E-learning

Question 1

What are MHC proteins?

Answer 1

aka HLA proteins in humans

They’re proteins on the cell surface that present foreign antigens and self-antigens to the immune system

Question 2

What do MHC1 do?

Answer 2

Present self-markers on all nucleated cells

Also present endogenous antigens of intracellular pathogens e.g. Viruses

Question 3

What do MHC2 do?

Answer 3

Present exogenous antigens of extracellular pathogens e.g. bacteria on all professional APCs (e.g. Dendritic, macrophage & B lymphocytes)

Question 4

What immune cells recognise MHC1?

Answer 4

CD8 Tc Cells

Nk Cells

Question 5

What immune cells recognise MHC2?

Answer 5

CD4+ Th cells

Question 6

Where do central and peripheral tolerance occur?

Answer 6

Central in bone marrow and thymus

Peripheral in blood (by Treg cells)

Question 7

What are the main 8 physical barriers of the immune system?

Answer 7

• Lysozymes in tears, saliva & sweat
• Mucocillary escalator
• Intact skin
• Intact mucosal membranes
• Acidic pH of stomach
• Alkaline pH of small bowel and rapid change in duodenum
• Normal bowel, vaginal and skin flora
• Urinary Tract Flushing

Question 8

What cells phagocytose?

Answer 8

Macrophages
Basophils
Neutrophils
Monocytes

Question 9

What cells dealt with parasites and other organisms too big for phagocytosis?

Answer 9

Mast Cells
Basophils
Eosinophils