Immunology

Immunology (from immunis, Latin for "exempt") is the study of the organs, cells, and chemical components of the immune system

The immune system of the body is complex and includes both innate and adaptive immune responses

• innate (non-specific) immune response
  • a non-specific (no memory) response to antigen (substance to which the body regards as foreign or potentially harmful)
  • present from birth (1)
  • innate response exists in many lower species, all the way up the evolutionary ladder to humans, and it acts through relatively crude means against large classes of pathogens
• acquired (specific or adaptive) immune response
  • is generally specific to a single organism or to a group of closely related organisms (1)
  • displays a high degree of memory and specificity
  • adaptive response is unique to vertebrates
  • there are two basic mechanisms for acquiring immunity – active and passive (1).

Reference:

• (1) Immunisation Against Infectious Disease - "The Green Book". Chapter 1 Immunity and how vaccines work (Dec 2018)