ROS-responsive polymer nanoparticles with enhanced loading of dexamethasone effectively modulate the lung injury microenvironment.

The acute lung injury (ALI) is an inflammatory disorder associated with cytokine storm, which activates various reactive oxygen species (ROS) signaling pathways and causes severe complications in patients as currently seen in coronavirus disease 2019 (COVID-19). There is an urgent need for medication of the inflammatory lung environment and effective delivery of drugs to lung to reduce the burden of high doses of medications and attenuate inflammatory cells and pathways. Herein, we prepared dexamethasone-loaded ROS-responsive polymer nanoparticles (PFTU@DEX NPs) by a modified emulsion approach, which achieved high loading content of DEX (11.61 %). DEX was released faster from the PFTU@DEX NPs in a ROS environment, which could scavenge excessive ROS efficiently both in vitro and in vivo. The PFTU NPs and PFTU@DEX NPs showed no hemolysis and cytotoxicity. Free DEX, PFTU NPs and PFTU@DEX NPs shifted M1 macrophages to M2 macrophages in RAW264.7 cells, and showed anti-inflammatory modulation to A549 cells in vitro. The PFTU@DEX NPs treatment significantly reduced the increased total protein concentration in BALF of ALI mice. The delivery of PFTU@DEX NPs decreased the proportion of neutrophils significantly, mitigated the cell apoptosis remarkably compared to the other groups, reduced M1 macrophages and increased M2 macrophages in vivo. Moreover, the PFTU@DEX NPs had the strongest ability to suppress the expression of NLRP3, Caspase1, and IL-1ß. Therefore, the PFTU@DEX NPs could efficiently suppress inflammatory cells, ROS signaling pathways, and cell apoptosis to ameliorate LPS-induced ALI. STATEMENT OF SIGNIFICANCE: The acute lung injury (ALI) is an inflammatory disorder associated with cytokine storm, which activates various reactive oxygen species (ROS) signaling pathways and causes severe complications in patients. There is an urgent need for medication of the inflammatory lung environment and effective delivery of drugs to modulate the inflammatory disorder and suppress the expression of ROS and inflammatory cytokines. The inhaled PFTU@DEX NPs prepared through a modified nanoemulsification method suppressed the activation of NLRP3, induced the polarization of macrophage phenotype from M1 to M2, and thereby reduced the neutrophil infiltration, inhibited the release of proteins and inflammatory mediators, and thus decreased the acute lung injury in vivo.

Mesenchymal stem cell treatment improves outcome of COVID-19 patients via multiple immunomodulatory mechanisms.

The infusion of coronavirus disease 2019 (COVID-19) patients with mesenchymal stem cells (MSCs) potentially improves clinical symptoms, but the underlying mechanism remains unclear. We conducted a randomized, single-blind, placebo-controlled (29 patients/group) phase II clinical trial to validate previous findings and explore the potential mechanisms. Patients treated with umbilical cord-derived MSCs exhibited a shorter hospital stay (P = 0.0198) and less time required for symptoms remission (P = 0.0194) than those who received placebo. Based on chest images, both severe and critical patients treated with MSCs showed improvement by day 7 (P = 0.0099) and day 21 (P = 0.0084). MSC-treated patients had fewer adverse events. MSC infusion reduced the levels of C-reactive protein, proinflammatory cytokines, and neutrophil extracellular traps (NETs) and promoted the maintenance of SARS-CoV-2-specific antibodies. To explore how MSCs modulate the immune system, we employed single-cell RNA sequencing analysis on peripheral blood. Our analysis identified a novel subpopulation of VNN2+ hematopoietic stem/progenitor-like (HSPC-like) cells expressing CSF3R and PTPRE that were mobilized following MSC infusion. Genes encoding chemotaxis factors - CX3CR1 and L-selectin - were upregulated in various immune cells. MSC treatment also regulated B cell subsets and increased the expression of costimulatory CD28 in T cells in vivo and in vitro. In addition, an in vivo mouse study confirmed that MSCs suppressed NET release and reduced venous thrombosis by upregulating kindlin-3 signaling. Together, our results underscore the role of MSCs in improving COVID-19 patient outcomes via maintenance of immune homeostasis.

