Immunity

Question 1

Basically, what defines the innate immune system?

Answer 1

It is inborn and operates throughout life

Question 2

What defines the Adaptive immune system?

Answer 2

It changes in response to the pathogens it encounters and is characterised by the development of immunological memory

Question 3

What are cytokines?

Answer 3

Small soluble proteins involved in cell-cell signalling

Question 4

What does autocrine mean?

Answer 4

Acts on cell secreting in

Question 5

What does paracrine mean?

Answer 5

Acts on adjacent cells

Question 6

What does endocrine mean?

Answer 6

Acts on cells and organs at remote sites

Question 7

What are chemokines>

Answer 7

Subgroup of cytokines that recruit phagocytes and cause diapedeses

Question 8

What do monocytes differentiate into in tissues?

Answer 8

Macrophages

Question 9

What is the most abundant cell of the innate immune system?

Answer 9

Neutrophils

Question 10

What cells release Histamine?

Answer 10

Mast cells and Basophils

Question 11

What cell releases Histaminase?

Answer 11

Eosinophils

Question 12

What PRR mediate phagocytosis?

Answer 12

Fc, beta-glucan and complement receptors

Question 13

What PRR’s mediate an inflammaory response?

Answer 13

TLR’s, CLR’s and RLR’s

Question 14

What are the symptoms of inflammation?

Answer 14

swelling, redness, heat, pain and loss of function

Question 15

What are the 3 complement pathways?

Answer 15

Classical, alternative and mannose binding lectin pathway

Question 16

What do all three complement pathways result in?

Answer 16

Formation of the membrane attack complex

Question 17

What complement proteins form the membrane attack complex?

Answer 17

C5b-9

Question 18

Where are complement proteins produced

Answer 18

In the liver

Question 19

Once a dendritic cell has encountered an antigen where does it migrate to?

Answer 19

Paracortex of lymph node

Question 20

What do dendritic cells do in the local lymph node?

Answer 20

They present their antigen to T-cells

Question 21

What are the two different types of T-cell?

Answer 21

Th (CD4+) cell and T cytotoxic (CD8+) cell

Question 22

What do CD4+ cells respond to?

Answer 22

MHC 2+ Ag presentation

Question 23

What do CD8+ cells respond to?

Answer 23

MHC1+Ag presentation

Question 24

What are B-cells activated by>

Answer 24

T helper cells and macrophages presenting antigen

Question 25

What happens when CD4+ Th1 cells are activated?

Answer 25

They proliferate - secreting IL2 (self stimulate) | Secrete IFN-gamma and TNF-alpha

Question 26

What does IFN-gamma do?

Answer 26

Increases ability of macrophages to lyse phagocytosed pathogens

Question 27

What happens when CD8+ cells are activated?

Answer 27

produce cytolytic enzymes which are injected into the cell to trigger apoptosis

Question 28

What happens when CD4+ Th2 cells are activated?

Answer 28

They self stimulate with IL4 which also causes B-cell proliferation

Question 29

What happens when B cells are activated?

Answer 29

They differentiate into effector and memory cells.

Question 30

What are plasma cells?

Answer 30

The effector cells once Bcells have been activated

Question 31

What does humoral immunity involve?

Answer 31

CD4 Th2 cells --> B cells and antibodies

Question 32

What does cellular immunity involve?

Answer 32

CD4 Th1 cells --> macrophages

Question 33

What is affinity maturation?

Answer 33

random mutations in v-region genes - changes to DNA sequence affecting affinity (antigen binding ability)

Question 34

What is class switching?

Answer 34

Recombination of Ig gene segments. Constant region = heavy chains but change in variable region so there is the same antigen specificity

Question 35

What are some of the chemical factors that are involved in vasodilation and increased vascular permeability in inflammation?

Answer 35

Histamine, NO, substanceP, bradykinin, leukotrienes, IL1, TNF, IFN-gamma