front 1 A naive lymphocyte first recognizes its
specific antigen and begins adaptive immune
activation. Where does this recognition phase occur? | back 1 B. Secondary lymphoid organs |
front 2 Which set contains only secondary lymphoid organs?
| back 2 D. Lymph nodes, spleen, MALT |
front 3 Which organs are classified as primary lymphoid organs?
| back 3 A. Bone marrow and thymus |
front 4 A patient has impaired lymphoid follicle formation.
Which immune structures would most directly share this
abnormality? | back 4 C. Secondary lymphoid organs |
front 5 The common anatomical structure
shared by secondary lymphoid organs is which of the
following? | back 5 B. Lymphoid follicles |
front 6
Lymphoid follicles begin as loose
networks of which cell type? | back 6 D. Follicular dendritic cells |
front 7
Early lymphoid follicles form in regions
especially rich in which lymphocyte
population? | back 7 A. B cells |
front 8
Follicular dendritic cells are already present by
which developmental period? | back 8 C. Second trimester |
front 9 Which cell type displays antigen primarily
to B cells?
| back 9 B. Follicular dendritic cells |
front 10 Which cell type presents antigen primarily to
T cells?
| back 10 B. Conventional dendritic APCs |
front 11 A follicular dendritic cell binds
antigen coated with complement
fragments. Which receptor function explains this? | back 11 B. Complement fragment binding |
front 12 A follicular dendritic cell bind
complement-opsonized antigen because they express
receptors for which material? | back 12 C. Complement fragments |
front 13 A follicular dendritic cell holds many
antigen molecules very close together. What B-cell event
does this promote? | back 13 C. BCR crosslinking |
front 14
Follicular dendritic cells can also bind
immune complexes using receptors for which antibody
region? | back 14 D. Fc region |
front 15 A follicular dendritic cell attracts and activates B
cells, leading to intense B-cell proliferation. Over
time, this active follicle becomes what? | back 15 B. Germinal center |
front 16 A germinal center is best described as which structure? | back 16 A. Active secondary lymphoid follicle |
front 17 Before adaptive immunity responds effectively to infection, which
system must first detect danger? | back 17 C. Innate system |
front 18
B cells proliferating in germinal centers become
fragile. Which cells rescue them from apoptosis?
| back 18 A. Helper T cells |
front 19 Which secondary lymphoid organ lacks high
endothelial venules? | back 19 D. Spleen |
front 20 High endothelial venules serve primarily as a
doorway for which cells? | back 20 B. B and T cells |
front 21 High endothelial venules allow lymphocytes to enter secondary
lymphoid organs from which compartment? | back 21 A. Blood |
front 22
High endothelial venules are regions within
which vessel type?
| back 22 C. Venule |
front 23 In a lymph node, high endothelial venules are located in which
region? | back 23 C. Paracortex |
front 24 In a lymph node, B cells mainly
accumulate in which area? | back 24 B. Cortex |
front 25 In a lymph node, T cells mainly accumulate in which
area? | back 25 A. Paracortex |
front 26
Conventional dendritic cells mainly accumulate in
which lymph-node region? | back 26 C. Paracortex |
front 27
Follicular dendritic cells are mainly located in
which lymph-node region? | back 27 B. Cortex |
front 28 In lymph nodes, the B-cell area correlates with
which dendritic cell location?
| back 28 B. FDCs in cortex |
front 29 In lymph nodes, the T-cell area correlates with
which dendritic cell location?
| back 29 C. Conventional DCs in paracortex |
front 30
Lymph-node sinus walls are carpeted
with which immune cells?
| back 30 B. Macrophages |
front 31
Movement of immune cells within secondary lymphoid
organs is coordinated by which signal type? | back 31 A. Chemokines |
front 32 Chemokines are best described as which type of cytokine? | back 32 B. Chemoattractive cytokines |
front 33
Follicular dendritic cells produce which
chemokine to attract naive B cells?
| back 33 D. CXCL13 |
front 34 After a B cell finds its cognate antigen, what
happens to its CXCL13 receptor expression?
| back 34 C. It downregulates |
front 35 After recognizing cognate antigen, an
activated B cell upregulates which
chemokine receptor?
