IgD (Immunoglobulin D)

Immunoglobulin D (IgD) is a type of antibody found in small amounts in the blood and on the surface of immature B cells, which are immune cells responsible for producing antibodies. Its primary role is in the early development and regulation of the immune system, helping B cells recognize and respond to pathogens. IgD acts as a receptor on B cells to detect infections, prompting these cells to mature and produce other antibodies like IgG or IgA for longer-term immunity. While less understood than other antibodies, IgD plays a key role in initiating immune responses and maintaining immune system balance.