avidity

Examples of avidity in the following topics:

• Antibody Functions

  • The term avidity describes binding by antibody classes that are secreted as joined, multivalent structures (such as IgM and IgA).
  • Although avidity measures the strength of binding, just as affinity does, the avidity is not simply the sum of the affinities of the antibodies in a multimeric structure.
  • The avidity depends on the number of identical binding sites on the antigen being detected, as well as other physical and chemical factors.
  • Typically, multimeric antibodies, such as pentameric IgM, are classified as having lower affinity than monomeric antibodies, but high avidity.
  • (a) Affinity refers to the strength of single interactions between antigen and antibody, while avidity refers to the strength of all interactions combined.