Antigen Presenting

Question 1

Proteins present on the surface of cells.

Answer 1

MHC molecules (Major Histocompatibility Complex )

Question 2

Cells that process and display antigen to T-lymphocytes

Answer 2

APC (Antigen Presenting Cells)

Question 3

T-cells that haven’t come in contact with antigen

Answer 3

‎ساذجة - Naïve T-Lymphocytes •

Question 4

• Additional signals required for T-cells activatio

Answer 4

Co-stimulation and Co-stimulatory signals

Question 5

Clonal expansion

Answer 5

Proliferation (increase in number) of a particular clone of lymphocyte (antigen specific lymphocyte)

Question 6

Proteins released by several types of cells that act on other cells (adjacent –
paracrine, or distant-endocrine) Also called the cell messengers

Answer 6

Cytokines

Question 7

Single lymphocyte that has…….. specificity and its own…….. cells.

Answer 7

antigenic

progeny

Question 8

Organs where lymphocytes mature (primary) or accumulate (secondary)

Answer 8

Lymphoid organs

Question 9

continuous movement of mature lymphocytes from – blood - peripheral lymphoid organs – lymph - blood

Answer 9

• Lymphocyte recirculation

Question 10

continuous movement of mature lymphocytes from –………. - peripheral…………..–………. -………..

Answer 10

blood

lymphoid organs

lymph

blood

Question 11

Clonal proliferation culminates in formation of effector cells / memory cells.

Answer 11

Lymphocyte differentiation

Question 12

the lymphocytes acquire the ability to respond to the antigens (produce immune response)

Answer 12

Maturation

Question 13

Maturation of the lymphocytes happens in the…………… like…….. gland and…………

Answer 13

1- central lymphoid organs.

2- thymus.

3- bone marrow .

Question 14

so the precursors of lymphocytes differentiate into ………. And…….

Answer 14

b lymphocytes precursors and T lymphocytes precursors.

Question 15

When maturation is done the cell then is called………………cell

Answer 15

immunocompetent

Question 16

Once they mature, they inter the……………………., and they keep on circulating the body but they are yet to encounter the antigen therefore they are known as…………….

Answer 16

1- peripheral organs circulation

2- naive lymphocytes

Question 17

When these naive lymphocytes encounter antigens they become activated and differentiated and proliferate and turn into effector cells. Proliferation of lymphocytes after antigen encounter is Known as
differentiation.

Answer 17

Differentiation

Question 18

differentiation : When these naive lymphocytes…,…… antigens they become………… and………….. and proliferate and turn into….,….. cells. Proliferation of lymphocytes

Answer 18

encounter

activated

differentiated

effector

Question 19

Lymphocytes which produce an immune response – antibody producing plasma cells from B-Lymphocytes and Cytotoxic Lymphocytes(CTL) and T-helper cells (TH cells) from T-lymphocytes.

Answer 19

Effector cells

Question 20

Effector cells:
Lymphocytes which produce an immune response – antibody producing ………..from B-Lymphocytes and…………. and……….from T-lymphocytes

Answer 20

plasma cells

Cytotoxic Lymphocytes(CTL)

T-helper cells (TH cells

Question 21

We have distinct lymphocyte clones each for a specific antigen . Since we have thousands of antigens we will also have for each of them ……………….clones.

Answer 21

specific distinct lymphocyte clones.

Question 22

Some lymphocytes differentiates into long lived cells and are responsible for secondary immune response.

Answer 22

Memory cells

Question 23

Total collection of lymphocyte specificities.

Answer 23

Lymphocyte repertoire

Question 24

• Characteristics of adaptive IS

Answer 24

1. Specificity (one lock for one key),
2. Diversity (several locks for different keys),
3. Clonal Expansion,
4. Non-reactivity to Self (no locks for self keys).

Question 25

lymphocyte will only……… it’s sought antigen.

Answer 25

recognize

Question 26

Lymphocytes recognize antigens by………………..

Answer 26

antigen receptors on their surfaces

Question 27

is where the antigen can bind to the lymphocyte.

Answer 27

Antigen receptor

Question 28

peptide antigen bound to and displayed by MHC on APCs- by their T- Cellً Receptor (TCR).

Answer 28

T-lymphocytes recognize

Question 29

Unlike B lymphocytes, T lymphocytes cannot……… the antigen……...