Iron oxide nanoparticles augment the intercellular mitochondrial transfer-mediated therapy.

The transfer of mitochondria between cells has recently been revealed as a spontaneous way to protect the injured cells. However, the utilization of this natural transfer process for disease treatment is so far limited by its unsatisfactory transfer efficiency and selectivity. Here, we demonstrate that iron oxide nanoparticles (IONPs) can augment the intercellular mitochondrial transfer from human mesenchymal stem cells (hMSCs) selectively to diseased cells, owing to the enhanced formation of connexin 43­containing gap junctional channels triggered by ionized IONPs. In a mouse model of pulmonary fibrosis, the IONP-engineered hMSCs achieve a remarkable mitigation of fibrotic progression because of the promoted intercellular mitochondrial transfer, with no serious safety issues identified. The present study reports a potential method of using IONPs to enable hMSCs for efficient and safe transfer of mitochondria to diseased cells to restore mitochondrial bioenergetics.

Association of ACEi/ARB Use and Clinical Outcomes of COVID-19 Patients With Hypertension.

Objectives: Evidence has shown that angiotensin-converting enzyme 2 (ACE2), which can be upregulated after angiotensin-converting enzyme inhibitor (ACEi) and angiotensin receptor blocker (ARB) treatment, may play a dual role in the pathogenesis and progression of coronavirus disease 2019 (COVID-19). We aimed to assess the association between the use of ACEi/ARB and the outcome of COVID-19 patients with preexisting hypertension in non-endemic areas. Methods: From January 17, 2020, to February 19, 2020, 286 patients with hypertension were enrolled in this retrospective study out of 1,437 COVID-19 patients from 47 centers in Zhejiang and Jiangsu Province. The composite endpoints consisted of mechanical ventilation, intensive care unit (ICU) admission, or death. Cox proportional hazards analysis was performed to assess the association between ACEi/ARB and clinical outcomes of COVID-19 patients with hypertension. Results: In the main analysis, 103 patients receiving ACEi/ARB were compared with 173 patients receiving other regimens. Overall, 44 patients (15.94%) had an endpoint event. The risk probability of crude endpoints in the ACEi/ARB group (12.62%) was lower than that in the non-ACEi/ARB group (17.92%). After adjusting for confounding factors by inverse probability weighting, the results showed that the use of ACEi/ARB reduced the occurrence of end events by 47% [hazard ratio (HR) = 0.53; 95% CI, 0.34-0.83]. Similar results were obtained in multiple sensitivity analyses. Conclusions: In this retrospective study, among COVID-19 patients with hypertension, the use of ACEi/ARB is not associated with an increased risk of disease severity compared with patients without ACEi/ARB. The trends of beneficial effects of ACEi/ARB need to be further evaluated in randomized clinical trials.

Interferon-α-2b aerosol inhalation is associated with improved clinical outcomes in patients with coronavirus disease-2019.

AIMS: Type 1 interferon (IFN) is used to treat patients with coronavirus disease-2019 (COVID-19) but robust supporting evidence is lacking. We investigated the association between IFN-α-2b and the clinical outcomes of patients with COVID-19. METHODS: A total of 1401 patients were enrolled, with 852 (60.8%) patients receiving 5 000 000 U of IFN-α-2b via aerosol inhalation twice daily. The primary outcome was a composite measure consisting of mechanical ventilation, intensive care unit (ICU) admission and death. A subgroup analysis was performed to investigate the impact of the IFN-α-2b initiation schedule on symptom onset. RESULTS: The risk probability for crude endpoints was lower in the IFN-α-2b group (3.8%) than in the non-IFN-α-2b group (9.3%, P < .001). After adjusting the confounding factors, IFN-α-2b therapy achieved a reduction of 64% in occurrence of endpoint events (hazard ratio, 0.36; 95% confidence interval [CI], 0.21-0.62). In the subgroup analysis, compared with patients who received IFN-α-2b treatment 0-2 days after symptom onset, the hazard ratio for endpoints was 2.2 (95% CI, 0.43-11.13) in patients who received the therapy 3-5 days after symptom onset, 5.89 (95% CI, 0.99-35.05) in patients who received the therapy 6-8 days after symptom onset, and remained at a high level thereafter. CONCLUSIONS: IFN-α-2b aerosol inhalation therapy may be associated with improved clinical outcomes in patients with COVID-19, and delayed IFN-α-2b intervention was associated with increased probabilities of risk events. Further randomized clinical trials are needed to validate the preliminary findings of this study.

