PCB4233 Exam 3 Quiz Questions With
Correct Solutions, Already Passed!!
It is well documented that antibody affinities for an immunizing antigen continue to
increase upon successive rounds of immunization (i.e. secondary, tertiary, etc). This is
due to the fact that: - CORRECT ANSWER-memory B cells can re-enter germinal
centers and undergo additional somatic hypermutation
What is the cell type most characteristically associated with the gut associated lymphoid
tissue (GALT)? - CORRECT ANSWER-microfold (M) cells
Intestinal epithelium and lamina propria contain a large number of effector T cells,
plasma cells, and cytokine secreting leukocytes even in the absence of infection;
however, such an inflammatory state does not cause tissue damage because their
effects are balanced by the presence of Treg cells and production of anti-inflammatory
cytokines such as IL-10 - CORRECT ANSWER-true
Gut homing activated T cells express the following chemokine receptor and adhesion
molecule combination - CORRECT ANSWER-CCR9; alpha4/beta7 integrin
Defects in which of the following proteins do NOT result in severe combined
immunodeficiency (SCID)? - CORRECT ANSWER-AID
Bruton's X-linked agammaglobulinemia (XLA) results from a mutation in: - CORRECT
ANSWER-Bruton's tyrosine kinase (Btk)
Patients with Wiskott-Aldrich syndrome show severely impaired responses to vaccines
such as the tetanus vaccine, which is composed of the inactivated tetanus toxin. Yet,
these patients can generate normal antibody responses to bacterial polysaccharide
antigens. This selective defect in antibody response in Wiskott-Aldrich syndrome
patients is due to: - CORRECT ANSWER-defective polarized secretion of cytokines by
CD4 T cells
Defects in LFA-1 gene lead to: - CORRECT ANSWER-Leukocyte adhesion deficiency
(LAD)
Which method is most characteristically used by trypanosomes to escape the immune
response? - CORRECT ANSWER-switching of VSGs (variable surface glycoproteins)
, Influenza virus has a segmented RNA genome. Point mutations in the influenza virus
genome is called ________(1), which causes milder and limited disease. In contrast,
antigenic changes by reassortment of the segmented RNA genome are known as
__________(2), which causes more severe disease and higher mortality - CORRECT
ANSWER-(1) antigenic drift
(2) antigenic shift
Malaria is caused by Plasmodium falciparum and Plasmodium vivax. These pathogens
are transmitted when an individual is bitten by a Plasmodium-infected mosquito. This
route of transmission: - CORRECT ANSWER-allows the parasite to avoid the normal
mechanisms blocking infections at barrier surfaces
Herpesviruses are a class of viruses that establish life-long infections in human hosts.
One herpesvirus, Herpes Simplex virus, causes recurrent cold sores in infected
individuals. Thus, in spite of a robust antiviral CD8 T cell response, these individuals still
suffer from periodic virus-induced cold sores following exposure to UV light or certain
hormones or other stressors. This antiviral CD8 T cell response: - CORRECT
ANSWER-eliminates infected epithelial cells but not infected neurons
In the type III immune response, both TH17 and ILC3 cells secrete IL17 to activate: -
CORRECT ANSWER-neutrophils
A few days after a virus infection is cleared, the majority of virus specific CD8 T cells
start to die. Death of these T cells is caused by: - CORRECT ANSWER-Fas induced
apoptosis (extrinsic pathway)
Which of the following cytokines is important to maintain T cell memory - CORRECT
ANSWER-IL-7
Effector memory T cells (Tem) can be distinguished from the central memory T cells
(Tcm) by: - CORRECT ANSWER-expression level of CCR7
The immune response is a dynamic process that initiates with an antigen independent
response, which becomes more focused and powerful as it develops antigen specificity.
Once the adaptive immune system develops, a single type of cell or immunoglobulin is
capable of eliminating any type of pathogen. - CORRECT ANSWER-False
In response to an intracellular bacterial or viral infection, effector TH1 cells,
macrophages, NK cells and CD8 cytotoxic effector cells are all recruited to the site of
infection. The coordinated recruitment of all of these cell types is orchestrated by: -
CORRECT ANSWER-the shared expression of chemokine receptors on these different
cell types
Which of the surface proteins is neither a receptor nor a co-receptor for HIV? -
CORRECT ANSWER-CD8
Correct Solutions, Already Passed!!
