Download Document

Biol 430
Question Bank
Immunotherapy
1. A child who had not yet received a tetanus immunization received a deep wound to his heel by
stepping on the lid of an old metal can. His mother rushed him to the health clinic where the
child’s wound was cleaned and sutured (it required 5 stitches). Adding “insult to the injury”, the
child was also required to get a shot of the tetanus antitoxin.
A. Why was the child given the tetanus antitoxin instead of the tetanus toxoid?
B. Having received the antitoxin, will the child be protected against a similar injury in the
future?
2. Suppose that you were developing a new vaccine from polysaccharide components of a bacterial
capsule. Initially, you start with the purified form of a single type of polysaccharide. Explain why
each of the following vaccine modification may improve the immune response?
A. covalently coupling the polysaccharide to a protein carrier.
B. adding aluminum hydroxide.
C. using more than one type of polysaccharide in combination.
D. using the vaccine for older children and adults, but not infants
E. using a recombinant virus expressing the polysaccharide.
A colleague suggests that since the bacteria you are working with is an intracellular pathogen that
you should instead be developing live, attenuated form of the vaccine.
F. What reasons could you give him for preferring the molecular component approach?
G. For what reasons may your colleague be right?
3. The oral Sabin (live attenuated) polio vaccine is no longer recommended in the US, but is used
in other countries where the incidence of polio is still a serious problem. Why.
Biol 430
Question Bank
Immunotherapy
Page 1
4. All other differences between the vaccines being equal:
A. for a disease with a short incubation period would a live attenuated vaccine or a dead
inactivated vaccine be preferred?
B. What about for a disease with a long incubation period?
C. What type of vaccine (other than the two mentioned above) would be called for if the
pathogen will release a serious toxin shortly after the infection occurs
D. Explain you answers.
5. Some parents worry that combinational vaccines such as MMR or DTaP might “overwhelm” the
immune system and leave a child more susceptible to other diseases. Based upon your knowledge
of the mechanisms of the immune system, explain why this fear is unfounded.
6. For each of the following treatments, indicate if it is an example of passive (‘P’) immunization,
active (‘A’) immunization, therapeutic (‘T’)immunization, or neither (‘N’):
___ tetanus antitoxin
___ tumor antigens
___ maternal IgA
___ tetanus (DTaP) vaccine
___ polio vaccine
___ IVIG
___ antiviral drugs
Biol 430
Question Bank
Immunotherapy
Page 2
7. For each one of the following characteristics, indicate which type of vaccine that characteristic
best describes:
____ potential risk of causing infection
____ most likely to activate cell mediated arm
A. Inactivated pathogen
____ carries many epitopes, activates a
B. Toxoid
humoral response better than cell-mediated
C. Molecular component
____ most likely to require refrigeration.
D. Attenuated pathogen
____ carries few epitopes, but is very safe
____ active against a toxic product of a pathogen
8. Identify these vaccines:
Protects against
Vaccine
which disease(s)
Type of vaccine
MMR
________________________
_____________________
DTaP
________________________
_____________________
HiB
________________________
_____________________
PCV
________________________
_____________________
HBsAG
________________________
_____________________
FluMist
________________________
_____________________
OVP
________________________
_____________________
9. While blood type incompatibility is rarely a problem during pregnancy, Rh incompatibility can
be.
A. Rh incompatibility will occur only if the mother is Rh- and the child is Rh+? Why?
B. Why do problems posed by Rh incompatibility manifest itself on subsequent but not the
first pregnancy involving an Rh+ child?
C. Rhogam, the treatment for Rh incompatibility disease, needs to be administered shortly
after delivery in order to be effective. Why?
D. Is Rhogam given to the mother or the child? ________________________
E. Considering the mechanism of action, need rhogam be administered after each pregnancy
involving an Rh+ child, or only the first?
