Background Emerging evidence argues that monocytes, circulating innate immune cells, are principal players in COVID-19 pneumonia. The study aimed to investigate the role of soluble (s)CD163 and sCD14 plasmatic levels in predicting disease severity and characterize peripheral blood monocytes and dendritic cells (DCs), in patients with COVID-19 pneumonia (COVID-19 subjects). Methods On admission, in COVID-19 subjects sCD163 and sCD14 plasmatic levels, and peripheral blood monocyte and DC subsets were compared to healthy donors (HDs). According to clinical outcome, COVID-19 subjects were divided into ARDS and non-ARDS groups. Results Compared to HDs, COVID-19 subjects showed higher sCD163 (p<0.0001) and sCD14 (p<0.0001) plasmatic levels. We observed higher sCD163 plasmatic levels in the ARDS group compared to the non-ARDS one (p=0.002). The cut-off for sCD163 plasmatic level greater than 2032 ng/ml was predictive of disease severity (AUC: 0.6786, p=0.0022; sensitivity 56.7% [CI: 44.1–68.4] specificity 73.8% [CI: 58.9–84.7]). Positive correlation between plasmatic levels of sCD163, LDH and IL-6 and between plasmatic levels of sCD14, D-dimer and ferritin were found. Compared to HDs, COVID-19 subjects showed lower percentages of non-classical (p=0.0012) and intermediate monocytes (p=0.0447), slanDCs (p<0.0001), myeloid DCs (mDCs, p<0.0001), and plasmacytoid DCs (pDCs, p=0.0014). Compared to the non-ARDS group, the ARDS group showed lower percentages of non-classical monocytes (p=0.0006), mDCs (p=0.0346), and pDCs (p=0.0492). Conclusions The increase in sCD163 and sCD14 plasmatic levels, observed on hospital admission in COVID-19 subjects, especially in those who developed ARDS, and the correlations of these monocyte/macrophage activation markers with typical inflammatory markers of COVID-19 pneumonia, underline their potential use to assess the risk of progression of the disease. In an early stage of the disease, the assessment of sCD163 plasmatic levels could have clinical utility in predicting the severity of COVID-19 pneumonia.
【저자키워드】 Monocytes, SARS-CoV-2, dendritic cells, pDCs, mDCs, flow cytometry, ELISA, 【초록키워드】 COVID-19, Monocytes, ARDS, COVID-19 pneumonia, Pneumonia, IL-6, disease severity, LDH, risk, D-dimer, ferritin, progression, dendritic cells, pDCs, mDCs, monocyte, Peripheral blood, Clinical outcome, Non-classical monocytes, sensitivity, specificity, severity of COVID-19, immune cells, Innate immune cells, Hospital admission, Inflammatory marker, correlation, Admission, early stage, dendritic cell, marker, Evidence, plasmacytoid DCs, on admission, Predictive, Activation, healthy donors, subject, positive correlation, clinical utility, correlations, circulating, CD163, cut-off, intermediate monocytes, peripheral blood monocytes, DCs, healthy donor, Result, greater, the disease, subjects, increase in, groups, subset, mDC, non-classical monocyte, patients with COVID-19, pDC, percentage, plasmacytoid DC, 【제목키워드】 COVID-19, Monocytes, dendritic cells, myeloid, Depletion, peripheral, Level, Increased,