Dr. Pulipati Sowjanya
Professor & Head
Dept. of Pharmaceutical Biotechnology
Vignan Pharmacy College
Vadlamudi, Guntur (Dt)
1
INTRODUCTION
2
Vaccines are medical marvels. Basically, they
are purified preparations that can stimulate
body's immune system to produce antibodies
that can provide future, long-term protection
from any exposure to a specific type of
microbe.
A vaccine is a biological preparation that
improves immunity to particular disease.
Edward Jenner
INTRODUCTION (Cont..)
3
A vaccine typically contains an agent that resembles a
disease-causing microorganism and is often made from weakened
or killed forms of the microbe, its toxins or one of its surface
proteins.
This agent stimulates the body's immune system to
recognize the foreign agent, destroy it, and "remember" it, so that
the immune system can more easily recognize and destroy any of
these microorganisms that it later encounters.
1. BACTERIAL KILLED:
a) Cholera d) Typhoid-paratyphoid A&B
b) Pertusis (TAB)
c) Plague e) Typhoid-paratyphoid A,B&C
(TABC)
2.BACTERIALATTENUATED (LIVE):
a) Bacillus calmette guerin (BCG)
3.RICKETTSIAL KILLED: a) Typhus
4.VIRAL KILLED:
a) Influenza c) Poliomyelitis
b) Measles d) Rabies
5.VIRAL ATTENUATED:
a) Measles c) Yellow fever
b) Smallpox d) Poliomyelitis
CLASSIFICATION OF OFFICIAL VACCINES
4
5
Antigen-containing
preparations (Vaccines)
Antibody-containing
preparations (Sera)
Stimulate active immunity Give passive immunity
Patient produces antibodies Patient receives antibodies
Immunity develops slowly Immunity produced quickly
Long lasting effect Temporary effect
Used for long-term prophylaxis
Used for short-term prophylaxis
and therapeutically
Difference Between Vaccines & Sera
TYPES OF VACCINES
❑ These are different forms of vaccines
❑Simple vaccines Eg: Plague (Pasteurella pestis)
➢ Mixed vaccines
➢ Univalent vaccine
➢ Polyvalent vaccines
❑Vaccines are administered by the parental route except
poliomyelitis vaccine which is administered by the oral route.
6
DIPHTHERIA
7
Causative organism:
➢ “Corynebacterium diphtheriae”
Selection of Animal:
➢ Horse
➢ Goat
➢ Injecting the inoculums and
collection of more blood is possible
with horse.
IMMUNE SERA
Diphtheria (cont….)
8
The neck muscles of horse are injected with
toxoid for a few minutes to several months.
The first dose is not more than 5ml and
increased to 600ml to get satisfactory antitoxin
titre
8 litres of blood was withdrawn from
jugular veins into the bottles containing anti
coagulant solution.
Repeat the bleeding twice for the next 8
days after that give rest for 10 days.
