Characterization and treatment of SARS-CoV-2 in nasal and bronchial human airway epithelia

Andrés Pizzorno; Blandine Padey; Thomas Julien; Sophie Trouillet-Assant; Aurélien Traversier; Elisabeth Errazuriz-Cerda; Julien Fouret; Julia Dubois; Alexandre Gaymard; François-Xavier Lescure; Victoria Dulière; Pauline Brun; Samuel Constant; Julien Poissy; Bruno Lina; Yazdan Yazdanpanah; Olivier Terrier; Manuel Rosa-Calatrava

Taken together, our results highlight distinctive transcriptional immune signatures between nasal 155 and bronchial HAE, both in terms of kinetics and intensity, hence suggesting potential intrinsic differences in the early response to SARS-CoV-2 infection between the upper and lower respiratory tract. These results are in accordance with the first clinical reports describing in some patients a rapid worsening of the respiratory condition and overall clinical state by day 7-10 after symptom onset (21) , most probably related to a cytokine storm syndrome (22). We therefore evaluated in both VeroE6 and HAE model the antiviral potential against SARS-CoV-2 of remdesivir monotherapy but also in combination with diltiazem. Diltiazem is a voltage gated 170 Ca2+ channel antagonist currently used as anti-hypertensive for the control of angina pectoris and cardiac arrhythmia (26) , which we have recently repurposed as an effective host-directed influenza inhibitor due to its so far undescribed capacity of inducing the interferon (IFN) antiviral response, particularly type III IFNs (Fig. S2) (8) . Additionally, the rationale of testing such virus-directed plus host-directed drug combination is consistent with a novel study describing hypertension as a 175 potential risk factor observed among a cohort of inpatients with COVID-19 (19), and two reports not anticipating potential adverse effects of diltiazem (27) or negative pharmacological interactions of between remdesivir and diltiazem for the treatment of COVID-19 (28) . The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.03.31.017889 doi: bioRxiv preprint diltiazem monotherapy in our experimental conditions. Nonetheless, addition of 11.5 µM diltiazem significantly potentiated the antiviral effect of remdesivir ( Fig. 4A-C) , inducing 68% and 50% 185 reductions in remdesivir IC50 values at 48 and 72 hpi, respectively. Comparably, daily treatment with 20 µM remdesivir resulted in 7.3 log10 and 7.9 log10 reductions of intracellular SARS-CoV-2 viral titers at 48 hpi in nasal and bronchial HAE, respectively (Fig. 4D, upper panel) . Not surprisingly for a model with a completely functional IFN response, daily treatment with 90 µM diltiazem resulted in moderate yet substantial (0.4 log10 and 0.8 log10, respectively) reductions of 190 intracellular viral titers in nasal and bronchial HAE at the same time-point (Fig. 4D, upper panel) .