Antibody

A protein that is produced by B cells (in terminally differentiated B-cells known as plasma cells, these immunoglobulins are produced and secreted and are not cell surface bound) which recognize and bind to other proteins or substances (foreign or self antigens). Antibodies can be part of an immune response and help eradicate viruses and bacteria or may be part of an autoimmune destructive process in hematology such as autoimmune hemolytic anemia or immune mediated platelet destruction (e.g. ITP).