cells and tissues of the adaptive immune system

Question 1

primary lymphoid organs

Answer 1

thymus and bone marrow

Question 2

secondary lymphoid organs

Answer 2

spleen, lymph nodes, and mucosa-associated lymphoid tissue

Question 3

lymphoid progenitor cells give rise to

Answer 3

B lymphocytes, T lymphocytes, and Natural Killer cells

Question 4

CD stand for

Answer 4

cluster of differentiation and indicates a defined subset of cellular surface markers that identify cell type and stage of differentiation

Question 5

lymphoid stem cells during prenatal period are found

Answer 5

in the fetal liver because bone marrow hasn’t developed yet, from here, stem cells generate precursor cells and send them into the tissues

Question 6

all blood cells develop from common

Answer 6

CD34+ pluripotent stem cells

Question 7

starting from 13th week of gestation, some stem cells migrate to the

Answer 7

bone marrow

Question 8

in the bone marrow, stem cells produce

Answer 8

lymphoid progenitor cells which gives rise to B cell progenitors and T cell progenitors

Question 9

B cells are generated in the

Answer 9

bone marrow from B cell progenitor

Question 10

T cells are generated in the

Answer 10

thymus from T cell progenitor cells which migrate from the bone marrow into the thymus

Question 11

antigen-specific receptors are localized on the surface of

Answer 11

T and B cells

Question 12

the structure of antigen-specific receptors varies from one cell to another but they are all

Answer 12

identical on a single cell

Question 13

naive lymphocytes

Answer 13

B and T cells that haven’t encountered their antigens; typically die after 1-3 months

Question 14

the thymus gland is located in the mediastinum of the thoracic cavity ____ and ____ to the heart and ____ to the sternum

Answer 14

anterior

superior

posterior

Question 15

when is the thymus at its largest and most acvtive

Answer 15

during the neonatal and pre-adolescent periods;

later the thymus disappears and is replaced by fat

Question 16

each T cell has receptors specific for only one antigen that are generated by

Answer 16

gene rearrangement from multiple, inherited germline genes

Question 17

T cells which are highly . reactive with self-antigens are deleted by

Answer 17

apoptosis

Question 18

T helper cells

Answer 18

express CD4 and provide help for B cell growth and differentiation (T regulatory cells are a subtype of T helper cells)

Question 19

cytotoxic T lymphocytes (CTLs)

Answer 19

express CD8 and recognize and kill virus-infected cells

Question 20

functionally mature T cells then migrate

Answer 20

to secondary lymphoid tissues to mediate protection

Question 21

T cells make contacts with

Answer 21

specialized epithelial cells, dendritic cells and macrophages in the thymus;

these cell-to-cell interactions provide mechanisms for the selection and differentiation of T cells useful to the immune system

Question 22

cytokines produced by the stromal cell play an important role in

Answer 22

T cell development

Question 23

generated naive T cells leave the thymus and are maintained

Answer 23

in the periphery without proliferating

Question 24

thymoma

Answer 24

usually a slow-growing tumor that typically start in thymic epithelial cells; usually does not spread beyond the thymus gland

Question 25

thymic carcinoma

Answer 25

less common but more aggressive cancer of thymic epithelial cells; generally more difficult to treat because it spreads quickly to other areas of the body

Question 26

most thymomas/thymic carcinomas are diagnosed between _____ and ____ years of age when the thymus does not produce naive T cells

Answer 26

40 60 so they are very rare

Question 27

B cells are produced in the

Answer 27

bone marrow during the lifespan

Question 28

bone marrow

Answer 28

soft, sponge-like tissue in the center of most bone

Question 29

bone marrow produces

Answer 29

white blood cells, red blood cells, and platelets

Question 30

at birth all bone marrow is

Answer 30

red

Question 31

during puberty, red marrow increasingly converts to

Answer 31

yellow marrow

Question 32

in adult, around half of the bone marrow is ____ and half is ____

Answer 32

red yellow

Question 33

before birth, differentiation into B cells occurs within the ____ and then in the ____ after birth

