ASIF BIOTECH

Removing bovine endogenous retrovirus (BERV) or Bovine exogenous retrovirus (BERV) from plasma protein is important to avoid contamination of biological products. One common method for removing BET from plasma protein is through DEAE (Diethylaminoethyl) resin anion-exchange chromatography. A study by Tsai et al. (2013) titled "Removal of Bovine Exogenous Retrovirus from Human Plasma-Derived Products Using DEAE Anion-Exchange Chromatography" published in the Journal of Virological Methods, describes the use of DEAE resin anion-exchange chromatography to effectively remove BET from human plasma-derived products such as albumin, immunoglobulin, and coagulation factor IX. The study found that DEAE resin anion-exchange chromatography was able to effectively remove BET proteins while maintaining the activity and purity of the plasma proteins. Another study by Wang et al. (2015) titled "Removal of bovine endogenous retrovirus from human plasma-derived protein using DEAE ani

Removing bovine endogenous retrovirus (BERV) or Bovine exogenous retrovirus (BERV) from plasma protein through DEAE (Diethylaminoethyl) resin anion-exchange chromatography is a common method. DEAE resin is a type of anion-exchange resin that can be used for the purification of plasma proteins. Here are the general steps for removing BET from plasma protein through DEAE resin anion-exchange chromatography: 1.     Prepare the sample: The plasma protein sample should be clarified and filtered to remove any debris or contaminants before being loaded onto the column. 2.     Equilibrate the column: The column should be equilibrated with a buffer that is compatible with the DEAE resin. A common buffer used is a low salt buffer such as Tris-HCl, pH8.0 3.     Load the sample: The plasma protein sample is then loaded onto the column, and the BET proteins are retained by the DEAE resin while the other proteins pass through. 4.     Wash the column: The column is washed with a buffer to remove any

The pH of the culture medium is an important parameter that affects the growth and productivity of cells in a bioreactor. The pH can affect the solubility, stability and activity of enzymes, as well as the uptake and metabolism of nutrients. In the case of rituximab production, the pH can affect the stability and activity of the protein, as well as the productivity of the cells. Optimal pH for rituximab production in Chinese hamster ovary (CHO) cells usually ranges from 7.0 to 7.5. A pH that is too low or too high can cause the protein to denature or aggregate, reducing its activity and stability. Additionally, a pH that is too low or too high can also cause stress to the cells, reducing their productivity. A research article "Development of a high-titer, high-density fed-batch process for the production of Rituximab in Chinese Hamster Ovary (CHO) cells" by Wang et al. (2015) aimed to improve the production of rituximab by developing a high-titer and high-density fed-batc

A research article "Comparison of different serum-free media for the growth and productivity of Chinese hamster ovary cells" by Chen et al. (2018) aimed to compare the performance of different serum-free media for the growth and productivity of Chinese hamster ovary (CHO) cells, a commonly used host for recombinant protein production. The study compared several commercially available serum-free media, including Gibco's CD CHO-S, Thermo Fisher's CD CHO-SFM, and Biochrom's CD Opti-CHO, as well as a custom medium developed by the authors. The study evaluated the cell growth, viability, and productivity of the cells in each of the media. The results of the study showed that all of the serum-free media were able to support the growth and viability of the CHO cells, but there were significant differences in the productivity of the cells. The custom medium developed by the authors showed the highest productivity of the cells, followed by the Biochrom's CD Opti-CH

Tocilizumab (Actemra) is a humanized monoclonal antibody that targets the interleukin-6 (IL-6) receptor, which is involved in the inflammatory response. It is used to treat rheumatoid arthritis, systemic juvenile idiopathic arthritis and other inflammatory conditions. It is produced using recombinant DNA technology in Chinese hamster ovary (CHO) cells. One research article "Development of an efficient and scalable fed-batch culture process for the production of tocilizumab in Chinese hamster ovary cells" by Li et al. (2019) aimed to optimize the production of tocilizumab using a fed-batch cultivation system in CHO cells. The study aimed to improve the yield and quality of the protein, and to develop a process that can be easily scaled up for industrial production. The results of the study showed that the yield of tocilizumab was significantly improved by optimizing the culture conditions, such as the temperature, pH, and dissolved oxygen, as well as by using a specific

Adalimumab is a recombinant human monoclonal antibody that is used to treat a variety of inflammatory diseases, such as rheumatoid arthritis, psoriasis, and Crohn's disease. It is produced using recombinant DNA technology in Chinese hamster ovary (CHO) cells. A research article "Development of a high-titer, high-density fed-batch process for the production of adalimumab in CHO cells" by Chen et al. (2018) aimed to improve the production of adalimumab by developing a high-titer and high-density fed-batch process. The study used a CHO cell line that had been modified to express the adalimumab gene. The cells were grown in a culture medium containing glucose, amino acids, and a proprietary feed supplement, and the culture conditions were optimized to achieve high yields of the protein. The results of the study showed that a high yield of adalimumab (over 2g/L) was achieved using the fed-batch cultivation system. The study also found that the specific productivity of th

