CD32 is a surface receptor protein and part of a large population of B cell

B cell

B cells are lymphocytes that play a large role in the humoral immune response . The principal functions of B cells are to make antibodies against antigens, perform the role of antigen-presenting cells and eventually develop into memory B cells after activation by antigen interaction...

 co-receptors, which act to modulate signaling.

It has a low-affinity for IgG antibodies and down-regulates antibody production in the presence of IgG. This feedback loops essentially lowers the production of IgG produced by B cells when there is a surplus in the body.

Monoclonal antibodies can distinguish between type A and type B.