CASP4/11 Contributes to NLRP3 Activation and COVID-19 Exacerbation.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection triggers activation of the NLRP3 inflammasome, which promotes inflammation and aggravates severe COVID-19. Here, we report that SARS-CoV-2 induces upregulation and activation of human caspase-4/CASP4 (mouse caspase-11/CASP11), and this process contributes to NLRP3 activation. In vivo infections performed in transgenic hACE2 humanized mice, deficient or sufficient for Casp11, indicate that hACE2 Casp11-/- mice were protected from disease development, with the increased pulmonary parenchymal area, reduced clinical score of the disease, and reduced mortality. Assessing human samples from fatal cases of COVID-19, we found that CASP4 was expressed in patient lungs and correlated with the expression of inflammasome components and inflammatory mediators, including CASP1, IL1B, IL18, and IL6. Collectively, our data establish that CASP4/11 promotes NLRP3 activation and disease pathology, revealing a possible target for therapeutic interventions for COVID-19.

Identification of immunomodulatory drugs that inhibit multiple inflammasomes and impair SARS-CoV-2 infection.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces mild or asymptomatic COVID-19 in most cases, but some patients develop an excessive inflammatory process that can be fatal. As the NLRP3 inflammasome and additional inflammasomes are implicated in disease aggravation, drug repositioning to target inflammasomes emerges as a strategy to treat COVID-19. Here, we performed a high-throughput screening using a 2560 small-molecule compound library and identified FDA-approved drugs that function as pan-inflammasome inhibitors. Our best hit, niclosamide (NIC), effectively inhibits both inflammasome activation and SARS-CoV-2 replication. Mechanistically, induction of autophagy by NIC partially accounts for inhibition of NLRP3 and AIM2 inflammasomes, but NIC-mediated inhibition of NAIP/NLRC4 inflammasome are autophagy independent. NIC potently inhibited inflammasome activation in human monocytes infected in vitro, in PBMCs from patients with COVID-19, and in vivo in a mouse model of SARS-CoV-2 infection. This study provides relevant information regarding the immunomodulatory functions of this promising drug for COVID-19 treatment.

Efferocytosis of SARS-CoV-2-infected dying cells impairs macrophage anti-inflammatory functions and clearance of apoptotic cells.

COVID-19 is a disease of dysfunctional immune responses, but the mechanisms triggering immunopathogenesis are not established. The functional plasticity of macrophages allows this cell type to promote pathogen elimination and inflammation or suppress inflammation and promote tissue remodeling and injury repair. During an infection, the clearance of dead and dying cells, a process named efferocytosis, can modulate the interplay between these contrasting functions. Here, we show that engulfment of SARS-CoV-2-infected apoptotic cells exacerbates inflammatory cytokine production, inhibits the expression of efferocytic receptors, and impairs continual efferocytosis by macrophages. We also provide evidence supporting that lung monocytes and macrophages from severe COVID-19 patients have compromised efferocytic capacity. Our findings reveal that dysfunctional efferocytosis of SARS-CoV-2-infected cell corpses suppresses macrophage anti-inflammation and efficient tissue repair programs and provides mechanistic insights for the excessive production of pro-inflammatory cytokines and accumulation of tissue damage associated with COVID-19 immunopathogenesis.

Buildout and integration of an automated high-throughput CLIA laboratory for SARS-CoV-2 testing on a large urban campus.

In 2019, the first cases of SARS-CoV-2 were detected in Wuhan, China, and by early 2020 the first cases were identified in the United States. SARS-CoV-2 infections increased in the US causing many states to implement stay-at-home orders and additional safety precautions to mitigate potential outbreaks. As policies changed throughout the pandemic and restrictions lifted, there was an increase in demand for COVID-19 testing which was costly, difficult to obtain, or had long turn-around times. Some academic institutions, including Boston University (BU), created an on-campus COVID-19 screening protocol as part of a plan for the safe return of students, faculty, and staff to campus with the option for in-person classes. At BU, we put together an automated high-throughput clinical testing laboratory with the capacity to run 45,000 individual tests weekly by Fall of 2020, with a purpose-built clinical testing laboratory, a multiplexed reverse transcription PCR (RT-qPCR) test, robotic instrumentation, and trained staff. There were many challenges including supply chain issues for personal protective equipment and testing materials in addition to equipment that were in high demand. The BU Clinical Testing Laboratory (CTL) was operational at the start of Fall 2020 and performed over 1 million SARS-CoV-2 PCR tests during the 2020-2021 academic year.