  Bevacizumab is a recombinant humanized monoclonal antibody that targets the vascular endothelial growth factor (VEGF) protein. It is used to treat a variety of cancers, such as colorectal, lung, glioblastoma, and renal cell carcinomas. Bevacizumab was first approved by the US Food and Drug Administration (FDA) in 2004 for the treatment of metastatic colon and lung cancer. The development of bevacizumab began in the late 1990s, when scientists at Genentech, a subsidiary of Roche, recognized the potential of targeting VEGF for the treatment of cancer. The VEGF protein is known to promote the growth of new blood vessels, which is essential for the growth and spread of tumors. By targeting VEGF, bevacizumab can inhibit the growth of new blood vessels and thus, slow the growth of tumors. To develop bevacizumab, Genentech scientists first identified a mouse monoclonal antibody that binds to VEGF, and then humanized it to minimize the potential for an immune response. The humanized anti

PID (Proportional-Integral-Derivative) control is a control loop feedback mechanism used to regulate the temperature, pH, and other process variables in a bioreactor. It is commonly used in the control systems of bioreactors to maintain a steady state and avoid large fluctuations in the process variables. The PID controller calculates the error between the desired set point and the current process variable and then generates a correction signal to adjust the process. The correction signal is generated by combining three control terms: Proportional control: This term generates a correction signal that is proportional to the error between the set point and the current process variable. The proportionality constant is known as the proportional gain (Kp). Integral control: This term generates a correction signal that is proportional to the integral of the error over time. The integral gain (Ki) is used to adjust this term. Derivative control: This term generates a correction signal

The volumetric mass transfer coefficient (Kla) and mixing time are important parameters in the design and optimization of bioreactors for mammalian cell culture, such as CHO cell lines. To calculate Kla, one common method is to use the dynamic gassing-out method. In this method, a known volume of gas is injected into the bioreactor, and the rate of oxygen consumption by the cells is measured over time. The Kla can then be calculated using the following equation: Kla = (d(DO) / dt) / (C*(S-X)) Where d(DO)/dt is the rate of oxygen consumption, C is the oxygen solubility in the liquid, S is the oxygen saturation concentration, and X is the dissolved oxygen concentration in the liquid. To calculate mixing time, one common method is to use the "tracer response method". In this method, a small amount of a non-toxic tracer, such as fluorescein, is added to the bioreactor. The mixing time can then be calculated as the time taken for the tracer to be homogeneously distributed

Darbepoetin alfa is a recombinant protein that is used to treat anemia caused by chronic kidney disease and cancer chemotherapy. It is produced using recombinant DNA technology in Chinese hamster ovary (CHO) cells. A recent research article, "High-yield production of darbepoetin alfa in fed-batch Chinese hamster ovary cells" by Lee et al. (2019), aimed to investigate the production of darbepoetin alfa in a fed-batch cultivation system. The study used a recombinant CHO cell line that had been modified to express the darbepoetin alfa gene. The cells were grown in a culture medium containing glucose and amino acids, and the culture conditions, such as temperature, pH, and dissolved oxygen, were optimized to achieve high yields of the protein. The results of the study showed that a high yield of darbepoetin alfa (over 20mg/L) was achieved using the fed-batch cultivation system. The study also found that the specific productivity of the cells was highest during the transition

The effect of temperature on rituximab production has been studied in several research articles. Generally, it has been found that the optimal temperature for rituximab production is around 37°C, which is the same temperature that is optimal for the growth and metabolism of CHO cells. However, some studies have shown that slightly lower temperatures may also be beneficial for rituximab production. A study by Krieg et al. (2010) showed that reducing the temperature to 33°C during the stationary phase of the culture increased the yield of a monoclonal antibody (similar to rituximab) by 2.5-fold compared to cultivation at 37°C. Similarly, another study by Wang et al. (2020) found that a temperature of 34°C during the stationary phase resulted in a 1.5-fold increase in the yield of rituximab compared to the exponential phase. On the other hand, a study by Hong et al. (2017) found that a temperature of 32°C resulted in a significant reduction in the yield of rituximab compared to 37

Rituximab is a monoclonal antibody that is used to treat various types of cancer, such as non-Hodgkin's lymphoma and rheumatoid arthritis. It is produced in a recombinant form using Chinese hamster ovary (CHO) cells. One of the main challenges in the production of rituximab is to achieve high yields of the protein while maintaining its quality and stability. A recent research article, "Rituximab production in fed-batch Chinese hamster ovary cells at the stationary phase" by Wang et al. (2020), aimed to investigate the effect of the culture phase on the yield and quality of rituximab. The study used a fed-batch cultivation system in which the cells were grown in a culture medium containing glucose and amino acids. The cells were harvested at different stages of growth, including the exponential phase, the transition phase, and the stationary phase. The results of the study showed that the highest yield of rituximab was achieved when the cells were harvested at the stationa