This is not the first paper discussing the influence of cold on COVID-19 infection in the past. The international academic journal Nature also published a paper on COVID-19, pointing out that the common cold in the past may affect the severity of COVID-19's disease. Because the global epidemic situation is still high and the common cold is so common, this paper immediately gained great attention.
According to a paper in the journal Nature, past infections may lead to a "cross-reaction" of infection in COVID-19. Generally speaking, this may play a protective role; However, there is another possibility that the disease may be aggravated, that is, after the immune system accelerates the production of antibodies, it will cause antibody dependence (ADE), which will aggravate the disease. Therefore, at that time, researchers were not sure whether a cold was good or bad for COVID-19 patients.
The common cold helps T cells remember the virus. In this new study, a research team of La Jolla Institute of Immunology (LJI) further pointed out that the severity of COVID-19 patients' diseases may be related to whether they have been attacked by common cold coronavirus before, because memory T cells that recognize common cold coronavirus can also recognize matching sites on novel coronavirus, thus enabling the immune system to cope with novel coronavirus faster and better.
Alessandro Sette, a co-author of the report and a professor at LJI University, said: "The immune response may translate into different degrees of protection. Having a strong T cell response or a better T cell response can give patients with coronavirus pneumonia-19 a chance to have a faster and stronger response. 」
Previously, a research report published by the team in Cell magazine suggested that people who are not infected with coronavirus pneumonia-19 may have a 40% to 60% probability of detecting COVID-19-specific immune T cells in their bodies, and this phenomenon has been reported in the Netherlands, Germany, Britain and Singapore.
Coronavirus, including HCoV-OC43, HCoV-HKU 1, HCoV-NL63 and HCoV-229E, can cause mild upper respiratory diseases and cause cold-like symptoms. Researchers speculate that these coronaviruses are novel coronavirus's "low-risk cousins", and the T cells found in healthy people may be caused by their previous infection with common cold coronaviruses, and the immune system retains the memory response to these coronaviruses.
In short, this study provides direct evidence that fighting a common cold coronavirus can really teach T cells to recognize some parts of COVID-19, and provides evidence that common cold virus can induce T cells to cross-react with COVID-19.
Seth said: "We know that reactivity existed before, and this study provides very strong direct molecular evidence that memory T cells can' see' very similar sequences between common cold coronavirus and novel coronavirus. In the future, the potential of this cross-reactivity will be utilized and the effectiveness of the vaccine will be further improved. "