The Dysregulation of the Monocyte-Dendritic Cell Interplay Is Associated with In-Hospital Mortality in COVID-19 Pneumonia (preprint)

Background: The monocyte-phagocyte system (MPS), including monocytes/macrophages and dendritic cells (DCs), plays a key role in anti-viral immunity. We aimed to analyze the prognostic value of the MPS components on in-hospital mortality in a cohort of 58 patients (M/F ; mean ageSD years) with COVID-19 pneumonia and 22 age- and sex-matched healthy controls. Methods: We measured frequencies and absolute numbers of peripheral blood CD169+ monocytes, conventional CD1c+ and CD141+ (namely cDC2 and cDC1), and plasmacytoid CD303+ DCs by means of multi-parametric flow cytometry. A gene profile analysis of 770 immune-inflammatory related human genes and 20 SARS-CoV-2 genes was also performed. Results: Median frequencies and absolute counts of CD169-expressing monocytes were significantly higher in COVID-19 patients than in controls (p 0.04 and p 0.01, respectively). Conversely, percentages and absolute numbers of all DC subsets were markedly depleted in patients (p

Cytokine Signature and COVID-19 Prediction Models in the Two Waves of Pandemics. (preprint)

In Europe, two waves of infections with SARS-CoV-2 (COVID-19) have been observed to date. Here, we have investigated whether common patterns of cytokines could be detected in individuals with mild and severe forms of COVID-19 in the two pandemic waves, and whether machine learning approach could be useful to identify the best predictors. An increasing trend of multiple cytokines was observed in patients with mild or severe/critical symptoms of COVID-19, compared with healthy volunteers. Linear Discriminant Analysis (LDA) clearly recognized the three groups based on cytokine patterns. Classification and Regression Tree (CART) further indicated that IL-6 discriminated controls and COVID-19 patients, whilst IL-8 defined disease severity. During the second wave of pandemics, a less intense cytokine storm was observed. CART analysis revealed that IL-6 was the most robust predictor of infection and discriminated moderate COVID-19 patients from healthy controls, regardless of epidemic peak curve. Thus, serum cytokine patterns provide non-invasive biomarkers useful for COVID-19 diagnosis and prognosis. Further definition of individual cytokines may allow to envision novel therapeutic options and pave the way to set up innovative diagnostic tools.

Long-chain polyphosphates impair SARS-CoV-2 infection and replication: a route for therapy in man (preprint)

Anti-viral activities of long-chain inorganic polyphosphates (PolyPs) against severe acute respiratory syndrome coronavirus (SARS-CoV)-2 infection were investigated. In molecular docking analyses, PolyPs interacted with several conserved angiotensin-converting enzyme (ACE)2 and RNA-dependent RNA polymerase (RdRp) amino acids. We thus tested PolyPs for functional interactions in vitro in SARS-CoV-2-infected Vero E6, Caco2 and human primary nasal epithelial cells. Immunofluorescence, qPCR, direct RNA sequencing, FISH and Immunoblotting were used to determine virus loads and transcription levels of genomic(g)RNAs and sub-genomic(sg)RNAs. We show that PolyP120 binds to ACE2 and enhances its proteasomal degradation. PolyP120 shows steric hindrance of the genomic Sars-CoV-2-RNA/RdRP complex, to impair synthesis of positive-sense gRNAs, viral subgenomic transcripts and structural proteins needed for viral replication. Thus, PolyP120 impairs infection and replication of Korean and European (containing non-synonymous variants) SARS-CoV-2 strains. As PolyPs have no toxic activities, we envision their use as a nebulised formula for oropharyngeal delivery to prevent infections of SARS-CoV-2 and during early phases of antiviral therapy.

Evaluation of the diagnostic accuracy of a new point-of-care rapid test for SARS-CoV-2 virus detection (preprint)

Background: The easy access to a quick diagnosis of coronavirus disease 2019 (COVID-19) is a key point to improve the management of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and to contain its spread. Up to now, laboratory real-time PCR is the standard of care, but requires a fully equipped laboratory and significant infrastructure. Consequently, new diagnostic tools are required. Methods: In the present work, the diagnostic accuracy of the point-of-care rapid test "bKIT Virus Finder COVID-19" (Hyris Ltd) is evaluated by a retrospective and a prospective analysis on SARS CoV-2 samples previously assessed with an FDA “authorized for the emergency use - EUA” reference method. Descriptive statistics were used for the present study.Results: Results obtained with the Hyris Kit are the same as that of standard laboratory-based real time PCR methods for all the analyzed samples. In addition, the Hyris Kit provides the test results in less than 2 hours, a significantly shorter time compared to the reference methods, without the need of a fully equipped laboratory. Conclusions: To conclude, the Hyris kit represents a promising tool to improve the health surveillance and to increase the capacity of SARS-CoV-2 testing.

Tocilizumab for patients with COVID-19 pneumonia. The TOCIVID-19 phase 2 trial (preprint)

BackgroundTocilizumab blocks pro-inflammatory activity of interleukin-6 (IL-6), involved in pathogenesis of pneumonia the most frequent cause of death in COVID-19 patients. MethodsA multicentre, single-arm, hypothesis-driven phase 2 trial was planned to study the effect of Tocilizumab on lethality rates at 14 and 30 days (co-primary endpoints). A cohort of patients consecutively enrolled after phase 2 was used as a validation dataset. A multivariable logistic regression was performed to generate hypotheses, while controlling for possible confounders. Resultsout of 301 patients in phase 2 intention-to-treat (ITT) analysis, 180 (59.8%) received tocilizumab. With 67 death events, lethality rates were 18.4% (97.5%CI: 13.6-24.0, P=0.52) and 22.4% (97.5%CI: 17.2-28.3, P<0.001) at 14 and 30 days. Lethality rates were lower in the validation dataset, including 920 patients. No signal of specific drug toxicity was reported. The multivariable logistic regression suggests tocilizumab might be more effective in patients not requiring mechanical respiratory support at baseline. Also, it supports a positive effect on lethality rate of the use of corticosteroids. ConclusionsTocilizumab reduced lethality rate at 30 days compared with null hypothesis, without significant toxicity. Such result support the use of tocilizumab while waiting for ongoing phase 3 trials. RegistrationEudraCT (2020-001110-38); clinicaltrials.gov (NCT04317092)