Depression, Anxiety and Stress in Health Professionals in the COVID-19 Context.

To assess the prevalence of depression, anxiety and stress symptoms in health professionals in the COVID-19 pandemic context. METHOD: Cross-sectional study with non-probabilistic (snow-ball) sampling method. The assessment was performed using the Depression, Anxiety, and Stress Scale (DASS-21) and the prevalence of symptoms severity was calculated by point and 95% confidence interval. The analysis of the psychometric properties of DASS-21 was performed using confirmatory factor analysis (CFA) and the following goodness of fit indices: χ2/df (chi-square ratio by degrees of freedom), Tucker-Lewis index (TLI), comparative fit index (CFI) and root mean square error of approximation (RMSEA) with a 90% confidence interval. RESULTS: The study participants were 529 health professionals (82.4% women and 66.7% nursing professionals). CFA of the DASS-21 structural model presented adequate fit for the sample (χ2/df = 3.530; CFI = 0.979; TLI = 0.976; RMSEA = 0.069). Regarding prevalence, moderate to extremely severe symptoms of depression, anxiety and stress were found in 48.6%, 55.0% and 47.9% of the participants, respectively. CONCLUSION: The use of DASS-21 confirmed the validity and reliability of the data. The prevalence of depression, anxiety and stress symptoms in the participants indicated a high risk of mental illness in health professionals in the COVID-19 pandemic.

Renal changes and acute kidney injury in covid-19: a systematic review.

OBJECTIVE: We aimed to present a review of renal changes in patients with COVID-19. METHODS: We performed a systematic review of the literature to identify original articles regarding clinical, laboratory, and anatomopathological kidney changes in patients infected with SARS-CoV-2 published until May 7, 2020. The search was carried out across PubMed, Scopus, and Embase using the keywords "COVID-19", "coronavirus", "SARS-CoV-2", "kidney injury" and "kidney disease". Fifteen studies presented clinical and laboratory renal changes in patients with COVID-19, and three addressed anatomopathological changes. DISCUSSION: Acute kidney injury (AKI) was a relevant finding in patients with COVID-19. There were also significant changes in laboratory tests that indicated kidney injury, such as increased serum creatinine and blood urea nitrogen (BUN), proteinuria, and hematuria. The presence of laboratory abnormalities and AKI were significant in severely ill patients. There was a considerable prevalence of AKI among groups of patients who died of COVID-19. Histopathological analysis of the kidney tissue of patients infected with SARS-CoV-2 suggested that the virus may directly affect the kidneys. CONCLUSION: Although COVID-19 affects mainly the lungs, it can also impact the kidneys. Increased serum creatinine and BUN, hematuria, proteinuria, and AKI were frequent findings in patients with severe COVID-19 and were related to an increased mortality rate. Further studies focusing on renal changes and their implications for the clinical condition of patients infected with the novel coronavirus are needed.

