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Vaccine Production (vaccine + production)
Selected AbstractsRelevance of incubation temperature for Vibrio salmonicida vaccine productionJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2002D.J. Colquhoun Aims:,To investigate the relationships between water temperature, bacterial growth, virulence and antigen expression in Vibrio salmonicida, the causal agent of cold water vibriosis in Atlantic salmon (Salmo salar L.). Methods and Results:,The significance of sea temperature was investigated using historical clinical and oceanographic data. An upper threshold for disease of approx. 10°C was established. The effects of culture temperature and media type on bacterial growth were studied on solid and in liquid media. The highest rates of cell division were identified at 15°C on solid media and 10°C in liquid media. Outer membrane protein (OMP) expression and serological response in Atlantic salmon were studied using sodium dodecyl sulphate-polyacrylamide gel electrophoresis, Western blotting and enzyme-linked immunosorbent assay. A novel 76-kDa OMP produced in unshaken cultures at 10°C was not found to stimulate a specific humoral response. Conclusions:,Diagnostic agar plate-based incubation of suspected V. salmonicida should be carried out at 15°C. High yield broth cultures for vaccine production should be incubated at 10°C or lower. Significance and Impact of the Study:,This study is, to the best of our knowledge, the first to identify different optimal temperatures in a bacterial species cultured on physically different types of media. The evidence presented suggests that V. salmonicida and possibly other bacteria destined for vaccine use in poikilothermic organisms should be cultured at temperatures consistent with that at which disease occurs. [source] Measurement of key metabolic enzyme activities in mammalian cells using rapid and sensitive microplate-based assaysBIOTECHNOLOGY & BIOENGINEERING, Issue 3 2010R. Janke Abstract Sensitive microplate-based assays to determine low levels of key enzyme activities in mammalian cells are presented. The enzyme platform consists of four cycling assays to measure the activity of 28 enzymes involved in central carbon and glutamine metabolism. The sensitivity limit of all cycling assays was between 0.025 and 0.4,nmol product. For the detection of glutaminase activity, a new glutamate cycle system involving the enzymes glutamate dehydrogenase and aspartate transaminase was established. The relative standard deviation of the method was found to be 1.7% with a limit of detection of 8.2,pmol and a limit of quantitation of 24.8,pmol. Hence, cell extracts could be highly diluted to reduce interferences caused by other components in the extract, which in addition minimized underestimates or overestimates of actual enzyme activities. Since substrate concentrations could be maintained at a nearly constant level throughout the assay product accumulation during the reaction was low, which minimized product inhibition. As an example, the enzyme platform was used to investigate maximum enzyme activities of stationary-phase MDCK cells grown in serum-containing GMEM medium as typically used in influenza vaccine production. Biotechnol. Bioeng. 2010;107: 566,581. © 2010 Wiley Periodicals, Inc. [source] Development and characterization of three new diploid cell lines from Labeo rohita (Ham.)BIOTECHNOLOGY PROGRESS, Issue 4 2010Wazir S. Lakra Abstract Development of cell lines from fish for identifying the pathogenesis of viral diseases and for vaccine production against viral and bacterial diseases is imperative where they are of commercial importance. Three new diploid fish cell lines (RF, RH, and RSB) were developed from fin, heart, and swim bladder of an Indian major carp, Labeo rohita, commonly called Rohu. All the cell lines were optimally maintained at 28°C in Leibovitz-15 medium supplemented with 10% FBS. The propagation of RH and RSB cells was serum dependent, with a low plating efficiency (<16%), whereas RF cells showed 20% efficiency. The cytogenetic analysis revealed a diploid count of 50 chromosomes. The cells of RF and RSB were found to be epithelial, where as the cells of RH were mostly fibroblastic. The viability of the RF, RH, and RSB cell lines was 75, 70 and 72%, respectively after 6 months of storage in liquid nitrogen. The origin of the cell lines was confirmed by the amplification of 496 and 655 bp fragments of 16S rRNA and Cytochrome Oxidase Subunit I (COI) of mtDNA. The new cell lines would facilitate viral disease diagnosis and genomic studies. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] Fed-batch production of tetanus toxin by Clostridium tetaniBIOTECHNOLOGY PROGRESS, Issue 1 2010Fernando Fratelli Abstract This study deals with the effects of the initial nitrogen source (NZ Case TT) level and the protocol of glucose addition during the fed-batch production of tetanus toxin by Clostridium tetani. An increase in the initial concentration of NZ Case TT (NZ0) accelerated cell growth, increased the consumption of the nitrogen source as well as the final yield of tetanus toxin, which achieved the highest values (50,60 Lf/mL) for NZ0 , 50 g/L. The addition of glucose at fixed times (16, 56, and 88 h) ensured a toxin yield (,60 Lf/mL) about 33% higher than those of fed-batch runs with addition at fixed concentration (,45 Lf/mL) and about 300% higher than those obtained in reference batch runs nowadays used at industrial scale. The results of this work promise to substantially improve the present production of tetanus toxin and may be adopted for human vaccine production after detoxification and purification. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] DNA Depletion by Precipitation in the Purification of Cell Culture-Derived Influenza VaccinesCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 6 2010T. Kröber Abstract A pilot study for the purification of cell culture-derived human influenza virus is presented, which focuses on the early removal of DNA by precipitation. Strains of influenza virus were propagated using Madin Darby canine kidney cells as a host. A harvesting time of about 72 h postinfection was chosen to minimize the level of impurities (host cell DNA and protein). Cell culture supernatant was clarified by centrifugation and the performance of this operation was characterized on the basis of Sigma theory. An average clarification efficiency of 93,% (based on turbidity) and a product yield of 85,% (based on hemagglutination activity) were obtained at a load of 1.6,·,10,8 m s,1. Furthermore, the applicability of Sigma theory for scale-up studies using two different laboratory centrifuges was verified. Selective precipitation of DNA was achieved by the addition of polyethyleneimine (PEI). Full factorial design was applied to optimize selectivity considering pH, ionic strength, and the concentration and molecular weight of PEI. Under optimized conditions, treatment with PEI resulted in a reduction of DNA to 15,% of the initial amount, while 86,% of virions (based on neuraminidase activity) were recovered. The subsequent concentration of virions was realized by tangential-flow ultrafiltration. Recovery based on hemagglutination activity was determined to 63,% on average. Including the previous precipitation step, overall reduction in DNA after tangential-flow ultrafiltration was 500-fold. These results indicate that the suggested unit operations are suited for the early depletion of DNA in cell culture-derived influenza vaccine production. [source] | ||||||||||