Immune Diseases

Question 1

What is Digeorge syndrome?

Answer 1

no T cells made b/c thymus doesn’t develop (bubble boy)

Question 2

X linked SCID

Answer 2

absence of T cells b/c IL-7 receptor on lymphoid progenitor isn’t there and therefore can’t become T cells.

Question 3

RAG SCID

Answer 3

VDJ region stitching problem (affects variable region of TCR on T cells and antigen binding region of B cells)

Question 4

XLA disease

Answer 4

B cells don’t develop b/c BTK checkpoint is missing while B cell is developing in the bone marrow (therefore can’t make any antibodies!)

Question 5

Which disease can use IgG infusions to treat? a) Digeorge syndrome b)xlinked scid c) rag skid d) XLA disease

Answer 5

D) XLA disease

Question 6

Clonal deletion of T cells

Answer 6

Central tolerance: T cells that are self are given a signal to do apoptosis

Question 7

Regulatory T cells

Answer 7

Peripheral tolerance: T cells that suppress self reactive B and T cells

Question 8

Receptor editing

Answer 8

central tolerance: B cells that are self reactive will do a gene rearangement in their variable region to become not self reactive

Question 9

Myasthenia Gravis

Answer 9

antibodies bind to receptors on eye muscle cells and don’t allow acetylcholine from nerve cell to bind to muscle receptors

Question 10

Lupus

Answer 10

antibodies bind to DNA and form “immune complexes” that deposit in blood vessels and damage glomulerus of kidneys

Question 11

Type 1 diabetes

Answer 11

T cells attack pancrease cells, which causes a decrease in insulin production

Question 12

Psoriasis

Answer 12

T cells (TH17) release IL17 which causes an immune response that causes neutrophils to damage the skin

Question 13

What is sensitization?

Answer 13

first exposure to allergen. The T helper cells interact with B cells and cause them to start making IgE (from IgG). IgE will bind to receptors on surface of mast cells

Question 14

What do TH2 cells do during initial sensitization?

Answer 14

They release IL4 and IL5, which activate eosinophils

Question 15

2nd exposure to allergen

Answer 15

IgE on mast cells bind to allergen and do cross linking. The mast cell will release TNF, histamines and prostaglandins. Meanwhile the esosinophils release proteases

Question 16

What does histamine and TNF do during the 2nd exposure to a allergen?

Answer 16

TNF causes neutrophils to exit the blood into the tissue. Histamines cause fluid to leak out of blood vessels into the tissue (hives)

Question 17

What is allergy tolerance?

Answer 17

B cells produce IgG4 instead of IgE (these bind to mast cells instead and prevent an immune response)= allergy immunotherapy

Question 18

What happens if a self T cell escapes clonal killing and sees a self antigen?

Answer 18

Peripheral monitoring….
The t cell will get signal 1, but will not get signal 2 from the dendritic cells