Practice #6

Question 1

Optimal antigen dose in vaccine

Answer 1

Not too high not too low
High dose: will lead to tolerance clonal exhaustion, anergy and ignorance
Low dose: will lead to tolerance as well, by activation of Treg

Question 2

Adjuvant

Answer 2

substance that enhances the body immune response to an antigen
How?
1. By activating APCs and increase the expression of costimulatory molecules
2. By providing depot effect allowing more immune cells to encounter the antigen

Question 3

Examples for different adjuvants

Answer 3

Depot effect ----> Danger signal spectrum 
Natural liposomes
Aluminium mineral salts
ISCOM immune stimulatory complex 
Water/oil emulsions
Oil/water emulsions
TLR agonists
Saponins

Question 4

Subcutaneus/ intramuscular immunizaion vs. oral/ nasal immunization
Location

Answer 4

Lymph node immune response vs. mucosal immune response

Question 5

Subcutaneus/ intramuscular immunizaion vs. oral/ nasal immunization
Ag type

Answer 5

Processed Ag collected in draining lymph nodes vs. unprocessed Ag that can pass the mucosa by trans cytosis of M cells

Question 6

Subcutaneus/ intramuscular immunizaion vs. oral/ nasal immunization
Cytokines

Answer 6

DC: IL12
Th1: IFN gamma, IL2
vs.
Th2 and T reg: TGF beta

Question 7

Subcutaneus/ intramuscular immunizaion vs. oral/ nasal immunization
Abs

Answer 7

IgG vs. IgA

Question 8

Subcutaneus/ intramuscular immunizaion vs. oral/ nasal immunization
Memory cells

Answer 8

Memory cells with tissue specific migration capacity

Question 9

Subcutaneus/ intramuscular immunizaion vs. oral/ nasal immunization
Effect

Answer 9

Prevent microbes from spreading to the lood or body fluids vs. prevent microbes from spreading along the luminal barriers

Question 10

Subcutaneus/ intramuscular immunizaion vs. oral/ nasal immunization
Example

Answer 10

Hepatitis B vaccine vs. Polio virus vaccine

Question 11

Serology of HBV acute infection

Answer 11

HBSAg+ (large surface antigen)
anti HBC IgM+ (anti core antigen antibody)
anti HBS IgM+ (anti surface antigen antibody)

Question 12

Serology of HBV cured infection

Answer 12

HBSAg-
anti HBC IgG+
anti HBS IgG+

Question 13

Serology of HBV immunized patient

Answer 13

HBSAg-
anti HBC IgG-
anti HBS IgG+
Immunization is against the HBS Ag

Question 14

Whole vaccines

Answer 14

Live attanuated pathogen (by genetic modification or selection)
Efficient
Life long immunity
Not for immunocompromized pt
Ex: MMR, rotavirus, TB, varicella, polio virus

Killed pathogen (by heat, alkalyting agent, irradiation)
Less efficient (provides only humoral immunity)
Short term immunity
Less dangerous
Ex: HepA, cholera, rabies, polio virus

Question 15

Subunit vaccines

Answer 15

Toxoid (inactivated toxin)
Polysaccharide vaccine (do not evoke long term immunity since the activation of B cells is TI)

Question 16

Conjugated vaccine

Answer 16

The solution for polysaccharide vaccines in order to evoke a stron immune response.
Link the polysaccharide with a protein antigen that will evoke TD B cell activation and eventually memory.

Ex: HiB, N.meningitdis, S,pneumonia

Question 17

Contraindications for vaccination

Answer 17

1. Pregnancy
2. Fever
3. Shortening of the recommended time frame for booster vaccine is ot possible
4. Infants
5. Elderly
   possible solutions: optimize adjuvants, booster injections, increase the dose
6. Immunocompromized patients

Question 18

Herd immunity

Answer 18

If more then 90% of the population are vaccinized, it will block the disease from spreading even if 10% of the population are not vaccinized