Antibody Isotype Switching

Antibody isotype switching, also known as immunoglobulin class switching, isotypic commutation or class-switch recombination, is a biological mechanism that changes a B cell’s production of antibody from one type to another, such as from the isotype IgM to the isotype IgG (IgG1, IgG2, IgG3 and IgG4 for human, IgG1, IgG2a, IgG2b and IgG3 for mouse). During this process, the variable region of the antibody heavy chain is changed, but the constant region of the heavy chain stays the same. Since the variable region does not change, class switching does not affect antigen specificity. Instead, the antibody retains affinity for the same antigens, but can interact with different effector molecules. The antibody isotype switching process involves replacing only the constant region of the antibody while maintaining the variable regions, thus maintaining antibody’s specificity. Utilizing our proprietary technology and expertise, our scientists are able to modify antibody isotypes from any species, any isotypes (parent antibody) to any targeted antibody species and antibody isotypes.

Different classes of immunoglobulins, such as IgA, IgD, IgE, IgG and IgM, or subclasses such as different isotype IgGs, possess varying levels of antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) activity. Therapeutic antibody development requires selecting a specific class and subclass backbone, based on a desired ADCC and CDC activity profile. To identify optimal ADCC/CDC profiles for specific targets, it is advantageous to study the effects of antibody isotype switching, produced from the same variable region grafted to different class and subclass Fc domains.

Upon request, we will produce chimeric antibodies with different Fc domains using our proprietary cloning cassettes for all antibody classes and subclasses of the human (IgA, IgD, IgM, IgE, IgG1, IgG2, IgG3, and IgG4) and mouse (IgA, IgD, IgM, IgE, IgG1, IgG2a, IgG2b, and IgG3) species.

Cloning Vectors available:

Heavy Chain Light Chain
Human IgG1, IgG2, IgG3, IgG4 Igκ, Igλ2
Mouse IgG1, IgG2a, IgG2b, IgG3 Igκ, Igλ1, Igλ2
Rabbit IgG1 Igκ1, Igκ2, Igλ
Rat IgG2b Igκ, Igλ


Please contact us for pricing details.