PREPARATION
9
Give a short course of antigen to
stimulate further antibody
Repeat 3 bleedings, give rest, course of
antigen and continue bleedings till animal
stops producing a satisfactory antitoxin
titer (usually 4 to 5 courses)
Store the collected blood in refrigerator
till cells are settled
Plasma is siphoned off & calcium
chloride is added to induce clotting
Clot is separated from the serum by
filtration
Serum + ammonium sulphate
Gamma globulin fraction pptd & is separated and discarded
Add ammonium sulphate
Beta globulin fraction + antitoxin is precipitated
Liquid portion with albumin is separated by filter press
Precipitate is transferred from filter cloth to cellulose film
bags
Suspend in tanks of chlorinated running water for dialysis
Ammonium sulphate passes out, remove it and antitoxin passes
back into the solution. Adjust isotonicity
1. Concentration by Fractional Precipitation
10
2. Concentration by Proteolytic Digestion
Diluted serum+pepsin, adjust pH to 4 and incubate at 37°C for 2 days
The albumin is completely digested and pdt will pass through a dialysing
membrane
The gamma-globulin fraction is partly digested to dialysable compounds
and precipitated by PH
The beta-globulin is split into two fragments one of which has antitoxic
activity
The liquid is filtered to remove the pptd gamma-globulin
To the filtrate add ammonium sulphate and heat at 55°C for 1 hr
The inactive fragment of β-globulin is denatured and pptd. It is filtered off
and add more ammonium sulphate to ppt active fragment
This is separated, dialysed, adjusted to isotonicity and preserved
Sunday, October 18, 2020 Department of Biotechnology, Vignan Pharmacy College, Vadlamudi 1411
• The toxoids used as
vaccines are toxins
that are incubated with
formalin
• This completely destroys the toxic properties without loss of
antigenic properties
• Formalin does this by acting directly on the toxic groups
(probably free amino groups) without affecting the
antigenically active sites
TOXOIDS
12
Preparation of toxoid
1. Suitable strain on liquid medium (not made with broth from
horse muscle)
2. Incubate till toxin production reached satisfactory level.
3. Bulk of organisms are removed on paper pulp (to prevent
clogging of bacterial proof filters)
4. Filtrate is sterilized using fibrous pads or ceramic candles.
Conversion to toxoid
1. Add Formaldehyde and incubate at 37°C(2-3weeks) [toxicity
is removed]
2.This is unpurified form (called as Anatoxin) & Purified one are
called Purified formal toxoid.(PFT)
13
TETANUS TOXOID
CAUSATIVE ORGANISM:
➢ “Clostridium tetani”
➢ Anaerobic organism that contains
exotoxin.
14
Toxin is converted to toxoid by adding
formalin and incubate at 37 ̊ C for 2-3
weeks is known as formal toxoid.
To formal toxoid add charcoal to remove
impurities.
Filter the solution and treat the filtrate with alum.
This reacts with bicarbonates, phosphates and
protein impurities in the toxoid to produce a ppt
containing aluminium hydroxide and phosphate.
The toxoid is adsorbed on to the mineral carrier.
The precipitate is washed and suspended in saline
containing bactericide.
15
PURIFIED TOXOID ALUMINIUM PHOSPHATE
The precipitate is separated by filtration and suspended in saline solution.
The toxoid precipitates as aluminium phosphate toxoid.
Add aluminium sulphate and cadmium chloride as protein precipitants
Toxoid is treated with magnesium hydroxide to precipitate colour,
phosphates and proteins.
16
It is a killed bacterial vaccine
CAUSATIVE ORGANISM:
➢ Vibrio cholerae
Conversion into vaccines
➢ Treat the organism with chemical
bactericide like
▪ Formalin
▪ Phenol
▪ Thiomersal
17
CHOLERA ( Cont…)
18
The suspension of vibrio
cholera organism is killed
by either heating or treating
with bactericide.
0.5% formalin and 7%
alcohol are used as
bactericides to develop the
killed strain .
The organism is suspended
in a medium containing the
preservative and freeze dry
the product.
BCG (Bacillus Calmette Guerin)
It is a live attenuated vaccine
Causative organism:
➢ Mycobacterium tuberculae
Preparation:
➢ It is a suspension of live micro organism.
➢ The organism is attenuated to inhibit the pathogenicity and
retains the antigenicity.
➢ The culture grown for not more that 14 days.
19
Bacillus Calmette Guerin (Cont....)
The organism is grown in an appropriate
medium (LJ).
It should be retain the antigenicity as long
as possible .
Freeze dry the product.
When the organism grown in the medium
it forms clumps.
This can be avoided by addition of
polyoxyethylene ether into the medium.
20
21
Virulent rickettsiae are injected into the yolk
sacs of embryonated eggs and incubate for
7days.
These are collected under aseptic conditions
and suspended in saline
Add Formaldehyde solution so that to get a
concentration of about 0.2 to 0.5%.
