Influence of Cell Disruption Methods on the Recovery and Immunogenicity of a Fusion Protein for a Therapeutic Cancer Vaccine Against HPV
by Miladys Limonta, Laura Varas, Jorge Valdés, Lourdes Zumalacárregui, Dayana Soler, Maelys Miyares, Alain B. Alfonso, Milaid Granadillo, and Isis Torrens
Volume 14, Issue 4 (Winter 2015/2016)
Two cell disruption methods, mechanical and chemical, were applied for the recovery of a fusion protein named CIGB 550-E7, expressed on Escherichia coli grown in defined saline media. A comparison of the methods was done, and various operating parameters for each technique were optimized to obtain the maximum disruption efficiency and CIGB 550-E7 protein release. The mechanical disruption’s yield and recovery were 1.24 and 1.37 times higher than those obtained with chemical disruption. Modified conditions were assayed for the CIGB 550-E7 obtained by chemically defined media using the mechanical and chemical cell disruption methods. The processes we developed allowed us to obtain an active pharmaceutical ingredient that fulfills the requirements stipulated by the regulatory authorities in terms of purity and lipopolysaccharide contaminants. In addition, the CIGB 550-E7 obtained from both methods showed similar biological activity so that either method could be used. Finally, a cost/benefit relationship (CBR) analysis was done for both disruption methods, and the CBR value for mechanical cell disruption demonstrated that this was the most feasible choice...
Citation:
Limonta M, Varas L, Valdés J, Zumalacárregui L, Soler D, Miyares M, Alfonso AB, Granadillo M, Torrens I. Influence of cell disruption methods on the recovery and immunogenicity of a fusion protein for a therapeutic cancer vaccine against HPV. BioProcess J, 2016; 14(4): 22–9. http://dx.doi.org/10.12665/J144.Limonta.
Posted online January 12, 2016.
Biopharmaceutical Manufacturing: Current Titers and Yields in Commercial-Scale Microbial Bioprocessing
by Ronald A. Rader and Eric S. Langer
Volume 14, Issue 4 (Winter 2015/2016)
This article reports the average titers and yields currently attained with commercially manufactured biopharmaceuticals expressed by microbial systems such as E. coli and yeasts. A recent BioProcessing Journal article comparably covered results from the first phase of this study concerning historical titers and yields attained for commercial-scale biopharmaceutical production using mammalian cells (e.g., CHO). As with this prior mammalian component, public domain data concerning titers and yields attained with microbially manufactured products were obtained using all available sources. These included a review of available literature and direct contact with over 200 bioprocessing professionals identified as involved in relevant product research and development, and manufacturing. Unexpectedly, current microbial titers with commercially manufactured products were found to be consistent with those previously determined for mammalian products. However, purification yields attained with microbial manufacturing averaged only about 15%. This is much lower than with mammalian products yielding approximately 69%. Despite low downstream yields, microbial bioproduction continues to be considered less costly, simpler, faster, and generally more economical than mammalian manufacturing...
Citation:
Rader RA, Langer ES. Biopharmaceutical manufacturing: current titers and yields in commercial-scale microbial bioprocessing. BioProcess J, 2016; 14(4): 51–5. http://dx.doi.org/10.12665/J144.Langer.
Posted online January 12, 2016.
