2022 exam 3 questions

Question 1

the secondary adaptive immune response to pathogens is faster than the first adaptive immune response due to the presence of what?

Answer 1

memory cells

Question 2

the English physician Edward Jenner developed a method of prevention known as vaccination. he discovered that inoculation of individuals with ______________ prevent the disease known as smallpox.

Answer 2

cowpox

Question 3

activated B cells within germinal centers can

Answer 3

differentiate into effector plasma cells or memory B cells

Question 4

the Pfizer/BioNTech and Moderna vaccines against SARS-CoV-2, the causative agent of COVID-19 are __________ vaccines.

Answer 4

mRNA

Question 5

which is the first class of immunoglobulin secreted by plasma cells during the primary response?

Answer 5

IgM

Question 6

memory B cells are quickly activated upon a second encounter with a pathogen, producing immunoglobulins that have undergone what process?

Answer 6

somatic hypermutation and isotype switching

Question 7

the secondary immune response is primed by ________________ cells.

Answer 7

memory

Question 8

during a secondary immune response, naive B cells _______________________ if they recognize the same pathogen as a memory B cell.

Answer 8

are inhibited

Question 9

the incorporation of ______________ into vaccines helps to elicit an inflammatory response.

Answer 9

adjuvants

Question 10

the first memory T cells produced during clonal expansion are T memory stem cells, which can differentiate into what types of cell(s)?

Answer 10

central memory T cells or effector memory T cells

Question 11

which of the following represents the correct sequence of events during a mucosal immune response?

Answer 11

pathogen infection –> pathogen delivery to lamina propria –> pathogen destruction in lamina propria –> healthy mucosal tissue

Question 12

all of the following are activated in a mucosal immune response except

Answer 12

NFkB

Question 13

antibodies are important for protection during

Answer 13

both systemic and mucosal immunity

Question 14

which of the following is a cell of innate immune system and would respond to proteins during a helminth infection by secreting IL-5 to promote activation of granulocytes?

Answer 14

ILC2

Question 15

which of the following occurs in mucosal immunity but not in systemic immunity?

Answer 15

pathogens are delivered to the lamina propria through M cells

Question 16

which of the following is the correct definition of systemic immunity?

Answer 16

it is the innate and adaptive immune responses that protect most of our body

Question 17

what role does the normal microbiota play in protecting mucosal surfaces?

Answer 17

it competes with pathogens for space and nutrients

Question 18

intestinal macrophages, gut dendritic cells, and innate lymphoid cells function in the innate immune response to combat mucosal infection without inducing

Answer 18

the typical inflammatory response

Question 19

the most common immunoglobulin produced by plasma cells in the lamina propria is

Answer 19

IgA

Question 20

the main function of the MALT is to

Answer 20

centralize activation of an adaptive immune response at mucosal surfaces

Question 21

when two variants of influenza virus enter the same host cell, new viruses containing aspects of both variants can be produced in a process is known as

Answer 21

antigenic shift

Question 22

many species of bacteria have multiple ________________ that exhibit different surface molecules and thus are not recognized by the same immunoglobulins.

Answer 22

serotypes

Question 23

an extracellular pathogen that can inhibit function of the actin cytoskeleton is

Answer 23

Yersinia pestis

Question 24

the bacterial species Listeria monocytogenes escapes the phagosome after it is phagocytosed by creating holes in the phagosome membrane using

Answer 24

the toxin listeriolysin O

Question 25

a superantigen produced by bacteria can result in

Answer 25

the immune response becoming dysfunctional

Question 26

destruction of virus-infected host cells occurs primarily through the direct action of

Answer 26

cytotoxic T cells

Question 27

a survival method used by an intracellular pathogen is to avoid ______________________ fusion inside the phagocyte.

