Previous Encounter with Cold Coronavirus may Protect Novel Coronavirus Infections too: an Intriguing New Report

Dr. Shuvomoy Banerjee, PhD, from Neucrad Health desk; August 9, 2020

Science says that when a person gets infected with common cold Coronavirus, antibodies as well as ‘memory T-cells’ are generated in the body which are crucial for the immune system to protect from several other similar viral infections. Surprisingly, a recent study has recently claimed that it may also offer protection in case of novel Coronavirus infections!

common Cold Coronavirus infection is very familiar during seasonal changes when people suffer from mild cold and cough symptoms  but also recovers within a few days. There are 4 such Coronaviruses responsible for the common cold. Interestingly, novel Coronavirus (or the Covid-19 responsible SARS-CoV2) has been described as a “cousin” of cold Coronavirus only, as they both belong to the same family of Coronavirus!

A common question that has crossed all the scientific minds during the Covid-19 pandemic is why some people with novel corona virus infection showed severe and even life-threatening symptoms while the rest infected showed mild symptoms!  What would be the scientific explanation for these two extreme situations?

Of note, the production and probable function of the memory T-cells produced as a result of infection by all these Coronaviruses have caused immense curiosity in the scientific community and one recent report have sparked some excitement. Dr. Daniela Weiskopf and Dr. Alessandro Sette, two professors from the La Jolla Institute of Immunology (LJI), United States recently published in Science journal where they provided experimental evidence to prove that subsequent production of memory T-lymphocytes as a result of common cold Coronavirus infection build the resistance against the SARS-CoV-2 viral infection as well!

Previously, Dr. Alessandro Sette and LJI Professor Dr. Shane Crotty have jointly conducted a research work foundthat 40-60% of people worldwide who have never experienced Covid-19 has already some memory T-lymphocytes in their bodies and which might be crucial to fight SARS-CoV-2 virus! The study was based on the people from the United States, Netherlands, Germany, Britain and Singapore and the work has been published in the prestigious journal Cell.  For their research work, Dr. Sette and his researchers collected blood samples from people who were infected with the common cold virus between 2015 and 2018 and recovered completely thereafter. In the laboratory, T-lymphocytes are isolated from these samples and tested for the reactivity of memory T-lymphocytes.  Their wonderfully designed experiment demonstrated that these T-lymphocytes can easily identify 142 specific “special sites” in the corona virus. Surprisingly, about half of these are located in the Spike-protein (S-Protein) of the virus. Dr. Sette’s investigations revealed that the genetic sequences in ‘special sites’ of common cold Coronavirus are exactly the same as those of the novel Coronavirus. Therefore, Scientists have a strong speculation that infection with the common cold Coronavirus gives the body’s immune system a special “education” to generate specific memory T-lymphocytes which if necessary, can prevent Covid-19 in the future (due to their some structural similarities). This piece of scientific finding has enormous importance in vaccine research because the current trend represents to generate Covid-19 vaccine against the SARS-CoV-2 spike protein mostly. In addition, other ‘epitopes’ of the novel Coronavirus should thoroughly reviewed which will surely add a new dimension in recent Covid-19 vaccine development.

It should be noted that Dr. Sette speculates on the immune reactivity which may translate to different degrees of protection during infection.   Henceforth, the possibility that even though our immune system has never ‘seen’ the SARS-CoV-2 virus before, it may still be able to cross-recognize some parts of its entire molecular structure and fight back to protect us has raised our hopes.

Featured Image credit: Paranjoy Ghosh, Age: 8 years

References:

1. Mateus J, Grifoni A, Tarke A, et al. Selective and cross-reactive SARS-CoV-2 T cell epitopes in unexposed humans [published online ahead of print, 2020 Aug 4]. Science. 2020;eabd3871. doi:10.1126/science.abd3871
2.  Grifoni A, Weiskopf D, Ramirez SI, et al. Targets of T Cell Responses to SARS-CoV-2 Coronavirus in Humans with COVID-19 Disease and Unexposed Individuals. Cell. 2020;181(7):1489-1501.e15. doi:10.1016/j.cell.2020.05.015
3. Le Bert N, Tan AT, Kunasegaran K, et al. SARS-CoV-2-specific T cell immunity in cases of COVID-19 and SARS, and uninfected controls [published online ahead of print, 2020 Jul 15]. Nature. 2020;10.1038/s41586-020-2550-z. doi:10.1038/s41586-020-2550-z
4. Peng Y, Mentzer AJ, Liu G, et al. Broad and strong memory CD4 ⁺ and CD8 ⁺ T cells induced by SARS-CoV-2 in UK convalescent COVID-19 patients. Preprint. bioRxiv. 2020;2020.06.05.134551. Published 2020 Jun 8. doi:10.1101/2020.06.05.134551
5. Braun J, Loyal L, Frentsch M, et al. SARS-CoV-2-reactive T cells in healthy donors and patients with COVID-19 [published online ahead of print, 2020 Jul 29]. Nature. 2020;10.1038/s41586-020-2598-9. doi:10.1038/s41586-020-2598-9
6. Cascella M, Rajnik M, Cuomo A, Dulebohn SC, Di Napoli R. Features, Evaluation and Treatment Coronavirus (COVID-19). In: StatPearls. Treasure Island (FL): StatPearls Publishing; July 4, 2020.
7. https://www.eurekalert.org/pub_releases/2020-08/ljif-etc080320.php