Scientists at La Jolla Institute for immunology in California have concluded that patients with a stronger immune response to the coronaviruses that cause cold-like symptoms may be “better protected against covid-19″. This offers the hope that a pan-coronavirus vaccine might be within reach. As researchers scramble to find novel methods of providing immunity, these results provide exciting potential. 

An article in New Scientist states that the study analysed blood samples collected before the emergence of covid-19. Multiple samples were collected from each patient over 6 months to 3 years. The team explored the response of the immune cells in these samples to four coronaviruses as well as the SARS-CoV-2 strain. They combined the blood with peptides from the coronaviruses and measured the T-cell and antibody responses that resulted. They found the responses to be “stable and persistent for all four” of the coronaviruses. Furthermore, they established that the immune responses were not due to “regular re-infections”.  

Next, researchers combined the samples with SARS-CoV-2. This revealed that the samples with the stronger T-cell immune responses to the previous four coronaviruses had the strongest response to SARS-CoV-2. However, this wasn’t the same for antibody levels.  

Dr Ricardo da Silva Antunes of La Jolla Institute stated the importance of using pre-pandemic samples. This enabled the researchers to see “pre-existing immune memory”. The genetic similarity of SARS-CoV-2 to the four common cold-like coronaviruses invited the possibility that T-cell responses “induced by prior coronaviruses” might protect against the current SARS-CoV-2.  

Despite these findings, Dr da Silva Antunes says that the “link” between these two categories of coronavirus is “still not clear”. The participants with stronger immune responses to the common cold-like coronaviruses were not guaranteed to experience less severe covid-19.  

For Professor Mala Maini of University College London, these findings add to the growing evidence that T-cell immune responses to common cold-like coronaviruses influence our SARS-CoV-2 responses. She and her colleagues are working towards a pan-coronavirus vaccine. In 2021 she stated that a “vaccine that can induce T-cells to recognise and target infected cells expressing [replication proteins]” might be able to eliminate “early SARS-CoV-2″ as well as “other coronaviruses” that will infect humans in the future.  

To learn about approaches to developing a pan-coronavirus vaccine get your tickets to the World Vaccine Congress in Europe 2022.