Optimization of production process of Aeromonas veronii CA07 strain inactivated vaccine / 中国生物制品学杂志

@#Abstract：Objective To optimize the production process of inactivated vaccine of Aeromonas veronii（AV）CA07 strain. Methods The fermentation culture process of AV CA07 strain liquid was determined through the optimization of the culture time（2～16 h），medium（optimized fermentation medium，LB medium and NB medium）and fermentation conditions（in⁃ oculation amount of 1%，5%，10% and 15%；ventilation rate of 2，4，6 and 8 L／min and fermentation time of 6，8，10 and 12 h）. The optimal inactivation process was determined through the comparison of the final concentration of formalde⁃ hyde solution（0. 10%，0. 20%，0. 30% and 0. 40%），inactivation temperature（28 and 37 ℃）and inactivation time（24， 48 and 72 h）. The large⁃scale production process of inactivated vaccine of AV CA07 strain in 500 L fermentor was estab⁃ lished and the prepared vaccines were tested for safety and immunogenicity. Results The optimal inoculation amount of AV CA07 strain was 5%，ventilation rate was 4 L／min and culture time was 10 ~ 12 h. The optimal inactivation condition was adding formaldehyde solution with final concentration of 0. 30% incubating at 37 ℃ for 24 h. The number of viable bacteria in the fermentation broth of AV CA07 strain prepared in 500 L fermentor was more than 8 × 109 CFU／mL. All crucian carps immunized with the inactivated vaccine by abdomen survived. After challenge，the relative immune protection rate was more than 90%. Conclusion AV CA07 strain inactivated vaccine prepared by optimized production process showed good safety and immunogenicity.

Diseño de un programa de análisis de peligros y puntos críticos control (HACCP) para la producción de toxoide tetánico / Design of a program of hazard analysis and critical control point (HACCP) for production of Tetanus Toxoid

El toxoide tetánico es una neurotoxina modificada que induce la formación de una antitoxina protectora contra la enfermedad denominada tétanos. Este antígeno es obtenido a partir de procesos fermentativos con la bacteria anaerobia Clostridium tetani y es utilizado para la formulación de vacunas simples y combinadas inactivadas. Con el propósito de atender a las recomendaciones y regulaciones de la Organización Mundial de la Salud (OMS), el objetivo de este trabajo fue diseñar un Programa de Análisis de Peligros y Puntos Críticos de Control (HACCP) en la producción del antígeno Toxoide Tetánico, desde la recepción de la cepa certificada en el área de producción hasta el almacenamiento del toxoide tetánico purificado. Para ello, inicialmente se evaluó el cumplimiento de los prerequisitos (BPM, POES, BPL). Posteriormente, se procedió al diseño del plan HACCP mediante la ejecución de las 5 tareas preliminares y la aplicación de los 7 principios, conforme a la metodología descrita por la OMS. A partir del análisis de peligros en todas las etapas del proceso de producción del toxoide tetánico se identificaron 3 puntos críticos de control: detoxificación, filtración estéril final y almacenamiento de toxoide tetánico purificado. Se establecieron los límites críticos, los procedimientos de vigilancia, las acciones correctivas, los procedimientos de verificación y de documentación. La propuesta tiene como fin garantizar la calidad e inocuidad del producto elaborado, la protección del personal involucrado en el proceso y del medio ambiente con miras a la obtención de la certificación como laboratorio productor de vacunas

Tetanus toxoid is a modified neurotoxin that induces the formation of protective antitoxin of the disease called tetanus. This antigen is obtained from fermentation processes with anaerobic bacteria Clostridium tetani and it is used to formulate simple and combined inactivated vaccines. In order to meet the recommendations and regulations of World Health Organization (WHO), the aim of this work was to design a Program of Hazard Analysis and Critical Control Points (HACCP) in the production of antigen Tetanus Toxoid, starting from the receipt of the certified strain in the production area through the storage of purified tetanus toxoid. For this, initially fulfilling the prerequisites (GMP, SSOP and GLP) was evaluated. Subsequently, we proceeded to design HACCP plan by running 5 preliminary tasks and application of the 7 principles, according to the methodology described by WHO. From the hazard analysis at all stages of the production process of tetanus toxoid three critical control points were identified: detoxification, final sterile filtration and storage of purified tetanus toxoid. Critical limits, monitoring procedures, corrective actions, verification and documentation procedures were established. The proposal aims to assure the quality and safety of the final product, the protection of personnel involved in the process and the environment, with a view to obtaining certification as a vaccine production laboratory

