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68 Cards in this Set
- Front
- Back
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What are the two basic types of Vaccination?
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Passive and Active Immunizations
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What is Passive Immunization?
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the intent is not to activate the individual's immune system, but rather to introduce protective immune cells or molecules that were generated by active immunization in another organism (Ab to snake venom)
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What is Active Immunization?
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refers to introduction of an antigen (a live, live-attenuated, or killed organism or a component of the organism) that generates an active immune response to the antigen leading to protective immunity
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What is Adjuvants?
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A prerequistite fot a good immune response is inflammation
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How is Adjuvants used?
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Adjuvants are combined with vaccines to aid in the immune response to the vaccine.
* Concentrate vaccine (other than live-attentuated) at site of introduction to limit spread - An antigen is easier to attack by the immune system if it is all in one palce (e.g. Proteins) |
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What does Adjuvants induce?
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Non-specifically induces inflammation at site of introcution
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What type of inflammation does adjuvant produce?
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Antigen independent inflammation
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2 examples of Adjuvants
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Experimental Immunology and Human Use- Alum and MF59
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What is Experimental immunology?
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Freund's complete: an emulsion of killed mycobacteria and mineral oil (Very strong- can be fatal by septic shock)
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What are the two types of Human Use?
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ALum and MF59
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What is Alum?
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a form of aluminum hydroxide
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What is MF59
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an emulsion of squalene, oil, and water
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What type of side effects does Alum and MF59 produce?
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both weaker, but safe with no side effects.
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What are the four normal forms or types of vaccine?
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- Killed or inactivated vaccines
- Live attenuated vaccines - Subunit vaccines - Conjugate vaccines |
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What is Killed/inactivated Vaccines?
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- The ability of a virus or bacteria to carry out a productive infection.
- The bacteria is killed and the virus is inactivated, but each can still stimulate the immune system |
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How is a killed/inactivated vaccine --the ability of a virus or bacteria to carry out a productive infection is removed?
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- Chemical treatment (formalin)
- Heat killing (autocalve) - Irradiation (create unrepairable nucleic acid damage) |
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What are the benefits of a killed/inactivated vaccine?
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safer than live attenuated vaccines
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What are the common examples of Killed/inactivated vaccines?
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-Influenza (virus)
-Rabies -Salk polio vaccines |
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What are the problems of Killed/inactivated vaccines?
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- Large quantities of inactivated pathogen needed
- Suitability of genome for irradiation - health hazards of chemicals invovled in killing/inactivation |
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What is a Live attenuated Vaccine?
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The ability of a virus or bacteria to cause disease (different from ability to cause an infection) is removed by manipulation of the genome
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How is Live attenuated vaccine done?
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- Forced evolutio of a virus in culture
- Direct manipulatio nof viral or bacterial genome by molecular biological techniques. |
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In Live Attenuated Vaccine, The steps of Forced evolutio by growth in non-human cells
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1. The pathogenic virus is isolated from a patient and grown in human cultured cells.
2. The cultured virus is used to infect monkey cells 3. The cirus acquired many mutations that allow it to grow well in monkey cells. 4. The virus no longer gorwos well in humna cells ( it is attenuated) an can be used as a vaccine. |
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What are the recombinant techniques to attenuate the virus or bacteria?
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- All genes involved in virulence (disease), but not required for growth are removed
- Same technique can be used for bacteria. Many have virulence genes located in a plasmid separate form the genome. |
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What are the benefits of Live attenuated vaccine?
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Best at introducing an immune response
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What are the common examples of Live attenuated Vaccine?
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- Measles (MMR)
- Mumps (MMR) - Sabin Polio - Yellow Fever |
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What are the problems in production for Live Attenuated Vaccine?
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Reversio mutant (e.g. Sabin Polio vaccine)
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What are subunit Vaccines?
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Humoral immune responses are typically made against protein/lipids on teh exterior of virus particles or bacterial capsules
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What are the 2 types of subunit vaccines?
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-Protein subunit vaccines
-Polysaccharide subunit vaccines |
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What is a protein subunit vaccine?
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The genes for proteins are isolated and their encoded proteins are produced in large quantities by recombinant techniques
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What is a polysaccharide subunit vaccines?
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The capsule of pathogenic bacteria are purifed and used as a subunit vaccine
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What happens in a Protein Subunit Vaccine?
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- The viral gene encoding capsid protein is used to create large purified quantities of the capsid protein for use as a vaccine
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What are examples of Subunit Vaccines?
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HBV vaccine (HBsAG) (Protein subunit)
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What was the first vaccine that was first licensed vaccine in the US produced by recombinant DNA technology?
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Recombinant hepatitis B vaccine
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What are the problems in production for subunit vaccines? --polysaccharide subunit
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Polysaccharide subunit elicit a T-independent response that is poor in children under 18 months.
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What are toxoids?
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Toxoids ar ehte most successful of bacterial subunit vaccines.
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How are Bacterial toxins inactivated?
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Bacterial toxins are inactivated by treatment with formalin. The toxin loses its pathogenicity but the protein is sitll capable of generating an immune response
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List the Examples of Toxoids
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- Tetanus toxoid (tetanus) and Diphtheria toxoid (diptheria) are classic examples.
- DTP - DTaP |
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What is DTP?
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combination of diptheria and tetanus toxoids along with killed preparation of bacterium Borhetella pertussis
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Waht is DTaP?
