What are the roles of the following molecules in the signal transduction pathway leading
from the T-cell receptor: (i) the CD3 complex; (ii) protein tyrosine kinase Lck; (iii) CD45;
(iv) ZAP-70; (v) the chain; (vi) inositol trisphosphate (IP3); (vii) calcineurin?
Which of these characteristics is not true of ?
a.When it acts on target cells, it enhances the engulfment and killing of bacteria.
b.It is the major activating cytokine of macrophages.
c.It activates the JAK-STAT signal transduction pathway after binding to its cognate
receptor.
d.It is secreted by CD8 cytotoxic T cells, CD4 cells, and NK cells.
e.It is secreted and functions as a monomer but facilitates the dimerization of its receptor.
f.It is able to render target cells responsive even if they express only one functional allele
of .
Chronic granulomatous disease (CGD), a condition resulting in chronic bacterial and
fungal infections, is caused by one or more defects in _____, compromising the ability of
macrophages to _____.
a.CD18; produce cell adhesion molecules
b.NADPH oxidase; produce superoxide radical ( )
c.CD40 ligand; produce GM-CSF
d.C5-C9; defend against Neisseria
e.C3; opsonize capsulated bacteria.
If viewing the three-dimensional structure of a T-cell receptor from the side, with the T-cell
membrane at the bottom and the receptor pointing upwards, which of the following is
inconsistent with experimental data?
a.The highly variable CDR loops are located across the top surface.
b.The membrane-proximal domains consist of C and C .
c.The portion that makes physical contact with the ligand comprises V and C , the
domains farthest from the T-cell membrane.
d.The transmembrane regions span the plasma membrane of the T cell.
e.The cytoplasmic tails of the T-cell receptor and chains are very short.
Giulia McGettigan was born full term with a malformed jaw, cleft palate, a ventricular
septal defect, and hypocalcemia. Within 48 hours of birth she developed muscle tetany,
convulsions, tachypnea, and a systolic murmur. A chest X-ray showed an enlarged heart
and the absence of a thymic shadow. Blood tests showed severely depleted levels of CD4
and CD8 T cells; B-cell numbers were low but within normal range. Parathyroid hormone
was undetectable. Fluorescence in situ hybridization of the buccal mucosa revealed a small
deletion in the long arm of chromosome 22 . Giulia failed to thrive and battled chronic
diarrhea and opportunistic infections, including oral candidiasis and Pneumocystis
jirovecii, the latter infection causing her death. Giulia most probably had which of the
following immunodeficiency diseases?
a.AIDS
b.DiGeorge syndrome
c.bare lymphocyte syndrome
d.chronic granulomatous disease
e.hyper IgM syndrome.
_____ binds to and retains NF\kappaB in the cytosol.
a.MyD88
b.TRAF6
c.I\kappaB
d.I\kappa\kappa
e.IRAK4.
Hematopoietic stem cell transplantation is appropriate for all of the following conditions
except _____.
a.thalassemia major
b.Wiskott-Aldrich syndrome
c.Fanconi’s anemia
d.cirrhosis of the liver
e.sickle-cell anemia
f.non-Hodgkin’s lymphoma.
Which of the following statements is false regarding CD8 T cells?
a.CD8 T cells have only one effector function, which is cytotoxicity.
b.Compared with naive CD4 T cells, naive CD8 T cells have more stringent requirements
for co-stimulatory activity.
c.Effector CD8 cells require co-stimulation to kill their target cells.
d.The most potent antigen-presenting cell for naive CD8 T cells is the dendritic cell.
Adaptive immune responses targeted at infections by helminth worms and other parasitic
multicellular animals employ all of the following except _____. (Select all that apply.)
a.CD8 T cells
b.IgE
c.eosinophils
d.mast cells
e.CD4 cells
f.basophils
g.neutrophils
h. .
Differentiate between the following types of vaccine and give an example of each: (A)
inactivated virus vaccines; (B) live-attenuated virus vaccines; (C) subunit vaccines; (D)
toxoid vaccines; (E) conjugate vaccines; and (F) combination vaccines.
Indicate whether each of the following statements is true (T) or false (F).
Match the treatment in column A with its target in column B.
Explain briefly how penicillin initiates a type I hypersensitivity response.
Match the term in Column A with its description in Column B.
During T-cell receptor _____-gene rearrangement, two D segments may be used in the
final rearranged gene sequence, thereby increasing overall variability of this chain.
Match the condition/disease in column A with its description in column B. Use each
answer only once.
In T cells, allelic exclusion of the -chain locus is relatively ineffective, resulting in the
production of some T cells with two T-cell receptors of differing antigen specificity on
their cell surface.
A-Will both these receptors have to pass positive selection for the cell to survive? Explain
your answer.
B-Will both receptors have to pass negative selection for the cell to survive? Explain your
answer.
C-Is there a potential problem in having T cells with dual specificity surviving these
selection processes and being exported to the periphery?
You are going to use flow cytometry to determine the proportion of developing B cells in
the bone marrow that are immature, anergic, or mature. You have three monoclonal
antibodies specific for three different B-cell surface proteins. The first has specificity for
the cell-surface protein CD19, which is expressed by all developing and mature B cells;
the second is specific for the Fc region of IgD; and the third is specific for the Fc region of
IgM. The antibodies are conjugated to three different fluorescent tags that can be detected
and distinguished by the flow cytometer.
A-Use histograms to show your analysis of CD19-positive cells and indicate which part of
your histogram you would gate to analyze IgM and IgD expression. Indicate the gated
population with an arrow.
B-Using a two-dimensional dot plot, compare the expression of IgD and IgM of these
gated cells, and say which of these populations represents (i) immature B cells, (ii) mature
B cells, and (iii) anergic B cells.