SARS-CoV-2 restructures host chromatin architecture.

Some viruses restructure host chromatin, influencing gene expression, with implications for disease outcome. Whether this occurs for SARS-CoV-2, the virus causing COVID-19, is largely unknown. Here we characterized the 3D genome and epigenome of human cells after SARS-CoV-2 infection, finding widespread host chromatin restructuring that features widespread compartment A weakening, A-B mixing, reduced intra-TAD contacts and decreased H3K27ac euchromatin modification levels. Such changes were not found following common-cold-virus HCoV-OC43 infection. Intriguingly, the cohesin complex was notably depleted from intra-TAD regions, indicating that SARS-CoV-2 disrupts cohesin loop extrusion. These altered 3D genome/epigenome structures correlated with transcriptional suppression of interferon response genes by the virus, while increased H3K4me3 was found in the promoters of pro-inflammatory genes highly induced during severe COVID-19. These findings show that SARS-CoV-2 acutely rewires host chromatin, facilitating future studies of the long-term epigenomic impacts of its infection.

Fulminant lung fibrosis in non-resolvable COVID-19 requiring transplantation.

BACKGROUND: Coronavirus Disease 2019 (COVID-19) can lead to the development of acute respiratory distress syndrome (ARDS). In some patients with non-resolvable (NR) COVID-19, lung injury can progress rapidly to the point that lung transplantation is the only viable option for survival. This fatal progression of lung injury involves a rapid fibroproliferative response and takes on average 15 weeks from initial symptom presentation. Little is known about the mechanisms that lead to this fulminant lung fibrosis (FLF) in NR-COVID-19. METHODS: Using a pre-designed unbiased PCR array for fibrotic markers, we analyzed the fibrotic signature in a subset of NR-COVID-19 lungs. We compared the expression profile against control lungs (donor lungs discarded for transplantation), and explanted tissue from patients with idiopathic pulmonary fibrosis (IPF). Subsequently, RT-qPCR, Western blots and immunohistochemistry were conducted to validate and localize selected pro-fibrotic targets. A total of 23 NR-COVID-19 lungs were used for RT-qPCR validation. FINDINGS: We revealed a unique fibrotic gene signature in NR-COVID-19 that is dominated by a hyper-expression of pro-fibrotic genes, including collagens and periostin. Our results also show a significantly increased expression of Collagen Triple Helix Repeat Containing 1(CTHRC1) which co-localized in areas rich in alpha smooth muscle expression, denoting myofibroblasts. We also show a significant increase in cytokeratin (KRT) 5 and 8 expressing cells adjacent to fibroblastic areas and in areas of apparent epithelial bronchiolization. INTERPRETATION: Our studies may provide insights into potential cellular mechanisms that lead to a fulminant presentation of lung fibrosis in NR-COVID-19. FUNDING: National Institute of Health (NIH) Grants R01HL154720, R01DK122796, R01DK109574, R01HL133900, and Department of Defense (DoD) Grant W81XWH2110032 to H.K.E. NIH Grants: R01HL138510 and R01HL157100, DoD Grant W81XWH-19-1-0007, and American Heart Association Grant: 18IPA34170220 to H.K.-Q. American Heart Association: 19CDA34660279, American Lung Association: CA-622265, Parker B. Francis Fellowship, 1UL1TR003167-01 and The Center for Clinical and Translational Sciences, McGovern Medical School to X.Y.

SARS-CoV-2 Infection: Host Response, Immunity, and Therapeutic Targets.

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has resulted in a global pandemic with severe socioeconomic effects. Immunopathogenesis of COVID-19 leads to acute respiratory distress syndrome (ARDS) and organ failure. Binding of SARS-CoV-2 spike protein to human angiotensin-converting enzyme 2 (hACE2) on bronchiolar and alveolar epithelial cells triggers host inflammatory pathways that lead to pathophysiological changes. Proinflammatory cytokines and type I interferon (IFN) signaling in alveolar epithelial cells counter barrier disruption, modulate host innate immune response to induce chemotaxis, and initiate the resolution of inflammation. Here, we discuss experimental models to study SARS-CoV-2 infection, molecular pathways involved in SARS-CoV-2-induced inflammation, and viral hijacking of anti-inflammatory pathways, such as delayed type-I IFN response. Mechanisms of alveolar adaptation to hypoxia, adenosinergic signaling, and regulatory microRNAs are discussed as potential therapeutic targets for COVID-19.

Optimize the management of urological tube-related emergencies during the coronavirus disease 2019 (COVID-19) pandemic.