Answer 33

fetal liver bone marrow

Question 34

the development of B cells involves cell-to-cell contacts with ____ and ____

Answer 34

stromal cells and cytoknes

Question 35

many different B cells are generated, each with a unique ____ for particular antigen

Answer 35

specificity

Question 36

B cells which react with self-antigens are

Answer 36

eliminated by apoptosis

Question 37

lifetime production of B lymphocytes occurs

Answer 37

in the bone marrow

Question 38

leukaemias

Answer 38

malignant diseases of the bone marrow and occur during hematopoietic development of either lymphoid or myeloid lineages. the overgrowth of of immature blood cells leads to a shortage of normal white blood cells (leading to increased risk of infections), red blood cells (leading to anemia), and platelets (leading to bruising)

Question 39

myeloproliferative disorders

Answer 39

related to leukaemias in that they are characterized by the overproduction of one type of blood cell and in some cases develop into leukaemias. the most common causes of death were infection, cardiovascular disease, cerebrovascular disease, hemorrhage or thrombosis.

Question 40

multiple myeloma

Answer 40

malignancy of plasma cells. the abnormal plasma cells produce proteins that impair the development of normal blood cells causing anemia (reduced numbers of RBCs) and leukopenia (reduced number of WBCs). infection is a major complication and a leading cause of death in patients with MM.

Question 41

lymphoma

Answer 41

a cancer that develops in circulating blood lymphocytes after their production in the bone marrow. at the late stage, lymphomas can spread to the bone marrow. patients with lymphomas have an increased risk of infectious diseases.

Question 42

lymphocytes develop from bone marrow stem cells and then mature in the primary lymphoid organs: B cells- in the ____ T cells- in the ____

Answer 42

bone marrow thymus

Question 43

mature lymphocytes circulate through the blood to ____

Answer 43

secondary lymphoid organs (lymph nodes, spleen, and regional lymphoid tissues such as mucosa-associated lymphoid tissues)

Question 44

antigens are captured from a site of infection and transported to the ____ where they are recognized by naive B and T cells and immune responses are initiated

Answer 44

draining lymph node

Question 45

lymphocytes continuously circulate searching for their antigens in various parts of the body except

Answer 45

eye, brain, and testicles

Question 46

in search of foreign antigens, lymphocytes enter the secondary lymphoid organs (lymph nodes) via a specialized endothelium of the postcapillary venules called

Answer 46

High Endothelium Venules (HEV)

Question 47

cells of High Endothelium Venules (HEV) are much

Answer 47

higher than normal endothelial cells (bigger?) and they express high levels of adhesion molecules that serve as "homing" receptors for lymphocytes

Question 48

Blood T and B lymphocytes transmigrate through HEV into the lymph nodes by mechanism of ____ and are navigated in the tissue by chemokines produced by stromal cells

Answer 48

diapedesis

Question 49

lymphocytes may be activated by foreign antigens in lymph nodes, if not they are still

Answer 49

naive and return to the blood by lymphatic drainage

Question 50

naive lymphocytes reenter the circulation via

Answer 50

efferent lymph vessels that merge into the thoracic duct

Question 51

naive B cells migrate into the _____ where they look for and respond to _____

Answer 51

secondary lymphoid tissues soluble foreign antigens

Question 52

antigen-activated B cells proliferate and mature into

Answer 52

plasma cells or memory cells

Question 53

plasma cells are terminally differentiated B cells which produce and secrete

Answer 53

large amounts of antibodies

Question 54

where do antigen-activated B cells produce antibodies against microbes in the blood?

