Innate Immune system

Question 1

What is the cell to respond to an infection ?

How do they recognise an infection ?

Answer 1

Macrophage

PAMPS

Phagocytosis

Question 2

What happens if the attacking army is too big for the macrophages to deal with alone????

Answer 2

It releases cytokines leading to inflammation.

This recruits more immune cells, including more macrophages, monocytes, and neutrophils.

Question 3

WHen there is an infection and Inflammation occurs, it stimulates macrophages and neutrophils to secrete more cytokines, specifically, a group called Interleukins.

What interlukins are sent where?

Answer 3

• Interleukin 1 is sent to the brain to tell it to produce a fever; this leads to high temperatures that are poorly tolerated by many pathogens. This causes poor appetite and lethargy so the person can conserve more energy to fight the infection.
• Interleukins 6 is sent to the liver to produce acute-phase proteins acting as opsonin.
• Interleukin 8 is released to recruit and activate more neutrophils.
• Interleukin 12 activates natural killer cells.
• TNF (tumour necrosis factor-alpha) is released, which does ALL these effects by itself.

Question 4

In a first expsoure, which pathways of the complement system are triggered by a pathogen ?

Answer 4

• Lectin pathway
• Alternative pathway