The story so far: The Pune-based Gennova Biopharmaceuticals is expected to roll out India’s first home-grown mRNA (messenger ribonucleic acid) vaccine by April. The COVID-19 pandemic awakened the world to the power of RNA therapies — two of the first vaccines that emerged in late 2020, Pfizer-BioNtech and Moderna, used this technology. Now, an Indian company is developing an mRNA vaccine from scratch, signalling possibilities of the use of the molecule in a variety of diseases beyond COVID-19.
What is a mRNA vaccine?
Like other vaccines, the mRNA vaccine strives to activate the immune system to produce antibodies that help counter an infection from a live virus. While the traditional method to do this involves introducing a part or the whole virus in a way that it cannot replicate, there is always the risk of an adverse reaction in the case of the SARS-CoV-2 virus. Hence, a quest of vaccinology has been to tease out an immune response that is effective but also relatively safe. The theory goes that the less of a foreign body injected, the fewer the odds of an adverse response. A common approach by vaccine makers during the pandemic was to introduce a portion of the spike protein, the key part of the coronavirus, as part of a vaccine. Some makers, such as those that made the Oxford University vaccine (AstraZeneca) or Sputnik V, wrapped the gene that codes for the spike protein into an inactivated virus that affects chimpanzees, called the chimpanzee adenovirus. The aim is to have the body use its own machinery to make spike proteins from the given genetic code. The immune system, when it registers the spike protein, will create antibodies against it. Other vaccines use a piece of DNA to envelope the spike protein genes. An mRNA vaccine works in similar ways in that it too is a piece of genetic code inserted into the body to stimulate an immune response.
