Diseases

Question 1

What causes RAG SCID

What dz does it allow

Answer 1

No RAG signal=No VDJ and therefore no BCR or TCR

Causes opportunistic infections and rash/blisters

Question 2

What causes DiGeorges

What dz happens

Answer 2

Micro deletion of 22q11(CATCH-22)=no 3 and 4 pharyngeal pouches=no thymus= almost no T Cells
Causes opportunistic infections w/ cardiac defects, low ears and small mouth
Treat with thymus transplant

Question 3

What causes IPEX

WHAT DZ OCCURS

Answer 3

Treg deficit allows for T cells sensing self antigen to replicate (bc of no cd4 cytokine signaling) causes T Cell attack on self (autoimmune)
No B cell effects
X linked FOXP3 disease
- diarrhea, derm issues, thyroiditis, DM

Question 4

What causes Homozygous-lambda-5 deficit

What dz and symptoms occur

Answer 4

No surrogate light chains=no pre-BCR=apoptosis of all B cells @ pre B Cell stage-meaning B cell deficit and no circ AB
Treat with IVIG and AB for specific dz and ffp
Symptoms are bleeding disorders
Autosomal recessive

Question 5

What causes XLA
What dz occurs
What signs and symptoms

Answer 5

XLA is BTK deficient= B cells do not mature past pre B cells
No B cells memory leads to recurrent infections from extra cellular diseases

Question 6

What causes anti-IL-7 AB
What dz occur
What symptoms

Answer 6

IL-7 is required for B cell maturation and it is deficient due to AB against it
- Causes no mature or immature B cells
50% of B cells that make it past prophase live bc of VDJ occurring on one chromosome
Limited Ig or memory

Question 7

What causes Burkitts lymphoma
What dz occurs
What are symptoms

Answer 7

Burkitts lymphoma is from translocation of Ig and MYC genes
Malignancy of plasma/bcells
MYC regulates cell cycle and apoptosis via BCL-2 expression
- overexpression of BCL-2 leads to long lived B cells that acquire malignant mutations

Question 8

What is MYC

how does it work

Answer 8

Regulates apoptosis and cell growth
Facilitates DNA binding and transcription
-causes cells to act as stem cells and not differentiate or die

Question 9

What causes AIRE deficit

What are signs and symptoms

Answer 9

An issue with mTEC gene for AIRE in medulla of thymus
Dz is failure of positive and negative selection causing non-apoptosis of self specific T cells that attack periphery and overwhelm peripheral tolerance
Causes broad spectrum autoimmunity

Question 10

Hyper IgM

Answer 10

X Linked CD40 L deficit

B cells do not respond to T cell presented antigen (causes no VDJ change) and no differentiation in the germinal centers