Size
~50 kDa (1/3 of IgG)
Valency
Monovalent (1 binding site)
Stability
More stable than scFv
Production
Bacterial, yeast, mammalian
Structure
Fab maintains the native antibody binding interface while being significantly smaller than full IgG.
- VH + CH1 domains (heavy chain)
- VL + CL domains (light chain)
- Connected by disulfide bonds
Key Applications
- Therapeutics - Reduced immunogenicity
- Diagnostics - Fast tissue penetration
- Crystallography - Easier to crystallize
- Research - Structural studies