CHAPTER 2
Immunologie
Cara Mestdag
KU Leuven
CHAPTER 2
, 1
Inhoudsopgave
, 2
Innate immunity: The first line of defense
Microbial invaders are typically detected and destroyed by the
body's innate immune system within minutes or hours,
independent of antigen-specific lymphocytes.
Innate receptors, encoded by genes inherited from parents,
are inborn and do not require gene rearrangements like those
in the adaptive immune system.
Immunodeficiencies in innate immunity can increase
susceptibility to infections, even with an intact adaptive
immune system.
The infection begins when a pathogen breaches host anatomic
barriers. Immediate defenses involve preformed soluble
molecules, such as enzymes and peptides, capable of killing or
weakening pathogens.
Antimicrobial enzymes like lysozyme digest bacterial cell walls,
while peptides like defensins directly lyse bacterial cell
membranes.
The complement system, a group of plasma proteins, targets
pathogens for lysis and phagocytosis by innate immune cells.
Pattern-Recognition Receptors (PRRs) on innate immune cells
become activated by detecting pathogen-associated molecular
patterns (PAMPs).
Activated innate cells engage effector mechanisms to
eliminate the infection, without generating long-term
immunological memory.
If innate defenses fail, the adaptive immune response is
induced, leading to the expansion of antigen-specific
lymphocytes and the formation of memory cells.
Anatomic barriers, including epithelia and underlying
phagocytes, provide fixed defenses against infection. Chemical
defenses, such as antimicrobial enzymes and peptides, protect
epithelia.
The complement system, along with other circulating
defensive proteins, is part of humoral innate immunity,
derived from the word 'humor' for body fluids.
Inflammation occurs if early defenses fail, involving the
recruitment of new cells and circulating effector molecules.
Immunologie
Cara Mestdag
KU Leuven
CHAPTER 2
, 1
Inhoudsopgave
, 2
Innate immunity: The first line of defense
Microbial invaders are typically detected and destroyed by the
body's innate immune system within minutes or hours,
independent of antigen-specific lymphocytes.
Innate receptors, encoded by genes inherited from parents,
are inborn and do not require gene rearrangements like those
in the adaptive immune system.
Immunodeficiencies in innate immunity can increase
susceptibility to infections, even with an intact adaptive
immune system.
The infection begins when a pathogen breaches host anatomic
barriers. Immediate defenses involve preformed soluble
molecules, such as enzymes and peptides, capable of killing or
weakening pathogens.
Antimicrobial enzymes like lysozyme digest bacterial cell walls,
while peptides like defensins directly lyse bacterial cell
membranes.
The complement system, a group of plasma proteins, targets
pathogens for lysis and phagocytosis by innate immune cells.
Pattern-Recognition Receptors (PRRs) on innate immune cells
become activated by detecting pathogen-associated molecular
patterns (PAMPs).
Activated innate cells engage effector mechanisms to
eliminate the infection, without generating long-term
immunological memory.
If innate defenses fail, the adaptive immune response is
induced, leading to the expansion of antigen-specific
lymphocytes and the formation of memory cells.
Anatomic barriers, including epithelia and underlying
phagocytes, provide fixed defenses against infection. Chemical
defenses, such as antimicrobial enzymes and peptides, protect
epithelia.
The complement system, along with other circulating
defensive proteins, is part of humoral innate immunity,
derived from the word 'humor' for body fluids.
Inflammation occurs if early defenses fail, involving the
recruitment of new cells and circulating effector molecules.