Answer 54

in the spleen

Question 55

the spleen participates in immune responses against many types of

Answer 55

blood-born pathogens

Question 56

t-cell zone in spleen

Answer 56

located centrally (also called the periarteriolar lymphoid sheath or PALS)

Question 57

b-cell zone in spleen

Answer 57

distributed around the T zone in tightly packed follicles

Question 58

plasma cells are rarely found in the peripheral blood, but they comprise from 0.2% to 2.8% of the ______ white cell count

Answer 58

bone marrow

Question 59

in search of foreign antigens, naive T cells migrate into

Answer 59

secondary lymphoid organs such as lymph nodes

Question 60

T cells which have been activated by antigens differentiate into

Answer 60

effector or memory T cells

Question 61

some effector and memory T cells migrate back into the

Answer 61

peripheral sites of infection

Question 62

some activated and differentiated T cells remain in the lymph nodes and help _____

Answer 62

antigen-activated B cells to become an antibody factory plasma cell

Question 63

naive B and T cells enter the lymph nodes through an artery leaving the circulation by moving across the

Answer 63

HEV

Question 64

B and T cells migrate to different zones of the lymph node directed by

Answer 64

chemokines that are produced in these areas by stromal cells

Question 65

dendritic cells pick up antigens from the sites of antigen entry and enter through

Answer 65

afferent lymphatic vessels

Question 66

dendritic cells migrate to the ____ areas of the lymph node

Answer 66

T cell-rich

Question 67

in the absence of antigen stimulation, follicles are composed of small naive B cells and/or recirculating memory B cells and called

Answer 67

primary follicles

Question 68

with antigen stimulation, B cells proliferate and differentiate converting the primary follicle into a ____ or ____

Answer 68

secondary follicle germinal center

Question 69

germinal centers were described more than 125 years ago as compartments that contained

Answer 69

mitotic B cells

Question 70

antigen-presenting cells are cells that

Answer 70

capture, process, and display antigens to T lymphocytes and provide signals that stimulate the proliferation and differentiation of the lymphocytes

Question 71

what 3 cells can serve as antigen-presenting cells

Answer 71

dendritic cells, macrophages, and activated B cells

Question 72

only dendritic cells can activate

Answer 72

naive T cells in the lymph nodes

Question 73

macrophages and B cells can present antigens only for

Answer 73

activated T cells but not naive T cells

Question 74

dendritic cells and macrophages are cells of ____; thus they provide an link between

Answer 74

innate immunity innate and adaptive immunity

Question 75

pre-classical dendritic cells gives rise to

Answer 75

classical DCs

Question 76

plasmacytoid DC gives rise to

Answer 76

plasmacytoid DCs

Question 77

monocytes give rise to

Answer 77

inflammatory DCs

Question 78

what gives rise to Langerhans cells?

Answer 78

fetal hemapoietic organs (yolk sac, liver) (hematopoetic stem cell --> embryonic tissue precursor --> Langerhans cells

Question 79

DCs are part of ____ lineage

Answer 79

myeloid

Question 80

DCs can be broadly divided into:

Answer 80

classical DCs, myeloid DCs, and plasmacytoid DCs

Question 81

myeloid DCs (mDC) are derived from

Answer 81

monocytes

Question 82

classical DCs, plasmacytoid DCs (pDC), and Langerhan's cells in epidermis of the skin, develop directly from

Answer 82

stem cells

Question 83

to acquire antigens, DCs use

Answer 83

receptor-mediated endocytosis and pinocytosis

Question 84

DCs express receptors that recognize antigens typcially made by

Answer 84

microbes and not mammalian cells

Question 85

activated DCs secrete

Answer 85

cytokines

Question 86

classical DCs reside in

Answer 86

skin, mucosa, and organ parenchyma

Question 87

upon activation by microbes, classical DCs migrate to

Answer 87

lymph nodes where they display microbial protein antigens to T lymphocytes

Question 88

plasmacytoid DCs are early cellular responders to

Answer 88

viral infection

Question 89

plasmacytoid DCs recognize

Answer 89

nucleic acids of intracellular viruses and produce soluble interferons (aka IFN-alpha/beta)

Question 90

IFN-alpha/beta have potent

Answer 90

antiviral activities