Final exam biol 5500 New Study Guide
Questions with Actual Detailed
Answers.
primary vs secondary immunodeficiency diseases - Answer primary: inherited defects in
components of the immune system
secondary: caused by environmental factors such as suppressive drugs or infections
Types of primary immunodeficiency - Answer 1. dominant: patents inherit one defective and
one normal allele
2. recessive: only manifest in patients who inherit the defective allele from both parents
3. X-linked: caused by recessive defects in genes on the X chromosome
defects of IL-2 receptor gamma chain - Answer causes SCID
- pt has no T cells as a result of defected IL-2 gamma receptor
- numerous cytokine-mediated functions are lost if the common gamma chain among these dif
cytokine receptors are deficient
- no B cell maturation, NK development, hematopoeisis, T cell dev, class switching, and
peripheral T cell homeostasis
which chains of the IL-2 receptor can function as the receptor, though at a lower affinity than
with all 3? - Answer alpha
what are the cytokines that utilize the common gamma chain and the populations they
influence: - Answer - IL-21: B cell maturation
- IL-15: NK development
- IL-9: hematopoiesis
- IL-7: T cell dev
- IL-4: class switching
-IL-2: peripheral T cell homeostasis
IFN-gamma receptor deficiency - Answer - results in no macrophage activation
, - a small portion become long-lived memory cells
differences between humoral (antibody) and cellular immunity - Answer 1. B cell memory:
continuous production of antibody even after the resolution of the disease
- antibodies to pathogens are maintained for long periods of time
2. T cell memory: effector functions (cytokine production and cytolysis) are maintained for a few
weeks but these functions cease in the memory phase until antigen is encountered again
differences between memory B cells and plasma cells - Answer 1. memory B cells: found
predominantly in spleen and lymph nodes
- memory B cells do not actively secrete antibody, but respond to antigen by rapid division
giving rise to more memory B cells and by differentiating into plasma cells
2. plasma cells: reside primarily in BM; constantly secrete antibody, not stimulated by antigen bc
they have no surface BCR and they dont divide.
why do most vaccines require boosters? - Answer - because during the first response you
produce primarily IgM, which is low affinity, but during the second exposure via the booster, you
produce high affinity IgG antibodies
which cytokines are required for the survival of long-lived T cells? - Answer - IL-7 and IL-15
- without these signals, the cell will undergo apoptosis
- memory T cells need contact with self-peptide: self-MHC complexes to continue to proliferate
memory T cells - Answer - following infection there are expansions of both CD8 and CD4 T
cells
- the size of the memory population is proportional to the peak size of the population during
expansion (5-10% of the peak size)
- the number of antigen specific CD8 T cells increases almost 10,000 fold compared to
preinfection
- even after contraction, the number of virus-specific cells is several orders of magnitude greater
than that of a naive human.
if the number of RSV-specific T cells at the peak of the T cell response against RSV infection was
10^6, what number of memory T cells would you expect to observe after contraction? - Answer
10^6 x.10 =10^5
Questions with Actual Detailed
Answers.
primary vs secondary immunodeficiency diseases - Answer primary: inherited defects in
components of the immune system
secondary: caused by environmental factors such as suppressive drugs or infections
Types of primary immunodeficiency - Answer 1. dominant: patents inherit one defective and
one normal allele
2. recessive: only manifest in patients who inherit the defective allele from both parents
3. X-linked: caused by recessive defects in genes on the X chromosome
defects of IL-2 receptor gamma chain - Answer causes SCID
- pt has no T cells as a result of defected IL-2 gamma receptor
- numerous cytokine-mediated functions are lost if the common gamma chain among these dif
cytokine receptors are deficient
- no B cell maturation, NK development, hematopoeisis, T cell dev, class switching, and
peripheral T cell homeostasis
which chains of the IL-2 receptor can function as the receptor, though at a lower affinity than
with all 3? - Answer alpha
what are the cytokines that utilize the common gamma chain and the populations they
influence: - Answer - IL-21: B cell maturation
- IL-15: NK development
- IL-9: hematopoiesis
- IL-7: T cell dev
- IL-4: class switching
-IL-2: peripheral T cell homeostasis
IFN-gamma receptor deficiency - Answer - results in no macrophage activation
, - a small portion become long-lived memory cells
differences between humoral (antibody) and cellular immunity - Answer 1. B cell memory:
continuous production of antibody even after the resolution of the disease
- antibodies to pathogens are maintained for long periods of time
2. T cell memory: effector functions (cytokine production and cytolysis) are maintained for a few
weeks but these functions cease in the memory phase until antigen is encountered again
differences between memory B cells and plasma cells - Answer 1. memory B cells: found
predominantly in spleen and lymph nodes
- memory B cells do not actively secrete antibody, but respond to antigen by rapid division
giving rise to more memory B cells and by differentiating into plasma cells
2. plasma cells: reside primarily in BM; constantly secrete antibody, not stimulated by antigen bc
they have no surface BCR and they dont divide.
why do most vaccines require boosters? - Answer - because during the first response you
produce primarily IgM, which is low affinity, but during the second exposure via the booster, you
produce high affinity IgG antibodies
which cytokines are required for the survival of long-lived T cells? - Answer - IL-7 and IL-15
- without these signals, the cell will undergo apoptosis
- memory T cells need contact with self-peptide: self-MHC complexes to continue to proliferate
memory T cells - Answer - following infection there are expansions of both CD8 and CD4 T
cells
- the size of the memory population is proportional to the peak size of the population during
expansion (5-10% of the peak size)
- the number of antigen specific CD8 T cells increases almost 10,000 fold compared to
preinfection
- even after contraction, the number of virus-specific cells is several orders of magnitude greater
than that of a naive human.
if the number of RSV-specific T cells at the peak of the T cell response against RSV infection was
10^6, what number of memory T cells would you expect to observe after contraction? - Answer
10^6 x.10 =10^5
