbsp; content&nbsp; at&nbsp; -80&deg;C.&nbsp; Macrolide&nbsp; resistance&nbsp; phenotypes&nbsp; were determined by a double disc diffusion test, combine d diffusion-dilution test and&nbsp;&nbsp; automatized&nbsp;&nbsp; VITEK&nbsp; 2 system. Macrolide&nbsp;&nbsp; resistance&nbsp;&nbsp; genes&nbsp;&nbsp; were&nbsp; determined by PCR. Overall, macrolide nonsusceptibility rate in Serbia was 34%.&nbsp; MRSP&nbsp; isolates&nbsp; were&nbsp; more&nbsp; prevale nt&nbsp; among&nbsp; children&nbsp; (36%)&nbsp; than adults&nbsp; (29%),&nbsp; and&nbsp; were&nbsp; more&nbsp; prevalent&nbsp; among&nbsp;&nbsp; noninvasive&nbsp; (35.5%)&nbsp; than invasive&nbsp; (27.4%)&nbsp; samples.&nbsp; Predominant&nbsp; macrolide&nbsp; resistance&nbsp; phenotype was&nbsp; the&nbsp; MLS b&nbsp; phenotype&nbsp; (78.5%),&nbsp; from&nbsp; which&nbsp; 73.9 %&nbsp; belonged&nbsp; to&nbsp; cMLS and&nbsp; 4.6%&nbsp; to&nbsp; iMLS&nbsp; phenotype.&nbsp; All&nbsp; the&nbsp; strains&nbsp; assigne d&nbsp; to&nbsp; the&nbsp; MLS_b phenotype harbored<em> ermB</em> gene, while all the strains with M phenotype had the mefA gene.&nbsp; The&nbsp; presence&nbsp; of&nbsp; both ermB and mefA resistance&nbsp; genes&nbsp; was confirmed&nbsp; in&nbsp; 43.9&nbsp; %&nbsp; of&nbsp; isolates. All&nbsp; the&nbsp; isolates&nbsp; which&nbsp; harbored&nbsp; both resistance genes expressed the MLS_b phenotype. Among macrolide resistant strains,&nbsp; penicillin&nbsp; nonsusceptiblility&nbsp; was&nbsp; observed&nbsp;&nbsp; in&nbsp; 16% .&nbsp; A&nbsp; high&nbsp; level resistance was confirmed in 5. 8% of MRSP isolates. MRSP strains showed high&nbsp; resistance rates to tetracyclin&nbsp; (81.3%) and&nbsp; trimethoprim-sulfamethoxazole&nbsp; (74.3%).&nbsp; Multiresistant&nbsp; strains,&nbsp; resistant&nbsp; to&nbsp; tetracyclines and&nbsp; trimethoprim-sulfamethoxazole,&nbsp; made&nbsp; two&nbsp; thirds&nbsp; (66.1&nbsp; %)&nbsp; of&nbsp; MRSP isolates.&nbsp; Among&nbsp; MRSP,&nbsp; co-resistance&nbsp; to&nbsp; tetracycline&nbsp; and&nbsp; trimethoprim-sulfamethoxazole&nbsp; was&nbsp; more&nbsp; prevalent&nbsp; among&nbsp; MLS&nbsp; phenotypes&nbsp; (73.1%) than&nbsp; M&nbsp; phenotypes&nbsp; (36.7%).&nbsp; Co-resistance&nbsp; strains&nbsp; to&nbsp; macrolides&nbsp; and&nbsp; other antibiotics including&nbsp;&nbsp;&nbsp; penicillin,&nbsp;&nbsp; amoxicillin,&nbsp;&nbsp;&nbsp; cefotaxime,&nbsp; tetracyclin, trimethoprim-sulfamethoxazole and multiresistant&nbsp; strains&nbsp; were more prevalent among children than adult. Coresistance to macrolides and other antibiotics&nbsp; including&nbsp; tetracycline&nbsp; and&nbsp; ofloxacin&nbsp; was&nbsp; more&nbsp; prevalent&nbsp; among noninvasive&nbsp;&nbsp; than&nbsp;&nbsp; invasive&nbsp;&nbsp; strains.&nbsp;&nbsp; Invasive&nbsp;&nbsp; MRSP&nbsp;&nbsp; isolates&nbsp;&nbsp; from&nbsp;&nbsp; the cerebrospinal fluid showed a higher resistance rate to beta lactam antibiotics than&nbsp; noninvasive&nbsp; strains.&nbsp; MRSP&nbsp; strains&nbsp; had&nbsp; a&nbsp; high&nbsp; susceptibility&nbsp; rates&nbsp; to levofloxacin&nbsp;&nbsp; (99.6),&nbsp;&nbsp; telithromycin&nbsp;&nbsp; (98.4%),&nbsp;&nbsp; cefotak sime&nbsp;&nbsp; (93.5%)&nbsp;&nbsp; and imipenem&nbsp; (97.3%).&nbsp; MRSP&nbsp; strains&nbsp; were&nbsp; fully&nbsp; susceptible&nbsp; to&nbsp; vancomycin, linezolid, moxifloxacin, sparfloxacin, rifampicin a nd pristinamycin. Among macrolide&nbsp;&nbsp; resistant <em>S.pneumoniae</em> strains,&nbsp;&nbsp; 12 different&nbsp;&nbsp; serotypes&nbsp;&nbsp; were identified.&nbsp; One&nbsp; half&nbsp; of&nbsp; these&nbsp; isolates&nbsp; belonged&nbsp; to the&nbsp; 19F&nbsp; (27.1%)&nbsp; and&nbsp; 14 (22.&nbsp; 9%)&nbsp; serotype,&nbsp; followed&nbsp; in&nbsp; frequency&nbsp; by&nbsp; the&nbsp; 6A&nbsp; (10.41%)&nbsp; and&nbsp; 23F (8.3%)&nbsp; serotype .&nbsp; Multiresistant&nbsp; strains&nbsp; (macrolides,&nbsp; penicillin,&nbsp; tetracyclines and&nbsp; trimethoprim-sulfamethoxazole)&nbsp; belonged&nbsp; to&nbsp; serotypes 19F,&nbsp; 14&nbsp; and 23F, while the 12F and 31 serotype were resistant to macrolides only. This in vestigation&nbsp;&nbsp; represents&nbsp;&nbsp; the&nbsp;&nbsp; first&nbsp;&nbsp; detailed&nbsp;&nbsp; analysis of&nbsp;&nbsp; phenotypes&nbsp;&nbsp; and genotypes&nbsp; of&nbsp; macrolide&nbsp; resistant&nbsp; pneumococcal&nbsp; strains&nbsp; in&nbsp; Serbia.&nbsp; The obtained&nbsp; results suggest&nbsp; the need for an active surveillance&nbsp; of pneumococcal infections in Serbia.</p>