immunoglobulin

noun

1. Any of the glycoproteins in blood serum that respond to invasion by foreign antigens and that protect the host by removing pathogens; an antibody.

   “The recent observation that a heat labile human immunoglobulin, IgE , could mediate the release of both histamine and SRS-Aᵐᵒⁿᵏᵉʸ from primate lung slices (Ishizaka et al., 1969), prompted a re-examination of the biologic activity of rat heat labile homocytotropic antibody.”