According to a new study conducted by researchers from the University of Melbourne, Monash University, and James Cook University, the novel coronavirus can compromise the activation of the CD8+ T-cell responses that help in fighting various respiratory diseases.
The study was published in medRxiv. It stated that SARS-CoV-2 infection does stimulate CD4+ T-cell responses but these responses are ten times lower in the case of Covid-19.
More research needed
Katherine Kedzierska and team found that further research is needed to provide a more detailed picture of CD8+ T-cell responses in Covid-19 since priming with an appropriate vaccine could be highly valuable in terms of optimising protective CD8+ T-cell immunity.
The researchers noted that although the majority of infections only cause mild disease and are short-lived, 12 to 18 per cent of patients with Covid-19 develop severe disease and require hospitalisation.
Furthermore, of those who do develop mild disease or are even asymptomatic, the underlying pathology may still be present.
Virus-specific CD8+ T-cells are generally thought to play a role in clearing viral infection in the acute immune response to respiratory infection, where an established CD8+ T-cell memory response provides future protection against severe disease.
Survivors of the 2002 SARS-CoV-1 outbreak, for example, still maintain CD4+ and CD8+ cells that are specific to the virus, the authors stated.