|
FcgII and FcgIII
low-affinity receptors for complexed IgG (Fc receptors or FcR) are
designated CD32 and CD16, respectively, and are expressed on many
cell types, including B lymphocytes, NK cells, granulocytes, monocytes,
macrophages, and platelets. Some antibody preparations may bind
via their Fc portions to FcR-bearing cells, resulting in high "background"
staining.
Mouse BD Fc Block is a purified rat IgG2b anti-mouse
CD16/CD32 monoclonal antibody (Cat. No. 553141 and 553142),1
while Rat BD Fc Block (Cat. No. 550270 and 550271) is a purified
mouse IgG1anti-rat CD32 monoclonal antibody.2
Mouse and Rat BD Fc Block can be used to block the Fc-mediated adherence
of antibodies* to mouse and rat FcR, respectively. Furthermore,
it has been reported that the Fc domain of the anti-mouse CD16/CD32
mAb 2.4G2 binds the FcgI receptor (CD64)
and blocks this additional FcR.1 Since Mouse and Rat
BD Fc Block are antigen-specific mAbs, anti-mouse CD16/CD32 and
anti-rat CD32, they may also be used as primary staining reagents
for detection of mouse and rat FcR-bearing cells, respectively.
Pre-incubation of mouse or rat cell suspensions with the respective
BD Fc Block for several minutes, prior to staining with specific
antibodies,* assures that any observed staining is due to the interaction
of the antigen-binding portion of the antibody with an antigen on
the cell surface. The following figures illustrate typical applications
of Mouse and Rat BD Fc Block.
*Experiments using unconjugated rat anti-mouse primary antibodies
or mouse anti-rat primary antibodies in the presence of BD Fc Block
must be carefully designed. Second-step reagents must be chosen
which will not cross-react with BD Fc Block, rat IgG2b
or mouse IgG1. BD Biosciences Pharmingen offers a selection
of isotype-specific anti-rat and anti-mouse immunoglobulin mAbs
which may be used for this purpose.
References:
- Unkeless, J.C. 1979. Characterization of a monoclonal
antibody directed against mouse macrophage and lymphocyte Fc receptors.
J. Exp. Med. 150: 580-596.
- BD Biosciences Pharmingen. Unpublished results.
|
