Monoclonal Antibody hybridoma

Figure 4.33. Preparation of Monoclonal Antibodies. Hybridoma cells are formed by fusion of antibody-producing cells and myeloma cells. The hybrid cells are allowed to proliferate by growing them in selective medium. They are then screened to determine which ones produce antibody of the desired specificity. [After C. Milstein. Monoclonal antibodies. Copyright 1980 by Scientific American, Inc. All rights reserved.]...

Biotechnology products are pharmaceutical products prepared by industrial processes that involve the use of biological systems such as fermentation or tissue culture. For some industries, these processes involve the use of genetically engineered organisms. The preparation of products generally involves recombinant DNA, monoclonal antibody/hybridoma, continuous cell lines, and cellular therapy technology. 

Larsson, A., and Mellstedt, H. (1992) Chicken antibodies a tool to avoid interference by human anti mouse antibodies in ELISA after in vivo treatment with murine monoclonal antibodies. Hybridoma, 11, 33 39. 

R. H. Kennett, T. J. Mckeam, K. B. Bechtol, in Monoclonal antibodies. Hybridomas A new dimension in biological analyses. Plenum Press, New York and London, 1980. 

Hybridoma technology First method of producing monoclonal antibodies (hybridomas not stable) Kohler and Milstein [259]... 

Product formation kinetics in mammalian cells has been studied extensively for hybridomas. Most monoclonal antibodies are produced at an enhanced rate during the Gq phase of the cell cycle (8—10). A model for antibody production based on this cell cycle dependence and traditional Monod kinetics for cell growth has been proposed (11). However, it is not clear if this cell cycle dependence carries over to recombinant CHO cells. In fact it has been reported that dihydrofolate reductase, the gene for which is co-amplified with the gene for the recombinant protein in CHO cells, synthesis is associated with the S phase of the cell cycle (12). Hence it is possible that the product formation kinetics in recombinant CHO cells is different from that of hybridomas. 

Mammalian Cells Unlike microbial cells, mammalian cells do not continue to reproduce forever. Cancerous cells have lost this natural timing that leads to death after a few dozen generations and continue to multiply indefinitely. Hybridoma cells from the fusion of two mammalian lymphoid cells, one cancerous and the other normal, are important for mammalian cell culture. They produce monoclonal antibodies for research, for affinity methods for biological separations, and for analyses used in the diagnosis and treatment of some diseases. However, the frequency of fusion is low. If the unfused cells are not killed, the myelomas 1 overgrow the hybrid cells. The myelomas can be isolated when there is a defect in their production of enzymes involved in nucleotide synthesis. Mammahan cells can produce the necessary enzymes and thus so can the fused cells. When the cells are placed in a medium in which the enzymes are necessaiy for survival, the myelomas will not survive. The unfused normal cells will die because of their limited life span. Thus, after a period of time, the hybridomas will be the only cells left ahve. 

Monoclonal antibodies are derived from a single, monospecific B cell clone. Monoclonal antibodies can be obtained from hybridoma cells that result from the fusion of antibody-producing B cells with immortal cells of a myeloma cell line. 

Biotech products based on recombinant DNA, gene expression or hybridoma/monoclonal antibody technologies. 

Most work on chemical stress was done with hybridoma cells since they are widely used for industrial relevant monoclonal antibody production but... 

Hybridomas Provide Long-Term Sources of Highly Useful Monoclonal Antibodies... 

Knowing the importance of PGA for the ion exchange in the cell wall, we considered the production of monoclonal antibodies (Ab) to homopolygalacturonic acid. We produced one IgGl hybridoma, named 2F4, that appeared to be specific of PGA [11]. 

Monoclonal antibody, an antibody produced by a single clone of cells (specifically, a single clone of hybridoma cells) and therefore a single pure homogeneous type of antibody that binds to the same target. 

Fig. 15.7 Glycosylation of an antibody produced in tobacco plants expressing a human 3(l,4)-galactosyltransferase. As illustrated for Guy sl3 in Fig. 15.4, when the monoclonal antibody Mgr48 is produced in wild type tobacco plants (left panel), its glycosylation is structurally different and more heterogeneous than that of its mammalian counterpart (lower panel). When this antibody is produced in tobacco plants expressing the human galactosyltransferase (right panel), 30% of its N-glycans show terminal N-acetyllactosamine sequences identical to those carried by this antibody when it is produced in hybridoma cells.

Generation of antibodies that can recognize and bind to specific viruses is straightforward. A sample of live or attenuated virus, or a purified component of the viral caspid, can be injected into animals to stimulate polyclonal antibody production (or to facilitate monoclonal antibody production by hybridoma technology). Harvested antibodies are then employed to develop specific immunoassays that can be used to screen test samples routinely for the presence of that specific virus. Immunoassays capable of detecting a wide range of viruses are available commercially. The sensitivity, ease, speed and relative inexpensiveness of these assays render them particularly attractive. 

The basis of monoclonal antibody production by hybridoma technology... 

Monoclonal antibody technology entails isolation of such B-lymphocytes, with subsequent fusion of these cells with transformed (myeloma) cells. Many of the resultant hybrid cells retain immortal characteristics, while producing large quantities of the monospecific antibody. These hybridoma cells can be cultured long term to effectively produce an inexhaustible supply of the monoclonal antibody of choice. 

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