In monoclonal antibody technology,tumor cells that can replicate endlessly are fused with mammalian cells that produce an antibody.The result of this cell fusion is a"hybridoma,"which will continually produce antibodies.These antibodies are called monoclona because they come from onlyone type of cell,the hybridoma cell:antibodies produced by conventional methods,on the other hand,are derived from preparations containing many kinds of cells,and hence are called polyclonal.Anexample of how monoclon antibodies are derived is described below A myeloma is a tumor of the bone marrow that can be adapted to grow permanently in cell culture. When myeloma cells were fused with antibody-producing mammalian spleen cellsit was found that the large amouns of antibody.This product of cell fusion combined the desired qualities of the two different types of cells:the ability to grow continually,and the ability to produce large amounts of pure antibody. Because selected hybrid cells produce onyone specific antibody,they are more pure than the polyclonal antibodies produced by conventional techniques.Theyare potentially more effective tha conventional drugs in fighting disease,since drugs attack not only the foreign substance but the body's own cells as well,sometimes producing undesirable side effects such as nausea and allergic reactions Monoclonal antibodies attack the target molecule and only the target molecule,with no or greatly diminished side effects 2 12 In monoclonal antibody technology, tumor cells that can replicate endlessly are fused with mammalian cells that produce an antibody. The result of this cell fusion is a "hybridoma," which will continually produce antibodies. These antibodies are called monoclonal because they come from only one type of cell, the hybridoma cell; antibodies produced by conventional methods, on the other hand, are derived from preparations containing many kinds of cells, and hence are called polyclonal. An example of how monoclonal antibodies are derived is described below. A myeloma is a tumor of the bone marrow that can be adapted to grow permanently in cell culture. When myeloma cells were fused with antibody-producing mammalian spleen cells, it was found that the resulting hybrid cells, or hybridomas, produced large amounts of monoclonal antibody. This product of cell fusion combined the desired qualities of the two different types of cells: the ability to grow continually, and the ability to produce large amounts of pure antibody. Because selected hybrid cells produce only one specific antibody, they are more pure than the polyclonal antibodies produced by conventional techniques. They are potentially more effective than conventional drugs in fighting disease, since drugs attack not only the foreign substance but the body's own cells as well, sometimes producing undesirable side effects such as nausea and allergic reactions. Monoclonal antibodies attack the target molecule and only the target molecule, with no or greatly diminished side effects