Answer 27

phagolysosome

Question 28

some bacteria perform degradation of IgA on mucosal surfaces using an IgA

Answer 28

protease

Question 29

the RNA genome of influenza virus is replicated by a RNA polymerase that does not have proofreading abilities, thus errors can be introduced, changing the surface molecule structures in a process known as

Answer 29

antigenic drift

Question 30

viruses can incorporate their viral genomes into a host cell and undergo a dormant state known as

Answer 30

latency

Question 31

severe combined immunodeficiencies often are due to the lack of which cell subsets?

Answer 31

lymphocytes

Question 32

what would be the expected phenotype of a mouse that does not express Bruton's tyrosine kinase (BTK)?

Answer 32

lack of B-cells only

Question 33

DiGeorge syndrome is caused by a missing or impaired

Answer 33

thymus

Question 34

patients with hereditary angioneurotic edema (HANE) have low levels of plasma C2 and C4 complement proteins, resulting in potentially life-threatening conditions. which protein is most commonly mutated in such patients?

Answer 34

C1INH

Question 35

human immunodeficiency virus (HIV) is a

Answer 35

retrovirus

Question 36

classical NK cell deficiency can be caused by improper hematopoiesis due to haploinsufficiency of which transcription factor?

Answer 36

GATA2

Question 37

individuals with Omenn syndrome lack which proteins from somatic recombination?

Answer 37

RAG1 or RAG2

Question 38

_____________ immunodeficiency can be due to environmental factors, such as exposure to toxins .

Answer 38

secondary

Question 39

B-cell immunodeficiencies are the most prevalent inherited immunodeficiencies because

Answer 39

inherited immunodeficiencies in innate or T cells result in significant morbidity compared to B-cell immunodeficiencies

Question 40

in Chediak-Higashi syndrome, patients have defects in proteins that control lysosomal trafficking because

Answer 40

lysosomes aren't able to fuse with phagosomes, resulting in inefficient destruction of bacteria

Question 41

reactions that occur when immunoglobulins stimulate an unwanted response following immune complex formation are called type ____ hypersensitivity reactions.

Answer 41

III

Question 42

which type of reaction occurs when a small amount of allergen is injected into the skin via an insect bite or sting or as part of testing to diagnose specific allergies?

Answer 42

Wheal and flare

Question 43

mast cell degranulation can also activate smooth muscle fiber contraction, which

Answer 43

prompts coughing, sneezing, vomiting, or diarrhea to expel a pathogen from the mucosal tissue

Question 44

delayed-type reactions caused by the activation of T cells by a foreign, but harmless, antigen are called type ___ hypersensitivity reactions.

Answer 44

IV

Question 45

inflammatory mediators, such as TNF-alpha, increase

Answer 45

migration of other immune cells to the site of infection and also inhibit pathogen division and survival

Question 46

reactions caused by the production of immunoglobulins that recognize host cell-surface molecules and target cells containing these molecules via the complement pathway or antibody-dependent cell-mediated cytoxicity are called type ___ hypersensitivity reactions.

Answer 46

II

Question 47

molecules that can specifically trigger a type I hypersensitivity response are known as

Answer 47

allergens

Question 48

ABO blood types are determined by the presence or absence of the three glycolipid antigens

Answer 48

H, A and B

Question 49

the stimulation of an immune response by an innocuous substance is called

Answer 49

hypersensitivity

Question 50

_______________ are capable of secreting inflammatory mediators such as histamine and prostaglandins and toxic molecules, including major basic protein, peroxidase, cationic protein, and a cellular neurotoxin.

Answer 50

eosinophils

Question 51

DPT vaccine

Answer 51

older vaccine diphtheria, pertussis, tetanus toxoid vaccine: inactive antigen is injected, neutralization of toxins via immunoglobulin production inactivation by formalin or heat treatment given by injection (intramuscular, thigh) IgG

Question 52

Tdap vaccine

Answer 52

newer diphtheria, pertussis, tetanus vaccine toxoid and inactivated inactivation by formalin or heat treatment booster (recommended every 10 years) given by injection (intramuscular, thigh) IgG

Question 53

Pfizer COVID vaccine

Answer 53

rapid development and production mRNA vaccine inactivated vaccines: require booster, first dose does not elicit an immune response that provides a high level of protection given by injection (arm) IgG