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Direct, Real-Time Antibody-Based Quantification of Baculovirus
by Michael Artinger, April Birch, Tyler Gates, Christopher Kemp, and Michael W. Olszowy
Volume 14, Issue 4 (Winter 2015/2016)
The impact of viruses—in geopolitical human health issues, in the production of vaccines and recombinant proteins, and in gene therapy and cancer treatments—highlights the need for a better understanding of the systems that are dependent upon them. A primary barrier to recognizing the full potential of these life-saving biomedical approaches is the scarcity of analytical methods capable of providing biologically relevant information without hindering the pace of development and production. ViroCyt® is a Colorado-based biotechnology company with one overriding focus: Enabling the rapid and specific quantification of viruses and virus-related particles. The ViroCyt Virus Counter® was designed to meet this objective. Until recently, the primary method employed by the Virus Counter for detecting virus was ComboDye, which utilized a general fluorogenic nucleic acid stain and a general fluorogenic protein stain to simultaneously label intact virus particles. The advantage of this approach is that it provides a broadly applicable reagent capable of quantifying many virus types. The disadvantage is that crude and/or complex matrices, in which there is high nucleic acid and/or protein background, can complicate the detection of individual virus particles. To address this issue, and to allow innovation to drive the technology into an expanded number of virus systems, ViroCyt recently created a second portfolio of reagents called ViroTag®. This technology employs fluorescently tagged antibodies specific for the virus of interest. The first members of this product line to be launched target two high-value viruses: baculovirus and human adenovirus. In this article, we focus on the application of the ViroTag system for rapid quantification during the bioprocessing of baculovirus-derived systems...
Citation:
Artinger M, Birch A, Gates T, Kemp C, Olszowy MW. Direct, real-time antibody-based quantification of baculovirus. BioProcess J, 2016; 14(4): 15–21. http://dx.doi.org/10.12665/J144.Artinger.
Posted online January 12, 2016.
Long-Term CB.Hep-1 Monoclonal Antibody Production in a Single-Use Bioreactor on a Rocker Platform with Serum- and Protein-Free Media
by Alberto Galván, Rodolfo Valdés, Marcos González, Hasel Aragón, Daily Hernández, Sigifredo Padilla, Leonardo Gómez, David Gailán, Yanet Villegas, Andrés Tamayo, Adelma Pérez, Bárbara Pérez, Maylín Lao, Yodelis Calvo, Aneet Fernández, Lianys Lee, Jania Suarez, Judey García, and Eduardo Ojito
Volume 14, Issue 4 (Winter 2015/2016)
Rocker bag bioreactors have been used successfully in cultivating cells because they provide good nutrient distribution and cell suspension while eliminating the need to validate cleaning and sterilization. Therefore, this study examined the long-term performance of a 50 L single-use bag bioreactor on a rocking platform in CB.Hep-1 monoclonal antibody (mAb) production. For such a purpose, the bioreactor was operated in a continuous mode with a mixture of serum-free media (SFM) for 62 days, and with protein-free medium (PFM) for another 62 days. Stationary phase culture results with SFM were: cell concentration of 1.57 ± 0.2 × 106 cells mL-1, specific growth rate of (μ)=0.0202, cell viability of 91.1 ± 6.4%, mAb concentration of 44.6 ± 11.1 μg mL-1, cell-specific secretion of 28.8 ± 8.1 pg cell-1 , and mAb yield of 42.4 ± 4.0 mg L-1. After SFM was replaced by PFM, there were statistically different results (p<0.05) in a cell concentration of 2.56 ± 0.2 × 106 cells mL-1, cell viability of 97.0 ± 1.1%, mAb concentration of 90.1 ± 28.2 μg mL-1, and mAb yield of 76.6 ± 10.6 mg L-1. However, the cell-specific secretion of 38.0 ± 6.0 pg cell-1 was statistically similar, but only with the first batch run with SFM. Average purification recovery from the SFM and PFM supernatants was 74.6 ± 7.9% and 70.9 ± 11.2%, respectively. The recovery and biochemical properties of the CB.Hep-1 mAb cultured with either media composition were similar to those found with CB.Hep-1 mAb produced by ascites. Regardless of whether SFM or PFM is used, it can be concluded that the 50 L single-use bag bioreactor on a rocker platform was suitable for long-term CB.Hep-1 production and can result in a 36 g yield in 125 days...
Citation:
Galván A, Valdés R, González M, Aragón H, Hernández D, Padilla S et al. Long-term CB.Hep-1 monoclonal antibody production in a single-use bioreactor on a rocker platform with serum- and protein-free media. BioProcess J, 2016; 14(4): 4–13. http://dx.doi.org/10.12665/J144.Valdes.
Posted online January 12, 2016.
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