Yellow fever outbreak in Brazil: the puzzle of rapid viral spread and challenges for immunisation

We discuss the complex eco-social factors involved in the puzzle of the unexpected rapid viral spread in the ongoing Brazilian yellow fever (YF) outbreak, which has increased the reurbanisation risk of a disease without urban cases in Brazil since 1942. Indeed, this rapid spatial viral dissemination to the Southeast and South regions, now circulating in the Atlantic Forest fragments close to peri-urban areas of the main Brazilian megalopolises (São Paulo and Rio de Janeiro) has led to an exponential increase in the number of yellow fever cases. In less than 18 months, 1,833 confirmed cases and 578 deaths were recorded most of them reported in the Southeast region (99,9%). Large epizooties in monkeys and other non-human primates (NHPs) were communicated in the country with 732 YF virus (YFV) laboratory confirmed events only in the 2017/2018 monitoring period. We also discuss the peculiarities and similarities of the current outbreak when compared with previous great epidemics, examining several hypotheses to explain the recent unexpected acceleration of epizootic waves in the sylvatic cycle of the YFV together with the role of human, NHPs and mosquito mobility with respect to viral spread. We conclude that the most feasible hypothesis to explain this rapidity would be related to human behavior combined with ecological changes that promoted a significant increase in mosquito and NHP densities and their contacts with humans. We emphasize the urgent need for an adequate response to this outbreak such as extending immunisation coverage to the whole Brazilian population and developing novel strategies for immunisation of NHPs confined in selected reserve areas and zoos. Finally, we stress the urgent need to improve the quality of response in order to prevent future outbreaks and a catastrophic reurbanisation of the disease in Brazil and other South American countries. Continuous monitoring of YFV receptivity and vulnerability conditions with effective control of the urban vector Aedes aegypti and significant investments in YF vaccine production capacity and research and development for reduction of adverse effects are of the highest priority.

Epidemiology of severe fever and thrombocytopenia syndrome virus infection and the need for therapeutics for the prevention

Over the past ten years there has been a marked increase in cases of severe fever and thrombocytopenia syndrome in East Asia. This tick-borne hemorrhagic fever presents along with clinical signs including high fever and leukopenia. In addition to humans, the virus has also been detected with shared genetic homology in farm animals including goats, cattle, horses, and pigs. Furthermore, several genotypes of severe fever and thrombocytopenia syndrome virus (SFTSV) are currently co-circulating between humans and animals. In China, where the virus was first detected in rural areas in 2009, the SFTSV mortality rate has been reported to be as 6% and higher than 30%, especially in immuno-compromised patients. Moreover, this virus has been isolated in neighbor countries including Japan and South Korea where the fatality rates in 2015 were more than 30% in both countries. In this review, we comprehensively summarize the virology, genotypes, pathogenesis, and epidemiology of SFTSV infection in humans and animals. Currently, a collaborative global approach against SFTSV infection is being undertaken; however, the need for continuous disease surveillance and production of an effective vaccine is imperative as this virus may lead to an epidemic of irreversible status in both humans and animals.

Strategies for producing high-yield viral vaccine antigens / 生物工程学报

Vaccination is an important strategy to prevent infectious diseases. However, low antigen yield of vaccine producing strains may lead to high cost of vaccines, low antigen production and vaccine failure. In recent years, many efforts have been made to improve the antigen yield of many vaccines. This mini-review summarizes various methods for increasing the antigen yield for vaccine production, including genetic modification of viruses, improvement of the adaptation of viruses to cells, and optimization of antigen expression systems and manufacturing procedures. Furthermore, we discuss the advantages and the problems of current strategies, as well as indicate the perspectives.

Evaluación de la carga microbiológica ambiental en áreas destinadas a producción y control de vacunas / Evaluation of the environmental microbiological burden in vaccine production and control areas

