“Pan-coronavirus” vaccines: RNA Polymerase Emerges as a Vaccine Target

Date:

Share post:

Resistance to COVID-19 infection has been observed in health care workers and has been attributed to the presence of memory T cells that target the RNA polymerase in the RTC (replication transcription complex), thereby preventing infection. This makes RNA polymerase an important target for making a pan-coronavirus vaccine that will be effective against SARS-CoV-2 and its other variants of concern (VoC’s), but also against the family of Coronaviruses in general. 

COVID-19 pandemic is now almost 2 years old and has caused havoc among the world by disrupting world economy and halting the normal way of living. Millions have died and many more have been infected with the disease leading to high levels of morbidity. However, there have been instances where people have cleared the infection from the system so quickly that they didn’t test positive for the virus or developed antibodies against it. This resistance has been attributed to the memory T cells-possibly those that are produced after exposure of the human system to such viruses. 

In a recent study published in Nature by Swalding et al., blood samples from 60 health care workers, who were at high risk of developing COVID-19 due to their exposure, were examined and found out to be negative for the virus and for the antibodies against the virus1. It is hypothesised that pre-existing memory T-cells, with cross-protective potential against SARS-CoV-2, expand in vivo to provide rapid viral clearance, thus aborting infection. These T cells are directed against the RNA polymerase in the RTC (replication transcription complex), rather than any other structural protein of the virus. These memory T cells could have been generated in the health care workers by being exposed to other respiratory or related corona viruses, albeit there is no direct evidence of the same. It is also possible that there were other environmental triggers that led to the generation of these T cells. In addition, these sero-negative individuals also showed an increase in IFI27, a protein indicative of abortive SARS-CoV-2 infection. IFI27 is an interferon alpha inducible protein that is overexpressed upon exposure to a variety of respiratory viruses, including SARS-CoV-2. This may also be responsible for viral clearance in individuals, pre-exposed to other respiratory viruses, and then infected with SARS-CoV-2. 

The fact that the memory T cells are directed against the RNA polymerase (being the most conserved among the human coronaviruses that cause common cold and SARS-CoV-2), makes this enzyme an important target to develop a pan-coronavirus vaccine that would not only be directed against SARS-CoV-2 and its other variants of concern (VoC’s) that have evolved as a result of mutations in the spike protein leading to more severe disease, but also against the family of Coronaviruses in general. 

*** 

Source:  

Swadling, L., Diniz, M.O., Schmidt, N.M. et al. Pre-existing polymerase-specific T cells expand in abortive seronegative SARS-CoV-2. Nature (2021). https://doi.org/10.1038/s41586-021-04186-8 

***

Rajeev Soni
Rajeev Sonihttps://www.RajeevSoni.org/
Dr. Rajeev Soni has a Ph.D. in Biotechnology from the University of Cambridge, UK and has 25 years of experience working across the globe in various institutes and multinationals such as The Scripps Research Institute, Novartis, Novozymes, Ranbaxy, Biocon, Biomerieux and as a principal investigator with US Naval Research Lab in drug discovery, molecular diagnostics, protein expression, biologic manufacturing and business development.

LEAVE A REPLY

Please enter your comment!
Please enter your name here

For the benefit of students and readers (neural translation of) Scientific European is available in many languages

Deutsch Română
Français Nederlands
Русский Português
简体中文 Italiano
日本語 Български
Español Filipino
हिन्दी ગુજરાતી
العربية தமிழ்
Ελληνικά اردو
বাংলা MORE

Related articles

Stem Cell Models of Diseases: First Model of Albinism Developed

Scientists have developed the first patient-derived stem cell model of albinism. The model will help studying eye conditions...

Mars Orbiter Mission (MOM) of ISRO: New Insight into Prediction of Solar Activity

The researchers have studied the turbulence in Sun’s corona using radio signals sent to Earth by the ultra-low-cost...

‘‘A living WHO guideline on drugs for COVID-19’’: The Eighth version (Seventh update) Released

The eighth version (seventh update) of a living guideline is released. It replaces earlier versions. The latest update...

….Pale Blue Dot, the only Home We’ve Ever Known

''....astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human...