It is well documented that antibody affinities for an immunizing antigen continue to
increase upon successive rounds of immunization (i.e. secondary, tertiary, etc). This is
due to the fact that: - CORRECT ANSWER-memory B cells can re-enter germinal
centers and undergo additional somatic hypermutation
What is the cell type most characteristically associated with the gut associated lymphoid
tissue (GALT)? - CORRECT ANSWER-microfold (M) cells
Intestinal epithelium and lamina propria contain a large number of effector T cells,
plasma cells, and cytokine secreting leukocytes even in the absence of infection;
however, such an inflammatory state does not cause tissue damage because their
effects are balanced by the presence of Treg cells and production of anti-inflammatory
cytokines such as IL-10 - CORRECT ANSWER-true
Gut homing activated T cells express the following chemokine receptor and adhesion
molecule combination - CORRECT ANSWER-CCR9; alpha4/beta7 integrin
Defects in which of the following proteins do NOT result in severe combined
immunodeficiency (SCID)? - CORRECT ANSWER-AID
Bruton's X-linked agammaglobulinemia (XLA) results from a mutation in: - CORRECT
ANSWER-Bruton's tyrosine kinase (Btk)
Patients with Wiskott-Aldrich syndrome show severely impaired responses to vaccines
such as the tetanus vaccine, which is composed of the inactivated tetanus toxin. Yet,
these patients can generate normal antibody responses to bacterial polysaccharide
antigens. This selective defect in antibody response in Wiskott-Aldrich syndrome
patients is due to: - CORRECT ANSWER-defective polarized secretion of cytokines by
CD4 T cells
Defects in LFA-1 gene lead to: - CORRECT ANSWER-Leukocyte adhesion deficiency
(LAD)
Which method is most characteristically used by trypanosomes to escape the immune
response? - CORRECT ANSWER-switching of VSGs (variable surface glycoproteins)
, Influenza virus has a segmented RNA genome. Point mutations in the influenza virus
genome is called ________(1), which causes milder and limited disease. In contrast,
antigenic changes by reassortment of the segmented RNA genome are known as
__________(2), which causes more severe disease and higher mortality - CORRECT
ANSWER-(1) antigenic drift
(2) antigenic shift
Malaria is caused by Plasmodium falciparum and Plasmodium vivax. These pathogens
are transmitted when an individual is bitten by a Plasmodium-infected mosquito. This
route of transmission: - CORRECT ANSWER-allows the parasite to avoid the normal
mechanisms blocking infections at barrier surfaces
Herpesviruses are a class of viruses that establish life-long infections in human hosts.
One herpesvirus, Herpes Simplex virus, causes recurrent cold sores in infected
individuals. Thus, in spite of a robust antiviral CD8 T cell response, these individuals still
suffer from periodic virus-induced cold sores following exposure to UV light or certain
hormones or other stressors. This antiviral CD8 T cell response: - CORRECT
ANSWER-eliminates infected epithelial cells but not infected neurons
In the type III immune response, both TH17 and ILC3 cells secrete IL17 to activate: -
CORRECT ANSWER-neutrophils
A few days after a virus infection is cleared, the majority of virus specific CD8 T cells
start to die. Death of these T cells is caused by: - CORRECT ANSWER-Fas induced
apoptosis (extrinsic pathway)
Which of the following cytokines is important to maintain T cell memory - CORRECT
ANSWER-IL-7
Effector memory T cells (Tem) can be distinguished from the central memory T cells
(Tcm) by: - CORRECT ANSWER-expression level of CCR7
The immune response is a dynamic process that initiates with an antigen independent
response, which becomes more focused and powerful as it develops antigen specificity.
Once the adaptive immune system develops, a single type of cell or immunoglobulin is
capable of eliminating any type of pathogen. - CORRECT ANSWER-False
In response to an intracellular bacterial or viral infection, effector TH1 cells,
macrophages, NK cells and CD8 cytotoxic effector cells are all recruited to the site of
infection. The coordinated recruitment of all of these cell types is orchestrated by: -
CORRECT ANSWER-the shared expression of chemokine receptors on these different
cell types
Which of the surface proteins is neither a receptor nor a co-receptor for HIV? -
CORRECT ANSWER-CD8