Question 54

Salk polio vaccine

Answer 54

inactivated vaccine: composed of killed or inactivated pathogens, formalin or heat treatment given by injection IgG

Question 55

Sabin polio vaccine

Answer 55

live attenuated vaccine: utilize pathogens that has lost its ability to cause disease but does not kill the pathogen, survives in host without causing disease closely mimics infection administered orally (swallowed) promotes IgA response over IgG

Question 56

Listeria monocytogenes

Answer 56

bacteria live in the cytosol of host cells following phagocytosis escape phagosome, avoiding destruction by the host cell uses a pore-forming toxin (listeriolysin O) to punch holes in the phagosome membrane allows bacteria to escape into the cytosol, where it is protected from phagocytes and neutralizing antibodies lateral movement, adjacent cell spreading

Question 57

mycobacterium tuberculosis

Answer 57

prevents fusion of the phagosome by targeting proteins involved in membrane trafficking and fusion coats surface and prevents docking uses protein phosphatases to dephosphorylate and inactivate the host proteins involved in these processes block acidification of the interior of the phagosome by preventing assembly of the proton pumps made by the host cell

Question 58

Neisseria spp. (gonorrhea)

Answer 58

use multiple gene copies of Opa outer membrane protein, each copy has its own expression switch allows bacteria to vary expression of Opa on the surface and avoid the host immune response express variants of their pilin gene, allowing different pili to be expressed on the bacterial surface vary sugars at ends of the lipooligosaccharide molecules found in their outer membranes block lymphocyte activation or lymphocyte effector mechanisms degrade IgA at mucosal surfaces using an enzyme

Question 59

varicella zoster

Answer 59

causes chickenpox and shingles herpes virus immune system must recognize a viral infection and destroy the infected host cell can limit antigen presentation within the host cell, minimizing CD8 T-cell activation viral latency: ability to remain dormant, needs to be reactivated

Question 60

staphylococcus aureus

Answer 60

degrade IgA at mucosal surfaces using an enzyme recurring bacterial infections bind to both MHC class II molecules and T-cell receptors stimulates a very strong nonspecific T-cell response cause inflammation superantigen blocks IgA action and the complement pathway prevents phagocytosis blocks C5 (formation of the MAC)

Question 61

hypersensitivity type 1

Answer 61

allergic response immediate, seconds granulocytes (mast cells, eosinophils, basophils) IgE leads to release of inflammatory mediators from the granulocytes Fc epsilon receptors causes symptoms of allergy such as rhinitis or anaphylaxis mast cell: expel pathogen basophils: pathogen expulsion, parasites eosinophils: secretion of inflammatory mediators (histamine, prostaglandins) and toxic molecules allergen specificity

Question 62

hypersensitivity type II

Answer 62

complications with circulatory system cell mediated, minutes classical complement pathway or antibody-dependent cell-mediated cytotoxicity IgG (can also be IgM) recognizes cell-surface molecules and destroys ex. blood transfusion reactions reactions include: opsonization in phagocytosis, activation of complement on recognized cells, activation of antibody-dependent cell-mediated cytotoxicity Fc gamma C3b recognition result in destruction of the cell through phagocytosis, lysis through action of the MAC, or destruction by NK cells

Question 63

hypersensitivity type III

Answer 63

complexes, minutes to hours phagocyte IgG (or IgM) recognize soluble antigens and form immune complexes results in the unnecessary activation of complement and activation of phagocytic cells ex. serum sickness and Arthus reaction abnormal activation of inflammatory responses and cells that attempt to clear the immune complexes disruption of normal phagocytosis

Question 64

hypersensitivity type IV

Answer 64

delayed, > 2 days no antibody delayed type cytotoxic T-cell (TD cell) caused by delayed activation of T cells by a foreign, harmless antigen ex. contact dermatitis and granulomas chronic infection APCs sensitization and effector phase induced by intracellular bacteria, viruses, fungi