What does antisera mean?
Antisera is the plural form of antiserum, referring to blood serums that contain antibodies directed against a specific antigen, such as a toxin, virus, or bacterium. Because these antibodies are harvested from the blood of an immunized animal or person rather than produced by the recipient's own immune system, antisera provide what immunologists call passive immunity — immediate but temporary protection. In practice, antisera have long played a dual role: therapeutically, they treat conditions like diphtheria, tetanus, and certain snake envenomations; diagnostically, they identify unknown pathogens or detect specific molecules in laboratory assays. The word appears almost exclusively in formal scientific and medical contexts, written by immunologists, clinicians, and researchers. Historically significant — horse-derived antisera were a mainstay of pre-vaccine medicine — the term remains current today, particularly in discussions of polyclonal and monoclonal antibody preparations.
nounAntisera is the plural of antiserum: blood serums containing specific antibodies against a particular antigen, used to confer passive immunity or in diagnostic testing.
- Plural of antiserum: preparations of blood serum containing antibodies against a specific antigen, used for passive immunization or diagnostics.
"The laboratory stocks antisera against several strains of influenza for rapid diagnostic work."
"Researchers raised antisera in rabbits against the purified protein to use in Western blot assays."
"During the 1920s, diphtheria antisera produced in horses saved countless lives before toxoid vaccines became available."
As 'antisera' is itself a plural, it takes plural agreement; the singular 'antiserum' is used for a single preparation.
"Several antisera were tested before one showed strong reactivity."
Before vaccines were widespread, antisera made from the blood of immunized horses were a frontline treatment for diphtheria and tetanus.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of antisera
The word derives from 'anti-' (Greek, meaning 'against') combined with 'serum', from Latin 'serum', meaning whey or watery fluid — here referring to the clear portion of blood. Antiserum emerged as a scientific coinage in the late nineteenth century alongside the birth of immunology, when Emil von Behring and Shibasaburo Kitasato demonstrated that serum from immunized animals could protect against diphtheria and tetanus. Cognates sharing the Latin root include 'serology' and 'serotonin'.
Related word forms
How antisera is actually used
Antisera is a technical term confined largely to immunology, microbiology, and clinical medicine; it is almost always used in formal scientific writing. Both 'antisera' and 'antiserums' are accepted plurals, though 'antisera' is more traditional in scientific literature.
Easily confused with antisera
Antiserum is the singular form referring to one batch of antibody-containing serum, while antisera refers to more than one such preparation.