Download MBBS (Bachelor of Medicine and Bachelor of Surgery) Latest Vaccine Lecture PPT
ANTIGEN
Any substance when introduced in body stimulate the
production of antibody and react with the specific antibody
and antigen receptor on lymphocytes are called antigen.
IMMUNOGEN ?are molecules which induce an immune
response.
All antigen are immunogen but all immunogen are not antigen.
ANTIGEN
Most natural occurring antigen are protein, polysaccharide
followed by lipid and nucleic acid.
All protein are not antigen in nature.
TYPES OF ANTIGEN
ON THE BASIS OF IMMUNOGENICITY---
complete antigen
Hapten
Based on origin
1. Exogenous antigen-- present outside the cell.
2. Endogenous antigen ? antigen of self immune system.
3. Microbial antigen ? Flagellar H-antigen
4. Tissue antigen -- Blood group antigen, Transplant
antigen.
ADJUVENT
Substance when mixed with an antigen and injected with it , boost
the immunogenicity of antigen.
Eg-Aluminium potassium sulphate.
VACCINE.
Vaccine is any preparation intended to produce
immunity to a disease by stimulating the production
of antibodies .
Administration vaccine by injection, or given by
mouth, nasal spray.
Vaccination benefits---vaccination intend to provide
individuals with immunological protection before an
infection actually takes place.
VACCINE.
Vaccine is a part of immunization.
Immunization is the process of becoming immune.
IMMUNIZATION-
ACTIVE
a. Natural - exposure to infection
b. Artificial- vaccination
PASSIVE
Natural -Natural maternalAb
. Artificial -Ab therapy, serum
VACCINE.
Vaccination for prevention of disease not for cure
Vaccination reduced burden of illness and death
Vaccine is a suspension of organism or fraction of
organism that is used to induce immunity.
Vaccine teaches the immune system by mimicking a
natural infection.
CLASSIFICATION OF VACCINE
1.classical vaccine
2. modern vaccine
Classical vaccine--
Traditional or conventional. eg-small pox vaccine.
Not product from genetic or chemical engineering
technology.
CONCEPT OF EDIBLE VACCINE.
Introduce gene of interest into plant.-----
(Transformation)===Gene expressed in plant tissue
edible part( Transgenic plant).
|
Gene encode protective vaccine antigen from
viral, parasitic....pathogen that causes disease in
human being.
|
Ingestion of edible part of the transgenic plant( oral
delivery of vaccine).
HOW DO VACCINE WORK
The immune system recognise the vaccine as foreign,
an immune response to it. The vaccine serves as an
antigen and causes the immune system to response
to it.
One part of immune system create antibodies and
that is called humoral response.
Antibodies are specific to the vaccine and have the
ability to remember it so vaccine or very similar
antigen is seen again immune system become active
and protect the person from infection.
Conventional vaccine production method.
PATHOGEN,SELECTION OF
STRAIN
CULTURE, GROWING OF
MICROORGANISM
PURIFICATION,INACTIVATION,
VACCINE.
VACCINE PRODUCTION.
VACCINE.
VACCINE PREPARATION METHOD.
VACCINE
TREND IN VACCINE DEVELOPMENT >
>
Modern molecular biology
>Recombinant DNA technology
>and genetic engineering have opened the road for
alternative vaccine production.
GENETIC APPROACH.
CONCEPT OF VACCINATION.
Disease causing microorganism
|
disease
|
Recovery, Death, disability, immune response.
Vaccnination ----- no disease-----immune response
----immunity.
TYPE OF VACCINE
WHOLE ORGANISM VACCINE
killed(pertusis, cholera,rabies)
Live attenuated(BCG,OPV,MMR)-living but weakened microbes.
PURIFIED MACROMOLECULES AS A VACCINE
Toxoid- -Inactivated toxin.
capsular polyssacharide --- (pneumococcal)
Cell wall polyssacharide --- (meningococcal)
Surface antigen ----- (HEP ? B)
COMBINATION.
?NEWER APPROACH
NEWER VACCINE
1.Recombinant vaccine.
2.DNA VACCINE (Nucleic acid vaccine).
According to microorganism
Bacterial .
Viral(OPV, MMR)
Rickettsial (epidemic typhus).
?FUTURE PROSPECT
q Use of recombinant DNA technique to insert the gene
coding for the protein of interest into the genome of
avirrulent virus that can be administered as vaccine.
NUCLEIC ACID---
> is obtained from collected and
lysed cell.
Nucleic acid is purified by chromatography
technique.
Nucleic acid vaccine can be a region of RNA or
DNA that code for disease associated protein.
Recombinant vaccine.
DNA VACCINE A PROMISING FUTURE
DNA VACCINE-------(NUCLEIC ACID VACCINE).
> Are third generation vaccines
and are made up of small , circular piece of
bacterial DNA (Called as plasmid) that has been
genetically engineered to produce one or two
specific protein(antigen) from microorganism. The
vaccine DNA is injected into the cells of body where
the " inner machinery" of the host cell reads the
DNA and convert it into pathogenic protein.
ADVANTAGE OF DNA VACCINE
Cheaper and easier to produce
No need to handle infection during production
Safer
Induce both CMI and humoral.
No cold chain required.
IMMUNIZATION.
Immunization : method by which artificial immunity
TYPE OF VACCINE-
Live attenuated vaccine--containing
live microorganism with reduced virulence.
