antiserum /an″tisir′əm/ pl. antisera, antiserums [Gk, anti + L, whey] , the serum of an animal or human containing antibodies against a specific disease, used to confer passive immunity to that disease. Antisera do not provoke the production of antibodies. There are two types of antisera: antitoxin neutralizes the toxin produced by specific bacteria but does not kill the bacteria, and antimicrobial serum acts to destroy bacteria by making them more susceptible to leukocytic action. Polyvalent antiserum acts on more than one antigenic determinant; monovalent antiserum acts on only one. Antibiotic drugs have largely replaced antimicrobial antisera. Caution must always be used in the administration of all antisera, since hepatitis or hypersensitivity reactions can result. Also called immune serum. Compare vaccine.
