Phagocytes

Question 1

What are phagocytes attracted by?

Answer 1

Stuff on microbes (formylated peptide)

Plasma proteins (complement)

Stuff released by epithelial cells or macrophages exposed to microbes (chemokines like IL-8, MCP)

Stuff released by macrophages and other inflammatory cells NOT exposed to microbes (lipid mediators like LTB4, PAF)

Question 2

M1 Macrophage

Answer 2

Classically activated

Pro-inflammatory

Kills

Question 3

M2 macrophage

Answer 3

Alternatively activated

Anti-inflammatory

Healing

Question 4

Neutrophil arsenal

Answer 4

ROS

Nutrient binding proteins (lactoferrin to sequester iron from fungi!)

Proteases

Lysozymes

Microbicidal peptides (defensins and cathelicidins)

Question 5

How are macrophages activated

Answer 5

INF-gamma released by lymphocytes

TNF-alpha from other macrophages

Note: you block TNF-alpha in rheumatoid arthritis pts to alleviate symptoms and their latent TB shows up because granulomas broken up

Question 6

Eosinophils

Answer 6

SImilar to neutrophils: respiratory burst, phagocytic, 1 day lifespan

Different from neutrophils: bi-lobed, bigger granules, have different granule proteins, kill parasites, show up during allergic response