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. 2022 Sep 30:13:1012027.
doi: 10.3389/fimmu.2022.1012027. eCollection 2022.

Dysfunctional purinergic signaling correlates with disease severity in COVID-19 patients

Anna Julia Pietrobon  1   2 , Roberta Andrejew  3 , Ricardo Wesley Alberca Custódio  1 , Luana de Mendonça Oliveira  1   2 , Juliete Nathali Scholl  4 , Franciane Mouradian Emidio Teixeira  1   2 , Cyro Alves de Brito  5 , Talita Glaser  3 , Julia Kazmierski  6   7 , Christine Goffinet  6   7 , Anna Claudia Turdo  8 , Tatiana Yendo  1 , Valeria Aoki  1 , Fabricio Figueiró  4 , Ana Maria Battastini  4 , Henning Ulrich  3 , Gill Benard  1 , Alberto Jose da Silva Duarte  1 , Maria Notomi Sato  1
Affiliations

Dysfunctional purinergic signaling correlates with disease severity in COVID-19 patients

Anna Julia Pietrobon et al. Front Immunol. .

Abstract

Ectonucleotidases modulate inflammatory responses by balancing extracellular ATP and adenosine (ADO) and might be involved in COVID-19 immunopathogenesis. Here, we explored the contribution of extracellular nucleotide metabolism to COVID-19 severity in mild and severe cases of the disease. We verified that the gene expression of ectonucleotidases is reduced in the whole blood of patients with COVID-19 and is negatively correlated to levels of CRP, an inflammatory marker of disease severity. In line with these findings, COVID-19 patients present higher ATP levels in plasma and reduced levels of ADO when compared to healthy controls. Cell type-specific analysis revealed higher frequencies of CD39+ T cells in severely ill patients, while CD4+ and CD8+ expressing CD73 are reduced in this same group. The frequency of B cells CD39+CD73+ is also decreased during acute COVID-19. Interestingly, B cells from COVID-19 patients showed a reduced capacity to hydrolyze ATP into ADP and ADO. Furthermore, impaired expression of ADO receptors and a compromised activation of its signaling pathway is observed in COVID-19 patients. The presence of ADO in vitro, however, suppressed inflammatory responses triggered in patients' cells. In summary, our findings support the idea that alterations in the metabolism of extracellular purines contribute to immune dysregulation during COVID-19, possibly favoring disease severity, and suggest that ADO may be a therapeutic approach for the disease.

