Immunoglobulin

**Semantic type:** Amino Acid, Peptide, or Protein|Immunologic Factor

**Definition:** Any of the structurally related glycoproteins that function as antibodies. They are divided into five classes (IGA, IGD, IGE, IGG, IGM) on the basis of structure and biological activity.

**Synonyms:** - Ig - Ig - Immune Globulin - Immunoglobulins - Immunoglobulins / Antibodies - immunoglobulin