Obtención de sobrenadante de cultivo aglutinador de hematíes portadores del antígeno de grupo sanguíneo B / Obtention of cell culture supernatant for erythrocyte agglutination of blood group B antigen

Introducción: la obtención de anticuerpos monoclonales en líquido ascítico ha ido decayendo paulatinamente por la aparición de alternativas de producción in Vitro, que permiten alcanzar mayores volúmenes y un control más riguroso del proceso productivo, lo que incrementa la reproducibilidad de procesos y la calidad de los productos. Objetivo: evaluar dos métodos de producción de sobrenadante de cultivo rico en una inmunoglobulina de ratón del tipo IgG2b, aglutinadora de hematíes humanos portadores del antígeno del grupo sanguíneo B, según el sistema ABO; la cual es secretada por el hibridoma C6G4. Métodos: se evaluaron dos métodos de producción del anticuerpo con el empleo de un biorreactor CELLine, útil como modelo para la obtención de anticuerpos monoclonales en cultivos de alta densidad celular. Los métodos se diferenciaron esencialmente en la densidad celular de siembra en el biorreactor y en la duración del periodo de fermentación entre la siembra y la cosecha del caldo de cultivo rico en anticuerpos. Para cada método se determinó la concentración específica de anticuerpos y la potencia de aglutinación del sobrenadante, así como la densidad y la viabilidad celular del cultivo alcanzadas en el momento de la cosecha. Resultados: se observó que ambos métodos generaron sobrenadantes de cultivo con una potencia de aglutinación similar, a pesar de que se encontraron diferencias en el resto de las variables medidas. Si bien uno de los métodos produjo una mayor concentración de anticuerpos en el sobrenadante, no se observaron diferencias en la potencia de aglutinación de los sobrenadantes obtenidos por ambas alternativas. Conclusiones: los dos métodos estudiados permitieron obtener volúmenes semejantes de sobrenadante anti-B con diferentes concentraciones de anticuerpos, pero con una potencia de aglutinación similar. La principal diferencia residió en que uno de los métodos permitió obtener el mismo volumen del producto en un tiempo sensiblemente menor...

Introduction : the obtention of monoclonal antibodies in ascite fluid has been declining gradually due to the appearance of alternative in vitro production that achieve higher volumes and a more precise monitoring of the production process, which increases the reproducibility of processes and the quality of products. Objective : to evaluate two methods to make cell culture supernatant rich in murine monoclonal IgG2b type, with agglutinating activity against human red cell of blood group antigen B (ABO system), which is secreted by murine hybridoma C6G4. Methods : two methods were evaluated for antibody production in cell culture supernatant using as model a CELLine bioreactor for the production of monoclonal antibodies in high cell density culture. Both methods essentially differed in the seeding cell density in the bioreactor and the fermentation period between seeding and harvesting of the culture broth rich in antibodies. The specific antibody concentration and potency of agglutination was determined in the obtained supernatant and also the cell density and cell viability of the culture reached at the time of harvest. Results : both methods generated culture supernatants with similar agglutination strength despite differences found in the rest of the variables measured. Even when one of the methods produced a higher antibody concentration in the supernatants, no differences in potency of the supernatants agglutination obtained by both alternatives were observed. Conclusions : both methods generated supernatant anti-B with different concentrations of antibodies but similar potency of agglutination. The main difference was that with one of the methods the same volume of the product was obtained in a considerably minor time...

Obtención de anticuerpos monoclonales de ratón contra proteasa de cisteína 5 recombinante de Entamoeba histolytica / Production of monoclonal antibodies against cysteine protease 5 of Entamoeba histolytica

