Correct option is C
Explanation-
The currently approved and widely used HPV vaccines (e.g., Gardasil, Cervarix) are subunit vaccines that are based on the L1 major capsid protein of the human papillomavirus. These L1 proteins self-assemble into virus-like particles (VLPs), which mimic the outer shell of the virus but lack viral DNA, making them non-infectious and non-oncogenic.
1. These VLPs trigger a strong immune response, producing neutralizing antibodies that prevent HPV infection.
2. This technology is highly effective and safe, and it's the basis for the successful anti-cancer HPV vaccines used to prevent cervical and other HPV-associated cancers.
Incorrect options -
Option A - Chemically inactivated virus – Chemical inactivation is used in other vaccines (e.g., inactivated polio vaccine (IPV)), but not for HPV. Growing HPV in cell culture is technically difficult, as it does not replicate well in standard lab systems.
There's also a safety concern with using even inactivated whole viruses when dealing with a virus linked to cancer.
Option B - Live attenuated mutant form of HPV – HPV vaccines do not use live viruses due to cancer risk. HPV is a DNA virus associated with cancer, and even a weakened form could potentially integrate into the host genome or lead to oncogenic transformation. Live attenuated vaccines are used for diseases like measles, mumps, rubella, etc.
Option D - mRNA vaccine expressing viral L1 protein mixed with recombinant viral proteins – As of now, no licensed HPV vaccine uses mRNA technology. mRNA vaccines (like Pfizer-BioNTech and Moderna for COVID-19) are a newer platform. Research is ongoing for mRNA-based HPV vaccines, but they are still in preclinical or early clinical stages. Current successful HPV vaccines (Gardasil, Cervarix) use recombinant protein subunit technology, not mRNA.
So, the correct answer is option C - L1 major capsid proteins self-assembled into virus-like particles (VLP)
