Fab fragment
Definition
The antigen-binding fragment of an antibody, consisting of one complete light chain paired with the variable and first constant domain of a heavy chain. Each IgG molecule has two Fab arms and therefore two identical antigen-binding sites.
Related terms
- Affinity
- The binding strength of a single antigen-binding site for one epitope, expressed as the equilibrium dissociation constant (Kd). A lower Kd indicates...
- Complementarity-determining regions (CDRs)
- Six hypervariable loops, three in the heavy-chain variable domain and three in the light-chain variable domain, that together form the antigen-binding site....
- Cross-reactivity
- The capacity of an antibody raised against one analyte to bind structurally related compounds. In RIA, cross-reactivity is the main driver of...
- Fc region
- The crystallisable fragment of an antibody, formed by the paired constant domains of the two heavy chains. The Fc region mediates effector...
- Monoclonal antibody (mAb)
- An antibody produced by a single hybridoma clone, so that every molecule in the preparation is identical, targets the same epitope, and...
Explained in
- Antibody Structure, Classes, and SpecificityThe antigen-binding fragment of an antibody, consisting of one complete light chain paired with the variable and first constant domain of a heavy chain. Each I...