BACKGROUND: To introduce and determine the value of optimized strategies for the management of urological tube-related emergencies with increased incidence, complexity and operational risk during the global spread of coronavirus disease 2019 (COVID-19). METHODS: All emergent urological patients at Tongji Hospital, Wuhan, during the period of January 23 (the beginning of lockdown in Wuhan) to March 23, 2020, and the corresponding period in 2019 were recruited to form this study's COVID-19 group and control group, respectively. Tongji Hospital has the most concentrated and strongest Chinese medical teams to treat the largest number of severe COVID-19 patients. Patients in the control group were routinely treated, while patients in the COVID-19 group were managed following the optimized principles and strategies. The case incidence for each type of tube-related emergency was recorded. Baseline characteristics and management outcomes (surgery time, secondary complex operation rate, readmission rate, COVID-19 infection rate) were analyzed and compared across the control and COVID-19 periods. RESULTS: The total emergent urological patients during the COVID-19 period was 42, whereas during the control period, it was 124. The incidence of tube-related emergencies increased from 53% to 88% (P<0.001) during the COVID-19 period. In particular, the incidence of nephrostomy tube-related (31% vs. 15%, P=0.027) and single-J stent-related problems (19% vs. 6%, P=0.009) increased significantly. The mean surgery times across the two periods were comparable. The number of secondary complex operations increased from 12 (18%) to 14 (38%) (P=0.028) during the COVID 19-period. The number of 2-week postoperative readmission decreased from 10 (15%) to 1 (3%) (P=0.049). No participants contracted during the COVID-19 period. CONCLUSIONS: Urological tube-related emergencies have been found to have a higher incidence and require more complicated and dangerous operations during the COVID-19 pandemic. However, the optimized management strategies introduced in this study are efficient, and safe for both urologists and patients.

Adenosine at the Interphase of Hypoxia and Inflammation in Lung Injury.

Hypoxia and inflammation often coincide in pathogenic conditions such as acute respiratory distress syndrome (ARDS) and chronic lung diseases, which are significant contributors to morbidity and mortality for the general population. For example, the recent global outbreak of Coronavirus disease 2019 (COVID-19) has placed viral infection-induced ARDS under the spotlight. Moreover, chronic lung disease ranks the third leading cause of death in the United States. Hypoxia signaling plays a diverse role in both acute and chronic lung inflammation, which could partially be explained by the divergent function of downstream target pathways such as adenosine signaling. Particularly, hypoxia signaling activates adenosine signaling to inhibit the inflammatory response in ARDS, while in chronic lung diseases, it promotes inflammation and tissue injury. In this review, we discuss the role of adenosine at the interphase of hypoxia and inflammation in ARDS and chronic lung diseases, as well as the current strategy for therapeutic targeting of the adenosine signaling pathway.

No detection of SARS-CoV-2 from urine, expressed prostatic secretions, and semen in 74 recovered COVID-19 male patients: A perspective and urogenital evaluation.

BACKGROUND: The coronavirus disease 2019 (COVID-19) has been spreading all over the world since December 2019. However, medical information regarding the urogenital involvement in recovered COVID-19 patients is limited or unknown. OBJECTIVES: To comprehensively evaluate urogenital involvement in recovered COVID-19 patients. MATERIALS AND METHODS: Men aged between 20 years and 50 years who were diagnosed with SARS-CoV-2 infection and recovered when the study was conducted were enrolled in our study. Demographic and clinical characteristics, and history of hospitalization were collected and analyzed. Urine, expressed prostatic secretions (EPSs), and semen samples were collected for SARS-CoV-2 RNA detection. Semen quality and hormonal profiles were analyzed. RESULTS: Among 74 male recovered COVID-19 patients, 11 (14.9%) were asymptomatic, classified into mild type, and 31 (41.9%) were classified into moderate type. The remaining patients (32/74, 43.2%) had severe pneumonia. No critically ill recovered COVID-19 patient was recruited in our cohort. The median interval between last positive pharyngeal swab RT-PCR test and semen samples collection was 80 days (IQR, 64-93). The median age was 31 years (IQR, 27-36; range, 21-49), and the median body mass index (BMI) was 24.40 (IQR, 22.55-27.30). Forty-five (61.6%) men were married, and 28 (38.4%) were unmarried. Fifty-three (72.6%) patients denied cigarette smoking, 18 (24.7%) were active smokers, and 2 of them were past smokers. The majority of our participants (53/74, 72.6%) did not consume alcohol. Fever occurred in most of the patients (75.3%), and 63 of them had abnormal chest CT images. Only one patient complained of scrotal discomfort during the course of COVID-19, which was ruled out orchitis by MRI (data not shown). A total of 205 samples were collected for SARS-CoV-2 detection (74 urine samples, 70 semen samples, and 61 EPS samples). However, viral nucleic acid was not detected in body fluids from the urogenital system. In terms of hormonal profiles, the levels of FSH, LH, testosterone, and estradiol were 5.20 [4.23] mIU/mL, 3.95 [1.63] mIU/mL, 3.65 [1.19] ng/mL, and 39.48 [12.51] pg/mL, respectively. And these values were within the normal limits. The overall semen quality of recovered COVID-19 patients was above the lower reference limit released by the WHO. While compared with healthy control, sperm concentration, total sperm count, and total motility were significantly declined. In addition, different clinical types of COVID-19 have no significant difference in semen parameters, but total sperm count showed a descending trend. Interestingly, subjects with a longer recovery time showed worse data for sperm quality. Small sample size and lacking semen parameters before the infection are the major limitations of our study. DISCUSSION AND CONCLUSIONS: To the best of our knowledge, it is the largest cohort study with longest follow-up for urogenital evaluation comprehensively so far. Direct urogenital involvement was not found in the recovered COVID-19 male patients. SARS-CoV-2 RNA was undetectable in the urogenital secretions, and semen quality declined slightly, while hormonal profiles remained normal. Moreover, patients with a long time (≥90 days) since recovery had lower total sperm count. Great attention and further study should be conducted and follow-up on the reproductive function in the following months.