Making the patient’s body produce the cancer antigens
Traditional vaccination aims at injecting an antigen into a receiver, to trigger an immune response against this antigen and set up immunological memory. The goal of DNA vaccination is instead to inject the antigen’s DNA, making the receiver’s body produce the antigen. Upon receiving the DNA vaccine, Antigen Presenting Cells (APCs) will produce the antigen corresponding to the DNA, and present it to other immune cells like it would in the case of a usual infection.
Typically, the vaccinating DNA is integrated into plasmids, which are circular strands of DNA used by bacteria in addition to their chromosomal genetic material. The plasmids are then injected to the patient intradermally (through the skin), and find their way into the nucleus of various patient’s cells, including APCs. The DNA carried by the plasmid will not fuse with the patient’s chromosomes, but will still be translated into proteins by the cellular machinery. Thus, the APC will start expressing the antigen encoded by the plasmid, and present it to the immune system to trigger a specific response.
DNA vaccination is a technology with many advantages compared to conventional approaches. The antigen is produced by the patient’s cells, allowing for post-translation modifications to occur, and presented by both MHC class I and II to generate cell-mediated and humoral immune responses. DNA vaccination allows a polarization of the T helper response towards Th1 or Th2. Additionally, there is no need for the costly laboratory production and purification of recombinant proteins, making DNA-based products easy to produce, stable over time and cost effective.
In oncology, the purpose of DNA vaccines is to induce the production of cancer-specific antigens in the patient’s body. Specialized Antigen Presenting Cells (APCs) will then activate the appropriate immune responses. This allows the patient’s immune system to target and destroy cancer cells. Invectys’ IVS-2001, uses this technology to induce an immune response to telomerase peptides.
The vaccine is administered via needle-free injection for minimal patient discomfort.
A glossary is available for technical definitions.
