IgG3 Fc Protein, Human (HEK293)

The constant region of immunoglobulin heavy chains, known as antibodies, represents membrane-bound or secreted glycoproteins produced by B lymphocytes. In the recognition phase of humoral immunity, these membrane-bound immunoglobulins act as receptors that, upon binding a specific antigen, trigger the clonal expansion and differentiation of B lymphocytes into immunoglobulin-secreting plasma cells. Secreted immunoglobulins play a pivotal role in the effector phase of humoral immunity, leading to the elimination of bound antigens. The antigen binding site is formed by the variable domain of one heavy chain, together with that of its associated light chain, resulting in each immunoglobulin having two antigen binding sites with remarkable affinity for a particular antigen. The variable domains undergo a V-(D)-J rearrangement and subsequent somatic hypermutations, enabling affinity maturation for a specific antigen after exposure and selection. Immunoglobulins are comprised of two identical heavy chains and two identical light chains, held together by disulfide linkages.