Dynamics of cytokines and lymphocyte subsets associated with the poor prognosis of severe COVID-19.

We aimed to study the dynamics of cytokines and lymphocyte subsets and their correlation with the prognosis of patients with severe COVID-19.The lymphocyte subsets and cytokines of 31 patients with severe COVID-19 (7 deaths and 24 survivals) were longitudinally analyzed.The mean age of enrolled patients was 64 years, 24 (77.4%) patients were men, and 23 (74.2%) patients had comorbidities. Compared with survival group, the death group showed significant and sustained increases in the levels of IL-6, IL-8, and IL-10 from baseline to 28 days after admission (all p<0.05). No significant differences were observed in the levels of TNF-α, IL-1b, IL-2, IL-4, IL-5, IL-12P70, IL-17, IFN-α, and IFN-γ between the death group and survival group during the follow-up (all p>0.05). The absolute counts of CD3+ T cells, CD4+ T cells, CD8+ T cells, and CD45+ T cells were lower in both survival group and death group patients from hospital admission to 3 days after admission, and gradually recovered in 4 to 35 days in the survival group, but continually stayed at low levels in the death group during the follow-up.The kinetic changes of cytokines and lymphocyte subsets are related with the prognosis of patients with severe COVID-19.