Immuno week 1 - Post Lect. Updates

Question 1

T or F: neutrophils present antigens

Answer 1

False

Question 2

What cells have IgE receptors?

Answer 2

• Basophils
• Eosinophils
• Mast Cells

Question 3

What are the first CELLs to act in the innate response?

Answer 3

Neutrophils

Question 4

What cell type is active throughout the ENTIRE immune response?

Answer 4

NK cells, more geared toward viral infections

Question 5

What cell in the acquired immune response has a function similar to NK cells?

Answer 5

CD8 T cells

Question 6

What are the APCs?

Answer 6

B cells
Macrophages
Dendritic Cells

Question 7

Why are antibodies more geared toward an extracellular response?

Answer 7

• Access, antibodies are released into the extracellular environment and must bind the toxin themselves (they don’t use MHC that gives them a sample of the intracellular environment)

Question 8

Why are viral responses more T cell driven?

Answer 8

Cells infected with viruses don’t show PRR’s necessarily, therefore the viral proteins that are there will likely get overlooked by macrophages and neutrophils. T cell receptors can sense this though.

Question 9

Where does antigen presentation take place?

- why?

Answer 9

Takes place in the T-cell zone because this is the area where the highest concentration of T cells exist. If APCs present here then there is a much higher chance of them encountering the appropriate T cell.

Question 10

What function of the immune system is most compromised by loss of the spleen?

Answer 10

• Phagocytosis

Question 11

What would happen in the absence of allelic exclusion?

Answer 11

You would get multiple antibodies for cell and the Avidity of the cell for the epitope would be reduced.

Question 12

What will happen to patients that lack IL-7?

Answer 12

They will have B cells but they will not function

**IL-7 is secreted by the stromal cells and is needed for B cell differentiation

Question 13

Lack of what enzyme needed for development will lead to low B cell count (of all types)?

Answer 13

Low BTK would lead to low B cell count

RAG deficiency would too

Question 14

T or F: after moving into circulation, all activities of B cells are antigen independent

Answer 14

True, somatic recombination is the only antigen independent reaction and it occurs during development

Question 15

What is the use of IgM if it lacks a complement region?

Answer 15

It is used in the complement cascade

Question 16

What determines antigen specificity?

Answer 16

Antigen specificity is determined by Variable region of Heavy and Light Chains

Question 17

T or F: a mutation that leads to inability of the intrachain disulfide bond in the light chain would be reason to switch to the Lambda gene

Answer 17

True, but only if this failed on BOTH kappa’s

Question 18

What is the most devastating affect of AID mutation?

Answer 18

Loss of the ability to switch classes

Question 19

An enzyme is mutated that leads to low numbers of BOTH B and T cells. What could it be?

Answer 19

RAG1/2

Question 20

Why do many self-reactive B cells make it out of the the bone marrow?

Answer 20

The Bone marrow is not completely representative of the proteins that will be encountered in the body

Question 21

What is the most important part of the complement cascade?

Answer 21

C3 opsonization

Question 22

What does C5a do?

Answer 22

Recruits neutrophils

Question 23

What is Terminal Complement?

Answer 23

A term that refers to MAC

Question 24

What does it mean if something can fix complement?

Answer 24

It can kick off the complement cascade (i.e. IgM and to some extent IgG)

Question 25

What is likely to be your biggest problem if you lose the ability of terminal complement?

Answer 25

MAC is really only VITAL against Niessiera infection in which its actually even more important than C3

Question 26

T or F: C-reative protein and Mannos-binding lectin are examples of PRRs

Answer 26

True

Question 27

What is the most important complement protein in capsular detection?

Answer 27

C3b, because it allows for opsonization via macrophages

Question 28

What is the most important control protein in complement?

Answer 28

Factor I

Question 29

What cells are most affected by defects in complement control?

Answer 29

Erythrocytes, they will be eliminated because they will bind so much stuff that has C3

Question 30

What cause HANE?

Answer 30

no C1INH

**would lead to low serum C2 and C4

Question 31

Why is low MHC class I a marker of a cell that needs to be killed?

Answer 31

Low MHC class I is an indication that a virus has hi-jacked the cell

**Note MIC will eventually get recycled off too

Question 32

T or F: NK cells alone can clear a viral infection

Answer 32

False

Question 33

T or F: some defensins are seceted while some are naturally present

Answer 33

True

Question 34

When do complement proteins get synthesized?

Answer 34

always!!

Question 35

What are two important chemotractic factors for neutrophils?

Answer 35

IL-8 and C5a

Question 36

What process allows macrophages, dentritic cells, etc. to get to 2˚ lymph tissue?

Answer 36

Inflammation

Question 37

T or F: platelets prevent dissemination.

Answer 37

True

Question 38

Where in/on the cell will you find RIG and NOD?

Answer 38

in the cytoplasm

Question 39

What causes IL-8 to be release?

Answer 39

Release of IL-6 by macrophages

Question 40

What dual purpose does an increased temperature serve?

Answer 40

• Better immune response

- Kills bacteria

Question 41

What do Ig do NK cells recognize?

Answer 41

IgG1 and IgG3 (might want to verify this)

Question 42

When does the acute phase response occur?

Answer 42

When there’s bacteria in the bloodstream

Question 43

Where are Toll-like receptors found in/on the cell?

Answer 43

In the cytoplasmic membrane

Question 44

Whats the purpose of have 3 types of receptors on macrophages (TLR, RIG, NOD)?

Answer 44

TLR - located on the membrane so if its activated then the cell knows its dealing with an extracellular pathogen

NOD, for example, is on the inside leading to signaling that there is an intracellular pathogen

Question 45

What does TLR 5 recognize?

Answer 45

Flagellin