Project description:Single-cell RNA-seq of iPSC derived human kidney organoids. Single-nuclei RNA-seq data of COVID-19 patient autopsy kidney tissue. The current data was used to suggest that SARS-CoV-2 can directly infect kidney cells and induce cell injury as well as a pro-fibrotic environment which could explain acute kidney injury in COVID-19 patients and also long-term effects potentially leading to the development of chronic kidney disease.
Project description:Extrapulmonary manifestations of COVID-19 have gained attention, not only due to their links to clinical outcomes, but also due to their potential long-term sequelae1. Recent evidence has shown multi-organ tropism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including heart, kidney and liver2. Previous studies have shown that close to 20% of hospitalized patients with COVID-19 develop liver injury, showing an association to disease severity3. Here, we identified a high frequency of liver enzyme alterations at admission in COVID-19 patients who required hospitalization. Then, we characterized SARS-CoV-2 liver tropism in autopsy samples, based on the expression of cell-entry facilitators in parenchymal cells, clinical polymerase chain reaction (PCR) positivity, subgenomic SARS-CoV-2 identification using RNA sequencing, and viral RNA detection by in situ hybridization. Next, we unraveled the transcriptomic and proteomic landscape of SARS-CoV-2 liver tropism, revealing significant increases in interferon alpha and gamma signaling and compensatory liver-specific metabolic regulation. While these results reflect changes in tissues from patients with severe SARS-CoV-2 infection, these profound molecular alterations raise questions about the potential long-term consequences of COVID-19 infection.
Project description:SARS-CoV-2 infections initiate cytokine storms and activate genetic programs leading to progressive hyperinflammation in multiple organs of patients with COVID-19. While it is known that COVID-19 impacts kidney function, leading to increased mortality, cytokine response of renal epithelium has not been studied in detail. Here, we report on the genetic programs activated in human primary proximal tubule (HPPT) cells by interferons and their suppression by ruxolitinib, a Janus kinase (JAK) inhibitor used in COVID-19 treatment. Integration of our data with those from patients with acute kidney injury and COVID-19, as well as other tissues, permitted the identification of kidney-specific interferon responses. Additionally, we investigated the regulation of the recently discovered isoform (dACE2) of the angiotensin-converting enzyme 2 (ACE2), the SARS-CoV-2 receptor. Using ChIP-seq, we identified candidate interferon-activated enhancers controlling the ACE2 locus, including the intronic dACE2 promoter. Taken together, our study provides an in-depth understanding of genetic programs activated in kidney cells.
Project description:COVID-19 induces profound B-cell dysregulation, notably a marked expansion of plasmablasts (PB), whose functional role remains unclear. This study aimed to characterize PB dynamics and functions in COVID-19 and their association with disease severity. We performed longitudinal immune profiling in a prospective cohort of 50 patients with COVID-19 (cohort 1), including flow cytometry-based B-cell immunophenotyping and multiplex cytokine analysis at days 1, 7, 14, and 30. A second retrospective cohort of 282 corticosteroid-naïve patients (cohort 2) was used to validate PB dynamics, model PB trajectories, and perform transcriptomic profiling of sorted PB. PB expansion occurred early in COVID-19 and was positively correlated with maximal disease severity (r=0.53, p<0.0001). Two distinct PB expansion trajectories were identified: one rapidly resolving, and one persistent and amplified, the latter being associated with higher severity scores and 30-day mortality (31% vs. 5%, p<0.001). In cohort 1, BAFF levels at day 7 correlated positively with both PB proportion (r=0.59, p=0.002) and maximal disease severity (r=0.74, p<0.001). Transcriptomic profiling of PB in cohort 2 revealed severity-specific signatures: in severe cases, early PB upregulated genes related to purine metabolism and CD39 expression, suggesting a pro-inflammatory role. In non-severe cases, PB expressed interferon-related and CIITA-mediated MHC-II programs, indicative of antiviral function. PB display dual functional profiles in COVID-19, acting either as regulators of antiviral immunity or as amplifiers of inflammation in severe disease. These findings support exploring therapeutic strategies targeting the BAFF-PB axis in severe COVID-19.
Project description:The objective of the study was to characterize the immunoreactivity profiles of IgG-reactive epitopes in COVID-19 patients with distinct disease trajectories as well as SARS-CoV-2-naïve sera, using a high-density SARS-CoV-2 whole proteome peptide microarray. The microarray comprised of a total of 5347 individual peptides, each consisting of 15 amino acids with an overlap of 13 amino acids printed in duplicate. The microarray also had a panel of the most relevant mutations from SARS-CoV-2 variants of concern like omicron, alpha, beta, gamma, delta, and others. This study consisted of 29 participants, including 10 naïve controls (5 pre-pandemic and 5 SARS-CoV-2 seronegative) and 19 RT-PCR-confirmed COVID-19 patients. The COVID-19 patients were stratified into two distinct cohorts based on their disease trajectories: the severe cohort (S), in which the patients presented moderate COVID-19 symptoms initially but eventually progressed toward severity; and the recovered cohort (R), in which severe COVID-19 patients progressed toward recovery. Our findings contribute to a deeper understanding of the immunopathogenesis of COVID-19 in patients with different disease trajectories, the effect of mutations on immunoreactivity, and potential cross-reactivity due to exposure to common cold viruses.
