IMMUNOLOGY

Detailed explanation-1: -DNA vaccines work by injecting genetically engineered plasmid containing the DNA sequence encoding the antigen(s) against which an immune response is sought, so the cells directly produce the antigen, thus causing a protective immunological response.

Detailed explanation-2: -The first such vaccines licensed for marketing are likely to use plasmid DNA derived from bacterial cells. In future, others may use RNA or may use complexes of nucleic acid molecules and other entities. These guidelines address the production and control of vaccines based on plasmid DNA intended for use in humans.

Detailed explanation-3: -It protects against extracellular bacteria and foreign macromolecules. The cell mediated immune response depends on antigen-specific T cells and on various non specific cells of the immune system. It protects against intracellular bacteria. DNA vaccines raise both humoral and cellular immunity.

Detailed explanation-4: -However, several DNA-based vaccines have been approved by both the United States Food and Drug Administration (FDA) and the United States Department of Agriculture (USDA) for veterinary use, of which include a vaccine against West Nile Virus in horses as well as a melanoma vaccine for dogs.