ccmb-develops-indian-mrna-vaccine-platform

Context-

The Centre for Cellular and Molecular Biology (CCMB) established the “proof of principle” of the development of the first mRNA vaccine technology indigenously in India.

Highlights-

  • It is based on the Moderna model, but is built using own technology and materials based on open source informations
  • It is observed that a high immune response is generated against the COVID­19 spike protein introduced in mice upon administration of two doses of the mRNA vaccine. 
  • The antibodies generated were more than 90% efficient in preventing the human ACE2 receptor from binding to the coronavirus
  • The tested vaccine is now undergoing preclinical hamster challenge to evaluate the efficacy against live virus infection. 
  • The indigenous vaccine platform is expected to successfully deal with other infectious diseases like TB, dengue, malaria, chikungunya, rare genetic diseases and others. 
  • The main selling point of this technology is in its rapid turnaround times, which means vaccines can be developed for other diseases or suppose a covid vaccine covering all covid variants.
  • As per scientists the technology is ready to be taken to the next level of human trial and they welcomed all private players in this sphere to collaborate in this regard
  • Normally vaccines work by training the immune system to identify disease­ causing micro­organisms and in that way prepares the body to attack and eliminate them. But in this new mRNA technology, the host cell’s immune system is trained to evade the real infection by introducing mRNA of the micro­organism into the body of the host

Various types of vaccine technologies-

There are three main approaches to designing a vaccine. Their differences lie in whether they use a whole virus or bacterium; just the parts of the germ that triggers the immune system; or just the genetic material that provides the instructions for making specific proteins and not the whole virus.

The whole-microbe approach

Inactivated vaccine

  • The first way to make a vaccine is to take the disease-carrying virus or bacterium, or one very similar to it, and inactivate or kill it using chemicals, heat or radiation. This approach uses technology that’s been proven to work in people – this is the way the flu and polio vaccines are made – and vaccines can be manufactured on a reasonable scale. 
  • However, it requires special laboratory facilities to grow the virus or bacterium safely, can have a relatively long production time, and will likely require two or three doses to be administered.

Live-attenuated vaccine

  • A live-attenuated vaccine uses a living but weakened version of the virus or one that’s very similar. The measles, mumps and rubella (MMR) vaccine and the chickenpox and shingles vaccine are examples of this type of vaccine. This approach uses similar technology to the inactivated vaccine and can be manufactured at scale. However, vaccines like this may not be suitable for people with compromised immune systems.

Viral vector vaccine

  • This type of vaccine uses a safe virus to deliver specific sub-parts – called proteins – of the germ of interest so that it can trigger an immune response without causing disease. To do this, the instructions for making particular parts of the pathogen of interest are inserted into a safe virus. The safe virus then serves as a platform or vector to deliver the protein into the body.  The protein triggers the immune response. The Ebola vaccine is a viral vector vaccine and this type can be developed rapidly.

The subunit approach

  • A subunit vaccine is one that only uses the very specific parts (the subunits) of a virus or bacterium that the immune system needs to recognize. It doesn't contain the whole microbe or use a safe virus as a vector. The subunits may be proteins or sugars. Most of the vaccines on the childhood schedule are subunit vaccines, protecting people from diseases such as whooping cough, tetanus, diphtheria and meningococcal meningitis.

The genetic approach (nucleic acid vaccine)

  • Unlike vaccine approaches that use either a weakened or dead whole microbe or parts of one, a nucleic acid vaccine just uses a section of genetic material that provides the instructions for specific proteins, not the whole microbe. DNA and RNA are the instructions our cells use to make proteins. In our cells, DNA is first turned into messenger RNA, which is then used as the blueprint to make specific proteins. 
  • A nucleic acid vaccine delivers a specific set of instructions to our cells, either as DNA or mRNA, for them to make the specific protein that we want our immune system to recognize and respond to. 
  • The nucleic acid approach is a new way of developing vaccines. Before the COVID-19 pandemic, none had yet been through the full approvals process for use in humans, though some DNA vaccines, including for particular cancers, were undergoing human trials. Because of the pandemic, research in this area has progressed very fast and some mRNA vaccines for COVID-19 are getting emergency use authorization, which means they can now be given to people beyond using them only in clinical trials.

List of all vaccines which have received Emergency Use Listing by World Health Organisation (WHO)-

Name

Type

Developed by

Nuvaxovid

Protein Subunit

Novovax

Covovax

Protein Subunit

Serum Institute of India

Spikevax

mRNA

Moderna

Comirnaty

mRNA

Pfizer BioNTech

Janssen

Non replicating viral vector

Johnson and Johnson

Vaxzevria

Non replicating viral vector

Oxford Astrazeneca

Covisheild

Non replicating viral vector

Serum Institute of India

Covaxin

Inactivated

Bharat Biotech

Covilo

Inactivated

Sinopharm

Coronavac

Inactivated

Sinovac