Anti-Human IgG4 Magnetic Beads

IgG4 is the least common of the four human IgG subclasses, accounting for only 3-6% of total serum IgG. It has a unique structure compared to other IgG subclasses, with a flexible hinge region and a CH2 domain loop that can adopt different conformations. IgG4 is unable to significantly bind C1q and activate the classical complement pathway, giving it reduced potential for immune activation. It can also undergo Fab arm exchange, where the two heavy chains separate and recombine randomly, resulting in bispecific antibodies unable to form immune complexes. The function of IgG4 varies depending on the context, with potential roles in dampening inflammation, acting as an antigen sink, and driving IgG4-related diseases characterized by elevated serum IgG4 and tissue infiltration by IgG4-positive plasma cells. Protein function: Constant region of immunoglobulin heavy chains. Immunoglobulins, also known as antibodies, are membrane-bound or secreted glycoproteins produced by B lymphocytes. In the recognition phase of humoral immunity, the membrane-bound immunoglobulins serve as receptors which, upon binding of a specific antigen, trigger the clonal expansion and differentiation of B lymphocytes into immunoglobulins- secreting plasma cells. Secreted immunoglobulins mediate the effector phase of humoral immunity, which results in the elimination of bound antigens (PubMed:22158414, PubMed:20176268). The antigen binding site is formed by the variable domain of one heavy chain, together with that of its associated light chain. Thus, each immunoglobulin has two antigen binding sites with remarkable affinity for a particular antigen. The variable domains are assembled by a process called V-(D)-J rearrangement and can then be subjected to somatic hypermutations which, after exposure to antigen and selection, allow affinity maturation for a particular antigen (PubMed:17576170, PubMed:20176268). [The UniProt Consortium]