Fab is the abstract of the Fragment of antigen band, which is a region of an antibody that can bind to an antigen. The Fab part includes a complete light chain and the VH and CH1 (Fd section ) of the large chain.
It has a weight of about 5 x 104. Both the light string and the heavy chain have a fixed region and a variable area, and there are disulfide links between the large and light chains. To know about western blot troubleshooting you can search the websites of service providers online.
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Currently, Fab immunoglobulin (Fa) parts can be available in the laboratory. Papain cuts the (immunoglobulin G) in the near terminal of this inter-heavy chain disulfide bond in the hinge region, which makes two equal monovalent antigen-binding fragments and a crystallizable part.
The monovalent antigen-binding parts are diminished as the FAB region, the crystallizable part is abbreviated as Fc part (Fragment crystallized). A Fab component is monovalent and can bind to antigen with no agglutination of precipitation. The Fc part has no antigen-binding action and is the site where IgG interacts with cells or molecules.
2. The preparation of Fab fragment
Now, there are methods of enzymatic hydrolysis, development using expression systems, and antibody building deletion using phage display technology to prepare it.
Enzymatic hydrolysis usually takes advantage of papain or pepsin to degrade individual immunoglobulin G to get products like F(ab')2, Fab, and Fc fragments; The groundwork using expression methods, which normally benefit from E. coli expression systems and lactation Animal expression system to produce Fab fragments.