The total market worth of the vaccines was 30 billion USD in 2016 and is expected to increase to 45 billion in 2022 (1). Vaccines have become a critical part of our lives and saves us from many life threatening infectious diseases caused by viruses and bacteria. The indispensability of the vaccines can be understood by the fact that in 40-70 million people were killed worldwide due to influenza pandemic in 1918-19.
Better understanding of science involved in these infectious diseases and development of cutting edge molecular biology and synthetic biology tools have revolutionized the field of vaccine design. In the last decade the time to develop vaccine against a new pathogen has reduced from six month to 100 hours (2,3,4). The reports from 2016 mention that 250 vaccine developments including clinical trials were in pipeline from USA (5).
With such an increase in the speed of designing and developing vaccine we have been successful in stopping the pandemic situations against novel pathogens. The next challenge is to produce the vaccine in large quantity for mass vaccination of the population, says Dr. Ashish Sharma, a visiting fellow scientist at National Institutes of Health, USA. He completed his Ph.D. at School of Biotechnology, Jawaharlal Nehru University, India. The large scale production of vaccines requires working with big bioreactors and running them with optimized process parameters, which has been practised for several years.
But very little research has been done to understand the microbe which is producing vaccines in those big reactors. ‘During my Ph.D. I learned to understand and analyze what happens inside the bacteria when we try to produce recombinant proteins e.g. recombinant vaccines. My findings (and published a research paper(6) which) essentially proved that expressing different recombinant protein/vaccine has a different type of impact on bacteria’, says Dr. Ashish Sharma. Several vaccines have been produced in different organisms like E.coli, Bacillus, Pichia, etc with the help of recombinant DNA (synthetic biology) techniques.
The biggest problem with this strategy is that the microbes produce a very little amount of vaccines and is often degraded or not in active form. This is one of the critical issues vaccine production industries are facing and remains a challenge. Indeed, understanding the microbial cellular responses will help in finding out the reasons why microbes don’t express enough of vaccines and once you find out the reasons, then issues can be fixed with the state of art molecular biology tools, says Dr. Ashish Sharma. He mentioned that by implementing his findings he has been able to successfully increase the production amounts in the lab scale experiments. He recently published his research finding in one the ‘Nature Scientific Reports Journal’, where strategies to increase the anthrax vaccine (recombinant protective antigen) in bioreactors were identified (7).
It is interesting to know that there is only one FDA approved anthrax vaccine available in USA. Same is the situation with the many other vaccines and so they are very costly, under such circumstances if we can produce these vaccines in large quantities with minimal cost, it will definitely bring down the cost and will be affordable to general public.