| back 35 B. CCR7 |
front 36
CCR7 expression helps activated B cells
migrate toward which region? | back 36 D. Cortex-paracortex border |
front 37 The cortex-paracortex border is important because it allows meeting
between which cells? | back 37 A. B cells and T cells |
front 38 Activated helper T cells downregulate signals keeping them in which
region? | back 38 B. Paracortex |
front 39 Activated helper T cells upregulate which receptor to meet activated
B cells? | back 39 C. CXCR5 |
front 40 CXCR5 expression helps helper T cells congregate with activated B
cells at which site? | back 40 B. Follicle border |
front 41 B cells require help from activated helper T cells. Activated helper
T cells also require help from which cells? | back 41 A. Activated B cells |
front 42 The reciprocal help between activated B cells and activated Th cells
occurs through what mechanism? | back 42 A. Cell-cell contact |
front 43 Which B-cell surface protein binds
CD28 on helper T cells?
| back 43 C. B7 |
front 44 Which B-cell surface protein binds
ICOS on helper T cells?
| back 44 B. ICOSL |
front 45 Which helper T-cell protein binds
B7 on the activated B-cell surface?
| back 45 B. CD28 |
front 46 Which helper T-cell protein binds
ICOSL on the activated B-cell surface?
| back 46 D. ICOS |
front 47 A defect prevents activated B cells from interacting
with Th-cell CD28. Which B-cell molecule is most
likely defective? | back 47 A. B7 |
front 48 A defect prevents activated B cells from interacting
with Th-cell ICOS. Which B-cell molecule is
most likely defective? | back 48 B. ICOSL |
front 49 A patient has impaired complement deposition on
antigen. Which FDC function would be most directly reduced? | back 49 A. Binding opsonized antigen |
front 50 Which statement best captures secondary lymphoid organ function?
| back 50 C. They support antigen recognition |
front 51 At the follicle border, an activated Th cell directly helps an
activated B cell through which ligand-receptor pair? | back 51 C. CD40L–CD40 |
front 52 During the B-cell/Th-cell “dance,” which molecule is provided
by the helper T cell?
| back 52 A. CD40L |
front 53 During the B-cell/Th-cell “dance,” which molecule is found on
the B-cell surface and binds CD40L?
| back 53 D. CD40 |
front 54
Activated B cells provide which material to
help helper T cells mature?
| back 54 B. Antigen, B7, ICOSL |
front 55 A helper T cell becomes fully mature at the follicular border after
contact with an activated B cell. What is it now called? | back 55 C. Tfh cell |
front 56
Follicular helper T cells are licensed to
rescue which fragile cell population?
| back 56 A. Germinal-center B cells |
front 57
A germinal-center B cell receives Tfh
help and avoids apoptosis. Which later
processes can Tfh cells support? | back 57 B. Class switching and hypermutation |
front 58 During affinity maturation, B cells with higher-affinity receptors
gain an advantage by doing what? | back 58 B. Plucking more antigen |
front 59 Higher-affinity B cells present more antigen to Tfh cells using which
molecule? | back 59 A. Class II MHC |
front 60 In germinal centers, greater antigen presentation by high-affinity B
cells causes what outcome? | back 60 C. More Tfh help |
front 61 Somatic hypermutation selects higher-affinity B cells because these
cells receive more help from which cells? | back 61 B. Tfh cells |
front 62 A killer T cell recognizes cognate antigen
presented by dendritic cells in a lymph node. Where does
activation occur? | back 62 D. Paracortex |
front 63 A lymph node draining an infected
wound becomes enlarged. Which process
contributes most directly? | back 63 A. Lymphocyte proliferation |
front 64 In infected draining lymph nodes,
medullary sinuses may become
clogged by which cells? | back 64 C. Macrophages |
front 65
Peyer patches are examples of which lymphoid
tissue? | back 65 D. MALT |
front 66 Unlike lymph nodes, Peyer patches
lack which structure? | back 66 B. Incoming lymphatics |
front 67
Peyer patches still contain which drainage
structure? | back 67 A. Outgoing lymphatics |
front 68
Peyer patches are topped by which
specialized epithelial cells?
| back 68 D. M cells |
front 69
M cells over Peyer patches are not coated with which
structures? | back 69 C. Mucus and villi |
front 70 M cells sample material from which location? | back 70 B. Intestinal lumen |
front 71 M cells transport sampled intestinal material into which site? | back 71 D. Underlying tissues |
front 72 The spleen primarily functions as what type of filter? | back 72 A. Blood filter |
front 73 Approximately what fraction of cardiac output enters the
spleen? | back 73 C. 5% |
front 74 The spleen screens circulating blood approximately every how
long? | back 74 B. 30 minutes |
front 75 Compared with lymph nodes and Peyer patches,
the spleen is less selective because everything
enters from where? | back 75 A. Blood |
front 76 Which organs are selective about where B/T cells and antigens
enter? | back 76 D. Lymph nodes and Peyer patches |
front 77 In the spleen, T cells are temporarily
retained in which region? | back 77 C. PALS |
front 78 In the spleen, B cells are found
between which structures? | back 78 B. PALS and marginal sinuses |
front 79 The periarteriolar lymphocyte sheath mainly retains
which cells? | back 79 A. T cells |
front 80 The spleen lacks lymphatics
to transport dendritic cells from tissues. How does
it compensate? | back 80 D. Uses resident dendritic cells |
front 81 In the spleen, resident dendritic
cells take up antigens from
invaders located where?
