Nowadays pharmaceutical and medicinal biotechnology is an improved section of biotechnology. Production of different developed drugs, vaccines, artificial insulin, etc. are achievements of this section. Antibody engineering is one of the most developed parts of medicinal biotechnology. If an antibody is modified due to a specific application through recombinant DNA technology then it is called antibody engineering. It is also called hybrid antibody or recombinant antibody.
Some steps which are essential for doing antibody engineering are-
1. Development of a design that will prepare the antibody to be used for a specific application that means by which it will bind with a specific antigen.
2. Accumulation of all the DNA sequences that would generate this antibody into a suitable expression vector
3. Introduction of a vector in a myeloma cell line so that the modified antibody gene can express itself
4. Mass culture of the transfected clones containing modified antibody genes of myeloma cell line
5. Harvesting the produced recombinant antibodies. But it should be noticed that the myeloma cell line would not produce any antibody of its own.
Monoclonal antibody that is being used widely as therapeutic agent has been produced by using antibody engineering. For producing monoclonal antibody a myeloma cell line is fused with spleen cell line of mouse which has already immunized with the desired antigen. In this HAT medium is used as culture medium because it contain hypoxanthine, thymine and aminopterin. Unfused hybridoma cell cannot grow in HAT medium due to lack of HGPRT and unfused spleen cell cannot grow infinitely because they have limited life span. After producing monoclonal antibody it is purified by western blotting system. Now a day’s monoclonal antibodies are widely being used in cancer treatment. It is also used for treating autoimmune diseases like infliximab, adalimumab.