immunization and vaccines Flashcards
Vaccine
preparation of a weakened or killed pathogen or portion of the pathogen’s structure
stimulates antibody production or/and cellular immunity against the pathogen
Immunization/ vaccination
Act of inoculating an individual
Naturally acquired - active
antigens enter body naturally
long term protection
Naturally acquired - passive
antibodies from mom to fetus
transient protection
Artificially acquired - active
antigens in vaccines
long term protection
Artificially acquired - passive
immune serum injection
transient protection
Uses of Artificial Passive Transfer
Pre and Post exposure prophylaxis
Reduce symptoms in ongoing diseases
Protection in immunosuppressed, neonates
Sources of Ig for Artificial Passive Immunity
blood donors (IG)
sero-positive humans to provide protection against specific pathogens ->
homologous hyper-immune sera
immunized lab animals ->
heterologous hyper-immune sera
Monoclonal antibody
Serum sickness
response against antigenic determinants of the foreign antibody when from a non-human source or human with different allotype
Transmission of blood borne pathogens
Contaminated blood
Immuno-suppression
blocking/neutralizing pathogens (down regulation of B cell activation, antibody feedback)
Herd Immunity
For infections that depend on human transmission vaccinating the majority of the population reduces the source of infection
Inactivated vaccine
(killed) whole cell
Must maintain antigenicity, but does not replicate
produces IgG
longer lasting & more effective
Live attenuated vaccine
(weakened)
Capable of replication: reduced/lost virulence
Advantage:
Live vaccine strain can be spread to others -> good to achieve herd immunity
Disadvantage:
might be transmitted to immunosuppressed individuals
produces IgG, IgA
Subunit vaccines
Capsular
Conjugate vaccines
Recombinant
Synthetic
