MoD: Immune Response

Question 1

What are the major components of the Innate Immune response?

Answer 1

• Pattern Recognition Receptors (PRRs)
• Antimicrobial peptide
• Cells (macrophages, dendritic cells, NK cells, neutrophils, eosinophils, mast cells, basophils etc)
• Complement components
• Cytokines

Question 2

What are the 2 groups of Pattern Recognition Receptors?

Answer 2

1) Cell surface (transmembrane) and intracellular receptors (toll-like receptors, C-type lectins)
2) Fluid-phase soluble molecules (Collectins)

Question 3

Cytokine IL1 source and targets?

Answer 3

Source= macrophages, endothelia, epithelia

Targets= endothelia (^ coagulation, ^ inflam.), hepatocytes (^ acute phase proteins), hypothalamus (^fever)

Question 4

Cytokine TNF source and targets?

Answer 4

Source= macrophages, T-lymphocytes

Targets= endothelia (^ coagulation, ^ inflam.), hepatocytes (^acute phase proteins), neutrophils (^activation), hypothalamus (^ fever)

Question 5

Cytokine IL6 source and targets?

Answer 5

Source= macrophages, endothelia, T-lymphocytes

Targets= hepatocytes (^acute phase proteins), B-lymphocytes (^proliferation)

Question 6

What is the 5-stage mechanism of antigen presentation?

Answer 6

• Antigens are internalised
• Broken down to peptides
• Peptides associate with newly synthesised Class 2 molecules and brought to cell surface
• If the peptides are foreign they are recognised by T-helper cells which are then activated
• T-helper cells produce cytokines

Question 7

There are 4 types of Hypersensitivity reaction. Name them.

Answer 7

1- IgE Mediated Reaction (immediate hypersensitivity)
2- Antibody Mediated Cytotoxic Reaction
3- Immune Complex Hypersensitivity
4- Delayed Type Hypersensitivity (cellular)

Question 8

What is immune complex hypersensitivity?

Answer 8

eg) vasculitis, nephritis, arthritis, systemic

There are exogenous/ endogenous antigen triggers: complement activation, C5a attractant for neutrophils, C3b opsonisation