Objetivo. Obtener anticuerpos monoclonales de ratón contra la proteasas de cisteína 5 (EhCP5) de Entamoeba histolytica. Materiales y métodos. Se inmunizaron ratones BALB/c por vía intraperitoneal con adyuvante de Freund completo e incompleto con la proteína recombinante EhCP5 obtenida a partir del cultivo de E.coli DH5α trasfectada con el vector recombinante pJC45 que expresa dicha proteína. Se seleccionó el animal con mejor respuesta de anticuerpos. Al cual se le extrajo su bazo como fuente de linfocitos B, los cuales se fusionaron utilizando PEG con células de mieloma de ratón SP2-0/Ag14. Se procedió a selección de los hibridomas y a la evaluación de los sobrenadantes de las colonias que crecieron a los 7 días mediante ELISA. Los hibridomas con valores más altos de anticuerpos específicos contra la proteína EhCP5r se seleccionaron, y los clones obtenidos por diluciones limitantes fueron expandidos. Resultados. A partir de un clon secretor estable se purifico el anticuerpo monoclonal anti EhCP5r del isotipo IgG1 por cromatografía de afinidad con proteína G. Los clones fueron expandidos in vivo ein vitro. Con el anticuerpo purificado se diseñaron tres sistemas de captura para evaluar la aplicabilidad del anticuerpo monoclonal anti EhCP5r como método inmunodiagnóstico. Conclusiones. Se logro la producción de un anticuerpo monoclonal específico contra EhCP5r que permite diferenciar Entamoeba histolytica de Entamoeba dispar.

Objective. Obtain mouse monoclonal antibodies against cysteine proteases 5 (EhCP5) of Entamoeba histolytica. Materials and methods. BALB/c mice were immunized intraperitoneally with complete and incomplete Freund adjuvant EhCP5 with the recombinant EhCP5 protein obtained from E.coli DH5α culture transfected with the recombinant vector pJC45 that expresses said protein. The animal with the best antibody response was selected. Its spleen was extracted as a source of B-lymphocytes, which were merged using PEG miceSP2-0/Ag14 myeloma cells. The team proceeded to undergo the selection of the hybridomas and the evaluation of the supernatants of the colonies that grew after 7 days by ELISA. The hybridomas with higher values of specific antibodies against the protein EhCP5r were selected, and clones obtained by limiting dilution were expanded Results. With the use of a stable secreting clone the monoclonal antibody anti EhCP5r IgG1 isotype was purified by affinity chromatography with protein G. The clones were expanded in vivo and in vitro. Three capture systems were designed with the purified antibody to assess the applicability of the monoclonal antibody anti EhCP5r as an immunodiagnostic method. Conclusions. The production of a specific monoclonal antibody against EhCP5r was achieved to differentiate Entamoeba histolytica from Entamoeba dispar.

Drugs obtained by biotechnology processing / Drogas obtidas pelo processamento biotecnológico

In recent years, the number of drugs of biotechnological origin available for many different diseases has increased exponentially, including different types of cancer, diabetes mellitus, infectious diseases (e.g. AIDS Virus / HIV) as well as cardiovascular, neurological, respiratory, and autoimmune diseases, among others. The pharmaceutical industry has used different technologies to obtain new and promising active ingredients, as exemplified by the fermentation technique, recombinant DNA technique and the hybridoma technique. The expiry of the patents of the first drugs of biotechnological origin and the consequent emergence of biosimilar products, have posed various questions to health authorities worldwide regarding the definition, framework, and requirements for authorization to market such products.

Nos últimos anos, tem aumentado exponencialmente o número de fármacos de origem biotecnológica ao dispor das mais diversas patologias, entre elas destacam-se, os diferentes tipos de cancêr, as doenças infecciosas (ex. vírus AIDS/HIV), as doenças autoimunes, as doenças cardiovasculares, a Diabetes Mellitus, as doenças neurológicas, as doenças respiratórias, entre outras. A indústria farmacêutica tem recorrido a diferentes tecnologias para a obtenção de novos e promissores princípios ativos, como são exemplo a fermentação, a técnica de DNA Recombinante, a técnica de hidridoma, entre outras. A queda das patentes dos primeiros fármacos de origem biotecnológica e o consequente aparecimento dos produtos biossimilares têm colocado diferentes questões às autoridades de saúde mundiais, sobre a definição, enquadramento e exigências para a autorização de entrada no mercado deste tipo de produtos.

