Yes, there are several FcR blocking reagents that can be used in vitro to block Fc receptors on human macrophages. Fc receptors are involved in the binding and uptake of immune complexes and play a role in various immune responses.

One commonly used FcR blocking reagent is human immunoglobulin G (IgG). IgG can saturate the Fc receptors on macrophages, preventing them from binding to other antibodies or immune complexes. Human IgG can be obtained commercially and used at a high concentration in the culture medium.

Another option is the use of monoclonal antibodies specifically targeting Fc receptors. For example, anti-CD16 (FcγRIII) antibodies can block the FcγRIII receptor on macrophages. Similarly, anti-CD32 (FcγRII) antibodies can block the FcγRII receptor. These antibodies can be obtained from commercial sources and used at the appropriate concentrations for blocking.

It's important to note that the choice of FcR blocking reagent may depend on the specific Fc receptors involved and the experimental setup.

All the best with your experiment

Saif Wahid Thank you so much! This is very helpful! I'll look into it.