Answer 29

recognize directly

Question 30

the antigen must be………… to the T lymphocytes so they can recognize it

Answer 30

presented

Question 31

The antigen is presented by the help of………………….. The antigen must be presented on the surface of APC and be bound to………. There are exceptions.

Answer 31

APC (antigen presenting cell) MHC

Question 32

These membrane bound antibodies are the receptors on B cells. Recognize antigens by “membrane bound antibodies” on their surface.

Answer 32

B-lymphocytes

Question 33

These membrane bound antibodies are the receptors on B cells. Recognize antigens by “……….."on their surface.

Answer 33

membrane bound antibodies”

Question 34

Recognize a variety of antigen such as

Answer 34

(proteins, polysaccharides, fats and nucleic acids).

Question 35

Why does the immune system require specialized system of antigen presentation for effective immune responses?

Answer 35

a Antigenmayenterthroughanybodysite b.Antigenspecificlymphocytehastocomeincontactwithits homologous antigen (1 in 1 million)-----should locate & react ASAP. c. Different types of antigen may require different responses (antigens in the cytosol and nucleus vs. antigens in the vesicle). d. SometimesISneedstoreacttothesamemicrobeindifferentways depending on its stage of infection.

Question 36

Immune system has developed………….. system for capture and display of antigen.

Answer 36

highly specialized

Question 37

Antigen is presented in the cytosol.

Answer 37

1-Cytosolic antigen .

Question 38

Antigen is presented in the membrane bound the cycle.

Answer 38

2- vesicular antigen:

Question 39

Molecules THAT play a critical role in antigen presentation to T-lymphocytes

Answer 39

MHC

Question 40

Molecules THAT play a critical role in antigen presentation to T-lymphocytes

Answer 40

MHC molecules present on cell surface.  Antigen is bound with MHC molecule on cell surface.  Antigen- MHC complex displayed on surface of APC.  T-Lymphocytes recognize antigen only when it is displayed on surface of APC with MHC.  Each individual’s MHC is unique.  T-Lymphocytes recognize antigen only with MHC of same individual – MHC restriction.  T-Lymphocytes recognize antigen by TCR.

Question 41

 T-Lymphocytes recognize antigen only when it is……………. on surface of APC with MHC

Answer 41

displayed

Question 42

T-Lymphocytes recognize antigen by………………

Answer 42

TCR

Question 43

B cell’s antigen binding receptor binds with the antigen………... It produces antibody.

Answer 43

directly

Question 44

1- T helper cell | Co-stimulator molecule:……..

Answer 44

CD4

Question 45

T cytotoxic cell |  Co-stimulator molecule:……..

Answer 45

CD8

Question 46

Three steps of antigen presentation:

Answer 46

1- Capture 2- Process 3- Present

Question 47

Function of Dendritic cells:

Answer 47

1- Capture antigen 2- Get activated 3- Migrate to L.N ( lymph node) 4- Present antigen to Lymphocytes

Question 48

1-Capture Binding of antigen to the dendritic cells in………... The dendritic cell will ingest the antigen through………………(macrophages will do it through phagocytosis also dendritic cell can make it through……………….).

Answer 48

lectin receptor mediated receptor mediated endocytosis phagocytosis

Question 49

When the dendritic cells will get activate. What will happen to……………………. MHC.

Answer 49

Increase the production

Question 50

``` The antigen has to be migrated to the …………through the …………………  The dendritic cells will express …………..(Chemokine receptor), it will express that after antigen…….. * It will attracted to move towards the lymph node. ```

Answer 50

lymph node chemokine receptor. CCR7 capture

Question 51

Mature dendritic cell presenting antigen ( to ) …………

Answer 51

Naive T cell

Question 52

In the blood the dendritic cells present in the spleen are responsible for….. And why ?

Answer 52

antigen capturing presentation because spleen is the site where blood are filtered.

Question 53

In the mucosal membrane in the skin, the antigen captured is by…………. cells located in the……….

Answer 53

dendritic skin

Question 54

HLA ادينا التفاصيل

Answer 54

(Human Leukocyte Antigens) is a synonym of MHC molecules.

Question 55

Membrane proteins on APCs that display peptide antigen for | recognition by T- lymphocytes.

Answer 55

MHC molecules

Question 56

2 types of MHC molecules –

Answer 56

Class I & II.

Question 57

Both ofthe types of MHC made up of…………… chain but they are……….. different.

Answer 57

2 polypeptid structurally