Vaccines work by increasing resistance to infection and improving general health. There are different types of vaccines including live attenuated, inactivated, toxoid, subunit, and DNA vaccines. DNA vaccines offer advantages over traditional vaccines as they use only DNA from pathogens and stimulate both antibody and cellular immunity without risk of infection while not requiring refrigeration.

1. Conventional and Genomic
Vaccines Products

2. WhatVaccines do:WhatVaccines do:
Increase Resistance to InfectionIncrease Resistance to Infection
There are many ways to improveThere are many ways to improve
general health:general health:
1. Proper nutrition,1. Proper nutrition,
2. Exercise,2. Exercise,
3. Healthy lifestyle,3. Healthy lifestyle,
and…and…
4. Vaccination

3. WhyVaccination?
Vaccines control diseases and
can protect individual animals
from illness and death.

4.  A vaccine is a biological preparation that
provides active acquired immunity to a
particular disease.
 A vaccine typically contains an agent that
is similar to a disease-causing
microorganism.
 It is often made from weakened or killed
forms of the microbe (its toxins or one of
its surface proteins).

5.  It stimulates the body's immune
system to recognize the agent in the
form of risk, destroy it, and keep a
record of it, so that the immune
system can more easily recognize
and destroy any of these
microorganisms that it later
encounters.

6.  Vaccines can be prophylactic (example: to
prevent the effects of a future infection by any
natural pathogen OR therapeutic (example:
vaccines against cancer are also being
investigated).
 Immunization or Vaccination: A procedure
designed to increase concentrations of
antibodies and/or effector T-cells which are
reactive against infection (or cancer).

7. DifferentTypes ofVaccines
1. WeakenedVaccine
(Modified Live)
2. Inactivated (Killed)Vaccine
3. ToxoidVaccine
4. SubunitVaccine

8. Weakened (Modified Live)
Vaccines
Produced by weakening a live microorganism or
removing it’s disease-causing ability.
Advantages Disadvantages
- They produce a large
immune response
- Have to receive the
vaccine once or twice.
- They have to be kept in
special conditions, like
refrigeration.
- They can mutate and
might cause the disease.

9. Inactivated (killed)Vaccines
These vaccines are produced
by killing the infectious agent.
Advantages Disadvantages
- They do not have to
be refrigerated.
- They will never come
back to life and cause
the disease.
- They usually require
booster shots because
they only weakly
stimulate the immune
system to make
antibodies.

10. Limitations To Traditional Vaccines:
1. Can not grow all organisms in
culture
2. Expense
3. Insufficient attenuation
4. Reversion to infectious state
5. Need refrigeration
6. Do not work for all infectious
agents
7. Immature immunity for
infants/children.

11. New Generation of Vaccines:
• Recombinant DNA technology is being used to
produce a new generation of vaccines.
Virulence genes are deleted and organism is still
able to stimulate an immune response.
Live nonpathogenic strains can carry antigenic
determinants from pathogenic strains.
If the agent cannot be maintained in culture, genes
of proteins for antigenic determinants can be cloned
and expressed in an alternative host e.g. E. coli.

13. INTRODUCTIONINTRODUCTION
DNA vaccine is DNA sequence used as a
vaccine.
This DNA Sequence code for antigenic
protein of pathogen.
As this DNA inserted into cells it is
translated to form antigenic protein. As
this protein is foreign to cells, so
immune response raised against this
protein.
In this way, DNA vaccine provide
immunity against that pathogen.

14. DNA vaccinesVsTraditional vaccinesDNA vaccinesVsTraditional vaccines
DNA vaccines Traditional vaccines
 Uses only the DNA from
infectious organisms.
 Avoid the risk of using
actual infectious
organism.
 Provide both Humoral &
Cell mediated immunity
 Refrigeration is not
required
 Uses weakened or killed
form of infectious
organism.
 Create possible risk of
the vaccine being fatal.
 Provide primarily
Humoral immunity
 Usually requires
Refrigeration.

15. HOW DNAVACCINE IS MADE
Viral gene
Expression
plasmid
Plasmid with foreign gene
Recombinant DNA
Technology

16. Bacterial
cell
Transform into bacterial cell
Plasmi
d DNA

17. Plasmid DNA get Amplified

18. Plasmid DNA
Purified
Ready to use

19. ADVANTAGES
1. Produce both Humoral & cell mediated
immunity
2. Focused on Antigen of interest
2. Long term immunity
3. Refrigeration is not required
4. Stable for storage

20. DISADVANTAGES
1. Limited to protein immunogen only
2. Extended immuno stimulation leads to chronic
inflammation
3. Some antigen require processing which
sometime does not occur.

21. Vaccine preventable diseases
Diphtheria Tetanus Whooping cough
Meningitis Hib, Strep, Neisseria
Measels
Polio

22. Principles ofVaccination
•Protection from infectious disease.
•Usually indicated by the presence of
antibody.
•Very specific to a single organism.

23. Types ofVaccination
• Active:
Protection produced by the person's own immune
system, longer time and may be long lasting.
• Natural : eg – Infection
• Artificial : eg –Vaccination
• Passive: Protection transferred from another person
or animal,Temporary wanes out by time.
• Natural,
Examples: IgG crossing placenta to protect fetus
Antibodies acquired by baby through breast milk.
• Artificial
Examples:Treatment with antiserum, antitoxin.