Desenvolvimento de técnicas de imunoensaio para detecção de microcistina em amostras ambientais / Development of immunoassay techniques to detect microcystin in environmental samples

A contaminação da água para consumo humano por toxinas produzidas por cianobactérias é um problema de saúde pública e das autoridades em todo o mundo. Microcistina-LR (MCLR) é uma cianotoxina heptapeptídica cíclica que inibe as proteínas fosfatases PP1 E PP2A nos hepatócitos. Microcistinas são produzidas por diversos gêneros de cianobactérias e mais de 70 variações estruturais têm sido caracterizadas em florações naturais. Por serem haptenos, as microcistinas são incapazes de induzir uma resposta imune em animais. Conseqüentemente, foi necessário aplicar métodos de conjugação envolvendo a adição de uma proteína carreadora, mcKLH (cationized Keyhole Limpet Hemocyanin). Portanto, o objetivo inicial desta tese foi o de obter anticorpos monoclonal (em camundongos) e policlonal (em coelho) anti- MCLR. Com relação ao anticorpo monoclonal foram obtidos 9 hibridomas (k₂9, k₂10, k₃17, k₂48, k₂84, k₂90, k₂161, k₂226, k₂232), sendo que apenas 5 se mostraram estáveis (k₂9, k₃17, k₂48, k₂84, k₂232). Estes foram selecionados para serem isotipados, expandidos em líquido ascítico, purificados em coluna cromatográfica de proteína-A e titulados. Dentre estes cinco hibridomas secretores de anticorpos, o clone k₃17 foi o que melhor reconheceu (mais específico) a toxina MCLR. Os anticorpos do sobrenadante de meio de cultura do hibridoma e o fluido ascítico purificado foram identificados pelo ensaio ELISA (Enzyme Linked Immunosorbent Assay) previamente padronizado. Mesmo sensibilizando a placa de ELISA com diferentes antígenos, tais como MCLR-cBSA, MCLR, MCLR, MCRR, MCYR e MCLA, o clone 17 foi o que apresentou melhor linearidade frente às variantes de microcistina. Portanto, o clone 17 (isótipo IgG1) obtido é muito promissor e será usado para detecção de MCLR na água para consumo humano através do...

The contamination of drinking water by cyanobacterial toxins is a public health issue and a concern for water authorities throughout the world. Microcystin-LR (MCLR) is a hazardous cyclic heptapeptide cyanotoxin, which inhibits protein phosphatase PP1 and PP2A in hepatocytes. Microcystins are produced by several genera of cyanobacteria and presents more than 70 structural variations characterized in natural blooms. As haptens, microcystins are unable to invoke an immune response in animals. Consequently, the application of conjugation methods with an additional carrier protein, the KLH (Keyhole Limpet Hemocyanin) was necessary. The main objective of this study was to obtain monoclonal (in mice) and polyclonal (in rabbits) antibodies for reacting against MCLR. In what refers to monoclonal antibodies, 9 hybridomas (k₂9, k₂10, k₃17, k₂48, k₂84, k₂90, k₂161, k₂226, k₂232) were obtained; however only 5 were stables (k₂9, k₃17, k₂48, k₂84, k₂232). These were selected to be isotyped, expanded in ascitic fluid, purified by protein-A column chromatography and then, they were titrated. Out of these five antibody-secretor hybridomas, clone k₃17 was the best to recognize (more specific) the MCLR toxins. Antibodies in hybridoma cell culture supernatant and purified ascites fluid were identified by ELISA assay (Enzyme Linked Immunosorbent Assay) as prior standardized. Even when sensitizing ELISA plate with different antigens, as MCLR-cBSA, MCLR, MCLR, MCRR, MCYR and MCLA, clone 17 presented the best linearity against microcystin variants. Therefore, the obtained clone 17 (isotype IgG1) is a promising clone and shall be used for detecting MCLR in drinking water through the development of a competitive ELISA immunoassay kit. In what refers to the polyclonal antibody, MCLR-mcKLH was used as...