It is purified with ether or trichloro trifluoro
ethane.
PREPARATION:
CAUSATIVE ORGANISM: Rickettsia prowazeki
21
22
Cultivation of viruses in vaccine production
Since viruses are intracellular parasites they will
grow only within living cells.
1. Free – Living Animals
2. Fertile Eggs
3. Tissue Culture
23
Free-Living Animals
Very few vaccines are made using free-living animals.
The products are good antigens but the method is
inconvenient and costly.
❖Typhus - Lungs of rodents
❖Rabies – Brains of sheep or rabbits
❖Poliomyelitis – Kidneys of monkeys
24
Fertile Eggs
Advantage:
Easier to keep the product free from contamination
Precautions:
1. Strict asceptic conditions
2. Repeated passage of virus from egg to egg must be avoided.
3. Viruses grown in the yolk sac or embryo are separated by
grinding to prevent traces get protein get into the vaccine.
4. The eggs must be candled to confirm the embryos are alive.
25
26
1. SELECTION OF SUITABLE TISSUE
Viruses grow only in primate cells- monkey kidney has
become the most widely used. (Eg: in poliomyelitis, measles)
• Attenuated measles: chick embryo.
• Cow pox: calf embryo skin.
• Tissues should be free from living microbes.
1.Maintainence of cleanliness of cells by continuous subculture.
2.Establishment of growth and maintenance of metabolism under
artificial conditions.
3.Organ or tissue removed is cut up or minced and treated usually
with trypsin, to disperse the cells.
TISSUE CULTURE
27
TWO TYPES OF CULTURE
(A) suspended cell culture
❖ Suspended in liquid medium & maintains cell metabolism &
very little or no proliferation.
(B) Fixed cell (monolayer) culture
❖Few cells are maintained in medium to settle on one side of large
flat sided bottle.
❖On incubation they attach to glass & multiply into uniform layer
one cell thick and spread over the lower side of bottle.
❖Higher yield of virus per cell, as multiplication occurs. Easier to
change medium
28
1. Balanced salt solution –Optimum PH & osmotic pressure
2. Nutrients: aminoacids, growth factors, dextrose, protein
hydrolysates etc. Serum & proteins must be excluded
3. A PH Indicator phenol red to show the state of cell
metabolism.
4. Antibiotics, both antibacterial and antifungal to prevent growth
of the contaminants.
5. Heavy metals are toxic to culture so in low concentration.
2.MEDIA NEEDED TO MAINTAIN THESE CULTURES
29
• After the suspended cells have become adjusted to medium or
monolayer has fully developed seed virus is added and incubated.
• Here it is rocked to prevent accumulation of high concentration of
harmful metabolites on the surface of tissue cells & to ensure free
exchange of oxygen and CO2.
• Virus invades cells, multiplies and is released into medium at the
end of incubation.
• After suspended cells are allowed to settle, is siphoned off
aseptically.
3. CULTIVATION OF VIRUSES IN THE CELLS
30
POLIOMYELITIS
❑ There are 3 distinct antigenic types of poliomyelitis virus
Type-I, Type-II, Type-III.
❑ The 3 types of virus are grown separately in cell culture of monkey
kidney tissue.
❑ Rhesus monkeys are used. They are quarantined and checked for
communicable disease.
31
Inactivated Vaccine: It is known as Salk-type after the American
virologist who first developed it.
After the virus suspension has been harvested it is tested for
1. The correct strain of poliomyelitis virus
2. The virus titre
3. Free from viral, bacterial and fungal contaminants.
➢ The viral suspension is passed through filters to remove tissue cells
and bacteria.
➢ Inactivated by treating with 0.01% formaldehyde under controlled PH
and temp with magnetic stirrer.
➢ This process takes around 6 days.
➢ Neutralize the formaldehyde with sodium metabisulphite & add
thiomersal as bactericide.
