Quantification of Heterologous Protein Levels in Transgenic Plants by ELISA

An IgG-type antibody is a Y-shaped protein whose arms form two identical antigen-binding sites that are highly variable between different molecules. The stem of the Y is part of the constant region of an antibody and has very limited diversity, which can be used to detect and quantitate antibodies. The interaction of an antibody with its antigen involves multiple noncovalent bonds, such as hydrogen bonds, electrostatic, Van der Waals, and hydrophobic attractive forces (1). The high specificity of this interaction enables an antibody to recognize its antigen even in the presence of a huge amount of contaminating antigens. This makes antibodies indispensable tools in a wide range of disciplines, including molecular biology.