Exam: Vaccines

• 1 Active

  ongoing process

  proteins or antigens will activate an immune response

  develop antibodies

  2 Passive

  receive antibodies / protective qualities from others.

  mother → baby (antibody)

  • herd immunity (protective qualities)
• Herd Immunity = based on a majority of immune individuals in the vicinity

  -resistance of an infectious attack by a large population (pop^n) or members of a group / community

  solid immunity = must have all vaccine requirements (series)
• Criteria for Herd Immunity

  1 agent must be a single host species

  2 transmission of disease must relatively be through direct contact

  3 immune individuals must have solid immunity

  4 pop^n must be randomly mixed

  5 a certain % of pop^n must be vaccinated (solid)

  R0 = measure of infectivity 
• Vaccine Development

  Vaccine = a dose of either whole of subunits of a pathogen

  • induce active immunity

  proteins = antigens = recognized by antibodies
• Reasons to use bacteriacan acquire DNA from other sources than parents (vertical evolution + conjugation + transformation + transduction)plasmid = can transfer between organism

  haploid = everything expressed (no dominance)
• Horizontal Gene Transfer

  Conjugation = exchange DNA through pilli

  Transformation = break open & releases DNA, 2nd organism takes in DNA (incorporated into genome)

  Transduction = virus replicates within
• 1 "live" attenuated vaccine (LAV) 

  = best immunity / protection

  * usually does not require a booster

  "whole" "active" pathogen capable of replicating

  • prepared in nonhuman cells (in-vitro) or chick embryos
• 2 Killed or Inactive

  = chemically or heat inactive pathogen

  cannot replicate

  • pathogen is still intact

  * shorter immune lifespan (requires a booster or series (solid immunity))
• 3 Toroid Vaccine

  = prevent bacterial infections

  caused by the release of toxins (proteins) → antigens

  vaccine → inactivated form of the toxin

  • requires booster
• 4 Subunit / Conjugate

  subunit = contains small pieces of a pathogen

  known to direct an immune responser

  conjugate = pieces of bacteria / viruses / subunits combined with a carrier protein

  • causes a strange response
• Restriction Enzyme

  "Restriction Endonuclease"

  naturally found in bacteria and archaea

  used to cut up foreign DNA (molecular scissors)

  • enzyme that cuts DNA at a specific sequence (recognition sequence)

  the "cut" occurs at a specific point of a sequence (restriction cut sequence)
• Sticky Ends

  "stick back together easily" 

  = overhanding

  Ligation

  • enzymes are called DNA ligase (molecular gene)
• Nonsticky Ends

  = blunt ends

  ligation not impossible but less efficient 

  synthetic biology

  allows us to cut and paste

  develop or modify genes with restriction enzyme recognition sites

  sticky ends allow for easily shuffling of genes

  • usually into plasmid
• Plasmid

  extracurricular DNA

  circular DNA in nature

  easily manipulated

  easily transferrable to other organisms

  cut a plasmid open at restriction sites (cloning sites)

  ligate entire genes

  transform plasmid in bacteria

  • gene of interest (GOI) is expressed
• General Biochemistry (mRNA Vaccine)

  transcription = nucleus

  * ds DNA

  translation = ribosomes

  * ss RNA

  protein = cytoplasm

  mRNA = messenger RNA
• Creating mRNA VaccinesDNA + plasmid = in-vitro translation = enzyme + buffer

  Biological Mechanism of mRNA Vaccine

  transient = get broken down