Vaccines

Question 1

the memory response can be so effective there is no

Answer 1

prodrome

Question 2

what does vaccination do

Answer 2

primes the immune response without exposure to pathogenic agent

Question 3

herd immunity

Answer 3

sufficient immune members of a population limit spread of a pathogen in a population

Question 4

vaccines are composed of

Answer 4

whole pathogenic organisms or antigens from pathogens

Question 5

lymphatic system

Answer 5

returns lymph back to circulation into the subclavian veins

Question 6

lymph nodes

Answer 6

sample antigens from the lymphatics and display to lymphocytes (secondary lymphoid tissue)

Question 7

spleen

Answer 7

performs a similar function of sampling antigens for the blood (secondary lymphoid tissue)

Question 8

leukocytes are generated in

Answer 8

the bone marrow

Question 9

leukocytes are educated

Answer 9

for self vs non-self discrimination in the bone marrow or the thymus (primary lymphoid tissues)

Question 10

two arms of the adaptive immune response

Answer 10

humoral immunity - B cells
cell-mediated immunity - T cells

Question 11

humoral immunity

Answer 11

B cells
extracellular targets
antibodies secreted into the serum
binds to targets and directs effector responses
the major outcome of most vaccines

Question 12

cell-mediated immunity

Answer 12

T cells
intracellular antigens
eliminates infected or damaged cell

Question 13

clonal selection theory

Answer 13

education/deletion in the bone marrow or thymus removes auto-reactive cells
binding a specific antigen stimulates clonal proliferation to make a population of B or T cells expressing the same receptor

Question 14

B and T cells diversity is

Answer 14

encoded in the germline and expressed by recombination

Question 15

BCR recombination

Answer 15

diversity of immunoglobulin generated by recombination of V, D and J segments
requires RAG1/2 - lymphoid specific recombinase

Question 16

heavy chains

Answer 16

43 V, 21 D, 6 J = 5658 combinations

Question 17

light chains

Answer 17

have 204 or 165 different combinations

Question 18

terminal deoxytransferase

Answer 18

add non-templated additional nucleotides at each junction to increase diversity

Question 19

b cells encounter antigen and T cells in

Answer 19

lymph nodes

Question 20

how do B cells encounter antigen and T cells in lymph nodes

Answer 20

antigen from the periphery travels to the lymph nodes in the lymph
follicles contain FDCs and B cells
FDCs trap antigen
B cells continually circulate to different lymph nodes and sample antigen
B cell that finds antigen move to the paracortex (T cell zone)

Question 21

activated B cells form a

Answer 21

germinal center (GC)

Question 22

germinal center

Answer 22

sites of somatic hypermutation (SMH) and class switching
both require activation-induced cytidine-deaminase (AID)

Question 23

somatic hypermutation increases

Answer 23

affinity and diversity of antibody responses

Question 24

class switching changes

Answer 24

the effector functions of antibodies (new Fc regions)

Question 25

types of B cell antigens

Answer 25

repetitive antigens can activate B cells if there is TLR or complement bound to the antigen no co-stimulation (TLR, complement, or T cell) leads to B cell anergy (absence of response) TD antigen, TI-1 antigen, TI-2 antigen

Question 26

qualities of a good B cell antigen

Answer 26

non-self large - many epitopes chemically complex can be degraded and presented on HLA (T-dependent) protein >> carbohydrate >> lipid

Question 27

antibodies link _____ with _____

Answer 27

link antigen recognition (Fab) with specific effector functions (Fc)

Question 28

antibody-dependent enhancement of infection

Answer 28

non-neutralizing antibodies bind (especially targeting different serotype) bind to virions Fc portion of IgG binds to Fc receptors on monocytes low pH in the endosome leads to fusion, entry and subsequent replication second infection with dengue leads to worse disease (hemorrhagic fever)

Question 29

antibody-dependent enhancement of infection is especially observed in

Answer 29

flaviviruses dengue, zika, west nile, yellow fever

Question 30

adaptive immunity - cytotoxic T cells

Answer 30

express CD8 and recognize antigen in the context of HLA class I if cytotoxic T cell recognizes its cognate antigen it will attempt to kill the cell

Question 31

preformed granules contain

Answer 31

perforin and granzyme B

Question 32

granzyme B stimulates

Answer 32

apoptosis by the intrinsic pathway (damaging mitochondria)

Question 33

Fas ligand will

Answer 33

stimulate apoptosis by the extrinsic pathway (signal from another cell)

Question 34

B cell epitopes must be

Answer 34

on the surface of the antigen

Question 35

T cell epitopes can be

Answer 35

anywhere in a protein sequence

Question 36

are there more T or B cell epitopes available in a pathogen

Answer 36

T cell

Question 37

what is common for B cell epitopes

Answer 37

antigenic drift

Question 38

antigenic drift for T cell epitopes is

Answer 38

uncommon and likely represents a higher genetic barrier

Question 39

active immunity (viral) vaccine strategies

Answer 39

attenuation inactivation fractionation cloning

Question 40

inactivated vaccines

Answer 40

whole viruses or bacteria that are inactivated using radiation, heat or chemicals (formaldehyde, formalin) -prevents replication but maintains antigenicity -do not infect cells - mostly humoral response -requires boosting

Question 41

attenuated vaccines

Answer 41

whole organism weakened or adapted to growth in non-human cells -less virulent and less replication -mild to no disease symptoms -infects cells - humoral and cell mediated response -boosting not often required

Question 42

toxoid vaccines

Answer 42

bacterial exotoxins purified from culture -toxins inactivated with chemical treatment (formaldehyde) -stimulate neutralizing antibody responses -diphtheria and tetanus exotoxins

Question 43

recombinant subunit vaccines

Answer 43

generate antigen in yeast culture and purify -requires cloning antigen that generates a protective response -stimulate neutralizing antibody responses (HBV and Shingrix)

Question 44

virus-like particles (VLP)

Answer 44

viral capsids self-assemble in a concentration-dependent manner some viral capsids do not require viral genomes - form non-infectious virus-like particles

Question 45

HPV vaccine

Answer 45

VLPs stimulate protective antibodies responses prevents cervical and some esophageal cancer and genital warts

Question 46

genetic vaccines and the strategies

Answer 46

gene encoding an antigen into human cells strategies: DNA on a plasmid, mRNA, modified virus vector

Question 47

for genetic vaccines DNA and RNA require a

Answer 47

platform allowing entry into cells, such as liposomes or electroporation

Question 48

genetic vaccines can generate

Answer 48

humoral or a cell mediated response

Question 49

COVID-19 vaccine

Answer 49

mRNA lipid nanoparticle (LNP) taken into cell escapes the endosome ionizable lipids are uncharged at neutral pH and positive charge at low pH contributes to disruption/fusion/payload delivery