Renal changes and acute kidney injury in covid-19: a systematic review

SUMMARY OBJECTIVE We aimed to present a review of renal changes in patients with COVID-19. METHODS We performed a systematic review of the literature to identify original articles regarding clinical, laboratory, and anatomopathological kidney changes in patients infected with SARS-CoV-2 published until May 7, 2020. The search was carried out across PubMed, Scopus, and Embase using the keywords "COVID-19", "coronavirus", "SARS-CoV-2", "kidney injury"and "kidney disease". Fifteen studies presented clinical and laboratory renal changes in patients with COVID-19, and three addressed anatomopathological changes. DISCUSSION Acute kidney injury (AKI) was a relevant finding in patients with COVID-19. There were also significant changes in laboratory tests that indicated kidney injury, such as increased serum creatinine and blood urea nitrogen (BUN), proteinuria, and hematuria. The presence of laboratory abnormalities and AKI were significant in severely ill patients. There was a considerable prevalence of AKI among groups of patients who died of COVID-19. Histopathological analysis of the kidney tissue of patients infected with SARS-CoV-2 suggested that the virus may directly affect the kidneys. CONCLUSION Although COVID-19 affects mainly the lungs, it can also impact the kidneys. Increased serum creatinine and BUN, hematuria, proteinuria, and AKI were frequent findings in patients with severe COVID-19 and were related to an increased mortality rate. Further studies focusing on renal changes and their implications for the clinical condition of patients infected with the novel coronavirus are needed. RESUMO OBJETIVO Apresentar uma revisão sobre as alterações renais nos pacientes com COVID-19. MÉTODOS Foi realizada uma revisão sistemática de literatura para buscar estudos referentes a pacientes com alterações renais clínicas, laboratoriais e anatomopatológicas durante a infecção por SARS-CoV-2. A busca foi realizada nas bases de dados eletrônicos PubMed, Scopus e Embase, com as palavras-chaves: "COVID-19", "coronavirus", "Sars-CoV-2", "kidney injury"e "kidney disease", para identificar artigos originais publicados na literatura até 07 de maio de 2020. Quinze estudos trouxeram alterações renais clínicas e laboratoriais dos pacientes com COVID-19, e três abordaram análises anatomopatológicas. DISCUSSÃO A Lesão renal aguda (LRA) foi um achado relevante nos pacientes com COVID-19. Houve também alterações significativas nos exames laboratoriais que indicam lesão renal, como o nível de creatinina e ureia séricas, proteinúria e hematúria. As alterações laboratoriais e a LRA foram importantes nos pacientes que desenvolveram o quadro grave da doença. Há considerável prevalência de LRA nos grupos de pacientes que vieram a óbito. Na análise histopatológica de pacientes com SARS-CoV-2 foram encontrados achados renais sugestivos que o vírus poderia ter efeitos diretos sobre o rim. CONCLUSÃO A COVID-19 é uma doença que, apesar de acometer principalmente os pulmões, também acomete os rins. Aumento das escórias nitrogenadas, hematúria, proteinúria e LRA foram achados frequentes em pacientes com quadros graves da COVID-19. Esses achados foram relacionados a maior mortalidade. É necessária a realização de mais estudos com enfoque nas alterações renais e suas implicações no quadro clínico causadas pelo novo coronavírus.

Inflammasomes are activated in response to SARS-CoV-2 infection and are associated with COVID-19 severity in patients.

Severe cases of COVID-19 are characterized by a strong inflammatory process that may ultimately lead to organ failure and patient death. The NLRP3 inflammasome is a molecular platform that promotes inflammation via cleavage and activation of key inflammatory molecules including active caspase-1 (Casp1p20), IL-1ß, and IL-18. Although participation of the inflammasome in COVID-19 has been highly speculated, the inflammasome activation and participation in the outcome of the disease are unknown. Here we demonstrate that the NLRP3 inflammasome is activated in response to SARS-CoV-2 infection and is active in COVID-19 patients. Studying moderate and severe COVID-19 patients, we found active NLRP3 inflammasome in PBMCs and tissues of postmortem patients upon autopsy. Inflammasome-derived products such as Casp1p20 and IL-18 in the sera correlated with the markers of COVID-19 severity, including IL-6 and LDH. Moreover, higher levels of IL-18 and Casp1p20 are associated with disease severity and poor clinical outcome. Our results suggest that inflammasomes participate in the pathophysiology of the disease, indicating that these platforms might be a marker of disease severity and a potential therapeutic target for COVID-19.