Shingles is a painful rash caused by the varicella-zoster virus (VZV), the same virus responsible for chickenpox. After a chickenpox infection, the virus remains dormant within the body’s nerve cells and can reactivate later in life, particularly in individuals over 50. This reactivation leads to the characteristic blistering rash and nerve pain associated with shingles. Vaccination is a crucial preventative measure against this condition and its potential long-term complications. Many people wonder if the current shingles vaccine utilizes messenger RNA (mRNA) technology, similar to some recent vaccines.
The Shingles Vaccine Technology
The current shingles vaccine, known as Shingrix, does not use mRNA technology. Instead, it is classified as a recombinant subunit vaccine. Recombinant subunit vaccines contain only specific, purified parts of a pathogen, rather than the entire weakened or inactive virus. This approach aims to trigger an immune response without exposing the recipient to the entire infectious agent.
Shingrix specifically uses a protein found on the surface of the varicella-zoster virus called glycoprotein E (gE). This gE protein is produced through recombinant DNA technology, where its genetic instructions are inserted into another organism, often for mass production. The vaccine also incorporates an adjuvant system, AS01B, designed to enhance the immune system’s response to the gE protein.
How the Vaccine Works
When Shingrix is administered, it introduces the purified glycoprotein E to the body’s immune system. Immune cells recognize this gE protein as a foreign substance, even though it cannot cause the disease itself. This recognition prompts the immune system to mount a targeted defense. The body begins to produce specific antibodies and specialized T-cells that can identify and neutralize the varicella-zoster virus.
This process trains the immune system to respond rapidly and effectively if the actual VZV reactivates in the future. The pre-existing antibodies and T-cells are then prepared to fight off the virus, preventing the development of shingles or significantly reducing its severity. The adjuvant component within the vaccine amplifies and prolongs this immune response, which leads to stronger and more durable protection.
Understanding Different Vaccine Technologies
In contrast to recombinant subunit vaccines like Shingrix, mRNA vaccines operate differently by delivering genetic instructions, in the form of messenger RNA, to the body’s cells. These instructions guide the cells to temporarily produce a specific viral protein themselves. The immune system then identifies this newly produced protein as foreign and builds a protective response against it.
While both technologies aim to train the immune system, subunit vaccines deliver the protein directly. In contrast, mRNA vaccines provide the blueprint for the body to create the protein internally.