VACCINE IMMUNOLOGY Vaccination vs Immunisation Vaccination is the
- Slides: 49
VACCINE IMMUNOLOGY
Vaccination vs. Immunisation Vaccination is the term used forgiving a vaccine - that is the process of introducing a substance to a host (i. e. Injection or droplets). Immunisation is the term used for the process of both getting the vaccine and becoming immune to the disease as a result of the vaccine. • Vaccination – named from the use of vaccinia, or cowpox, to induce immunity to variola (smallpox) in humans.
Early history of vaccination • 7 th Century - Indian Buddhists drank snake venom (for snakebites). • 10 th/17 th Century China – “inoculation or variolation” (for smallpox). • Variolation (inoculation)- introduced to Europe from Turkey in 1721.
History of vaccination Lady Mary Montague, who witnessed variolation in Istanbul, came back UK and had her daughter inoculated. She then advised the royal family to have their children inoculated. As a safeguard, the procedure was first tested on six prisoners (death penalty). All survived and pardoned. Royal children inoculated and survived and variolation became fashionable in Europe.
Edward Jenner
History of vaccination 14 May 1796 Edward Jenner used material from a cowpox pustule on the hand of Sarah Nelmes to vaccinate James Phipps (8 yr boy). 1 July 1796 Jenner used virulent smallpox matter to challenge James Phipps. Experiment successful: Phipps survived many subsequent exposure over 20 yrs
Smallpox vaccination • 300 million people died of smallpox in the first three-quarter of the 20 th Century. • Smallpox eradicated in 1979 because of mass vaccination programme
Goals of vaccination • In individuals - prevention of disease • In populations - eradication of disease
Immunisation Schedule in Saudi arabia *BCG (Bacillus Calmette-Guérin) is the current vaccine against TB.
Vaccination saves lives Infant vaccination programmes have saved approx. 3 million deaths worldwide annually Hepatitis B (900, 000), measles (900, 000), tetanus (400, 000), H. influenzae (400, 000), pertussis (350, 000), yellow fever (30, 000), diphtheria (5, 000) polio (800)
Major diseases that could be prevented by no effective vaccines yet
Types of immunisation 1. Active Administration of antigen (modified infectious agent or toxin) resulting in active production of immunity eg. antibodies 2. Passive Administration of antibody-containing serum or sensitised cells
Active • natural (unintended) • deliberate - vaccination Passive • Placental transfer (Ig. G) • colostral transfer (Ig. A) • transfer of human Ig or cells
A good vaccine should be: • Safe - no significant side effects • Effective, and preferably long-lasting • Stable in storage • Cost-effective for the target population
Types of vaccines 1. Live attenuated vaccines 2. Inactivated vaccines (killed) 3. Subunit vaccines
Types of vaccines Live attenuated Measles, mumps, rubella, polio, BCG (TB) Inactivated Heat killed organisms typhoid, cholera, pertussis Toxoid (inactive form of toxin, capable of inducing Ab to toxin which causes disease). eg. Diptheria, tetanus
Types of vaccines Subunit • Polysaccharide (PS), conjugate PS eg. Pneumococcal PS, meningococcal PS • Recombinant DNA products / purified proteins eg. hepatitis B, influenza proteins
Live vaccines Advantages • single, small dose • given by natural route • local & systemic immunity • resembles natural infection Disadvantages • contaminating virus, • reversion to virulence • inactivation by climatic changes
Inactivated (killed) vaccines Advantages • safe • stable, so for each batch the safety and efficiency is known Disadvantages • multiple doses and boosters needed • given by injection - unnatural route • high antigen concentration needed • variable efficiency
Polio Vaccines as a example • 1958, killed (inactivated) virus ‘Salk’ vaccine introduced, but cannot replicate in cytosol to produce ‘endogenous’ peptides for presentation to CD 8+ T cells • 1962, Switched to oral live attenuated virus ‘Sabin’ (OPV) , more potent, but can rarely revert back to a virulent strain causing vaccine associated paralytic polio (VAPP). • 2004, changed to inactivated polio vaccine
Safety Live vaccines Killed vaccines Immunogenicity Single proteins
Principles of Vaccination • To induce a primary response without direct exposure to the infective pathogen • To induce immune memory so that a more rapid and efficient protective response are induced if the original pathogen is ever encountered again
