Pathology Week 3: Quiz 2: Diseases of the Immune System- Innate Immunity Flashcards
Mediated by cells and proteins that are always present and react to infectious pathogens.
Innate immunity
Innate immunity provides the first line of defense in response to what?
infection
Innate immunity are involved in clearing what products from the body?
damaged cells and tissues
A major reaction of innate immunity
Inflammation
Major component of innate immunity
epithelial barriers
What do epithelial barriers do in innate immunity?
block the entry of microbes
What cells comprise the innate immune system?
- Phagocytes (neutrophils and macrophages)
- Dendritic cells
- NK cells
Express receptors that sense the presence of infectious agents that are released form dead cells.
Cells of innate immunity
What happens when pathogens have evolved to resist innate immunity and protection against these infections requires a more specialized approach?
Adaptive immune system takes over
How do the innate and adaptive immune systems differ: number of substances they can recognize?
Innate: Vast array
Adaptive: Less
How do the innate and adaptive immune systems differ: Response timing
Innate: Rapid
Adaptive: Slow
How do the innate and adaptive immune systems differ: recognition receptors
Innate: germ-line encoded, CD14, mannose and scavenger
Adaptive: initially low affinity
How do the innate and adaptive immune systems differ: Response to recognition of pathogen
Innate: increased cytokines, costimulatory molecules
Adaptive: Gene rearrangement, clonal expression
How do the innate and adaptive immune systems differ: Result of response
Innate: Phagocytosis, antimocrobial activity
Adaptive: T and B cells with receptors encoded, memory
Two lines of defense of innate immunity
- Natural barriers
2. Inflammatory response
What are considered the natural barriers involved in innate immunity?
- Intact skin/epithelial cells
- Simple chemicals
- Mucous membranes/Mucous
- Cilia
- Normal Bacterial Flora
Closely packed cells, multiple layering, continuous shedding of cells, and presence of keratin.
Intact skin as a natural barrier
Create non specific, salty, acidic environment, and antibacterial proteins
Simple chemicals as a natural barrier
GI, respiratory, urogenital tracts
Mucous membranes as a natural barrier
Block and destroy microbes by secreting antimicrobial enzymes, proteins and peptides.
Epithelial cells as a natural barrier
Traps and washes away invaders.
Mucus as a natural barrier