Innate immunity & complement Flashcards
List the cells that make up the innate immune system
- Neutrophils
- Eosinophil
- Basophil
- Natural killer cell
- Mast cells
Monocytes and Macrophages and Dendritic cell
List the non-cellular components of the innate immune system
- Complement
- Cytokines
- Lactoferrin
- Acute phase proteins
What is Lactoferrin
- an iron binding protein
- is produced by epithelial cells of mucus & membranes & neutrophils
- is antibacterial
What are acute phase proteins
- produced in liver in response to cytokines
- diagnostic marker of inflammation
Describe the complement system
- 30 plasma proteins
- naturally circulate in the blood
- are activated in response to infection
Describe the main roles of the complement system
- inflammation
- chemotactic agents (recruits neutrophils and macrophages to site of infection)
- Causes cell lysis
- Opsonisation
What is opsonisation
coating of surface area leading to increased phagocytosis
What is cell lysis
causes pore formation in cell membranes and causes death of the cell
What links the innate and adaptive immune system
cytokines
complement system
antigen presenting cells
List the 3 types of complement
- classical pathway
- alternative pathway
- lectin pathway
Which complement pathway is antibody dependent
classical pathway
Where is C3 made
by macrophages in the liver
Describe C3
all 3 complement pathways converge on 3
C3 breaks down naturally into C3a and C3b
What does C3a do
acts as an chemoattractant
increases vasodilation
increases fluid in the tissue and speeds up lymph flow
What does C3b do
binds to microbe surfaces via carbohydrates
bind Factor H on host cells taking C3b out of circulation