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combination of diphtheria and tetanus toxoids along with a preperatio of acellular pertussis (aP) component
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What does aP component contain?
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aP contains inactivated pertussis toxin and one or more pertussis antigens (including hemagglutinin, pertactin, and fimbrillar antigen)
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Whare are the newer formulation or mechanisms for introduction fo subunit vaccines?
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- DNA vaccines (Subunit vaccines)
Other subunit Vaccines: - DNA vaccines - Viral vectors - Conjugate vaccine |
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What is DNA vaccines?
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Plasmids containing a complementary DNA (cDNA) encoding a protein antigen is inoculated into subject.
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What are the steps to DNA vaccines?
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Cells take up the DNA and begin to express the encoded protein, which can then be presented to T cells.
- Then plasmids grown in bacteria are rich in unmethylated CpG nucleotides that are recognized by TLR9 (patten recognition receptors) on macorphages and other cells; thus inducing an innate immune response which will enhance the adaptive immune response - APC such as dendritic cells are removed and transfected with a cDNA containing plasmid. The cells are then reintroduced into the subject to present the expressed protein from the plasmid |
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How is DNA vaccines introduced:?
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DNA complete with a promoter and encoding a single protein from a pathogen is used
- introduced into whole organism - introduced into dendritic cells removed form subject, then returned. |
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What are viral vectors?
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Viral genomes are modified to include the expression of a protein of interest form the pathogen to be vaccinated again.
* Recombinant virus acts as a live attenuated vaccine (causing more robust activation of immune response) even though only some of the genes expressed are from the pathogen of interest). |
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What are conjugate vaccine?
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A method for making a T independent subunit vaccine into a T dependent vaccine
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What does the viral/bacteria target? in Conjugate vaccine?
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Viral/bacterial target is fused or conjugated to a harmless but immunogenic protein that elicits T cell dependent response
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What are examples of Conjugate Vacccine
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H influenza B
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What are the problems in production?
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None. No negative effect
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The route of vaccination--- through the intestines and ENT
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- immune responders in intestines and ENT regions often induce and provide local, rather than systemic, memory and defense.
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The route of vaccination thought skin/bloodstream
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Pathogen entry through skin/bloodstream is more likely to induce a systemic response/memor (as in IM injections) which may not protect from entry through ENT or intestines
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Most infectious agents enter though?
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Most infectious agents enter tthe body through eating or breathing (nose and mouth)
However, most vaccination are intramuscular or subcutaneous |
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What are the new vaccines route of vaccination
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New vaccines are nasal sprays or oral.
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Childhood Vaccination: Difficulties in immunizing infants
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- Poor T independent antibody production
- Lower antibody responses to T depdendent protein vaccines - Short lived antibody responses to vaccines - inhibitory effect of maternal antibodies - altered T cell responses |
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In childhood vaccination: What does Poor T independent antibody production mean in a child?
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• Splenic, marginal zone B cells are vital responders to blood borne T-independent polysaccharide antigens.
- The architecture of the spleen is not developed until near 2 year, including the MZ - Therefore, these specific B cells may not exist or be limited in their response to T independent antigens prior to 2 years of age. B cells may not respond |
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In childhood vaccination: What does Lower antibody responses to T independent protein vaccines mean in a child?
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• Germinal centers are delayed in appearance compared to older children
- Unknown reason but may involve: Follicular dendritic cell activation or migration, other deficiencies in lymphocyte activation |
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What does Short Lived antibody responses to vaccines mean in a child?
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Plasmablasts form appropriately, but fail to survive as long as in older children/adults.
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What does Inhibitory effect of maternal antibodies mean in a child?
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• Maternal Abs will inhibit (out compete) infant Ab production, but not T cell responses. Eg: measles vaccine
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What does Altered T cell mean in a child?
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Neonatal dendritic cells to the same antigens. Infants show Th2 skewed responses
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What happens when there are barriers in childhood vaccines?
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The many potential barriers to infant vaccination lead to the use of multiple doses and boosters
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What vaccines induce the best response for a child?
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Live attenuated vaccines induce the best response in infants to other vaccine types.
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What is Herd Immunity?
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If the vast majority of a population is vaccination/immune to a pathogen, then there are fewer individuals that can become infected and expose those that are also not immune.
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What happens when declining vaccination rates?
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• Declining vaccination rates in some states are leading to an increase in cases of: Measles, Whooping cough, etc.
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What are some common side effects of vaccines (DTAP)?
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Tenderness, pain, redness, swelling at site of injection-
-Most children become drowsy, some may become fussy - Up to 5% may get a fever over 101F |
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When does vaccine reaction occur?
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- Reaction usually occurs only after the 4th or 5th shot
- Reaction usually occurs within 2 days of shot. |
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What are the "fever" concerns after vaccination?
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• Up to 5% may get a fever over 101F
o 1 in 3,000 of these may have a fever of greater than 104 F o Of these 1 in 14,000 may have convulsions caused by the fever only. These are transient and almost all recover completely with no lasting effects. o The fever is caused by the immune response to the vaccine/adjuvant and not other additives/preservatives. |
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What about vaccines and autism adn the preservatives of thimerosal?
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• Evidence from several studies examining trends in vaccine use and changes in autism frequency does not support such an association
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Admission to daycare or school re: vaccines
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• Every state has a requirement for at least the first 3 DTaP shots for daycare.
• Most state have a requirement for DTaP, Td, or Tdap for middle school and high school enrollment. |
