Antibodies are glycoproteins belonging to the immunoglobulin superfamily. Nivolumab is a fully human monoclonal immunoglobulin G4 antibody to PD-1. Immunoglobulins are glycoproteins in the immunoglobulin superfamily that function as antibodies. The positive B cell signaling is initiated by binding of foreign antigen to surface immunoglobulin. Agglutinating antibodies such as immunoglobulin M and immunoglobulin G are produced against the bacteria. B cells specifically can divide when they encounter an antigen matching their immunoglobulin. The terms "antibody" and "immunoglobulin" are often used interchangeably. Most people with PSC have evidence of autoantibodies and abnormal immunoglobulin levels. There have also been attempts to treat infections using ribavirin, intravenous immunoglobulin, or alpha interferon. Somatic hypermutation involves a programmed process of mutation affecting the variable regions of immunoglobulin genes. Corticosteroids or intravenous immunoglobulin (IVIG) may be useful in certain cases. Examples include intravenous immunoglobulin and propofol. Thyroglobulin has been shown to interact with Binding immunoglobulin protein. Treatment with intravenous immunoglobulin usually resolves the anemia although relapse can occur. I membrane protein that is a member of the immunoglobulin superfamily.