32
POLIOMYELITIS
Attenuated (Oral) Vaccine: It is known as Sabin-type after the American
virologist who first developed it.
It is manufactured in same way as Salk-type except that-
➢Attenuated strains, prepared by rapid passages through tissue cultures
of monkey kidney cells, are used.
➢There is no inactivation stage
➢In addition to testing for freedom from extraneous bacteria, moulds and
viruses, special tests are necessary, because the virus in the
vaccine is living, to confirm the absence of virulent poliomyelitis virus.
33
POLIOMYELITIS
SMALL POX
CAUSATIVE ORGANISM:
➢ Variola virus
PREPARATION:
Living cow pox virus are used.
Vaccine is usually obtained from lesions produced on the skin of living
mammals Eg: healthy calves and sheep.
Inoculation
The flanks and abdomen are scrubbed, disinfected shaved rescrubbed and
redisinfected.Then in special rooms, the shaved areas are-
(a) scarified, i.e lightly scratched with comb like device, without
drawing blood.
(b) inoculated by rubbing into scratches.
34Department of Biotechnology, Vignan Pharmacy College, Vadlamudi
SMALL POX (CONT.….)
35
Incubation:
During next 4-5 days vesicles development
along the lines of scarification.
Through out this period inoculated areas are kept aseptically
clean.
Harvesting:
• Animals are killed, exanguinated and washed.
• Contents of vesicles are (lymph) removed by curretage i.e
by scraping with Volkmann's spoon
• Pooled material is homogenized.
• Postmortem the animal to confirm absence of diseases.
SMALL POX (CONT.….)
Purification:
1.Done by grinding with equal volume of glycerin & storing
at -10ºC for long time.
2.Lymph extracted with protein solvent
Eg: trichlorofluoroethane
3. Phenol 0.4% & incubated at 22ºC
4. Glycerin 40% & peptone 1% at -10ºC.
5. Brilliant green to mark the area of application of vaccine.
36
37

Vaccines & Sera

  • 1.
    Dr. Pulipati Sowjanya Professor& Head Dept. of Pharmaceutical Biotechnology Vignan Pharmacy College Vadlamudi, Guntur (Dt) 1
  • 2.
    INTRODUCTION 2 Vaccines are medicalmarvels. Basically, they are purified preparations that can stimulate body's immune system to produce antibodies that can provide future, long-term protection from any exposure to a specific type of microbe. A vaccine is a biological preparation that improves immunity to particular disease. Edward Jenner
  • 3.
    INTRODUCTION (Cont..) 3 A vaccinetypically contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins or one of its surface proteins. This agent stimulates the body's immune system to recognize the foreign agent, destroy it, and "remember" it, so that the immune system can more easily recognize and destroy any of these microorganisms that it later encounters.
  • 4.
    1. BACTERIAL KILLED: a)Cholera d) Typhoid-paratyphoid A&B b) Pertusis (TAB) c) Plague e) Typhoid-paratyphoid A,B&C (TABC) 2.BACTERIALATTENUATED (LIVE): a) Bacillus calmette guerin (BCG) 3.RICKETTSIAL KILLED: a) Typhus 4.VIRAL KILLED: a) Influenza c) Poliomyelitis b) Measles d) Rabies 5.VIRAL ATTENUATED: a) Measles c) Yellow fever b) Smallpox d) Poliomyelitis CLASSIFICATION OF OFFICIAL VACCINES 4
  • 5.
    5 Antigen-containing preparations (Vaccines) Antibody-containing preparations (Sera) Stimulateactive immunity Give passive immunity Patient produces antibodies Patient receives antibodies Immunity develops slowly Immunity produced quickly Long lasting effect Temporary effect Used for long-term prophylaxis Used for short-term prophylaxis and therapeutically Difference Between Vaccines & Sera
  • 6.
