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Clinical Trial
. 2021 Jan;147(1):81-91.
doi: 10.1016/j.jaci.2020.09.009. Epub 2020 Oct 23.

Compartmental immunophenotyping in COVID-19 ARDS: A case series

Andreas Ronit  1 , Ronan M G Berg  2 , Jakob T Bay  3 , Anna K Haugaard  3 , Magnus G Ahlström  4 , Kristoffer S Burgdorf  3 , Henrik Ullum  3 , Sara B Rørvig  5 , Klaus Tjelle  6 , Nicolai B Foss  6 , Thomas Benfield  1 , Hanne Vibeke Marquart  3 , Ronni R Plovsing  7
Affiliations
Clinical Trial

Compartmental immunophenotyping in COVID-19 ARDS: A case series

Andreas Ronit et al. J Allergy Clin Immunol. 2021 Jan.

Abstract

Background: Severe immunopathology may drive the deleterious manifestations that are observed in the advanced stages of coronavirus disease 2019 (COVID-19) but are poorly understood.

Objective: Our aim was to phenotype leukocyte subpopulations and the cytokine milieu in the lungs and blood of critically ill patients with COVID-19 acute respiratory distress syndrome (ARDS).

Methods: We consecutively included patients less than 72 hours after intubation following informed consent from their next of kin. Bronchoalveolar lavage fluid was evaluated by microscopy; bronchoalveolar lavage fluid and blood were assessed by 10-color flow cytometry and a multiplex cytokine panel.

Results: Four mechanically ventilated patients (aged 40-75 years) with moderate-to-severe COVID-19 ARDS were included. Immature neutrophils dominated in both blood and lungs, whereas CD4 and CD8 T-cell lymphopenia was observed in the 2 compartments. However, regulatory T cells and TH17 cells were found in higher fractions in the lung. Lung CD4 and CD8 T cells and macrophages expressed an even higher upregulation of activation markers than in blood. A wide range of cytokines were expressed at high levels both in the blood and in the lungs, most notably, IL-1RA, IL-6, IL-8, IP-10, and monocyte chemoattactant protein-1, consistent with hyperinflammation.

Conclusion: COVID-19 ARDS exhibits a distinct immunologic profile in the lungs, with a depleted and exhausted CD4 and CD8 T-cell population that resides within a heavily hyperinflammatory milieu.

Keywords: Acute respiratory distress syndrome; COVID-19; bronchoalveolar lavage; cytokines; flow cytometry.

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Figures

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Graphical abstract
Fig 1
Fig 1
Radar plots of COVID-19 leukocyte subsets in blood (A) and BALF (B). Data from the same 4 patients are merged for blood (A) and BALF (B). Axis labels indicate the recognition antibody, and the cluster labels describe the gated cell population. Dim colored dots in clusters indicate activated cells (positive for CD69). BALF is dominated by myeloid cells. In healthy adults, monocytes comprise 65.3% to 95.4%, lymphocytes comprise 3.0% to 32.4%, neutrocytes comprise 0.2% to 4.3%, eosinophils comprise 0.1% to 3.5%, and basophils comprise 0.0% to 0.2% of leukocytes in BALF. CD4+ cells comprise 35% to 79%, CD8+ cells comprise 15% to 57%, B cells comprise 0.0% to 5.3%, and natural killer cells comprise 2% to 8% of the leukocytes. gd, γδ.
Fig 2
Fig 2
Absolute number and proportion of lymphocyte subpopulations in the blood and BALF. A, Absolute number of lymphocyte subpopulations in the blood of patients (yellow symbols) and healthy controls (gray circles). B, Proportion of lymphocyte subpopulations in BALF (blue symbols) and blood (yellow symbols) of patients and healthy controls (blood only, gray circles). Colored symbols (circle, square, triangle, and diamond) represent the same patient within the different subpopulations and within the 2 compartments (blue indicates BALF; yellow indicates blood). The box plot represents the median and interquartile range for healthy controls (n = 22). NK, Natural killer.
Fig 3
Fig 3
Lymphocyte differentiation in blood. A, Proportion of CD4 T-cell subpopulations in blood of patients (yellow symbols) and healthy controls (gray circles), B, Proportion of CD8 T-cell subpopulations in blood of patients (yellow symbols) and healthy controls (gray circles). Yellow symbols (circle, square, triangle, and diamond) represent the same patient within the different subpopulations. The box plot represents the median and interquartile range for healthy controls (n = 22). The antigens used to define subpopulations are depicted in Table E2. CM, Central memory; EM, effector memory.
Fig 4
Fig 4
Activation of lymphocyte subpopulations in the blood and BALF. A, Proportion of CD4 T-cell CD69 expression in the BALF (blue symbols) and blood (yellow symbols) of patients and healthy controls (blood only, gray circles), B) Proportion of CD8 T-cell CD69 expression in the BALF (blue symbols) and blood (yellow symbols) of patients and healthy controls (blood only, gray circles). C, Proportion of natural killer (NK) cell CD69 expression in BALF (blue symbols) and blood (yellow symbols) of patients and healthy controls (blood only, gray circles). Colored symbols (circle, square, triangle, and diamond) represent the same patient within the different subpopulations and within the 2 compartments (blue indicates BALF; yellow indicates blood). The box plot represents the median and interquartile range for healthy controls (n = 22).
Fig 5
Fig 5
Cytokines and chemokines measured in blood and BALF (log-transformed). The MSD V-Plex Human Biomarker Proinflammatory Panel 1, Cytokine Panels 1 and 2, and Chemokine Panel 1 were used for analyses of cytokines and chemokines. Data are depicted for the blood (A) and BALF (B) of both patients (yellow or blue circles) and healthy controls (gray circles [n = 15]). Cytokine data are also depicted on absolute scale in Fig E10. An internal positive control consisting of pooled plasma was used. A few cytokines were not detected in the blood (ie, IL-17F) and BALF (ie, IL-3, IL-9, IL-17D, and IL-17F). IP, IFN-γ–induced protein; MDC, macrophage-derived chemokine; TARC, thymus and activation-regulated chemokine; TSLP, thymic stromal lymphopoietin; VEGF, vascular endothelial growth factor.
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References

    1. World Health Organization Novel Coronavirus - China. https://www.who.int/csr/don/12-january-2020-novel-coronavirus-china/en/
    1. World Health Organization Coronavirus disease (COVID-19) pandemic. https://www.who.int/emergencies/diseases/novel-coronavirus-2019
    1. European Centre for Disease Prevention and Control COVID-19 situation update worldwide, as of 26 September 2020. https://www.ecdc.europa.eu/en/geographical-distribution-2019-ncov-cases
    1. Beigel JH, Tomashek KM, Dodd LE, Mehta AK, Zingman BS, Kalil AC, et al. Remdesivir for the treatment of Covid-19 - preliminary report [e-pub ahead of print]. N Engl J Med https://doi.org/10.1056/NEJMoa2007764. Accessed July 20, 2020. - DOI - PMC - PubMed
    1. Group RC, Horby P, Lim WS, Emberson JR, Mafham M, Bell JL, et al. Dexamethasone in hospitalized patients with Covid-19 - preliminary report. N Engl J Med. https://doi.org/10.1056/NEJMoa2021436. Accessed July 20, 2020. - DOI

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