The outbreak of the SARS-CoV-2 virus in December 2019 has caused the deaths of several hundred thousand people worldwide. Currently, the pathogenesis of COVID-19 is poorly understood. During the course of COVID-19 infection, many patients experience deterioration, which might be associated with systemic inflammation and cytokine storm syndrome; however, other patients have mild symptoms or are asymptomatic. There are some suggestions that impaired cellular immunity through a reduction in Th1 response and IFNG (interferon gamma) expression, as well as cross-reactivity with common cold coronaviruses, might be involved in the differential COVID-19 course. Here, we show that CD4+ cells isolated from unexposed healthy donors that were differentiated towards the Th1 lineage in the presence of SARS-CoV-2 proteins exhibited induction of IFNG . Interestingly, the same cells induced to differentiate towards a Th17 lineage did not exhibit changes in IFNG expression or Th17-related cytokines. This suggests the cellular response to SARS-CoV-2 viral proteins is primarily associated with Th1 lymphocytes and may be dependent on past infections with common cold coronaviruses or vaccinations that induce unspecific cellular responses, e.g., BCG ( B acillus C almette- G uérin). Thus, our results might explain the high variability in the course of COVID-19 among populations of different countries.
【저자키워드】 COVID-19, SARS-CoV-2, Th1, Th17, IFN-γ, IFNg, 【초록키워드】 Cytokine storm, vaccination, Cytokines, Infection, Population, cross-reactivity, Protein, Deterioration, Asymptomatic, COVID-19 infection, outbreak, BCG, Patient, Lineage, death, systemic inflammation, expression, cellular response, interferon gamma, Cellular responses, Impaired Cellular Immunity, Mild symptom, common cold coronavirus, pathogenesis of COVID-19, high variability, SARS-CoV-2 protein, common cold Coronaviruses, CD4+ cell, Cell, healthy donor, SARS-CoV-2 viral, Course, caused, involved, exhibited, changes in, dependent on, induce, reduction in, explain, Th1 lymphocyte, Th1 response, the SARS-CoV-2 virus, 【제목키워드】 CD4+,