    TYPES OF VACCINES ❑These are different forms of vaccines ❑Simple vaccines Eg: Plague (Pasteurella pestis) ➢ Mixed vaccines ➢ Univalent vaccine ➢ Polyvalent vaccines ❑Vaccines are administered by the parental route except poliomyelitis vaccine which is administered by the oral route. 6
  • 7.
    DIPHTHERIA 7 Causative organism: ➢ “Corynebacteriumdiphtheriae” Selection of Animal: ➢ Horse ➢ Goat ➢ Injecting the inoculums and collection of more blood is possible with horse. IMMUNE SERA
  • 8.
    Diphtheria (cont….) 8 The neckmuscles of horse are injected with toxoid for a few minutes to several months. The first dose is not more than 5ml and increased to 600ml to get satisfactory antitoxin titre 8 litres of blood was withdrawn from jugular veins into the bottles containing anti coagulant solution. Repeat the bleeding twice for the next 8 days after that give rest for 10 days. PREPARATION
  • 9.
    9 Give a shortcourse of antigen to stimulate further antibody Repeat 3 bleedings, give rest, course of antigen and continue bleedings till animal stops producing a satisfactory antitoxin titer (usually 4 to 5 courses) Store the collected blood in refrigerator till cells are settled Plasma is siphoned off & calcium chloride is added to induce clotting Clot is separated from the serum by filtration
  • 10.
    Serum + ammoniumsulphate Gamma globulin fraction pptd & is separated and discarded Add ammonium sulphate Beta globulin fraction + antitoxin is precipitated Liquid portion with albumin is separated by filter press Precipitate is transferred from filter cloth to cellulose film bags Suspend in tanks of chlorinated running water for dialysis Ammonium sulphate passes out, remove it and antitoxin passes back into the solution. Adjust isotonicity 1. Concentration by Fractional Precipitation 10
  • 11.
    2. Concentration byProteolytic Digestion Diluted serum+pepsin, adjust pH to 4 and incubate at 37°C for 2 days The albumin is completely digested and pdt will pass through a dialysing membrane The gamma-globulin fraction is partly digested to dialysable compounds and precipitated by PH The beta-globulin is split into two fragments one of which has antitoxic activity The liquid is filtered to remove the pptd gamma-globulin To the filtrate add ammonium sulphate and heat at 55°C for 1 hr The inactive fragment of β-globulin is denatured and pptd. It is filtered off and add more ammonium sulphate to ppt active fragment This is separated, dialysed, adjusted to isotonicity and preserved Sunday, October 18, 2020 Department of Biotechnology, Vignan Pharmacy College, Vadlamudi 1411
  • 12.
    • The toxoidsused as vaccines are toxins that are incubated with formalin • This completely destroys the toxic properties without loss of antigenic properties • Formalin does this by acting directly on the toxic groups (probably free amino groups) without affecting the antigenically active sites TOXOIDS 12
  • 13.
    Preparation of toxoid 1.Suitable strain on liquid medium (not made with broth from horse muscle) 2. Incubate till toxin production reached satisfactory level. 3. Bulk of organisms are removed on paper pulp (to prevent clogging of bacterial proof filters) 4. Filtrate is sterilized using fibrous pads or ceramic candles. Conversion to toxoid 1. Add Formaldehyde and incubate at 37°C(2-3weeks) [toxicity is removed] 2.This is unpurified form (called as Anatoxin) & Purified one are called Purified formal toxoid.(PFT) 13
  • 14.
    TETANUS TOXOID CAUSATIVE ORGANISM: ➢“Clostridium tetani” ➢ Anaerobic organism that contains exotoxin. 14
  • 15.
    Toxin is convertedto toxoid by adding formalin and incubate at 37 ̊ C for 2-3 weeks is known as formal toxoid. To formal toxoid add charcoal to remove impurities. Filter the solution and treat the filtrate with alum. This reacts with bicarbonates, phosphates and protein impurities in the toxoid to produce a ppt containing aluminium hydroxide and phosphate. The toxoid is adsorbed on to the mineral carrier. The precipitate is washed and suspended in saline containing bactericide. 15
  • 16.
