The significance of MAdCAM-1 on the endothelium of blood vessels is that it binds to
_____.
a.the integrin on effector lymphocytes homing to mucosal tissues
b.B cells destined to become intraepithelial lymphocytes
c.dendritic cells, and causes the upregulation of antigen processing and presentation
d.the chemokine CCL25, which is secreted by gut epithelia
e.intestinal helminths, and mediates killing of these parasites.
The human thymus begins to degenerate as early as one year after birth. This process is
called ______ and is marked by the accumulation of ___ once occupied by thymocytes.
a.thymectomy; dendritic cells
b.involution; fat
c.differentiation; T cells
d.negative selection; T cells
e.involution; thymic stroma.
If a centrocyte does not interact with antigen and engage CD40 shortly after its derivation,
then _____.
a.it recommences somatic hypermutation
b.it undergoes apoptosis
c.it moves back into the dark zone of the germinal center and switches its isotype
d.its surface immunogloblulin levels decrease and proliferation recommences.
A.What does the term seroconversion mean in relation to an HIV infection?
B.What relationship does seroconversion have to the time course of an HIV infection?
NK cells express all of the following proteins either on endosome membranes or on their
cell surface with the exception of _____. (Select all that apply)
a.CD3
b.type I interferon receptor
c.CR3
d.CD56
e.LFA-1
f.activating receptors
g.inhibitory receptors
h.TLR3
i.TLR4
j.IL-12R\beta1 and IL-12R\beta2.
A.What is the risk to a population that reduces its use of particular vaccines over a period?
B.Identify two cases in which this has happened and the underlying reason for distrust in
the benefit of the vaccine.
Memory B cells differ from memory T cells in the following ways. (Select all that apply.)
a.They suppress naive antigen-specific lymphocytes during secondary immune responses.
b.They recirculate only through secondary lymphoid organs.
c.They secrete their antigen receptors throughout their life-span.
d.They generate long-lived clones of memory cells during the primary immune response.
All of the following are true regarding thyroglobulin except _____.
a.its tyrosine residues are iodinated and cross-linked
b.it is broken down to produce thyroid hormones
c.it is stored in follicles of the thyroid
d.it signals the pituitary gland to stop releasing thyroid-stimulating hormone
e.it is synthesized initially as a glycoprotein by thyroid epithelial cells.
A.What are tumor-associated antigens?
B.How do they originate?
C.Give two examples together with the type of tumor they come from.
Identify the mismatched association.
a.Syk: Ig cytoplasmic tails
b.tyrosine kinase Lyn: CD81
c.B-cell co-receptor: CD21/CD19/CD81
d.C3b fragments: C3d and iC3b
e.C3b/CR1: factor I
f.hyper-IgM syndrome: CD40 ligand deficiency.
Autoimmune diseases, which are classified on the basis of the effector mechanism that
causes the symptoms, include all of the following types of hypersensitivity reaction except
_____.
a.type I
b.type II
c.type III
d.type IV.
Lymphoblasts upregulate a transcription factor called _____ when they terminally
differentiate into plasma cells.
a.NF B
b.Bcl-xL
c.B-lymphocyte induced maturation protein 1 (BLIMP-1)
d.CD40
e.ICAM-1.
Which of the following is classified as a pro-drug? (Select all that apply.)
a.azathioprine
b.cyclophosphamide
c.cyclosporin
d.prednisone
e.rapamycin
f.mycophenolate mofetil.
The immunoglobulin heavy-chain gene consists of _______ segments, whereas the
immunoglobulin light-chain gene consists of _______ segments.
a. ;
b.VDJ; VJ
c.VJ; VDJ
d.P; N
e.RAG-1; RAG-2.
The pol gene of HIV produces all of the following except _____.
a.integrase
b.protease
c.matrix protein
d.reverse transcriptase.
What evidence supports the proposal that MHC diversity evolved by natural selection
caused by infectious pathogens rather than exclusively by random DNA mutations?
T-cell receptors do not undergo isotype switching. Suggest a possible reason for this.
What are the main differences between innate immunity and adaptive immunity?
Identify three reasons why memory B cells respond more forcefully and effectively during
secondary immune responses than naive B cells during primary immune responses.
Which of the following is the first stage of T-cell receptor gene rearrangement in T
cells?
Explain why splenectomy is sometimes carried out in patients with persistent type II
autoimmune diseases that affect leukocytes.