Which of the following Toll-like receptors are expressed exclusively in NK cells? (Select
all that apply.)
a.TLR3
b.TLR4
c.TLR7
d.TLR8
e.TLR9.
Individuals who fail to express functional Bruton’s tyrosine kinase exhibit all of the
following characteristics except
a.B-cell development is blocked at the immature B-cell stage.
b.They are usually male because the Btk gene is on the X chromosome.
c.They suffer from an immune deficiency known as X-linked agammaglobulinemia
(XLA).
d.Recurrent infections with extracellular bacteria are common.
e.They benefit from treatment with immunoglobulin infusions.
Severe combined immune deficiency (SCID) describes a condition in which neither _____
nor _____ are functional.
a.classical; alternative pathways of complement
b.T-cell-dependent antibody responses; cell-mediated immune responses
c.innate; acquired immune responses
d.MHC class I; MHC class II molecules.
Which of the following is matched incorrectly?
a. light-chain locus: chromosome 2
b.coding joint: nonhomologous end-joining of V and J gene segments
c. light-chain locus: four or five C gene segments
d.affinity maturation: addition of P and N nucleotides
e.recombination signal sequence: heptamer-spacer-nonamer.
A.Explain the challenges associated with generating effective vaccines against
encapsulated bacteria.
B.How have these challenges been overcome?
C.Explain the cellular events required for the production of protective IgG antibodies
against bacterial polysaccharide components and the development of memory.
After a campus outbreak of Neisseria meningitidis (meningococcal serogroup B), a
devastating bacterial disease, which affected at least eight students at Princeton University,
the US Food and Drug Administration approved the use of Bexsero to prevent the
development of additional cases on that campus. Bexsero is considered to provide broader
protective coverage than the US-licenced vaccines conventionally used against this
disease. Which of the following methodologies was used to develop Bexsero?
a.conjugation of neisserial capsular polysaccharide to tetanus toxoid
b.reverse vaccinology
c.formalin treatment of secreted toxins
d.production of a combination vaccine that includes DTP plus a meningococcal
polysaccharide diphtheria toxoid conjugate
e.engineering a nonpathogenic cattle strain of N. meningitidis to express antigens
associated with pathogenic human strains.
Commensal microorganisms in the gastrointestinal tract facilitate all of the following
except _____.
a.compete with pathogenic variants for nutrients and space
b.convert toxic substances to benign derivatives
c.degrade plant fibers to make their nutrients available
d.secrete enzymes required for protein degradation
e.synthesize essential metabolites
f.induce the development of gut-associated lymphoid tissue.
_____ is a soluble protein. (Select all that apply.)
a.TLR4
b.CD14
c.lipopolysaccharide-binding protein (LBP)
d.CXCR1
e.mannose-binding lectin.
Which of the following is an acute-phase protein that enhances complement fixation?
a.TNF-\alpha
b.mannose-binding lectin
c.fibrinogen
d.LFA-1
e.CXCL8.
Which of the following would occur after the production of a functional chain as a
pre-B-cell receptor?
a.RAG proteins are degraded.
b.The chromatin structure of the heavy-chain locus is reorganized to prevent gene
rearrangement.
c.Transcription of the RAG1 and RAG2 genes ceases.
d.There is allelic exclusion of a second chain.
e.All of the above would occur.
A.Name the parts of the body where epithelia act as barriers to infection.
B.Describe the three main ways in which epithelia carry out this barrier function, giving
details of the mechanisms employed.