random shit to remember (review)

Question 1

looking at titers of IgM and IgG will tell us what

Answer 1

IgM –> primary response

IgG secondary response

usually there is alot more IgG, so if someone has IgM that means they have probably never seen that antigen before

Look at amount of IgM vs. IgG and see where person is in the stage of disease process

Question 2

NK cells

Answer 2

NK cells usually are looking for a receptor (Class I MHC) that inhibits them…

so viruses can down regulate MHC class I to avoid getting killed by the CD8 killer cells

however, NK cells see that the virus infected cell has no receptor to inhibit it and then it kills that cell

Question 3

ADCC

Answer 3

involved in the adaptive immunity

NK cells have receptor for NK Fc.
bind to Fc on the antibody that is bound to some cell that needs to be killed

releases porforins and granzymes

Question 4

pt with history of recurrent bacterial, fungal, and viral infections
23 year old

Answer 4

SCID

decreased RAG (and IL-7)

Question 5

A 4 year old male is being treated for a severe upper and lower respiratory infection. The patient has a history of recurrent pyogenic bacterial infections. Upon serum analysis the patient is found to have low IgA, IgG & IgM. The attending physician suspects an X-linked genetic disorder resulting in deficiencies in proliferation and differentiation of B lymphocytes. The most likely mutation can be found in:

Answer 5

Btk

x-linked agammaglobulinemia

Bruton Tyrosine Kinase (Btk) delivers signal from Pre-BCR for survival of cell

Question 6

what Ig’s cross placenta

Answer 6

IgG

IgM DOES NOT–> so the best test to diagnose acute infection in the neonate would be a parasite specific ELISA for IgM

Question 7

IgG

Answer 7

most abundant in serum
predominant Ab of secondary immune response

4 subclasses- all cross placenta

Question 8

CD markers

Answer 8

Fc receptors for IgG

CD16
CD32
CD64

Question 9

A 37-year-old man comes to the physician with recurrent viral infections. Blood studies show normal levels of circulating lymphocytes and neutrophils. A deficiency in which of the following cytokines would most likely lead to this man’s condition?

Answer 9

IL-2

• growth, survival and differentiation of T lymphocytes
• required for survival of t regs too

Question 10

why is igG highest in serum?

Answer 10

b/c IgG has a higher affinity for antigesn and only things that have high affintiy for antigens are signaled to survive by FDC’s in the lymph node (secondary organs)

Question 11

A new patient presents to your clinic. He has a longstanding history of granulomatosis with polyangiitis. One of the many complications of this illness is chronic lung disease. What would you expect to see in a biopsy of this patient’s lung?

Answer 11

elevated IL-4

Question 12

A 3 y/o boy presents with hematuria. His history is positive for a sore throat 3 weeks ago that was not treated with antibiotics. You diagnose him with post-streptococcal glomerulonephritis. His renal disease is immune complex mediated. Which of the following is cause for his hematuria?

What would you expect to find in his serum?

Answer 12

Complement deposition

decreased complement levels (b/c it is all being used up)

Question 13

CR1 deficiency

Answer 13

cause of increased immune complex deposition and subsequent overactive complement activation

Question 14

HLA-B27

Answer 14

has high correlation with ankylosing spondylitis

Question 15

A deficiency in which receptor would prevent a second signal in the activation of a B cell?

Answer 15

CCR7

activated B cells alter chemokine receptor expression to migrate to t:b interface zone

upregulate CCR7, down regulate CXCR5 and the T cell is the opposite

Question 16

hyper-IgM immunodeficiency

Answer 16

pneumocystis jiroveci (PCP) presenting feature of hyper-IgM immunodeficiency

inability to class switch due to defect in CD40L expression on T cells

CD40 is also expressed on Macrophages/monocytes & DCs
Lack of this signaling leads to impaired handling of opportunist pathogens
CD40 also expressed on platelets & endothelium and epithelial cells during inflammation

Question 17

What is true about the immunoglobulin responsible for atopy?

Answer 17

Sequestered only on cells with FcεRI

Question 18

FCERI is …

Answer 18

a receptor on the mast cell that binds the Fc portion of IgE

Question 19

atopy

Answer 19

atopic /allergies

so having to do with IgE

Question 20

A 34 year old woman has experienced increasing muscular weakness over the past 5 months. This weakness is most pronounced in muscles that are used extensively, such as the levator palpebrae of the eyelids, causing her to have problems with vision by the end of the day. After a night’s sleep, her symptoms have lessened. On physical examination, she is afebrile. No skin rashes are noted. Muscle strength in 5/5 initially, but diminishes with repetitive movement. Which of the following is the most likely mechanism in this patient?

Answer 20

Antibody-mediated dysfunction of NMJ

Question 21

c. diff

Answer 21

gram positive

Question 22

neisseria and pseudomonas

Answer 22

gram negative