Biol 430
Question Bank
Immunotherapy
Page 3
10. The origin of new strains of influenza involves both genetic drift and genetic shift.
A. Which one of these mechanism yields the largest genetic variations?
B. Which mechanism is principally responsible for annual variations.
C. Explain how genetic shift might yield a H2N1 influenza strain from H3N1 and H2N2?
D. Explain why a new pandemic form of influenza, will likely arise from antigenic shift
followed by drift.
E. Many people fear that the world’s health services would be unable to stem a pandemic if a
deadly form of influenza reemerges. Describe the challenges to developing and
distributing a vaccine for a new pandemic form of influenza.
11. There are several compounding factors hindering the development of vaccines for protozoal
diseases, such as malaria. Explain each of these factors why it poses a challenge to vaccine
development:
A. geographic distribution in poor nations
B. complex life cycles of the pathogens
C. transmission through a vector (e.g., mosquito)
D. abiltity of the pathogens to undergo antigenic shift
E. slow onset and chronic nature of disease symptoms
Can you suggest a why transmission through a vector may pose a unique opportunity for an
alternative strategy to control spread of a disease?
Biol 430
Question Bank
Immunotherapy
Page 4
12. Various B-cell surface antigens have been targets for B-cell targeted immunotherapy.
A. What are two types of immunotherapies strategies that could target B-cell surface
antigens?
B. What are the potential unintended consequences of immunotherapies that target lymphoid
cells for destruction?
The diagram below shows when some B-cell surface markers are expressed during B-cell
development.
Rituximab targets CD20 and Blinatumomab targets CD19. What would be the disadvantages of
immunotherapies for a B-cell cancers that targeted:
C. CD34?
D. CD21?
E. What would be several ideal characteristics of a B-cell surface marker that would make it
ideal as a target for B-cell cancer immunotherapy
13. The macromolecules of cancer cells should be recognized as self-antigens and thus be ignored
by the immune system. Nevertheless, many types of cancer can be recognized and attached by
Immune cells. What are several potential origins of “cancer cell antigens” that the immune system
might recognize?
Biol 430
Question Bank
Immunotherapy
Page 5
14. Evidence suggests both serum IgG and mucosal IgA are important to protection against lethal
influenza H5N1, although the relative importance of these immunoglobins and how they are best
generated is yet unresolved. Valdy et al compared the efficacy of different combinations of
intramuscular (IM) and intranasal (IN) immunizations using a mouse system.
Two groups of 3 female BALB/c mice each were immunized twice at a 3-week interval
with HA from the Jiangsu strain, by IM/IM, IN/IN, IN/IM, or IM/IN routes of immunizations. At 7
days after the final immunization, pools of 3 mice each were sacrificed and single-cell suspensions
were prepared from cervical lymph nodes and analyzed by ELISPOT assay.
The ELISpot assay is used to count the number of cells that secrete a
particular type of antigen by distributing the cell suspension over
membranes coated with antibodies against the antigen of interest. In this
case the membranes were coated with either anti-IgG or anti-IgA antibodies,
which would bind to IgG or IgA secreted from the plasma cells. After an
incubation period, the cells were washed off, and the membrane is treated
with a secondary antibody / substrate staining system. The position of each
antigen secreting cell appears as a spot, as shown in the image to the right.
An animation of the Elispot procedure is also available from the Biol 430
download web page.
In the graph below, the results are presented as the number of antibody-secreting cells
(ASC) per million mononuclear cells (MNC).
A. Explain how the spots in the sample
ELISpot image are created.
B. Which treatment yielded the highest number of IgA secreting cells in the cervical lymph
nodes?
C. Which treatment yielded the fewest IgG and IgA secreting cells?
D. When IN and IM immunization are used in combination, does the order of the
immunizations matter?
E. Do these results support your expectations for the nature of a humoral response to different
routes of exposure? Explain.
Vajdy M, Baudner B, Del Giudice G, O’Hagan D. 2007. A vaccination strategy to enhance mucosal and systemic
antibody and T cell responses against influenza. Clinical Immunology123: 166–175.
Biol 430
Question Bank
Immunotherapy
Page 6