Identifying and testing cancer-derived synthetic-lethal anti-SARS-CoV-2 targets

Introduction: Despite the development of two mRNA vaccines, there is an urgent unmet need of finding new antiviral strategies. One such potential antiviral strategy is to target the synthetic lethal (SL) partners of transcriptionally altered genes in infected host cells, thereby selectively killing them to halt the infection at its heels (Mast FD, JCB, 2020). Methods: Here we conduct a first proof-of-concept SL inference approach to predict anti-SARS-CoV-2 targets in a systematic genome-wide manner. This effort capitalizes on our recently published pipeline for inferring clinically relevant SL interactions in cancer (Lee et al, Cell, 2021). Based on the latter, we comprehensively analyzed multiple in vitro and in vivo bulk and single-cell RNA-sequencing datasets of SARS-CoV-2 infection to predict candidate antiviral targets that are SL with altered host genes. Importantly, as our predictions are fine-tuned based on the analysis of patients' data, they are more likely to be of translational value. Results: Our key results are twofold:1) The predicted SL-based targets are highly enriched for genes that are reported in four SARS-CoV-2 CRISPR-Cas9 genome-wide genetic screens to inhibit growth of infected cells. 2) A subset of top predicted 26 genes were experimentally tested in a targeted siRNA screen conducted in both infected and non-infected human Caco-2 cells. Remarkably, as expected given that these targets were predicted to be SL specific with genes upregulated in infected cells, indeed, knocking down these targets reduced viral replication and cell viability only under the infected condition without harming non-infected cells. Conclusion: In summary, this study is the first to demonstrate the potential of a synthetic lethality approach to identify viral (specifically anti-SARS-CoV-2) targets. Importantly, as both single cell and bulk transcriptomics patients' data is considered from both infected people and controls, they are more likely to be of clinical relevance. Targeting host genes identified via an SL-based approach is probably more suitable when the infection is at the early stage and host can still tolerate the loss of infected host cells.

Post-COVID-19 Lung Transplantation Italian Pivotal Protocol: Some Ethical Considerations.

SARS­CoV­2 mostly affects the respiratory system with clinical patterns ranging from the common cold to fatal pneumonia. During the first wave of the COVID-19 pandemic, owing to the high number of patients who were infected with SARS­CoV­2 and subsequently recovered, it has been shown that some patients with post-COVID-19 terminal respiratory failure need lung transplantation for survival. There is increasing evidence coming from worldwide observations that this procedure can be performed successfully in post-COVID-19 patients. However, owing to the scarcity of organs, there is a need to define the safety and efficacy of lung transplant for post-COVID-19 patients as compared to patients waiting for a lung transplant for other pre-existing conditions, in order to ensure that sound ethical criteria are applied in organ allocation. The Milan's Policlinic Lung Transplant Surgery Unit, with the revision of the National Second Opinion for Infectious Diseases and the contribution of the Italian Lung Transplant Centres and the Italian National Transplant Centre, set up a pivotal observational protocol for the lung transplant of patients infected and successively turned negative for SARS­CoV­2, albeit with lung consequences such as acute respiratory distress syndrome or some chronic interstitial lung disease. The protocol was revised and approved by the Italian National Institute of Health Ethics Committee. Description of the protocol and some ethical considerations are reported in this article.

Protection of individual and collective health: ethical-legal issues and opportunities for public health after COVID-19

The Istituto Superiore di Sanita (the National Institute of Health in Italy), as the technical-scientific body of the Italian National Health Service, has a crucial role in the COVID-19 pandemic management in Italy. In this period the ISS Bioethics COVID-19 Working Group has been established to deal with the multiple ethical issues raised by the pandemic. The spread of SARS-CoV-2 has made it necessary to address both clinical ethics questions and public health ethics dilemmas. In the Working Group experts in multiple disciplines - i.e., clinical medicine, public health, epidemiology, paediatrics, palliative care, law, philosophy, biomedical research, nursing sciences and, of course, bioethics - have been debating. This volume contains different Working Group members' contributions and viewpoints, that reflect the multiplicity of disciplines and experiences in an epochal emergency.