New study: New coronavirus-specific immune T cells can also be detected in uninfected populations.

The new coronavirus (COVID-19), caused by the new coronavirus (SARS-CoV-2), is still prevalent worldwide.
currently known to have six coronaviruses that can infect humans, in addition to SARS-CoV-2, and these viruses trigger antibodies and T-cell reactions in infected patients.
understanding of the memory T cells that may exist in the human body to recognize SARS-CoV-2 is extremely important because previouspathogen-induced memory T cells can affect the susceptibility and clinical severity of the virus in subsequent societies.
July 15, 2020, a team of researchers from the Duke-Singapore National University School of Medicine published the latest research results of COVID-19 in Nature, revealing for the first time the presence of structural (nuclear-co-protein, NP) and non-structural (ORF1 NSP-7 and NSP13) regions of THE NC-19, and the presence of T-cells in the identifiable NP protein CD4 and CD8.
unexpected, the SARS-CoV-2-specific T-cell was also detected in uninfected populations, and the specific T cells in SARS rehabilitation patients had strong cross-reaction stoicism with SARS-CoV-2.
this suggests that beta-coronavirus infection induces the body to produce multispecific and long-lasting T-cell immunity to the structural protein NP.
to study SARS-CoV-2-specific T cells, researchers collected a total of 36 peripheral blood from mild to severe COVID-19 recovering individuals, and studied the cell's response to selected structural (nuclear shell protein-NP) and non-structural proteins in the SARS-CoV-2 protein group, which are highly homologous or even completely homologous between different beta coronaviruses.
researchers found that in almost all individual individual susmogenic blood cells (PBMCS) can identify NP-specific responses for multiple regions of SARS-CoV-2, from which clear CD4 and/or CD8 T cell groups are detected, resulting in IFN-stou and/or TNF-alpha.
the sars-cov-2-specific response in patients with COVID-19 rehabilitation, the researchers explored whether this acquired immunity could be sustained.
they collected PBMC 17 years after SARS-CoV-1 infection from 23 SARS-recovered patients and tested whether they still had cells that were reactive to SARS-CoV-1 and whether they were cross-reactive to SARS-CoV-2.
results show that after 17 years of SARS recovery, there are still specific T-cells in the human body that produce IFN-gamma reactions to SARS-CoV-1, and are concentrated almost exclusively in the NP region.
, 7 PBMCs of SARS-CoV-2 NP peptides produce clear and robust amplification of reactive cells, i.e. cross-reactive to SARS-CoV-2.
this suggests that viral-specific T cells caused by beta-coronavirus infection are long-term, and that persistent T-cells produced after the associated viral infection may be able to prevent or alter the pathology caused by SARS-CoV-2 infection.
SARS-CoV-2 cross-reaction sexist in SARS rehabilitation patients to explore this possibility, the researchers in 37 SARS-CoV-1 / 2 unexposed individuals tested their SARS-CoV-2 NP and NSP7 / 13 peptides of reactive IFN-gamma reaction, found that 19 can detect SARS-CoV-2 specific IFN-gamma reaction, that is, specific if-type sars-2-2- Further research
found that SARS-CoV-2 T cells in uninfected people showed different patterns of immune advantage, mainly targeting NP structural proteins and ORF-1-encoded proteins NSP7 and 13.
the epitope of NSP7-specific T-cells showed low-homogenic protein fragments associated with the "common cold" human coronavirus, but were conservative in animal beta coronaviruses.
immune advantages of SARS-CoV-2 responses in uninfected individuals, researchers said the study helps to understand how existing NP and ORF-1-specific T cells in the general population affect susceptibility and pathogenesis of SARS-CoV-2 infection, which is critical to the management of the current COVID-19 pandemic.
References: SARS-CoV-2-specific T cell immunity in case of COVID-19 and SARS, and uninfected controls.