immune response

An immune system is a collection of mechanisms within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own healthy cells and tissues in order to function properly. Detection is complicated as pathogens adapt and evolve new ways to successfully infect the host organism.
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Immune response n. An integrated bodily response to an antigen, especially one mediated by lymphocytes and involving recognition of antigens by [more]Immune response - Community and Resources

Noun
1. a bodily defense reaction that recognizes an invading substance (an antigen: such as a virus or fungus or bacteria or transplanted organ) and produces antibodies specific against that antigen
(synonym) immune reaction, immunologic response
(hypernym) reaction, response
(hyponym) anamnestic response, anamnestic reaction
(part-meronym) complement
(classification) fungus

Any reponse by the immune system.

The activity of the immune system against foreign substances (antigens).