Keywords: ATP; CD39; CD73; COVID-19; SARS-CoV-2; adenosine; purinergic signaling.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Altered expression of nucleotidases and purinergic composition in the blood of COVID-19 patients. (A) Gene expression of nucleotidases ENPP1, ENPP2, ENPP3, ENTPD5, ENTPD1 (CD39) and NT5E (CD73) in whole blood of healthy donors (n=8) and COVID-19 patients (Mild hospitalized, n=10; Severe, n=10). (B) Negative correlation between the expression of nucleotidases and blood levels of C-reactive protein (CRP) in COVID-19 patients. (C) Plasma levels of ATP and ADO in healthy donors (n=14) and COVID-19 patients (Mild hospitalized, n=23; Severe, n=21). Data are shown as the median. One-way ANOVA test: *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001. Spearman’s correlation test was used to determine the correlation coefficient (r) and the significance (p<0.05). Blue dots indicate healthy donors (HD) whereas orange and red dots indicate hospitalized patients with mild and severe (Sev) COVID-19, respectively.
Figure 2
Figure 2
Altered frequency of CD39+ and CD73+ leucocytes in the blood of COVID-19 patients. Frequency and expression of CD39 and CD73 in (A) CD4+ T cells, (B) CD8+ T cells and (C) CD19+ cells from healthy donors (n=14) and COVID-19 patients (Mild hospitalized, n=14-21; Severe, n=12-24) based on the percentage of positive cells and the median of fluorescence (MFI) values. (D) Concentration of plasmatic CD73 from healthy donors (n=13) and COVID-19 patients (Mild hospitalized, n=25; Severe, n=24). (E) Heatmap of average gene expression values for ENPP1, ENPP2, ENPP3, ENTPD1, and NT5E in B cells, CD4+ T cells, and CD8+ T cells exposed or not to SARS-CoV-2. One-way ANOVA test: *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001. Blue dots indicate healthy donors (HD) whereas orange and red dots indicate hospitalized patients with mild and severe (Sev) COVID-19, respectively.
Figure 3
Figure 3
Decreased hydrolysis of ATP by COVID-19 patients’ B cells. Isolated B cells from healthy donors (n=7) and COVID-19 patients (Severe, n=6) were incubated with 500 μM of ATP for 15, 30, and 60 minutes. Consumption of ATP (A) and production of ADP (B), AMP (C), and ADO (D) was accessed. Data shown as mean with SD. Two-way ANOVA with Bonferroni’s post-test for multiple comparisons: *p<0.05, **p<0.01, ***p<0.001. Blue lines indicate healthy donors (HD) whereas red lines indicate patients with severe (Sev) COVID-19.
Figure 4
Figure 4
Impaired ADO signaling in COVID-19 patients. (A) Gene expression of ADORA1, ADORA2A, ADORA2B, and ADORA3 in whole blood of healthy donors (n=11) and COVID-19 patients (Mild hospitalized, n=10; Severe, n=13). Data presented as median. One-way ANOVA test: *p<0.05. (B) Heatmap of A1R, A2AR, A2BR, and A3R MFI values expression in lymphocytes and granulocytes of healthy donors (n=6) and COVID-19 patients (Mild hospitalized, n=4; Severe, n=8) based on the median of fluorescence (MFI) values. Data presented as mean. One-way ANOVA test: *p<0.05, **p<0.01. (C) MNCs from healthy donors (n=4) and COVID-19 patients (n=4) were incubated with ATP (100 μM) or ADO (100 μM) for 30 minutes. The PKA activity is shown. Data presented as median. Mann-Whitney U test: *p<0.05 (HD vs. COVID-19). Blue dots indicate healthy donors (HD) whereas orange and red dots indicate hospitalized patients with mild and severe (Sev) COVID-19, respectively.
Figure 5
Figure 5
ADO prevents cellular activation triggered by TLRs and induces anti-inflammatory responses. (A) MNCs from healthy donors (n=8) and COVID-19 patients (n=11) were incubated with ADO (100 μM) for 2 hours followed by activation with TLR7/8 agonist. Cytokine production in the supernatant after 24h is shown. (B) MNCs from healthy donors (n=8) and COVID-19 patients (n=7) were incubated with ADO (100 μM) for 24 hours and IL-10 production in the supernatant after 24h was accessed. Data are shown as the median. Wilcoxon signed-rank test: #p<0.05; ##p<0.01, ###p<0.001 (between different treatments). Mann-Whitney U test: *p<0.05 (HD vs. COVID-19). Blue dots indicate healthy donors (HD) whereas red dots indicate patients with COVID-19.
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References

    1. Merad M, Martin JC. Pathological inflammation in patients with COVID-19: a key role for monocytes and macrophages. Nat Rev Immunol (2020) 20(6):355–62. doi: 10.1038/s41577-020-0331-4 - DOI - PMC - PubMed
    1. Lai CC, Ko WC, Lee PI, Jean SS, Hsueh PR. Extra-respiratory manifestations of COVID-19. Int J Antimicrob Agents (2020) 56(2):106024. doi: 10.1016/j.ijantimicag.2020.106024 - DOI - PMC - PubMed
    1. Chen G, Wu D, Guo W, Cao Y, Huang D, Wang H, et al. . Clinical and immunological features of severe and moderate coronavirus disease 2019. J Clin Invest (2020) 130(5):2620–9. doi: 10.1172/JCI137244 - DOI - PMC - PubMed
    1. Puelles VG, Lütgehetmann M, Lindenmeyer MT, Sperhake JP, Wong MN, Allweiss L, et al. . Multiorgan and renal tropism of SARS-CoV-2. N Engl J Med (2020) 383(6):590–2. doi: 10.1056/NEJMc2011400 - DOI - PMC - PubMed
    1. Darby M, Kuzmiski JB, Panenka W, Feighan D, MacVicar BA. ATP released from astrocytes during swelling activates chloride channels. J Neurophysiol (2003) 89(4):1870–7. doi: 10.1152/jn.00510.2002 - DOI - PubMed

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