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about IgG - (Mar/11/2002 )

Who can tell me about the difference between IgG1 ,IgG(Fab) and IgG(H+L)?


The IgG-class is divided into 4 subclasses (1-4). They differe in number and configuration of the S-S-Links between the two constant parts of the heavy chains.

Fab means that you are only having the Fragment antigen binding. Fab is produced by digesting IgG1 with the proteolytic enzyme Papain. Left over are the 2 antigen binding fragments (not linked to each other) and and the Fc (fragment crcrystallizable, part of the heavy chains which cannot bind antigen).

There are also F(ab')2. They are produced by proteolytic digestion with Pepsin. The 2 antigen binding fragments are still linked together because Pepsin cuts the IgG at a different site.

As far as I know means IgG (H+L) that your antibody can bind to both the heavy and the light chain of the antibody you want to dedect. (So the IgG (H+L) is an goat anti mouse IgG and binds murine antibodies)

Hopefully that helped a bit.