Immune characteristics of severe and critical COVID-19 patients

Abstract

Dear Editor, Recently, the novel coronavirus disease (COVID-19) has broken out worldwide, 1 with rapid increase of infected patients. COVID-19 dominantly leads to pneumonia. 2 Among these COVID-19 patients, some appears to be severe symptoms with acute respiratory distress syndrome, organ failure, 2 and further present a poor outcome. Previous studies have been reported that immune patterns are closely associated with disease progression of patients infected with other viruses. 3 The correlation between immune signatures and outcome of severe and critical COVID-19 cases was not well illuminated. Therefore, we aimed to evaluate the correlation between immune characteristics, especially levels of lymphocytes and cytokines in peripheral blood, and clinical parameters in severe and critical COVID-19 patients, in order to find critical indicators of disease progression and to provide important guides for therapeutic strategy. Thirty-six adult cases with severe and critical COVID-19 were enrolled. The disease outcome, immune patterns, microbiota infection, coagulation profile, and organ dysfunction biomarkers were analyzed and collected. This project was approved by the Ethics Committee of our hospital (No. 2020-KY-060), and all patients signed the informed consent. We found that the cell numbers of lymphocytes in these patients were obviously decreased compared to that in healthy donors, including total lymphocytes, total T, CD4 + T, CD8 + T, B and NK cells (Fig. 1a), and the percentage of lymphocytes in COVID-19 patients was also significantly decreased except B cells (Supplementary Fig. S1a, b), with an increased ratio of CD4 + /CD8 + T cells (Supplementary

Prolonged humoral and cellular immunity in COVID-19-recovered patients

“…Lymphocytopenia is a prevalent COVID-19 marker, with reduced NK cell counts reported during infection ( Yang et al, 2020 ). The NK cell numbers were analyzed to determine whether any long-term decrease in NK cell numbers occurs as a result of SARS-CoV-2 infection and whether post-infection changes in NK cell numbers are associated with the severity of the clinical disease manifestation.…”

Nutritional Support and Clinical Outcome of Severe and Critical Patients With COVID-19 Pneumonia

“…Elimination of the virus mainly depended on the autoimmune system of patients. A recent study reported SARS-CoV-2 pneumonia patients with high lymphocyte levels, excluding B cells, and with low Interleukin-6 (IL-6) or Interleukin-10 (IL-10) levels, had a better survival rate (21). Early nutritional intervention could enhance the therapeutic effect of severe pneumonia patients with ARDS and reduce systemic inflammatory response (22,23).…”

COVID-19 and Cardiovascular Disease

“…Lymphopenia in COVID-19 predominantly reflects T cell depletion, whereas B cell numbers are preserved. 127 Naive T cells tend to be diminished in the elderly, a finding associated with a poor prognosis. 128 Greater disease severity is also associated with lower levels of circulating spike-specific TfH cells and lower numbers of CD8+ IFNg+ T cells, whereas T17 cells were not generally detected.…”