Preliminary report of in vitro and in vivo effectiveness of dornase alfa on SARS-CoV-2 infection

Dornase alfa, the recombinant form of the human DNase I enzyme, breaks down neutrophil extracellular traps (NET) that include a vast amount of DNA fragments, histones, microbicidal proteins and oxidant enzymes released from necrotic neutrophils in the highly viscous mucus of cystic fibrosis patients. Dornase alfa has been used for decades in patients with cystic fibrosis to reduce the viscoelasticity of respiratory tract secretions, to decrease the severity of respiratory tract infections, and to improve lung function. Previous studies have linked abnormal NET formations to lung diseases, especially to acute respiratory distress syndrome (ARDS). It is well known that novel coronavirus disease 2019 (COVID-19) pneumonia progresses to ARDS and even multiple organ failure. High blood neutrophil levels are an early indicator of COVID-19 and predict severe respiratory diseases. Also it is reported that mucus structure in COVID-19 is very similar to that in cystic fibrosis due to the accumulation of excessive NET in the lungs. In this study, we showed the recovery of three individuals with COVID-19 after including dornase alfa in their treatment. We followed clinical improvement in the radiological analysis (two of three cases), oxygen saturation (Spo₂), respiratory rate, disappearance of dyspnoea, coughing and a decrease in NET formation and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load after the treatment. Also here, we share our preliminary results suggesting that dornase alfa has an anti-viral effect against SARS-CoV-2 infection in a green monkey kidney cell line, Vero, and a bovine kidney cell line, MDBK, without determined cytotoxicity on healthy peripheral blood mononuclear cells.

The influence of cisplatin, doxorubicin, pegylated doxorubicin, oxaliplatin and gemcitabine on mahlavu cell line

PURPOSE

Hepatocellar carcinoma (HCC) remains a major health problem being the third leading cause of deaths due to cancer worldwide. Because HCC is known to be highly resistant to conventional systemic therapies, single-agent or combination of systemic therapies have been investigated. Today, sorafenib, a multikinase inhibitor, is the only approved systemic agent for the first line treatment of advanced HCC. In this study, we aimed to investigate the influence of different concentrations of cisplatin, doxorubicin, pegylated doxorubicin (PLD), oxaliplatin and gemcitabine by applying these agents either single or in combinations on mahlavu cell line.

METHODS

HCC mahlavu cell line was used for the experiments. Cell death was measured by flow cytometry at 48 hrs after incubation with various concentrations (0.1 μg/ml, 1.0 μg/ml and 10 μg/ml) of the drugs.

RESULTS

Cell death due to gemcitabine was found to be significantly higher than cell deaths caused by the other single agents including cisplatin, oxaliplatin, doxorubicin and PLD (p<0.001, p<0.001, p<0.001 and p=0.0049, respectively). There was no significant difference between gemcitabine and both the gemcitabine combination with doxorubicin and PLD (p=0.992 and p=0.441, respectively).

CONCLUSION

This is a preliminary analysis evaluating the effect of the conventional chemotherapeutic agents on mahlavu cell line in vitro. The findings of this study suggest that gemcitabine-based therapies keep on being the prefered therapeutic approach for the treatment of HCC.