Abstract

Introduction. Antibodies are an important class of proteins produced when a foreign entity elicits an immune response in the body. There are 5 major classes of antibodies, IgM, IgG, IgA, IgD, and IgE. The structure and immune function of immunoglobulins differ. An antibody contains two light and two heavy chains, which are linked by multiple disulphide bonds. Variable regions are found on light and heavy chains, known as the fragment antigen-binding (Fab) region, and a constant region, which is also known as the fragment crystallizable (Fc) region. Antibodies are, as a class, broad-spectrum antimicrobial agents with activity against all classes of pathogens. However, individual antibodies are usually pathogen-specific. Monoclonal antibodies, which specifically recognize one epitope of the cognate antigen, can be generated by using antibody engineering techniques such as hybridoma, phage display, and transgenic technologies. Removal of the entire constant region or part of the whole Fc portion generates antibody fragments such as Fab, scFv, and diabodies. Better tissue or tumor penetration characteristic of antibody fragments make them suited for the therapy overusing the whole antibody, hence most suited for therapy. Aim. Nowadays, it is possible to use antibodies for different therapeutic applications by modifying either their structural or functional properties.