Regulation of immunity 1

Question 1

Bullet pointed immune response to invader. super broad

Answer 1

1) Recognition
2) Innate response -> cytokine release; complement activation; inflammation
3) Clearing the pathogen
4) Adaptive immune response -> neutralisation/antibody-mediated clearance; memory

Question 2

Components of the regulatory system

Answer 2

Naturally programmed regulation
Immune cells
Complement, cytokines, and other soluble factors
Innate
Adaptive

Question 3

Complement regulatory proteins

Answer 3

System of soluble membrane-bound complement-regulatory proteins that limit complement activation on host tissues to prevent damage from inadvertent binding and spontaneous activation of complement components

Question 4

Defects in the complement regulatory system

Answer 4

1) Genetically-determined factor 1 deficiency
2) Mutations in MCP/factor 1/factor H
3) SNPs in the factor H gene

Question 5

Genetically-determined factor 1 deficiency

Answer 5

Uncontrolled complement activation leads to rapid deletion of complement proteins; patients suffer repeated bacterial infections

Question 6

Mutations in MCP/factor 1/factor H

Answer 6

the contraction of functional regulatory proteins is reduced and activation leads to a predisposition to atypical haemolytic uremic syndrome, characterised by platelet and RBC damage as well as kidney inflammation

Question 7

SNPs in the factor H gene

Answer 7

linked to age-related macular degeneration, leading cause of of blindness in the elderly in developed countries

Question 8

Regulation - natural killer cells

Answer 8

Highly potent
Cytotoxic granules - perforin, granzyme, etc
Set of activatory and inhibitory receptors
Normal cell -> engages w MHC I and inhibits cytotoxic activity
Abnormal cell -> attacks cells that lack the class I MHC antigen; e.g. virus infected cells, tumour cells

Question 9

Regulation - Macrophage (MQ)

Answer 9

Functions specifically adapted to local environment
Mregs directly inhibit the proliferation of activated T-cells and help with induction of Tregs by producing TGF-beta

Question 10

Tolerance to food antigens

Answer 10

Food proteins induce active form of immunological tolerance in systemic and mucosal immune system, mediated by Tregs producing IL-10 and/or TGF-beta

Question 11

Dendritic cells in the gut

Answer 11

Abundant in the lamina propria
Sample antigens from lumen and surrounding tissue to present then migrate to mesenteric lymph node to present antigen to naive t cells
Encounter develops antigen-specific FoxP3+ Tregs
Primed Tregs leabe tje lymph node and suppress production of inflammatory responses to harmless food antigens

Question 12

Intestinal MQ

Answer 12

Highly phagocytic
Scavenge apoptotic epithelial cells
Produce large amount of IL-10
Unable to migrate from intestine