DNA Vaccine

Conventional vaccines typically include weakened or inactive versions of viruses or bacteria. These vaccines work by triggering your immune system to recognize and respond to the disease-causing agent, thereby safeguarding you from future exposures. Recently, researchers have pioneered a new approach in vaccine development, leveraging genetic material like RNA or DNA from viruses or bacteria to bolster your body’s defense mechanisms. mRNA vaccines, which utilize messenger RNA, are currently deployed against the COVID-19 virus. Moreover, scientists are exploring the potential of DNA vaccines as an additional strategy in combating not only COVID-19 but also other contagious diseases.

What Is a DNA Vaccine?

DNA, or deoxyribonucleic acid, serves as the genetic blueprint within the cells of all living organisms, dictating how cells replicate themselves in your body. Since the 1990s, scientists have explored the potential of using DNA to formulate vaccines, resulting in what we now call DNA vaccines.

How Does the DNA Vaccine Work?

Upon receiving a DNA vaccine, your cells decode the genetic material from the virus or bacteria into a protein recognized by your body as foreign. Consequently, your immune system generates antibodies that target these specific proteins, preventing them from attaching to your cells and ultimately eliminating them. Essentially, DNA vaccines educate your body to identify these proteins, thus thwarting future infections.

How Does a DNA Vaccine Differ From Traditional Vaccines?

Unlike traditional vaccines, which utilize whole viruses or bacteria, or fragments thereof such as proteins or sugars, both RNA and DNA vaccines harness genetic material from the virus or bacteria. This genetic material provides instructions for your body to produce specific foreign proteins, training your immune system to recognize and combat them.

How Do DNA Vaccines Differ From mRNA Vaccines?

Both types of vaccines operate similarly, but while DNA vaccines deliver protein-making instructions in DNA form, mRNA vaccines convey them in messenger RNA form. Importantly, neither DNA nor mRNA vaccines alter your existing genetic makeup or expose you to the disease they’re targeting.

What Are the Advantages of DNA Vaccine?

It offer several potential advantages over traditional and even mRNA vaccines:

1. Rapid development: Creating large quantities of genetic material is easier than producing proteins or culturing viruses or bacteria, enabling swift vaccine development, crucial during outbreaks of rapidly mutating and spreading pathogens.
2. Ease of transport and storage: DNA is inherently stable, eliminating the need for stringent temperature control during storage, unlike mRNA vaccines.
3. Cost-effectiveness: The production and purification of substantial amounts of DNA from viruses or bacteria are less expensive compared to traditional vaccine manufacturing.

DNA Vaccine and COVID-19

In September 2021, India granted emergency authorization for the world’s first DNA vaccine for human use, ZyCoV-D, developed by Zydus Cadila pharmaceutical company. Approved for emergency use in adults and children aged 12 and above, ZyCoV-D requires three doses, administered 28 days apart, delivered via a device that injects the vaccine into the skin. Clinical trials involving 28,000 volunteers revealed ZyCoV-D to be 67% effective in preventing severe illness from COVID-19.

DNA Vaccines and Challenges

Although DNA vaccine technology shows promise, challenges persist. While researchers explore DNA vaccines’ potential in combatting HIV and certain cancers, as of September 2021, the FDA had only approved DNA vaccines for specific animal diseases. Further research is essential to understand DNA vaccines’ immune response, safety profile, potential side effects, and overall effectiveness against COVID-19 and other infectious diseases caused by viruses or bacteria.

References:

• World Health Organization: “DNA Vaccines,” “The different types of COVID-19 vaccines.”
• Science Media Center of the U.S.: “DNA Vaccines.”
• Harvard College Global Health Review: “DNA Vaccines: Scientific and Ethical Barriers to the Vaccines of the Future.”
• Children’s Hospital of Philadelphia: “How Do DNA Vaccines Work?”
• Elsevier Public Health Emergency Collection: “DNA vaccines against COVID-19: Perspectives and challenges.”
• BBC News: “Zydus Cadila: India approves world’s first DNA Covid vaccine.”
• Life Sciences: “DNA vaccines against COVID-19: Perspectives and challenges.”
• Government of India Department of Biotechnology: “World’s First COVID-19 DNA Vaccine: The Scientific Journey.”