Objetivo: el objetivo del presente trabajo fue contribuir al aseguramiento de la calidad microbiológica de una planta de producción de vacunas, a través de la identificación de la carga microbiológica ambiental y su comportamiento frente a los desinfectantes utilizados de rutina. Método: Se estudió la flora residente de cada área clasificada. Se analizaron muestras de aire tomadas por los métodos volumétricos y sedimentación en placa. Las superficies y vestimenta del personal fueron evaluadas por el método de contacto. Se realizaron identificaciones en género y especie estableciéndose para cada área un Grupo de Microorganismos Indicador formado por microorganismos aislados con una frecuencia superior al 5 por ciento. Resultados: Bioterio: Staphylococcus spp (50 por ciento), Aerococcus spp (21 por ciento), Micrococcus spp (10 por ciento),Bacillus spp y Géneros Relacionados (6 por ciento); Cultivos Celulares Normales: Staphylococcus spp (48 por ciento), Micrococcus spp (34 por ciento),Bacillus spp y Géneros Relacionados (13 por ciento); Control de Calidad: Staphylococcus spp (50 por ciento), Micrococcus spp (27 por ciento), Kocuria spp (9 por ciento), Bacillus spp y Géneros Relacionados (7 por ciento); Producción: Staphylococcus spp (50 por ciento), Micrococcus spp (17 por ciento), Kocuria spp (11 por ciento), Leuconostoc spp (8 por ciento), Bacillus spp y Géneros Relacionados (6 por ciento). El grupo indicador para la Unidad de Producción se identificó como Staphylococcus spp (49,5 por ciento), Micrococcus spp. (23,0 por ciento), Bacillus spp y Géneros Relacionados (8,1 por ciento). El desafío de los desinfectantes en uso con cepas del grupo de microorganismos indicadores evidenció en general una acción microbicida alta. Conclusión: los resultados proporcionan información sobre la carga microbiológica del ambiente que será de utilidad tanto para la comprensión del ingreso y circulación de microorganismos como para la implementación de medidas para prevenir la contaminación microbiana, aspectos críticos en la fabricación de vacunas seguras, puras y eficaces(AU)

Objectives: the objective of this study was to support microbiological quality assurance in a vaccine production plant through identification of environmental microbiological charge and its behavior with routine disinfectants. Methods: the existing flora of each classified area was studied. Air samples taken by volumetric and plate sedimentation methods were analyzed. Surfaces and the gown of the staff were assessed by contact method. Genera and species were identified, thus setting a Group of Indicator Microorganisms made up of microorganisms that were isolated at a rate greater than 5 percent for each facility. Results: animal Facility: Staphylococcus spp (50 percent), Aerococcus spp (21 percent), Micrococcus spp (10 percent), Bacillus spp and related genera (6 percent); Normal Tissue Culture Laboratory: Staphylococcus spp (48 percent), Micrococcus spp (34 percent), Bacillus spp and related genera (13 percent); Quality Control Laboratory: Staphylococcus spp (50 %), Micrococcus spp (27 percent), Kocuria spp (9 percent), Bacillus spp and related genera (7 percent); Production: Staphylococcus spp (50 percent), Micrococcus spp (17 percent), Kocuria spp (11 percent), Leuconostoc spp (8 percent), Bacillus spp and related genera (6 percent). The Group of Indicator Microorganisms for the Production Unit was identified as Staphylococcus spp (49.5 percent), Micrococcus spp (23 percent) and Bacillus spp and related genera (8.1 percent). The regularly used disinfectants for strains from the Group of Indicator Microorganisms showed a high microbicidal efficacy. Conclusion: the results provide information about the environmental bioburden, which will be useful for the understanding of the microbial entry points and spreading and the implementation of measures to prevent microbial contamination, so critical for manufacture of safe, pure and effective vaccines(AU)

Expression of bacterial genes in transgenic tobacco: methods, applications and future prospects

Tobacco is the most commonly used plant for expression of transgenes from a variety of organisms, because it is easily grown and transformed, it provides abundant amounts of fresh tissue and has a well-established cell culture system. Many bacterial proteins involved in the synthesis of commercial products are currently engineered for production in tobacco. Bacterial enzymes synthesized in tobacco can enhance protection against abiotic stresses and diseases, and provide a system to test applied strategies such as phytoremediation. Examples of bacterial gene expression in tobacco include production of antigen proteins from several human bacterial pathogens as vaccines, bacterial proteins for enhancing resistance against insects, pathogens and herbicides, and bacterial enzymes for the production of polymers, sugars, and bioethanol. Further improvements in the expression of recombinant proteins and their recovery from tobacco will enhance production and commercial use of these proteins. This review highlights the dynamic use of tobacco in bacterial protein production by examining the most relevant research in this field.

Selection of rotavirus strains G1 by doning and passaging on cell culture

A single B17.3 strain was selected from 45 Rotavirus strains by the method of CDC-Atlanta, USA - cloning and adaptation assay on cell culture. The strain is one of seed candidates for Rota vaccine production in Vietnam.