Primary and Secondary Ab responses

Question 1

What does the generation of Memory B cells allow for?

Answer 1

• secondary humoral immune response top antigen

Question 2

Lag phase of primary antibody immune response

Answer 2

• Ag recognized by naïve B cell
• may get T cell help
• starts making antibody

Question 3

Log phase of primary antibody immune response

Answer 3

• Ab concentration increases as more plasma cells appear

Question 4

Plateau phase of primary antibody immune response

Answer 4

• steady state between Ab synthesis and Ab degredation

Question 5

Decline phase of primary antibody immune response

Answer 5

• Ab degradation exceeds synthesis

Question 6

Primary antibody immune response

Answer 6

• seroconversion occurs
• > in general it may take one to two weeks (one week min) before we detect antibody following primary exposure or first vaccination
• IgM major class is produced, but does not persist
• lag phase, log phase, plateau phase and decline phase of antibody

Question 7

Seroconversion

Answer 7

• reflects a primary antibody response

- serum converts from no detectable antibody to detectable antibody

Question 8

Secondary (anamnesthic) antibody response

Answer 8

• lag phase is shorter
• log phase more rapid and higher
• decline phase not as rapid and Ab can persist for months, to years or lifetime
• for animistic antibody response raise in Ab level within a day or two
• IgG major class produced and antibody persists

Question 9

Assume we are looking at a response to a vaccine.. And
that antibody at a certain level is protective: Will one see an animistic response if boost after antibody level very low?

Answer 9

• YES

Question 10

Rabies Vaccine in Dogs

Answer 10

• considered protected after 28 days!
• boost at one year after the first vaccine
• > after that depends

Question 11

Why might we see seroconversion to a particular

antigen (Antigen X on a microbe) and later not be able to detect any antibody to antigen X?

Answer 11

• antibody has a half life
• > amount of Ab to a particular Ag may drop below level of detection (could still have memory cells)
• this can happen if there is no more, or insufficient continued or repeated antigenic stimulation to ensure that

Question 12

What do high IgM titers correlate with?

Answer 12

• recent exposure to antigen

Question 13

Sterile Immunity

Answer 13

• the immune response eliminates the pathogen

Question 14

Protective immunity

Answer 14

• the immune response prevents the disease, but may not eliminate the pathogen