What is the difference between an antigen and a hapten?
– The difference between an antigen and a hapten is that an antigen is a molecule that can trigger an immune response by itself, while a hapten is a molecule that can only trigger an immune response when attached to a larger carrier molecule.
– An antigen can bind to specific antibodies or T-cell receptors, while a hapten can only bind to specific antibodies.
– An antigen can be either foreign or self, while a hapten is usually foreign.
– An example of an antigen is a protein on the surface of a bacterium, while an example of a hapten is a drug molecule that binds to a protein in the body.
What is the mechanism of antibody binding to antigens?
– The mechanism of antibody binding to antigens is based on the specific and complementary interaction between the antigen-binding sites of the antibody and the epitopes of the antigen. The antigen-binding sites are located at the tips of the Y-shaped antibody molecule, and are formed by the variable regions of the heavy and light chains.
– The epitopes are the distinct regions of the antigen that can be recognized by the antibody. The binding is mediated by weak and noncovalent forces, such as hydrogen bonds, electrostatic interactions, van der Waals forces, and hydrophobic interactions.
– The strength and specificity of the binding depend on the shape, size, charge, and chemical composition of both the antigen and the antibody. The more similar and complementary they are, the more stable and effective the binding will be.