Prepared by using attenuated strain of
microorganism.
Live vaccine initiate infection without causing disease.
Booster doses are not required.
Single dose is required. Induces cmi and humoral
immunity.
Longer and effective immunity.
KILLED VACCINE.
Containing killed or inactivated microorganism.
Inactivation of agent by heat, phenol.
Induces active immunity but level of immunity
induced is less as compared to live vaccine.
Short duration so booster is required.
Killed vaccine
Safe and stable.
Can be given with polyvalent vaccine.
Multiple injection are needed.
Oral route is not suitable.
Local and CMI can not be induced.
TOXOID.(inactivated toxin).
FEW microorganism Diptheria, tetanus bacilli ,
produce exotoxin which play important role in
causing disease.
Toxin can be detoxified and used for immunisation.
Detoxified toxin is known as toxoid, which is non
toxic but antigenic.
Prepared by toxin with formaline.
TOXOID VACCINE
Toxoid produces antitoxin which react with toxin
and neutralises it.
Eg- Tetanus toxoid, Diptheria toxoid.
Antigenecity of toxoid can be potentiated by an
adjuvent.
Immunizing agent.
1. vaccine
2.immunoglobulins
3. Antisera.
TYPE OF VACCINE
Live attenuated vaccine(harmless)
Killed vaccine
Cellular fraction
Recombinant vaccines
Combined vaccines(MMR,DPT).
CELLULAR FRACTION
Vaccine prepared using extracted cellular fraction.
Meningococcal vaccine from antigen of the cell wall.
Pneumicoccal vaccine from the capsular
polyssacharide.
RECOMBINANT VACCINE
Gene responsible for specific antigen are cloned in
organism.
Technique is known as recombinant technology. Eg-
Hepatitis B vaccine.
COMBINED VACCINE
Vaccine are prepared containing more than one
immunizing agent. Also known as mixed vaccine.
DPT.
DT.
DP.
MMR.
DPTP.
IMMUNOTHERAPY
Immunoglobulins and antisera are used for
immunotherapy.
NORMAL HUMAN IMMUNOGLOBULIN
SPECIFIC HUMAN IMMUNOGLOBULINS
Normal human Immunoglobulins
It is antibody rich fraction derived from blood,
Plasma, or serum or human donor.
Contains high level of antibody specially IgG.
ROLE ----
Used against highly susceptible individuals
and to provide temporary protection. Eg--
Measles, Hepatitis A, immunodeficiency diseases.
SPECIFIC IMMUNOGLOBULINS.
Prepared from serum or plasma of convalescent individuals(
patient who have recently recovered from infection.)or Those who
have have been hyper immunized with specific antigen and are
used for passive immunization.
These preparation contains high level of specific antibody.
Rabies Ig, Hep B Ig, tetanus Ig, Rhd Ig.
ANTISERA and ANTITOXINS.
Applied to materials prepared in animals
Antiserum is prepared by injecting specific antigen that leads
to formation of specific antibody formation eg, Rabies
antiserum.
ANTITOXIN is prepared from injecting toxins or toxoid. Eg ?
anti tetanus toxin, anti snake venum....
anti sera and antitoxins are used for passive immunization
only in clinical situation in which there is no alternative.
Vaccine developement.
Formul,,vacc
Growing
micro,purif..isolat
Selecting strain
Quality cont
for vacc.
Inacti..micro
Lot release
GROWING THE MICROORGANISM
GROWING BACTERIA...
Method....
BATCH CULTURE ----
microbes is grown in closed vessels, test tube or
flask.
Continuous culture----
microbes grown in a closed vessels which has
medium constantly added...
GROWING VIRUS
Methods used are---
CELL CULTURE / TISSUE CULTURE= cultured cells are
grow in sheets that support viral replication ....
BIRD EMBRYOS- Incubating egg is an ideal system.
Virus is injected through cell..
ISOLATION AND PURIFICATION.
Product isolation--is the removal of those component whose
properties vary from that of desired product.
Purification=== selectively separates and retain the desired
product..
CENTRIFUGATION ?process by which solid particle separated
from liquid. Eg-cell, debris, dead cells.
Differential centrifugation--for cell organelles.
FILTERATION ?separation of particle from liquid by applying
pressure to the solution to force solution through a filter.
CHROMATOGRAPHY.
FORMULATION OF VACCINE
Other than microorganism or its part a vaccine contain the
following substance.
Suspending fluids.-liquid which contain the chemical used during
production which kills or weakens the organism for use in
vaccine.
Sterile water, saline,or fluid containing protein.
PRESERVATION AND STABILIZERS
VACCINE REMAINS UNCHANGED-------
Albumin, phenol, Glycine, Antibiotics.
INACTVATING AGENT
Formaldehyde, Glutarldehyde etc.......
ADJUVENT ENHANCE VACCINE
IMMUNOGENICITY.
Aluminium gells.
Used in............ DPT
DT
HPV
ADJUVENT OR ENHANCERS.......
QUALITY CONTROL
STERLITY = No live organism present in product.
CHEMISTRY== For correct amount of preservative, adjuvent.
SAFETY=== Overdose of product not causes harm.
LOT RELEASE=== Prior to release , the manufacturer must test each batch,
serial for purity, safety , and potency. ( purity means testing contaminants ).
This post was last modified on 30 November 2021