- - Innate immune system
- - Adaptive immune system
Innate immunity (natural or native immunity)
Instant
Immediate
Initial response
Induces adaptive immunity
Integrates with adaptive immunity
A
Adaptive immune systemAcquired
Await days = no immediate response
Accurate = specific
Autoregulation
Autoimmunity
The Immune Response
Innate immunity is the first line of defense against infections. Innate immunity is specifically against microbes, while adaptive immunity is against any "foreign" substance (including cancer cells, autoantigens, etc.).
Innate immunity is the oldest mechanism of defense. Adaptive immunity (T and B lymphocytes) appeared in jawed vertebrates (sharks) and is superimposed on innate immunity to improve host defense. In a sense, adaptive immunity is an "add-on" to innate immunity.
Innate Recognition of Pathogens