[Immunoglobulin D--peculiarities, biological function and clinical importance (author's transl)]

In the following paper an introducing survey about the properties of the immunoglobulin D is given, dealing with a possible biological function of this immunoglobulin as a triggering receptor on the surface of B-lymphocytes at the immune response. Moreover the at present advocating hypothesis of the maturation of the B-lymphocytes is explained. The importance of IgD by various diseases is discussed. High IgD-levels are a reference to a chronic antigenemia in the organism.