Immunology lecture 1

Question 1

Over immune system

Answer 1

• Costly
• Well balanced
• Infectious agents spectrum
• Self from non-self

Question 2

Components of immune system

Answer 2

• Myleoid stem cells
• Lymphoid stem cells
• Dendritic cells bridge innate + adaptive systems

Question 3

Innate vs adaptive immune systems

Answer 3

• Innate = 1st line of defence, rapid

- Adaptive = 2nd, slower but specific

Question 4

Major histocompatibility complex

Answer 4

• Genetic locus, 3000kb
• Encodes MHC class I + II
• Similar = receptor for foreign peptide
• Polymorphic

Question 5

MHC class I

Answer 5

• a chain 450kDa, B2 micro globulin
• Membrane-distal (a1 + a2)
• Peptide binding groove (defines groove but degenerate)
• Foreign protein denatured 7-9aa fragment
• All somatic cells have

Question 6

• a chain 450kDa, B2 micro globulin
• Membrane-distal (a1 + a2)
• Peptide binding groove (defines groove but degenerate)
• Foreign protein denatured 7-9aa fragment
• All somatic cells have

Answer 6

1. Proteosome = 700kD, 15-20 enzymes

2. Transporter associated w/ antigen processing (TAP) = translocates small peptides across membrane

Question 7

MHC class II

Answer 7

• Restricted to APCs
• a chain (33kD) and B chain (28kD), each folds to 2 domains
• Have peptide binding groove

Question 8

MHC class 2 endocytic pathway

Answer 8

• Ag matures → late endoscope
• Environment ↑ acidic, degrades protein
• MHCII assembled in ER
• MHCII intersects endocytic pathway at late endosome