👉 The Fc fluid, or the fragment of the Fc region of immunoglobulins (antibodies), refers to the flexible, unstructured portion of the heavy chain's constant region that extends beyond the antigen-binding site. This region is highly dynamic and plays a crucial role in mediating various non-covalent interactions with other molecules, such as complement proteins, Fc receptors on immune cells, and cytokines. These interactions facilitate processes like antibody-dependent cellular cytotoxicity (ADCC), complement activation, and immune regulation. The Fc fluid's flexibility allows it to adapt to different binding partners, thereby enhancing the antibody's effector functions and contributing to the overall immune response.