Epidemiological and clinical characteristics of 70 cases of coronavirus disease and concomitant hepatitis B virus infection: A multicentre descriptive study.

The interaction between existing chronic liver diseases caused by hepatitis B virus (HBV) infection and COVID-19 has not been studied. We analysed 70 COVID-19 cases combined with HBV infection (CHI) to determine the epidemiological, clinical characteristics, treatment and outcome. We investigated clinical presentation, imaging and laboratory parameters of COVID-19 patients of seven hospitals from Jan 20 to March 20, 2020. Multivariate analysis was used to analyse risk factors for progression of patients with COVID-19 combined with HBV infection. Compared with COVID-19 without HBV infection (WHI) group, patients with dual infection had a higher proportion of severe/critically ill disease (32.86% vs. 15.27%, P = .000), higher levels of alanine aminotransferase (ALT), aspartate transaminase (AST) and activated partial thromboplastin (APTT) [50(28-69)vs 21(14-30), P = .000; 40(25-54) vs 23(18-30), P = .000; 34.0(27.2-38.7) vs 37.2(31.1-41.4), P = .031]. The utilization rates of Arbidol and immunoglobulin were significantly higher than those in the co-infected group [48.57% vs. 35.64%, P < .05; 21.43% vs. 8.18%, P < .001], while the utilization rate of chloroquine phosphate was lower (1.43% vs 14.00%, P < .05) in the co-infected patients group. Age and c-reactive protein (CRP) level were independent risk factors for recovery of patients with COVID-19 combined with HBV infection. The original characteristics of COVID-19 cases combined with HBV infection were higher rate of liver injury, coagulation disorders, severe/critical tendency and increased susceptibility. The elderly and patients with higher level of CRP were more likely to experience a severe outcome of COVID-19.

Recurrence of SARS-CoV-2 nucleic acid positive test in patients with COVID-19: a report of two cases.

BACKGROUND: The recurrence of positive SARS-CoV-2 nucleic acid test results in patients with COVID-19 is becoming more important and warrants more attention. CASE PRESENTATION: This study reports 2 cases, a child with mild COVID-19 and an adult female with moderate COVID-19, who were discharged after three consecutive negative nucleic acid tests and were later readmitted to the hospital for recurrence of SARS-CoV-2 nucleic acid positivity. By tracking the patients' symptoms, serum antibodies, and imaging manifestations after readmission, we found that they showed a trend of gradual improvement and recovery throughout treatment. They were cured without additional treatment, with the appearance of antibodies and the recovery of immune functions. CONCLUSIONS: It is deemed extremely necessary to improve the discharge standard of care. At the same time, nucleic acid detection is recommended to increase the dynamic monitoring of serum antibodies and imaging, strengthen the management of discharged patients, and appropriately extend the home or centralized isolation time.

Clinical Characteristics of Imported Cases of Coronavirus Disease 2019 (COVID-19) in Jiangsu Province: A Multicenter Descriptive Study.

BACKGROUND: We aimed to report the clinical characteristics of imported cases of coronavirus disease 2019 (COVID-19) in Jiangsu Province. METHODS: We retrospectively investigated the clinical, imaging, and laboratory characteristics of confirmed cases of COVID-19 with World Health Organization interim guidance in 3 grade IIIA hospitals of Jiangsu from 22 January to 14 February 2020. Real-time RT-PCR was used to detect the new coronavirus in respiratory samples. RESULTS: Of the 80 patients infected with COVID-19, 41 were female, with a median age of 46.1 years. Except for 3 severe patients, the rest of the 77 patients exhibited mild or moderate symptoms. Nine patients were unconfirmed until a third nucleic acid test; 38 cases had a history of chronic diseases. The main clinical manifestations of the patients were fever and cough, which accounted for 63 (78.75%) and 51 (63.75%) cases, respectively. Only 3 patients (3.75%) showed liver dysfunction. Imaging examination showed that 55 patients (68.75%) showed abnormal density shadow and 25 cases (31.25%) had no abnormal density shadow in the parenchyma of both lungs. Currently, 21 cases have been discharged from the hospital, and no patient died. The average length of stay for discharged patients was 8 days. CONCLUSIONS: Compared with the cases in Wuhan, the cases in Jiangsu exhibited mild or moderate symptoms and no obvious gender susceptibility. The proportion of patients having liver dysfunction and abnormal CT imaging was relatively lower than that in Wuhan. Notably, infected patients may be falsely excluded based on 2 consecutively negative respiratory pathogenic nucleic acid test results.

