IMMUNOLOGY - EXAM 1 - CASE STUDY
QUESTIONS - TTU - DR.BECK - EXAM
QUESTIONS AND ANSWERS (VERIFIED
AND UPDATED)
What is the effect of being born without a spleen (congenital asplenia)? - ANS A child being
born without a spleen is more susceptible to middle ear infections, pneumonia, and blood
stream infections that can be life threatening. A young child that has their spleen removed is
also susceptible to those things until later in life. The spleen is important for clearing capsulated
bacterial infection.
Wha tis the effect of losing your spleen later in life? Why the difference? - ANS Later on in
life, losing the spleen does not have too much of an impact. This is because younger children do
not have as strong as an immune system as healthy adults do; this is why children without a
spleen are more likely to develop capsulated bacterial infections than adults without a spleen.
The adult has built up immune responses over their lifetime.
The children responded to the typhoid vaccine which is injected in the arm but only some of the
children responded to the sheep blood. Why the difference? What does it tell you about the
development of antibodies? - ANS The sheep blood is injected into the blood stream
(systemic) which is closely related and works with the spleen. The typhoid vaccine is goes
through the mucosal compartment of the immune system. This is why all the children
responded normally to the typhoid vaccine. The children without a spleen did not respond to
the sheep blood because their systemic immune response is comprised, but their mucosal
immune response is perfectly fine.
@2026/2027 ALLRIGHTS RESERVED.
, What is the most important cytokine for macrophage activation? - ANS INF-gamma
What is the effect of loss of the ability to detect that cytokine on the immune response? -
ANS Cytokines activate macrophages, which is what's needed to effectively kill
mycobacterium. If cytokines go undetected, the macrophages are not being activated, therefore
the immune response is not present.
INF-gamma receptor deficiency: how does this lead to increased susceptibility to Mycobacteria?
- ANS INF-gamma receptor deficiency leads to decreased binding of INF-gamma to
macrophages. This leads to macrophages not being activated by means of a phosphorylation
cascade. The resting macrophage will have an 80% survival of the mycobacterium, this means
the infection will continue to grow.
What is the immunodeficiency associated with Hereditary Angioedema? - ANS C1-INH
deficiency
What is the effect of C1 INH on kallikrein? - ANS C1-INH is used to inhibit killakrein, a plasma
protease responsible for cleaving Bradykinin and kallidin off of their receptors.
How do bradykinin and C2 kinin explain part of the symptoms seen with hereditary
angioderma? - ANS If we have a deficiency in C1-INH, then killakrein is not turned off, which
means that it can cleave bradykinin. Bradykinin influences vasodilation and inflammation.
What are the symptoms of angioedema? - ANS - swelling/inflammation, pain, decreased C2
and C4 in the blood
What disease does deficiency in C8 make you much more susceptible to? - ANS Neisserria
infections
@2026/2027 ALLRIGHTS RESERVED.
QUESTIONS - TTU - DR.BECK - EXAM
QUESTIONS AND ANSWERS (VERIFIED
AND UPDATED)
What is the effect of being born without a spleen (congenital asplenia)? - ANS A child being
born without a spleen is more susceptible to middle ear infections, pneumonia, and blood
stream infections that can be life threatening. A young child that has their spleen removed is
also susceptible to those things until later in life. The spleen is important for clearing capsulated
bacterial infection.
Wha tis the effect of losing your spleen later in life? Why the difference? - ANS Later on in
life, losing the spleen does not have too much of an impact. This is because younger children do
not have as strong as an immune system as healthy adults do; this is why children without a
spleen are more likely to develop capsulated bacterial infections than adults without a spleen.
The adult has built up immune responses over their lifetime.
The children responded to the typhoid vaccine which is injected in the arm but only some of the
children responded to the sheep blood. Why the difference? What does it tell you about the
development of antibodies? - ANS The sheep blood is injected into the blood stream
(systemic) which is closely related and works with the spleen. The typhoid vaccine is goes
through the mucosal compartment of the immune system. This is why all the children
responded normally to the typhoid vaccine. The children without a spleen did not respond to
the sheep blood because their systemic immune response is comprised, but their mucosal
immune response is perfectly fine.
@2026/2027 ALLRIGHTS RESERVED.
, What is the most important cytokine for macrophage activation? - ANS INF-gamma
What is the effect of loss of the ability to detect that cytokine on the immune response? -
ANS Cytokines activate macrophages, which is what's needed to effectively kill
mycobacterium. If cytokines go undetected, the macrophages are not being activated, therefore
the immune response is not present.
INF-gamma receptor deficiency: how does this lead to increased susceptibility to Mycobacteria?
- ANS INF-gamma receptor deficiency leads to decreased binding of INF-gamma to
macrophages. This leads to macrophages not being activated by means of a phosphorylation
cascade. The resting macrophage will have an 80% survival of the mycobacterium, this means
the infection will continue to grow.
What is the immunodeficiency associated with Hereditary Angioedema? - ANS C1-INH
deficiency
What is the effect of C1 INH on kallikrein? - ANS C1-INH is used to inhibit killakrein, a plasma
protease responsible for cleaving Bradykinin and kallidin off of their receptors.
How do bradykinin and C2 kinin explain part of the symptoms seen with hereditary
angioderma? - ANS If we have a deficiency in C1-INH, then killakrein is not turned off, which
means that it can cleave bradykinin. Bradykinin influences vasodilation and inflammation.
What are the symptoms of angioedema? - ANS - swelling/inflammation, pain, decreased C2
and C4 in the blood
What disease does deficiency in C8 make you much more susceptible to? - ANS Neisserria
infections
@2026/2027 ALLRIGHTS RESERVED.
