Effector-triggered immunity

Effector-triggered immunity (ETI) is a property of the innate immune system. ETI was first identified in plants but has also been identified in animal cells.
The innate immune system is common to all multicellular organisms and forms the first line of defense against pathogens. Infected cells recognize that they are under attack by detecting the pathogen directly through the Pathogen Associated Molecular Patterns (PAMPs) which bind with the Pattern Recognition Receptors (PRR) on the host cells. Host cells also recognize the pathogen through effector-triggered immunity, whereby the host cells are alerted to the pathogen by the associated damage caused by pathogenic toxins or effectors.