mRNA technologies for Vaccine production

The World Health Organization has announced that six African countries will be given the revolutionary mRNA technology to set up their own vaccine production centers helping the continent acquire self-reliance against the Covid pandemic.

• Researchers have been studying and working with mRNA vaccines for decades.
• Interest has grown in these vaccines because they can be developed in a laboratory using readily available materials.
• This means vaccines can be developed and produced in large quantities faster than with other methods for making vaccines.
• mRNA vaccines have been studied before for flu, Zika, rabies, and cytomegalovirus (CMV). As soon as the necessary information about the virus that causes COVID-19 was available, scientists began designing the mRNA instructions for cells to build the unique spike protein into an mRNA vaccine.
• Future mRNA vaccine technology may allow for one vaccine to provide protection against multiple diseases, thus decreasing the number of shots needed for protection against common vaccine-preventable diseases.

What are vaccines?

• Vaccines help prepare the body to fight foreign invaders (pathogens such as bacteria or viruses), to prevent infection.
• All vaccines introduce into the body a harmless piece of a particular bacteria or virus, triggering an immune response.
• Most vaccines contain a weakened or dead bacteria or virus.

What are mRNA vaccines and how do they work?

• Scientists have developed a new type of vaccine that uses a molecule called messenger RNA (mRNA) rather than part of an actual bacteria or virus.
• Messenger RNA is a type of RNA that is necessary for protein production.
• In cells, mRNA uses the information in genes to create a blueprint for making proteins.
• Once cells finish making a protein, they quickly break down the mRNA.
• mRNA from vaccines does not enter the nucleus and does not alter DNA.
• mRNA vaccines work by introducing a piece of mRNA that corresponds to a viral protein, usually a small piece of a protein found on the virus’s outer membrane. (Individuals who get an mRNA vaccine are not exposed to the virus, nor can they become infected by the vaccine)
• Using this mRNA blueprint, cells produce the viral protein. As part of a normal immune response, the immune system recognizes that the protein is foreign and produces specialized proteins called antibodies.
• Antibodies help protect the body against infection by recognizing individual viruses or other pathogens, attaching to them, and marking the pathogens for destruction.
• Once produced, antibodies remain in the body, even after the body has rid itself of the pathogen, so that the immune system can quickly respond if exposed again.

Risks of the mRNA Vaccine:

• Some mRNA-based vaccine platforms induce potent interferon type I responses, which have been associated not only with inflammation but also potentially with autoimmunity.
• Thus, the identification of individuals at an increased risk of autoimmune reactions before mRNA vaccination may allow reasonable precautions to be taken.
• The risks associated with mRNA strands that did not manage to pass into a human cell are considered to be low, as the fragile mRNA molecule should be quickly broken down inside the body once its drug delivery system has eroded.
• mRNA vaccines are new, and before 2020, no mRNA technology platform had ever been authorized for human use, and thus there is the risk of unknown effects, both short and longer-term.

Advantages:

• As mRNA vaccines are not constructed from an active pathogen (or even an inactivated pathogen), they are non-infectious.
• mRNA vaccines can be produced faster, cheaper, and in a more standardized fashion which improves responsiveness to outbreaks.

Way Ahead:

• Researchers are studying how mRNA might be used to develop vaccines for additional infectious diseases.
• Moderna is developing an HIV vaccine based on similar technology, which will enter early clinical trials, with preliminary results expected in 2022.
• Biontech is developing a malaria vaccine based on messenger RNA technology, with clinical trials expected to start in 2022.