    PURIFIED TOXOID ALUMINIUMPHOSPHATE The precipitate is separated by filtration and suspended in saline solution. The toxoid precipitates as aluminium phosphate toxoid. Add aluminium sulphate and cadmium chloride as protein precipitants Toxoid is treated with magnesium hydroxide to precipitate colour, phosphates and proteins. 16
  • 17.
    It is akilled bacterial vaccine CAUSATIVE ORGANISM: ➢ Vibrio cholerae Conversion into vaccines ➢ Treat the organism with chemical bactericide like ▪ Formalin ▪ Phenol ▪ Thiomersal 17
  • 18.
    CHOLERA ( Cont…) 18 Thesuspension of vibrio cholera organism is killed by either heating or treating with bactericide. 0.5% formalin and 7% alcohol are used as bactericides to develop the killed strain . The organism is suspended in a medium containing the preservative and freeze dry the product.
  • 19.
    BCG (Bacillus CalmetteGuerin) It is a live attenuated vaccine Causative organism: ➢ Mycobacterium tuberculae Preparation: ➢ It is a suspension of live micro organism. ➢ The organism is attenuated to inhibit the pathogenicity and retains the antigenicity. ➢ The culture grown for not more that 14 days. 19
  • 20.
    Bacillus Calmette Guerin(Cont....) The organism is grown in an appropriate medium (LJ). It should be retain the antigenicity as long as possible . Freeze dry the product. When the organism grown in the medium it forms clumps. This can be avoided by addition of polyoxyethylene ether into the medium. 20
  • 21.
    21 Virulent rickettsiae areinjected into the yolk sacs of embryonated eggs and incubate for 7days. These are collected under aseptic conditions and suspended in saline Add Formaldehyde solution so that to get a concentration of about 0.2 to 0.5%. It is purified with ether or trichloro trifluoro ethane. PREPARATION: CAUSATIVE ORGANISM: Rickettsia prowazeki 21
  • 22.
  • 23.
    Cultivation of virusesin vaccine production Since viruses are intracellular parasites they will grow only within living cells. 1. Free – Living Animals 2. Fertile Eggs 3. Tissue Culture 23
  • 24.
    Free-Living Animals Very fewvaccines are made using free-living animals. The products are good antigens but the method is inconvenient and costly. ❖Typhus - Lungs of rodents ❖Rabies – Brains of sheep or rabbits ❖Poliomyelitis – Kidneys of monkeys 24
  • 25.
    Fertile Eggs Advantage: Easier tokeep the product free from contamination Precautions: 1. Strict asceptic conditions 2. Repeated passage of virus from egg to egg must be avoided. 3. Viruses grown in the yolk sac or embryo are separated by grinding to prevent traces get protein get into the vaccine. 4. The eggs must be candled to confirm the embryos are alive. 25
  • 26.
  • 27.
    1. SELECTION OFSUITABLE TISSUE Viruses grow only in primate cells- monkey kidney has become the most widely used. (Eg: in poliomyelitis, measles) • Attenuated measles: chick embryo. • Cow pox: calf embryo skin. • Tissues should be free from living microbes. 1.Maintainence of cleanliness of cells by continuous subculture. 2.Establishment of growth and maintenance of metabolism under artificial conditions. 3.Organ or tissue removed is cut up or minced and treated usually with trypsin, to disperse the cells. TISSUE CULTURE 27
  • 28.
    TWO TYPES OFCULTURE (A) suspended cell culture ❖ Suspended in liquid medium & maintains cell metabolism & very little or no proliferation. (B) Fixed cell (monolayer) culture ❖Few cells are maintained in medium to settle on one side of large flat sided bottle. ❖On incubation they attach to glass & multiply into uniform layer one cell thick and spread over the lower side of bottle. ❖Higher yield of virus per cell, as multiplication occurs. Easier to change medium 28
  • 29.