| back 81 C. Blood |
front 82 Which organ is a main site where B cells can activate without Th-cell
assistance? | back 82 B. Spleen |
front 83 B cells that can activate without Th-cell help in the spleen are
called what? | back 83 D. Marginal-zone B cells |
front 84 Marginal-zone B cells are stationed where they contact blood entering
the spleen. Where is this? | back 84 A. Marginal sinuses |
front 85 Secondary lymphoid organs are strategically positioned to intercept
which threat? | back 85 C. Invaders entering the body |
front 86 Secondary lymphoid organs provide environments that mobilize weapons
appropriate to what? | back 86 B. Likely invading organisms |
front 87 The most important function of secondary lymphoid
organs is bringing together which
cells? | back 87 D. Lymphocytes and APCs |
front 88 Bringing lymphocytes and APCs
together increases the probability of
activating which immune system? | back 88 A. Adaptive immune system |
front 89 The process of B and T cells moving to specific locations is called
what? | back 89 B. Lymphocyte trafficking |
front 90 Virgin and experienced lymphocytes differ mainly in which
feature? | back 90 C. Traffic patterns |
front 91
Virgin T cells use which molecule to
enter lymph nodes through HEVs?
| back 91 A. L-selectin |
front 92
L-selectin on virgin T cells binds which
ligand on lymph-node HEVs? | back 92 D. GlyCAM-1 |
front 93
Virgin T cells use which integrin
to enter Peyer patches and intestinal lymph nodes?
| back 93 B. α4β7 |
front 94 α4β7 on virgin T cells binds which ligand on intestinal HEVs? | back 94 C. MadCAM-1 |
front 95 MadCAM-1 is expressed on HEVs in which sites? | back 95 A. Peyer patches, intestinal nodes |
front 96
Virgin T cells circulate through
blood and lymph, spending about how
long per loop?
| back 96 A. 1 day |
front 97 If a virgin T cell does not find cognate
antigen, it dies after approximately how
long? | back 97 D. 6 weeks |
front 98 A virgin T cell failing to find cognate antigen
eventually dies by what mechanism? | back 98 C. Apoptosis |
front 99
Experienced T cells that have found cognate
antigen have their travel passports become what?
| back 99 D. Restricted |
front 100 Experienced T cells express adhesion molecules based on what
location? | back 100 A. Where they activated |
front 101 A T cell activated in a Peyer patch will increase which adhesion
molecule? | back 101 C. α4β7 |
front 102
Increased α4β7 on Peyer-patch-activated T
cells helps them do what? | back 102 A. Return to mucosal sites |
front 103 Experienced T cells also carry “combat passports” that help them
enter what sites? | back 103 B. Sites of infection |
front 104
Experienced mucosa-activated T cells
express which integrin? | back 104 D. αEβ7 |
front 105 αEβ7 helps experienced mucosal T cells enter which tissue
environment? | back 105 A. Inflamed mucosa |
front 106 A defect in CD40L expression on activated Th cells would most
directly impair which interaction? | back 106 A. B-cell CD40 activation |
front 107 A B cell fails to provide B7 and ICOSL to a helper T cell. Which
process is most directly impaired? | back 107 B. Helper T-cell maturation |
front 108 A high-affinity B cell outcompetes low-affinity B cells in a germinal
center. Which mechanism best explains this? | back 108 B. Better antigen plucking |
front 109 A patient’s draining lymph node is swollen after cellulitis. Which
combined mechanism best explains the swelling? | back 109 A. Lymphocyte loss, neutrophil apoptosis |
front 110 A virgin T cell enters intestinal lymphoid
tissue. Which receptor-ligand pair is most likely used? | back 110 C. α4β7–MadCAM-1 |
front 111 A virgin T cell enters a nonintestinal lymph
node through HEVs. Which pair is most
relevant? | back 111 D. L-selectin–GlyCAM-1 |
front 112 A mucosa-activated experienced T cell leaves the lymphoid
organ. Which change best predicts its future homing?
| back 112 A. More α4β7 expression |