Vaccines

A product that produces immunity therefore protecting the body from the disease

smallpox

rinderpest, "cattle plague"

H1N1 (swine) influenza virus vaccine

the health and welfare of the individual animal are primary concerns

improving overall production and the cost-benefit resulting from vaccination

- reducing or eliminating the risk for the consumer (human)

- in some cases improving the productivity of the animal

- reducing the risk of human infection in contact with wildlife

- welfare concerns of wildlife are of increasing importance

- Human has higher potential returns, investment in R&D, medium to high complexity, highly stringent regulatory and preclinical requirement, longer time to market launch

-veterinary has lower potential returns, less investment in R&D, high complexity, less stringent regulatory and preclinical requirement, shorter time to market launge and can research any time on target species

- preventive vaccines (traditional vaccine)

- therapeutic vaccines

- other types of vaccines

- most vaccines fall into this category

- preventing diseases or symptoms

- most are against infectious diseases

- relatively new type of vaccines

- used for treating patients with diseased conditions, such as cancer, allergy and infectious diseases

- for production

- for fertilization control

produces antibody by B-cells

cytotoxic T cells (kill infective cell)

• - must be safe
• - produce protective immunity
• - cost-effective
• - long-lasting
• - easy to be distributed
• - easy to be administrated

• - live attenuated vaccines
• - killed vaccines
• - subunit vaccines
• - recombinant vaccines
• - genetic (DNA) vaccine
• - vectored vaccines

• - synthetic peptide or epitope vaccines
• - edible vaccines

• - capable of replicating
• - do not cause disease
• - induce strong immune responses (T and B cells)
• - long duration (single dose)

• - reversion to wild type
• - cause disease in immunodefficient individuals
• - potential recombination with wt pathogens
• - hypersensitivity reaction

• - serial passages in vitro or in vivo (traditional way)
• - host range mutants
• - isolation of naturally attenuated pathogens
• - isolation of conditional or TM sensitive mutants
• - genetic modification (main method now)

• - not capable of replicating
• - do not cause disease
• - induce relatively weak immune responses, esp. T cell response
• - shorter duration (multiple doses)
• - adjuvant is added

• - vaccine not completely killed
• - contamination
• - hypersensitivity

• - heat inactivate the pathogens
• - chemical treatments, such as formaldehyde

Objective: to inactivate the pathogens but maintain antigenecity

add to vaccine to enhance immune response

• - components of pathogen included
• - do not cause disease
• - induce weak immune responses
• - shorter duration (multiple doses)
• - conjugated or adjuvanted to achieve efficacy

to make more antigenic (protein)

- hypersensitivity

(1) Grow the pathogen --> (2) inactivate and lyse the pathogen --> (3) isolate and purify the components --> (4)conjugated with carriers and adjuvanted--> (5) subunit vaccines

• - single component of pathogen included
• - do not cause disease
• - using recombinant technologies
• - induce weak immune responses
• - shorter duration (multiple doses)
• - adjuvanted to achieve efficacy

BEST SAFETY PROFILE

(1) cloning of the antigen --> (2) expression of the antigen --> (3) isolation and purification of the antigen --> (4) formulation --> (5) recombinat vaccine

• - easy to be produced
• - cost-effective
• - induces humoral and cellular immunity
• - combination of multiple antigens
• - low delivery efficiency/efficacy?

- potential integration

(1) virus --> (2) gene--> (3) plasmid --> (4) vaccination

(attenuated or non-pathogenic viruses or bacteria as vaccine carriers)

• - capable of replicating
• - do not cause disease
• - induce stronger immune responses
• - longer duration

• - reversion
• - recombination

• - combination of multiple peptides
• - cost-effective
• - good safety profile
• - efficacy

small regions (fragments of proteins) where antibody binds

• - easy to be produced
• - no injection, no needle
• - easy to be stored
• - no training for administration
• - even taste good
• - cost-effective
• - good safety profile
• - efficacy?

- differentiating infected from vaccinated animals

• - especially for disease-free countries
• - eradication program

• - cancer: anticancer vaccines against canine malignant melanoma
• - immunocontraception vaccines (anti-GnRH vaccine
• - immunoneutering vaccines: vaccines against gamete antigens (wildlife control)
• -vaccines to increase fertility: anti-androstenedione vaccine (sheep)

• (1) androstenedione
• (2) estrogen
• (3) negative feedback effect on FSH/LH
• (4) decreased fertility