immunosuppression & immunodeficiency

Question 1

What expressions are impt in the generation of BCR and TCR?

If there is deficiency in these enzymes, are B cells and T cells gg to generate?

Answer 1

RAG and TdT expression

NO!!

Question 2

What are the keys to T cell proliferation?

Answer 2

IL-2/IL-2R

Question 3

CD20 is only expressed on

Answer 3

B cells

Question 4

Corticosteroids (immunosuppressants) MOA

Answer 4

inhibit inflammatory and cytokine production and activities

Question 5

Methotrexate/ azathioprine (chemo drugs) MOA

Answer 5

inhibit lymphocyte growth

Question 6

Rituximab (anti-CD-20), Belimumab (anti-BAFF)

(B cell-specific drugs) MOA

Answer 6

• deplete b cells

- inhibit B cell growth

Question 7

_______ is used to prevent rejection reactions. They reduce T cell response to IL-2

Answer 7

Rapamycin

Question 8

Cyclosporine A inhibits _____ proliferation. They are used when milder immunosuppressants such as ______ have failed.

Answer 8

T cell;

steroids

Question 9

Cyclophosphamide (alkylating agents) inhibit cell growth by ___________. It adds an alkyl group to the guanine in DNA to break DNA strands.

Answer 9

interfering with DNA replication

Question 10

If Btk is deficient, what will happen?

Answer 10

disrupts the AP-1 pathway of BCR signalling;

thus lack of B cells and antibodies

Question 11

If adenosine deaminase (ADA) / purine nucleotide phosphorylase (PNP) is deficient, what will happen?

Answer 11

can generate toxic adenosine metabolites causing loss of T/B cells and function;
can affect the differentiation of stem cells to T/B cells

Question 12

____ deficiency: disrupts IL-2R, IL-4R, IL-7R, IL-9R, IL-15R, IL-21R ________.

Answer 12

Yc,

signalling

Question 13

Loss of IL-7R signalling alone disrupts __________. This causes _______

Answer 13

T/B cell generation from lymphoid precursors;

causes SCID

Question 14

____ deficiency increases gut infections

Answer 14

IgA

Question 15

B cell deficiency leads to mutations in _____, increases _____________

Answer 15

CD40L;

increases susceptibility to infection, cancer & autoimmunity

Question 16

____ deficiency increases infection and cancer

Answer 16

CD4

Question 17

SCID (Severe combined immunodeficiency) – lack of _____ cells

Answer 17

T & B cells

Question 18

DiGeorge syndrome:

• no ______
• complete or partial lack of ___ and ___ cells
• loss of ______ & _______ immunity

Answer 18

• no thymus
• complete or partial lack of CD4 and CD8 T cells
• loss of humoral & cellular immunity

Question 19

DiGeorge syndrome: can it be recurrent?

Answer 19

yes

Question 20

SCID: loss of what cells?

Answer 20

T cells, B cells or nK cells

Question 21

Can vaccintation with live attenuated vacines be fatal?

Answer 21

Yes

Question 22

X-linked hyper Ig-M syndrome:

defects in _____________ and _________

Answer 22

helper T cell-dependent B cell and

macrophage activation

Question 23

X-linked hyper Ig-M syndrome:

mechanism of defect?

Answer 23

mutation in CD40 ligand

Question 24

Defective class II MHC exp (the bare lymphocyte syndrome):
lack of class II exp and impaired \_\_\_\_ cell development and activation

Answer 24

CD4+ T cell

Question 25

Defective class II MHC exp (the bare lymphocyte syndrome): mechanism of defect?

Answer 25

mutation in genes encoding transcription factors required for class II MHC gene exp

Question 26

TAP deficiency: lack of class __ MHC molecule exp, decreased no. of _____ cells; susceptibility to _________

Answer 26

lack of class I MHC molecule exp, decreased no. of CD8+ T cells; susceptibility to bacterial infections

Question 27

TAP deficiency: mechanism of defect?

Answer 27

mutation in the TAP genes preventing peptide loading of class I MHC molecules

Question 28

Bare lymphocyte syndrome:

• MHC II deficiency caused by failure to _________
• MHC I deficiency due to failure to ______________
• loss of T cell function

Answer 28

1. switch on MHC genes

2. process antigens for MHC I (eg. lack of TAP)

Question 29

Hyper-IgM syndrome:

• no _____, no germinal centre
• no ____ class switch to ________
• increased susceptibility to infections

Answer 29

• no CD40L

- no IgM class switch to IgA, IgG, & IgE

Question 30

X-linked hyper Ig-M syndrome impairs _______ functions as well

Answer 30

macrophage

Question 31

______ is the most common cause of immunodeficiency worldwide.
It is associated with a significant impairment of ____________, _______ function, _______ system, secretory ____ and ______ production.

Answer 31

Malnutrition

It is associated with a significant impairment of cell-mediated immunity, phagocyte function, complement system, secretory IgA and cytokine production.

Question 32

HIV: retroviruses have an enzyme called ___________ that gives them unique property of __________ into host cell DNA

Answer 32

reverse transcriptase;

transcribing RNA

Question 33

HIV infects ___ cells

Answer 33

CD4 T cells

Question 34

AIDS: infects CD4 T cells and also ______, _____ and _____ using CD4 and ______ to enter cells

Answer 34

macrophages, monocytes and dendritic cells using CD4 and chemokine receptor 5 (CCR5)

Question 35

Treatment for AIDS

Answer 35

anti-retroviral drugs like Abacavir, Gancyclovir that inhibit viral replication