Fc Silent – Engineered Fc Domain

Fc Silent ppt4

Fc Silent™ represents a genetically engineered Fc domain developed at Absolute Antibody for research and assay development use. It contains key point mutations that abrogate binding of  Fc receptors (FcγR, FcR) abolishing antibody directed cytotoxicity (ADCC) effector function.

All our antibodies are available as Fc Silent™. Click here to view our catalogue. If you can’t find the antibody you are looking for, contact us and we will be able to generate it for you in often as little as 2 weeks.

Fc Silent™ Recombinant monoclonal antibodies and Fusion proteins benefit from the long plasma half-life (t1/2) associated with the Fc domain, with none of the cytolytic immune effector mechanisms associated with the wild-type Fc domain. In vitro applications for Fc Silent™ monoclonal antibodies and Fusion proteins include flow cytometry and immunohistochemistry (IHC). When studying immune cells, flow cytometry and IHC data analysis is complicated by non-specific background signal resulting from binding of the Fc domain to Fc receptors.


Flow-cytometry of BMDMs stained with wild-type (A) and Fc Silent™ (B) anti-F4/80 (Ab00106-8.1 and Ab00106-8.4) and isotype control antibodies, followed by fluorescently conjugated goat anti-rat secondary antibody. Using Fc Silent™ abolishes non-specific FcgR driven staining, making data cleaner and more accurate. Click image for more information.

For example, mouse IgG2a and rat IgG2b isotypes are known to bind strongly to Fc receptors irrespective of the test antibody specificity. Isotype controls are employed to allow the researcher to distinguish between specific and non-specific background signals.

As an example, we show how murine macrophages are labelled almost as strongly by a rat IgG2b isotype control as by an anti-F4/80. Switching to Fc Silent™ antibodies results in reliable data with background staining indistinguishable from a secondary-antibody-only control.

This also shows that Fc Silent™ antibodies are compatible with standard secondary antibodies.


Sensogram showing binding of rat wild-type (A) and Fc Silent™ (B) anti-F4/80 antibodies (Ab00106-8.1 and Ab00106-8.4) to immobilized murine FcγRs. BIAcore SPR binding analysis shows that the Fc Silent™ antibody (Ab00106-8.4) has been engineered to have no interaction with FcγRs. Click image for more data.


Absolute Antibody offer a diverse set of species specific Fc Silent™ domains (human, mouse, rabbit, rat, hamster) for our monoclonal antibody and Fusion protein catalog and custom service product range.

Contact us for more information.

View more Fc Silent™ binding data.



ELISA Data Mouse Fc-Silent and Wildtype Ab00106 v2

Direct Competitive Inhibition ELISA showing that Fc Silent format does not bind Fc Receptor. Click on image for more detail.