    1. Balanced saltsolution –Optimum PH & osmotic pressure 2. Nutrients: aminoacids, growth factors, dextrose, protein hydrolysates etc. Serum & proteins must be excluded 3. A PH Indicator phenol red to show the state of cell metabolism. 4. Antibiotics, both antibacterial and antifungal to prevent growth of the contaminants. 5. Heavy metals are toxic to culture so in low concentration. 2.MEDIA NEEDED TO MAINTAIN THESE CULTURES 29
  • 30.
    • After thesuspended cells have become adjusted to medium or monolayer has fully developed seed virus is added and incubated. • Here it is rocked to prevent accumulation of high concentration of harmful metabolites on the surface of tissue cells & to ensure free exchange of oxygen and CO2. • Virus invades cells, multiplies and is released into medium at the end of incubation. • After suspended cells are allowed to settle, is siphoned off aseptically. 3. CULTIVATION OF VIRUSES IN THE CELLS 30
  • 31.
    POLIOMYELITIS ❑ There are3 distinct antigenic types of poliomyelitis virus Type-I, Type-II, Type-III. ❑ The 3 types of virus are grown separately in cell culture of monkey kidney tissue. ❑ Rhesus monkeys are used. They are quarantined and checked for communicable disease. 31
  • 32.
    Inactivated Vaccine: Itis known as Salk-type after the American virologist who first developed it. After the virus suspension has been harvested it is tested for 1. The correct strain of poliomyelitis virus 2. The virus titre 3. Free from viral, bacterial and fungal contaminants. ➢ The viral suspension is passed through filters to remove tissue cells and bacteria. ➢ Inactivated by treating with 0.01% formaldehyde under controlled PH and temp with magnetic stirrer. ➢ This process takes around 6 days. ➢ Neutralize the formaldehyde with sodium metabisulphite & add thiomersal as bactericide. 32 POLIOMYELITIS
  • 33.
    Attenuated (Oral) Vaccine:It is known as Sabin-type after the American virologist who first developed it. It is manufactured in same way as Salk-type except that- ➢Attenuated strains, prepared by rapid passages through tissue cultures of monkey kidney cells, are used. ➢There is no inactivation stage ➢In addition to testing for freedom from extraneous bacteria, moulds and viruses, special tests are necessary, because the virus in the vaccine is living, to confirm the absence of virulent poliomyelitis virus. 33 POLIOMYELITIS
  • 34.
    SMALL POX CAUSATIVE ORGANISM: ➢Variola virus PREPARATION: Living cow pox virus are used. Vaccine is usually obtained from lesions produced on the skin of living mammals Eg: healthy calves and sheep. Inoculation The flanks and abdomen are scrubbed, disinfected shaved rescrubbed and redisinfected.Then in special rooms, the shaved areas are- (a) scarified, i.e lightly scratched with comb like device, without drawing blood. (b) inoculated by rubbing into scratches. 34Department of Biotechnology, Vignan Pharmacy College, Vadlamudi
  • 35.
    SMALL POX (CONT.….) 35 Incubation: Duringnext 4-5 days vesicles development along the lines of scarification. Through out this period inoculated areas are kept aseptically clean. Harvesting: • Animals are killed, exanguinated and washed. • Contents of vesicles are (lymph) removed by curretage i.e by scraping with Volkmann's spoon • Pooled material is homogenized. • Postmortem the animal to confirm absence of diseases.
  • 36.
    SMALL POX (CONT.….) Purification: 1.Doneby grinding with equal volume of glycerin & storing at -10ºC for long time. 2.Lymph extracted with protein solvent Eg: trichlorofluoroethane 3. Phenol 0.4% & incubated at 22ºC 4. Glycerin 40% & peptone 1% at -10ºC. 5. Brilliant green to mark the area of application of vaccine. 36
  • 37.