Innate Immunity Flashcards Preview

MCD- Immunology > Innate Immunity > Flashcards

Flashcards in Innate Immunity Deck (16):
1

Describe innate immunity

From birth
Fast
Recognises patterns
Not specific

2

3 ways of pathogen recognition

PAMPs pathogen structure e.g. peptidoglycan, lipoproteins
DAMPs cell injury e.g. ATP, DNA, collagen
Detect self using NK
- NK use MHC class I receptors
- infected cells downregulate self molecules

3

Characteristics of neutrophils

Multi lobed
Primary granules with enzymes
Secondary granules supply primary

4

Upon infection what do neutrophils do?

Enter tissue
Bind to pathogen
Phagocytosis
Kill

5

What is opsonisation?

Coating of pathogen in either antibodies or complement protein to make phagocytosis easier

6

Characteristic of monocytes

Differentiate into macrophages
Have lysozymes and pattern recognition receptors
Signal infection by releasing cytokines

7

IL 1
IL 6
IL8

Fever
Acute phase protein, acts over long distance
Chemotactic for neutrophils

8

Bacterial septic shock

Release of IL1 and TNF alpha by macrophages drop in both

9

What is a complement ?

Glycoproteins help defence when antigen and antibody bind
Trigger enzyme cascade reaction

10

3 ways complement is activated

Classical = antigen and antibody bind
Lectin is a pattern recognition receptor that binds to carbohydrates on pathogen only
Alternative = activation by surface of pathogen

All activate C3b and form membrane attach complex

11

Function of complements?

Active inflammation response
- degranulation of mast cell
- clearing of antibody antigen complex

12

Mast cells

Secret histamine
Phagocytotic
2 types: mucosal and connective
Activated by anaphylatoxin
Causes vasodilation

13

Describe the local acute inflammation response

Pattern recognition receptor on macrophage binds to PAMP
Macrophages secret alarm cytokines and chemokine
Neutrophils and lymphocytes to find pathogen
Complement activated by pathway
Produce anaphylatoxins
Bind to receptor on mast cell = degranulation
Vasodilation

14

Characteristic of NK

Cytotoxic
Secret interferons
Granulated
Bind to antibody coated cells
Defence against rumours and viruses

15

Missing self recognition

NK recognise MCG class I on cells
They are normal cells
NK inhibitory receptors recognise
Not to be killed

16

Induced self

Cell giving off stress patterns
NK activating receptors regencies
Kill