24. Monoclonal antibody
• Derived from a single type, or clone, of
antibody-producing cells (B cells)
• Antibody is specific to a single antigen or
closely related group of antigens
• Used for diagnosis and therapy of certain
cancers and autoimmune and infectious
diseases

25. Types of Active vaccines
•Living attenuated; virus or
bacteria
•Killed or Inactivated; Whole
(Virus or Bacteria).
•Fractionated
•protein-based ( e.g. toxoid )
•polysaccharide-based

26. 1. Live attenuatedVaccines
• Attenuated (weakened) form of the "wild" virus or
bacterium
• Must replicate to be effective
• Immune response similar to natural infection
• Usually produce immunity with one dose, except those
administered orally
• Severe reactions possible
• Interference from circulating antibody
• Fragile – must be stored and handled carefully
• Viral:
• measles, mumps,rubella, varicella/zoster, yellow fever, rotavirus
etc..
• Bacterial BCG, oral typhoid

27. 2. InactivatedVaccines
• Cannot replicate
• Generally not as effective as live vaccines
• Less interference from circulating antibody than live vaccines
• Generally require 3-5 doses
• Immune response mostly humoral
• Antibody titre may diminish with time
• Whole cell vaccine
• Viral polio, hepatitis A, rabies, influenza
• Bacterial: pertussis, typhoid, cholera, plague
• Fractionated
• Subunit hepatitis B, influenza, acellular pertussis,human
papillomavirus, anthrax
• Toxoid: diphtheria, tetanus

28. Pure PolysaccharideVaccines
• Not consistently immunogenic in children younger than 2
years of age
• No booster response
• Antibody with less functional activity
• Immunogenicity improved by conjugation

29. Polysaccharide Vaccines
• Pure polysaccharide
• pneumococcal
• meningococcal
• SalmonellaTyphi (Vi
• Conjugate polysaccharide
•Haemophilus influenzae type b
•pneumococcal
•meningococcal

30. DNA vaccine
• Is a coding DNA sequence used as a vaccine when injected
into cells, it is translated to form antigenic protein of
pathogens. As this protein is foreign to cells , so immune
response raised against this protein.
• Advantages over traditional vaccines:
• Uses only the DNA from infectious organisms.
• Avoid the risk of using actual infectious organism.
• Provide both Humoral & Cell mediated immunity
• Refrigeration is not required
• Expressed inside cell, so no problem with all kinetics
• Disadvantages:
 Limited to protein immunogen only
 Extended immunostimulation leads to chronic inflammation
 Some antigen require processing which sometime does not occur

31. Nucleic Acid (DNA)Vaccination
• Nucleic acid (DNA) vaccination is a technique for
stimulation of the immune response against a disease
causing agent by injecting the genetically engineered
DNA of it to create protection .
• This technique is still under investigation, and it has been
applied to a number of viral, bacterial and parasitic
models of disease, as well as to several tumour models.
• Although DNA vaccines are untested in the clinical
setting, they have a number of potential advantages over
conventional vaccines, including the ability to induce a
wider range of immune response types and no risk for
infection

32. DNA vaccine technology
Viral/bacterial
gene
Expression
plasmid
Plasmid carrying foreign gene Inject into host in different
delivery ways:
Recombinant DNA
Technology

33. Delivery of DNA vaccines
•Syringe delivery
Either intramuscularly or
Intradermally

34. Gene gun delivery:-
 Plasmid DNA into gold particles
 Infected into body with gene gun.

35. Muscle Cells Plasmid DNA
+
What happens after you inject into muscle?
DNA vaccine works by two pathways:
endogenous pathway and exogenous pathway

36. mRNA
Antigenic
Protein
MHC-I
Plasmid
DNA
Nucleus
1. endogenous pathway: antigenic protein stays
inside cell

37. Multiply
Memory T cells
T- Helper Cell

38. 2. Exogenous pathway: immunogenic protein
exported outside cells
Antigenic Protein comes
outside

39. Phagocytosed
Antigen Presenting Cell
Antigenic Peptides
T- Helper Cell
Cytokines
Activated B-Cell Memory B-Cell
Plasma B-Cell
Memory
Antibodies
MHC-II

40. When the virus enters body second time
Viral Protein
Memory T-Cell
Antibodies

41. Current DNA vaccine clinical trials.
Ferraro B et al. Clin Infect
Dis. 2011;53:296-302

42. Toxoids
 Toxoids made by inactivating the toxin that
some infectious agents create.
 Toxoids used against Tetanus and Diphtheria.
Advantages Disadvantages
- You only have to have
the vaccine once or
twice.
- They will never be
reactivated and cause
the disease.
- They have to be
refrigerated.

43. Subunit Vaccines
 Made by taking apart an infectious agent and only
using the antigenic part (the part that stimulates
an immune response).
 Example vaccines: Hepatitis B and Streptococcus
pneumoniae
Advantages Disadvantages
- They cannot cause
the disease.
- They are more difficult to
make and require new,
expensive technology.