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The circulatory route through a lymphoid tissue for both immature B cells and mature B
cells that do not encounter specific antigen is:
a.bloodstream HEV of lymphoid cortex primary lymphoid follicle efferent
lymphatic vessel
b.afferent lymphatic vessel primary lymphoid follicle HEV of lymphoid cortex
efferent lymphatic vessel
c.afferent lymphatic vessel medullary cords primary lymphoid follicle
efferent lymphatic vessel
d.primary lymphoid follicle HEV of lymphoid cortex afferent lymphatic vessel
efferent lymphatic vessel
e.bloodstream afferent lymphatic vessel HEV of lymphoid cortex efferent
lymphatic vessel.
Which of the following activities are most closely associated with natural killer cells?
a.production of TNF-\alpha
b.lysis of virus-infected cells
c.phagocytosis of bacteria
d.release of reactive oxygen intermediates
e.production of IFN-\gamma.
A plasma cell is characterized by which of the following features? (Select all that apply.)
a.It differentiates in the medulla of lymph nodes and the bone marrow.
b.It dedicates 10-20% of total protein synthesis to antibody production.
c. Levels of MHC class II molecules are elevated.
d.It undergoes extensive proliferation in germinal centers.
e.It produces secreted immunoglobulin instead of the membrane-bound form.
Which of the following statements regarding herpes simplex virus is false?
a.Because sensory neurons express low levels of MHC class I molecules, they provide
appropriate sites for viral dormancy.
b.Reactivation of herpesviruses follows stressful incidents.
c.Cold sores develop as a consequence of CD8 T-cell killing.
d.In one's lifetime, periodic episodes of reactivation are common.
e.Herpes simplex virus infects B lymphocytes.
_____ in the switch regions positioned 5' to each heavy-chain C gene is induced by _____.
a.Somatic hypermutation; TI antigens
b.Chromatin remodeling; B-cell co-receptor signaling
c.Recombination; survival signals received from follicular dendritic cells
d.Transcription; helper T-cell cytokines
e.Gene repression; apoptotic signals received from tingible body macrophages.
The enzyme that generates diacylglycerol (DAG) and inositol trisphosphate (IP3) from
phosphatidylinositol bisphosphate (PIP2) is _____.
a.protein kinase C- (PKC- )
b.calcineurin
c.phospholipase C- (PLC- )
d.protein tyrosine kinase ZAP-70
e.protein tyrosine kinase Lck
T-cell receptors interact not only with peptide anchored in the peptide-binding groove of
MHC molecules, but also with
a.anchor residues
b.peptide-binding motif
c.variable amino acid residues on helices of the MHC molecule
d. -microglobulin
e.invariant chain.
A primary immune response against influenza virus produces antibodies that bind to
_____.
a.hemagglutinin and neuraminidase
b.variable surface glycoproteins
c.EBNA-1
d.protein toxins
e.gp41 and gp120.
An important advantage of having two gene loci ( and ) for the light chain is
a.that the likelihood of a successful rearrangement of light-chain genes increases.
b.that immunoglobulins are homogeneous and not heterogeneous in mature B cells.
c.that different effector functions are conferred by the two different light-chain loci.
d.that surrogate light-chain transcription cannot compete with and transcription and
enables B-cell development.
e.all of the above.
During a primary immune response IgM sometimes switches to IgE. Which of the
following best describes the consequence of this early switch?
a.The B cell would switch again to IgG3.
b.The B cell would remain in the germinal center but would not differentiate into a plasma
cell.
c.The B cell would die by apoptosis.
d.The IgE produced would have low affinity for antigen.
Explain how secondary lymphoid tissues of the mucosa are (A) similar to and (B) different
from secondary lymphoid tissues elsewhere in the body (the systemic immune system).
Superantigens bind to all of the following molecules except _____.
a.CD4
b.MHC class II chain
c.CD28
d.T-cell receptor chain.
Which of the following cytokines is secreted by both CD8 T cells and TH1 cells? (Select
all that apply.)
a.IL-4
b.IL-5
c.IFN-
d.TNF-
e.IL-13
f.lymphotoxin (LT).
Which of the following statements regarding Omenn syndrome is incorrect?
a.A bright red, scaly rash is due to a chronic inflammatory condition.
b.Affected individuals are susceptible to infections with opportunistic pathogens.
c.It is invariably fatal unless the immune system is rendered competent through a bone
marrow transplant.
d.It is the consequence of complete loss of RAG function.
e.There is a deficiency of functional B and T cells.
f.It is associated with missense mutations of RAG genes.
