what is the definition of subunit vaccines?

Question

I am stuck on this one!!!

Answer 1

its a type of HIV caccine

4 General Types of HIV Vaccines

Live attenuated vaccines

Uses a weakened form of the pathogen
Mimics true infection enabling the body to produce an immune response.
Not currently being developed for human use because of safety concerns- as the mechanism of protection is not yet fully understood there are currently no human trials underway.
Animal studies were shown to produce high levels of protection.


Subunit vaccines
Contain a small protein or piece of the pathogen which acts as a foreign antigen
This foreign antigen will initiate the production of antibodies for B cells.
When the entire pathogen enters the body, the antibodies will attach to the proteins on the outer shell of the pathogen, coating it and ‘neutralize’ it
The first AIDS vaccine to go through complete testing in humans, the AIDSVAX gp120 vaccine, was a subunit vaccine. This vaccine failed to protect against HIV infection in an efficacy trial.


Recombinant vector vaccines
Genes are carried by a harmless or very weakened bacterium or virus vector.
Genes are attached to the DNA of the vector, carrying the genes into the human cell.
Once in the human cell, genes produce protein(s) to which the body produces an immune response.
Recombinant vector vaccines will not cause HIV infection because it contains copies of only one or several HIV genes, not all of them. It is believed that the addition of a vector will allow the vaccine to be more effective in creating an immune response than a DNA vaccine alone.


DNA vaccines

Use copies of single or multiple genes from the pathogen.
Genes enter into human cells and use the cell’s ‘equipment’ to produce some protein(s) of the pathogen encoded by the gene(s)

When the protein is produced, the immune system sees it as a foreign or harmful antigen and produces an immune response
The immune system remembers this response, which will prepare a response against the whole pathogen
DNA vaccines will not cause HIV infection, because the vaccines do not contain all the genes of the live pathogen.

Answer 2

Aren't they just vaccines against viral subunits?