Developing Recombinant DNA Vaccines

Question 1

What are 1st generation vaccines?

Answer 1

Attenuated and inactivated
Vaccine formulation includes the entire pathogenic organism

Question 2

What are limitations on 1st generation vaccines?

Answer 2

Reversal of attenuation and immunocompromised patients getting ill, they only work for pathogens with low antigenetic variability

Question 3

What are 2nd generation vaccines?

Answer 3

Contain specific antigens e.g. reverse vaccinology and recombinant DNA technology

Question 4

What are limitations of 2nd generation vaccines?

Answer 4

Difficult to attain purified antigenic components, some expression systems require specific and costly cell cultures

Question 5

What are 3rd generation vaccines?

Answer 5

Use human host as the antigen expression system
DNA vaccines and vectors

Question 6

Pros of 3rd generation vaccines?

Answer 6

No risk of infection, both humoral and cell-mediated response, induce long-lived immunity and increased cytotoxic T-cell responses and high purification costs avoided

Question 7

Cons of 3rd generation vaccines?

Answer 7

Concerns of anti-DNA antibody production, low efficiency, poor immunogenicity and lack of knowledge of how these vaccines work