Emerging roles of SARS-CoV-2 Spike-ACE2 in immune evasion and pathogenesis

Significance • The recent finding that the SARS-CoV-2 spike protein exploits ACE2 signaling to suppress immunological synapse assembly and CD8+ cytotoxic T lymphocyte-mediated killing highlights a potential role for the spike-ACE2 axis in the extrapulmonary manifestations of COVID-19. The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has caused an estimated 5 billion infections and 20 million deaths by respiratory failure. In addition to the respiratory disease, SARS-CoV-2 infection has been associated with many extrapulmonary complications not easily explainable by the respiratory infection. A recent study showed that the SARS-CoV-2 spike protein, which mediates cell entry by binding to the ACE2 receptor, signals through ACE2 to change host cell behavior. In CD8+ T cells, Spike-dependent ACE2-mediated signaling suppresses immunological synapse formation and impairs their killing ability, leading to immune escape of virus-infected cells. In this opinion article, we discuss the consequences of ACE2 signaling on the immune response and propose that it contributes to the extrapulmonary manifestations of COVID-19.

Effect of the COVID-19 Lockdown on Domestic Water Consumption by Smart Water Network Data Filtering

The COVID-19 pandemic and the consequent containment policies have changed people's habits, with numerous implications in all fields. The restrictions also had consequences on drinking water consumption. This work analyzes this influence in the Soccavo district of Naples (Campania), in Italy, during the two periods of the strongest restrictions: the national lockdown (11 March–3 May) and the autumn red zone (16 November–6 December) in 2020. Thanks to a smart water grid acquisition system, the analysis of a large amount of data measured in the years 2019 (considered the average reference year) and 2020 was carried out. Data of the same meters in the two consecutive years were preliminarily filtered by identification and elimination of anomalies and outliers, as well as of anomalous annual patterns, through clustering and classification. The comparison was performed for the two years considering the daily and weekly average hourly patterns;the average daily patterns of midweek days, Saturdays, and Sundays, respectively;and the total daily volumes. The results showed a general increase in residential water consumption and a modification in usage patterns as a consequence of the COVID-19 pandemic containment measures.

SARS-CoV-2 and Skin: The Pathologist's Point of View.

The SARS-CoV-2 pandemic has dramatically changed our lives and habits. In just a few months, the most advanced and efficient health systems in the world have been overwhelmed by an infectious disease that has caused 3.26 million deaths and more than 156 million cases worldwide. Although the lung is the most frequently affected organ, the skin has also resulted in being a target body district, so much so as to suggest it may be a real "sentinel" of COVID-19 disease. Here we present 17 cases of skin manifestations studied and analyzed in recent months in our Department; immunohistochemical investigations were carried out on samples for the S1 spike-protein of SARS-CoV-2, as well as electron microscopy investigations showing evidence of virions within the constituent cells of the eccrine sweat glands and the endothelium of small blood vessels. Finally, we conduct a brief review of the COVID-related skin manifestations, confirmed by immunohistochemistry and/or electron microscopy, described in the literature.

Vaccinology in the post-COVID-19 era.

The COVID-19 pandemic is a shocking reminder of how our world would look in the absence of vaccination. Fortunately, new technologies, the pace of understanding new and existing pathogens, and the increased knowledge of the immune system allow us today to develop vaccines at an unprecedented speed. Some of the vaccine technologies that are fast-tracked by the urgency of COVID-19 may also be the answer for other health priorities, such as antimicrobial resistance, chronic infections, and cancer, that the post-COVID-19 world will urgently need to face. This perspective analyzes the way COVID-19 is transforming vaccinology and the opportunities for vaccines to have an increasingly important role in health and well-being.