ARS | Publication request: THE BASICS OF DNA VACCINES (NUCLEIC ACID-MEDIATED VACCINES IN VETERINARY MEDICINE, 9/22/98, AMES, IA)

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: September 22, 1998
Publication Date: N/A

Technical Abstract: Nucleic acid mediated or DNA vaccines (NAMV) are a revolutionary new method for inducing an immune response in animals or humans for protective or therapeutic purposes. The use of these vaccines have potentially wide ranging application from vaccination against viral, bacterial, and parasitic diseases to use in cancer therapy. This method of immunization involves the direct introduction of naked DNA into the vaccinate. The DNA is taken up by a limited number of cells of the host where it directs expression of a native, immunogenic protein. This is accomplished by introducing the NAMV into muscle or epidermis of the vaccinate by direct injection or into the epidermis by particle bombardment. The small number of cells taking up the plasmid DNA express the encoded protein. Some of the expressing cells may display portions of the protein on the cell surface with MHC I molecules, leading to a cell-mediated immune response. The protein can also be secreted or released from the expressing cell where it is taken up and processed by antigen processing cells. The antigen is displayed by MHC II molecules, leading to a humoral immune response. This type of vaccination has several advantages over conventional vaccines. First, NAMVs can elicit both humoral and cell-mediated responses as compared to primarily humoral responses of conventional vaccines (exception: attenuated live vaccines), and their use is not affected by pre-existing antibody. NAMVs are noninfectious and cannot be transferred to secondary hosts or change to a more virulent form. The NAMVs are purified DNA, thus can be stored at room temperature, allowing for widespread use.