Cell culturing method

Vogelmann H, Bischof A, Pape D, Wagner F (1978) In Alfermann AW, Reinhard E (eds) Production of natural compounds by cell culture methods. GSF, Munich, p 130... 

Cell Culture Methods Applied to Understanding Carotenoid Recognition and Action... 

Animal infectivity methods Some viruses do not cause recognizable effects in cell cultures but cause death in the whole animal. In such cases, quantification can only be done by some sort of titration in infected animals. The general procedure is to carry out a serial dilution of the unknown sample, generally at ten-fold dilutions, and samples of each dilution are injected into numbers of sensitive animals. After a suitable incubation period, the fraction of dead and live animals at each dilution is tabulated and an end point dilution is calculated. This is the dilution at which, for example, half of the injected animals die. Although such serial dilution methods are much more cumbersome and much less accurate than cell culture methods, they may be essential for the study of certain types of viruses. 

As well as overcoming many of the inherent problems associated with agriculture, plant tissue culture also offers a number of advantages over conventional animal cell culture methods currently being applied to produce biopharmaceutical proteins commercially [8], As plant culture media are relatively simple in composition and do not contain proteins, the cost of the process raw materials is reduced and protein recovery from the medium is easier and cheaper compared with animal cell culture. In addition, as most plant pathogens are unable to infect humans, the risk of pathogenic infections being transferred from the cell culture via the product is also substantially reduced. 

The BCS guidance allows for the use of tissue and cell culture methods to classify a drug substance as high or low permeability [6], The differences in laboratory methodologies for these assays suggest that a basic outline be... 

Volpe DA (2004) Permeability classification of representative fluoroquinolones by a cell culture method. AAPS PharmSci 6(2) article 13. 

New biomacromolecules are not the only recent development. Production methods for biomacromolecules have become more reasonable. Modem cell culture methods allow the production of gram quantities of proteins from bacterial, yeast, or mammalian cells (Hauser and Wagner 1997). Efficient methods are now available to recover the proteins from their producing cells (Seetharam and Sharma 1991). The breakthroughs in protein production allow for more expensive methods to be investigated for the delivery of the protein as the price of the protein drops, the price of the delivery device can go up while the cost of the final dose and profit for the company remains the same. The combination of new active proteins and the lower cost of the proteins has promoted increased research in the area of protein delivery. 

The permeability class boundary is based indirectly on the extent of absorption (fraction of dose absorbed, not systemic BA) of a drug substance in humans and directly on measurements of the rate of mass transfer across human intestinal membrane. Alternatively, nonhuman systems capable of predicting the extent of drug absorption in humans can be used (e.g., in vitro epithelial cell culture methods). In the absence of evidence suggesting instability in the gastrointestinal tract, a drug substance is considered to be highly permeable when the extent of absorption in humans is determined to be 90% or more of an administered dose based on a mass balance determination or in comparison to an intravenous reference dose. 

Ahrens, H. In "Production of Natural Compounds by Cell Culture Methods" Ed. by A.W. Alfermann and E. Reinhard, Gesell. Strahlen-und Umweltfor. Munich, 1978. 

Before implantation several in vitro tests were performed. For evaluation of a possible toxic reaction, we investigated the material and the whole devices in vitro with cell culture methods. Direct contact and extraction tests with a mouse fibroblasts cell line (L 929) and a neuroblastoma cell line (neuro-2-a) were performed according to the international standard ISO 10993 ( Biological Evaluation of Medical Devices ). The materials and devices showed no toxicity, i.e. no significant differences in membrane integrity of the cell membranes, mitochondrial activity and DNA synthesis rate. The neuro-2-a cell line is so sensitive that even small changes in process technology are detectable. The flexible polyimide structures proved to be non toxic. 

The choice of the assay to be performed depends on the context in which it will be used, the origin of the target cells, and the nature of the tested compounds. Among different assays, the parameters that vary are cell culture method, exposure time and concentrations, recovery time after exposure, and the method used to quantify the pharmaceutical effect. This topic is briefly covered in this chapter and is discussed in detail by Freshney (2005). 

The choice of cell culture method for cytotoxicity studies for a certain substance depends on the target cells and assay duration. Organ, spheroids, suspension cells, flask surface, and multi-well plate monolayers, as well as agar surface cultures can be employed. 

Figure 9.19 also suggests that there is an optimization window available developing new cell culture methods that provide cell concentrations in the range of 107 to 108 cells mL-1 could represent requirements still lower than in microbial fermentations, but at the same time a significant increase in the volumetric productivities of industrial animal cell processes. 

Wang A, Xia T, Ran P et al. (2002) Qualitative study of three cell culture methods. J Huazhong Univ Sci Technolog Med Sci 22 288-291... 

Plant cell culture methods constitute a most exciting part of food biotechnology research and development with many areas for food improvement, involving plant production, plant resistance and functionality, nutritional quality of plant foods and production of natural food ingredients (A9-51). 

Barnes D, Sirbasku D Sato GH (eds) (1984) Cell Culture Methods for Molecular and Cell Biology, vols 1, 2 3. Alan R. Liss, New York. 

Cell Culture Methods to Assess Drug Transport... 

Cell culture models to evaluate the pulmonary fate of inhaled drugs have not been used extensively for characterizing inhalation drugs. However, this technique is promising and will be briefly discussed. This section focuses on airway and alveolar epithelial models using cell lines and primary cell culture methods. 

Honegger P, Defaux A, Monnet-Tschudi F, Zurich MG (2011) Preparation, maintenance, and use of serum-free aggregating brain cell cultures. Methods Mol Biol 758 81-97... 

Volpe DA. Permeability Classification of Representative Fluoroquinolones by a Cell Culture Method. AAPSPharm Set 2004 6,Article 13. 

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