Vaccination - like a minor infection at an epithelial surface Antibody Tc-dependent M activation Cytotoxic T cells
T cell-mediated immunity
Function of Antibody -1
Function of Antibody -2 Opsonisation Ig. G 1, Ig. G 3, Ig. G 4, Ig. A
Function of Antibody -3 Antibody-dependent cellular cytotoxicity(ADCC) Ig. G 1, Ig. G 3
Function of Antibody -4 -Activation of the complement cascade Ig. G Ig. A Ig. M
The affinity as well as the amount of antibody increases with repeated immunization © 2001 by Garland Science
Primary vs Memory response
Adjuvant immunogen + adjuvant = enhanced response • To hold the antigen and release it slowly • local inflammation, attract immune cells, eg. APC • enhance Ag uptake, processing and presentation by APC • promoting local cytokine production
Adjuvants • Alum. hydroxide suspension • Pertussis toxin - mixed with Diphtheria and Tetanus toxoid DTP triple vaccine
Polysaccharide vaccines Encapsulated bacteria Against Hib, menigococcus, pneumococcus. Capsular PS, virulence factor
Immune response to PS vaccines
Limitations of polysaccharide vaccines 1. T cell independent antigen: • Stimulate B cell for antibody production without T-cell help 2. Poorly immunogenic in infancy (Not effective in young children) 3. No memory But Effective in older children and adults
Making PS Ag T-cell dependent - conjugate vaccines � PS conjugated to a carrier protein to create a “T cell antigen” Tetanus toxoid polysaccharide • T-cells recognise the protein (eg. TT) and activated • Activated T cells provide signals (eg cytokines) to ‘help’ B-cells to produce antibodies
Conjugate polysaccharide vaccines Protein Ag attached to PS allow T cells to help PS-specific B cells. © 2001 by Garland Science
Conjugate polysaccharide vaccines 39 © 2001 by Garland Science
Immune response to Conjugate PS vaccines
Advantages of conjugate vaccines • More immunogenic than PS vaccines • Effective in young children as well • T cell involvement and Immunological memory • Long-term protection
Limitation of conjugate vaccines � Limited serotype coverage � Increase in non-vaccine serotypes after vaccination � expensive
Herd Immunity • Unimmunised individuals are also protected against a disease as well as most others immunised in the community. • Herd immunity needs substantial coverage of population by vaccination. • If substantial portion of community not immune then introduced virus can circulate and cause disease in nonimmune group.
Passive Immunisation • Provide antibodies - whole serum or immunoglobulin (mainly Ig. G). • Provide immediate protection, eg rabies, tetanus, diphtheira. • No long term protection.
Haemolytic disease in the newborn 46 Rh. D- mother with Rh. D+ fetus can develop anti-Rh antibodies and cause haemolysis to the newborn and subsequent pregnancy.
Antenatal and postnatal administration of anti. Rh. D immunoglobuin to Rh. D- mother can prevent haemolysis in the newborns
SUMMARY
The end
- Ranjana kumar
- Antigen antibody
- Hematopoiesis wikipedia
- Nature reviews immunology
- Journal of experimental medicine
- Abbas basic immunology
- Server medical art
- Nature reviews immunology
- Assisting in microbiology and immunology
- Cellular and molecular immunology
- Fea course
- Immunology ppt template
- Pals immunology
- Abbas basic immunology
- Fraunhofer institute for cell therapy and immunology
- Nature reviews immunology
- Elsever
- Guangde tu
- Kuby immunology
- Diploma in immunology
- Phagocyte
- Avidity in immunology
- Trends in immunology
- Ras
- Braverman reproductive immunology
- American academy of allergy asthma and immunology 2018
- Tumor immunology
- Pcams immunology
- Japanese encephalitis vaccination sydenham
- Mandatory vaccination
- Vaccine dose schedule
- Dog vaccination perry county
- Niccolo paganini fingers
- Vaccination xard
- Conclusion of immunization
- Poultry vaccination schedule
- Defaulter vaccination schedule
- Bankeryds vårdcentral influensavaccin
- Vaccination a la defense
- A vaccination for smallpox was developed in 1796 by ____
- Vaccination schedule in palestine
- Vaccination bruxelles
- Diseases with vaccines
- Rabies vaccine ppt
- Vaccine investment strategy
- 7 rights of vaccine administration
- Vaccine for meningitis
- Tetadif td vaccine
- Smallpox vaccine needle
- Grade californias vaccine