immune response
Meaning of immune response: A properly functioning immune response distinguishes harmful invaders from the body's own tissue, activating defenses that range from rapid to highly specific.
Definition of immune response
An immune response is the coordinated set of actions the immune system takes when it detects something it identifies as foreign or harmful, most often a virus, bacterium, or other pathogen, but sometimes a transplanted tissue, a vaccine component, or, in some conditions, the body's own cells. It involves recognizing the foreign material, generally by identifying specific molecules called antigens on its surface, and then mounting a reaction intended to contain or eliminate it.
An immune response can be broadly divided into an innate response, a fast, general defense present from birth, and an adaptive response, a slower but highly targeted defense that improves with repeated exposure and forms the basis of long term immunity, including immunity built through vaccination.
An immune response that is inappropriately directed against the body's own healthy tissue underlies autoimmune conditions, while an immune response that is insufficient can leave a person more vulnerable to infection.
Used in a sentence
Laboratory testing was used to characterize the patient's immune response following vaccination.
Good to know
An immune response can be protective, as with a typical infection or vaccination, or harmful, as when it is mistakenly directed against the body's own tissue in an autoimmune condition.
Word origin
Where “immune response” comes from
Immune derives from Latin immunis, meaning exempt or free from a burden, and response derives from Latin respondere, meaning to answer back.