Project description:In children and younger adults up to 39 years of age, SARS-CoV-2 usually elicits mild symptoms that resemble the common cold. Disease severity increases with age starting at 30 and reaches astounding mortality rates that are ~330 fold higher in persons above 85 years of age compared to those 18-39 years old. To understand age-specific immune pathobiology of COVID-19 we have analyzed soluble mediators, cellular phenotypes, and transcriptome from over 80 COVID-19 patients of varying ages and disease severity, carefully controlling for age as a variable. We found that reticulocyte numbers and peripheral blood transcriptional signatures robustly correlated with disease severity. By contrast, decreased numbers and proportion of naïve T cells, reported previously as a COVID-19 severity risk factor, were found to be general features of aging and not of COVID-19 severity, as they readily occurred in older participants experiencing only mild or no disease at all. Single-cell transcriptional signatures across age and severity groups showed that severe but not moderate/mild COVID-19 causes cell stress response in different T cell populations, and some of that stress was unique to old severe participants, suggesting that in severe disease of older adults, these defenders of the organism may be disabled from performing immune protection. These findings shed new light on interactions between age and disease severity in COVID-19.
Project description:Impaired immunometabolic response in the elderly regulates inflammation-driven COVID-19 severity which confers the greatest risk of mortality. To investigate how aging compromises defense against COVID-19, we developed a model of natural murine beta coronavirus (mCoV) infection with mouse hepatitis virus strain A59 (mCoV-A59) that recapitulated majority of hallmarks of COVID-19. Aged mCoV-A59-infected mice have increased mortality and higher systemic inflammation in the heart, adipose tissue and hypothalamus, including neutrophilia and loss of γδ T cells in lungs. Ketogenic diet increases beta-hydroxybutyrate, expands tissue protective γδ T cells, deactivates the inflammasome and decreases pathogenic monocytes in lungs during aging. These data underscore the value of mCoV-A59 model to test mechanism and establishes harnessing of ketogenic immunometabolic checkpoint as potential treatment against COVID-19 in the elderly.
Project description:Impaired immunometabolic response in the elderly regulates inflammation-driven COVID-19 severity which confers the greatest risk of mortality. To investigate how aging compromises defense against COVID-19, we developed a model of natural murine beta coronavirus (mCoV) infection with mouse hepatitis virus strain A59 (mCoV-A59) that recapitulated majority of hallmarks of COVID-19. Aged mCoV-A59-infected mice have increased mortality and higher systemic inflammation in the heart, adipose tissue and hypothalamus, including neutrophilia and loss of γδ T cells in lungs. Ketogenic diet increases beta-hydroxybutyrate, expands tissue protective γδ T cells, deactivates the inflammasome and decreases pathogenic monocytes in lungs during aging. These data underscore the value of mCoV-A59 model to test mechanism and establishes harnessing of ketogenic immunometabolic checkpoint as potential treatment against COVID-19 in the elderly.
Project description:Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and resulting coronavirus disease (COVID-19) causes placental dysfunction, which increases the risk of adverse pregnancy outcomes. While abnormal placental pathology resulting from COVID-19 is common, direct infection of the placenta is rare. This suggests that pathophysiology associated with maternal COVID-19, rather than direct placental infection, is responsible for placental dysfunction and alteration of the placental transcriptome. We hypothesized that maternal circulating extracellular vesicles (EVs), altered by COVID-19 during pregnancy, contribute to placental dysfunction. To examine this hypothesis, we characterized maternal circulating EVs from pregnancies complicated by COVID-19 and tested their effects on trophoblast cell physiology in vitro. We found that the gestational timing of COVID-19 is a major determinant of circulating EV function and cargo. In vitro trophoblast exposure to EVs isolated from patients with an active infection at the time of delivery, but not EVs isolated from Controls, altered key trophoblast functions including hormone production and invasion. Thus, circulating EVs from participants with an active infection, both symptomatic and asymptomatic cases, can disrupt vital trophoblast functions. EV cargo differed between participants with COVID-19 and Controls, which may contribute to the disruption of the placental transcriptome and morphology. Our findings show that COVID-19 can have effects throughout pregnancy on circulating EVs and circulating EVs are likely to participate in placental dysfunction induced by COVID-19.
Project description:Immune system dysfunction is paramount in Coronavirus disease 2019 (COVID-19) severity and fatality rate. MAIT cells are innate-like T cells involved in mucosal immunity and protection against viral infections. Here, we studied the immune cell landscape, with emphasis on MAIT cells, in cohorts of 208 patients at various stages of disease activity. MAIT cell frequency is strongly reduced in blood. They display a strong activated and cytotoxic phenotype that is more pronounced in lungs. Blood MAIT cell alterations positively correlate with other innate cell activation; pro-inflammatory cytokines, notably IL-18; and with the severity and mortality of SARS-CoV-2 infection. We also identified a monocyte/macrophage Interferon-a-IL-18 cytokine shift and the ability of infected macrophages to induce cytotoxicity of MAIT cells in an MR1-dependent manner. Together our results suggest that altered MAIT cell functions due to IFN-a-IL-18 imbalance contribute to disease severity and their therapeutic manipulation might prevent deleterious inflammation in COVID-19 aggravation.