Development and validation of a risk stratification model for screening suspected cases of COVID-19 in China.

How to quickly identify high-risk populations is critical to epidemic control. We developed and validated a risk prediction model for screening SARS-CoV-2 infection in suspected cases with an epidemiological history. A total of 1019 patients, ≥13 years of age, who had an epidemiological history were enrolled from fever clinics between January 2020 and February 2020. Among 103 (10.11%) cases of COVID-19 were confirmed. Multivariable analysis summarized four features associated with increased risk of SARS-CoV-2 infection, summarized in the mnemonic COVID-19-REAL: radiological evidence of pneumonia (1 point), eosinophils < 0.005 × 109/L (1 point), age ≥ 32 years (2 points), and leukocytes < 6.05 × 109 /L (1 point). The area under the ROC curve for the training group was 0.863 (95% CI, 0.813 - 0.912). A cut-off value of less than 3 points for COVID-19-REAL was assigned to define the low-risk population. Only 10 (2.70%) of 371 patients were proved to be SARS-CoV-2 positive, with a negative predictive value of 0.973. External validation was similar. This study provides a simple, practical, and robust screening model, COVID-19-REAL, able to identify populations at high risk for SARS-CoV-2 infection.

Liver diseases in COVID-19: Etiology, treatment and prognosis.

In December 2019, a novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified in Wuhan, China causing coronavirus disease-2019 (COVID-19). Numerous studies have shown varying degrees of liver damage in patients infected with SARS-CoV-2. However, in previous case studies of COVID-19, the exact cause of liver injury has not been clearly elucidated, nor is there clear evidence of the interaction between liver injury and COVID-19. This study will analyze the causes of liver injury in COVID-19 and the influence of liver-related complications on the treatment and prognosis of COVID-19.

Immune Characteristics of Patients with Coronavirus Disease 2019 (COVID-19).

Up to now, little is known about the detailed immune profiles of COVID-19 patients from admission to discharge. In this study we retrospectively reviewed the clinical and laboratory characteristics of 18 COVID-19 patients from January 30, 2020 to February 21, 2020. These patients were divided into two groups; group 1 had a severe acute respiratory syndrome coronavirus 2 nucleic acid-positive duration for more than 15 days (n = 6) and group 2 had a nucleic acid-positive duration for less than 15 days (n = 12). Group 1 patients had lower level of peripheral blood lymphocytes (0.40 vs. 0.78 ×109/L, p = 0.024) and serum potassium (3.36 vs. 3.79 mmol/L, p = 0.043) on admission but longer hospitalization days (23.17 vs. 15.75 days, p < 0.001) compared to Group 2 patients. Moreover, baseline level of lymphocytes (r = -0.62, p = 0.006) was negatively correlated with the nucleic acid-positive duration. Additionally, lymphocytes (420.83 vs. 1100.56 /µL), T cells (232.50 vs. 706.78 /µL), CD4+ T cells (114.67 vs. 410.44 /µL), and CD8+ T cells (94.83 vs. 257.44 /µL) in the peripheral blood analyzed by flow cytometry were significantly different between Group 1and Group 2. Furthermore, there was also a negative correlation between lymphocytes (r = -0.54, p = 0.038) or T cells (r = -0.55, p = 0.034) at diagnosis and the nucleic acid-positive duration, separately. In conclusion, the patients with nucleic acid-positive ≥ 15 days had significantly decreased lymphocytes, T cell and its subsets compared to those who remained positive for less than 15 days.