Human mesenchymal stem cell therapy in severe COVID-19 patients: 2-year follow-up results of a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Long-term effects of human mesenchymal stem cell (MSC) treatment on COVID-19 patients have not been fully characterized. The aim of this study was to evaluate the safety and efficacy of a MSC treatment administered to severe COVID-19 patients enrolled in our previous randomized, double-blind, placebo-controlled clinical trial (NCT04288102). METHODS: A total of 100 patients experiencing severe COVID-19 received either MSC treatment (n = 65, 4 × 107 cells per infusion) or a placebo (n = 35) combined with standard of care on days 0, 3, and 6. Patients were subsequently evaluated 18 and 24 months after treatment to evaluate the long-term safety and efficacy of the MSC treatment. Outcomes measured included: 6-min walking distance (6-MWD), lung imaging, quality of life according to the Short Form 36 questionnaire (SF-36), COVID-19-related symptoms, titers of SARS-CoV-2 neutralizing antibodies, tumor markers, and MSC-related adverse events (AEs). FINDINGS: Two years after treatment, a marginally smaller proportion of patients had a 6-MWD below the lower limit of the normal range in the MSC group than in the placebo group (OR = 0.19, 95% CI: 0.04-0.80, Fisher's exact test, p = 0.015). At month 18, the general health score from the SF-36 was higher in the MSC group than in the placebo group (50.00 vs. 35.00, 95% CI: 0.00-20.00, Wilcoxon rank sum test, p = 0.018). Total severity score of lung imaging and the titer of neutralizing antibodies were similar between the two groups at months 18 and 24. There was no difference in AEs or tumor markers at the 2-year follow-up between the two groups. INTERPRETATION: Long-term safety was observed for the COVID-19 patients who received MSC treatment. However, efficacy of MSC treatment was not significantly sustained through the end of the 2-year follow-up period. FUNDING: The National Key Research and Development Program of China (2022YFA1105604, 2020YFC0860900, 2022YFC2304401), the specific research fund of The Innovation Platform for Academicians of Hainan Province (YSPTZX202216) and the Fund of National Clinical Center for Infectious Diseases, PLA General Hospital (NCRC-ID202105,413FZT6).

Effect of Methylprednisolone on Mortality and Clinical Courses in Patients with Severe COVID-19: A Propensity Score Matching Analysis

Background Whether methylprednisolone therapy can reduce the mortality rate of patients with severe coronavirus disease 2019 (COVID-19) remains controversial, and its effects on the length of hospital stay and virus shedding time are also unknown. This retrospective study investigates the previous issues to provide more evidence for methylprednisolone treatment in severe COVID-19. Methods This retrospective study included 563 of 4827 patients with confirmed COVID-19 admitted to Wuhan Huoshenshan Hospital or Wuhan Guanggu Hospital between February 3, 2020 and March 30, 2020 who met the screening criteria. The participants' epidemiological and demographic data, comorbidities, laboratory test results, treatments, outcomes, and vital clinical time points were extracted from electronic medical records. The primary outcome was in-hospital death, and the secondary outcomes were 2 clinical courses: length from admission to viral clearance and discharge. Univariate and multivariate logistic or linear regression analyses were used to assess the role of methylprednisolone in different outcomes. Propensity score matching was performed to control for confounding factors. Results Of the 563 patients who met the screening criteria and were included in the subsequent analysis, 138 were included in the methylprednisolone group and 425 in the nonmethylprednisolone group. The in-hospital death rate between the methylprednisolone and nonmethylprednisolone groups showed a significant difference (23.91% vs. 1.65%, P < 0.001), which was maintained after propensity score matching (13.98% vs. 5.38%, P = 0.048). However, univariate logistic analysis in the matched groups showed that methylprednisolone treatment (odds ratio [OR], 5.242;95% confidence interval [CI], 0.802 to 34.246;P = 0.084) was not a risk factor for in-hospital death in severe patients. Further multivariate logistic regression analysis found comorbidities (OR, 3.327;95% CI, 1.702 to 6.501;P < 0.001), lower lymphocyte count (OR, 0.076;95% CI, 0.012 to 0.461;P = 0.005), higher lactate dehydrogenase (LDH) levels (OR, 1.008;95% CI, 1.003 to 1.013;P = 0.002), and anticoagulation therapy (OR, 11.187;95% CI, 2.459 to 50.900;P = 0.002) were associated with in-hospital mortality. Multivariate linear regression analysis in the matched groups showed that methylprednisolone treatment was not a risk factor for a prolonged duration from admission to viral clearance (β Value 0.081;95% CI, −1.012 to 3.657;P = 0.265) or discharge (β Value 0.114;95% CI, −0.723 to 6.408;P = 0.117). d-dimer (β Value, 0.144;95% CI, 0.012 to 0.817;P = 0.044), LDH (β Value 0.260;95% CI, 0.010 to 0.034;P < 0.001), and antiviral therapy (β Value 0.220;95% CI, 1.373 to 6.263;P = 0.002) were associated with a longer length from admission to viral clearance. The lymphocyte count (β Value −0.206;95% CI, −6.248 to −1.197;P = 0.004), LDH (β Value 0.231;95% CI, 0.012 to 0.048;P = 0.001), antiviral therapy (β Value 0.143;95% CI, 0.058 to 7.497;P = 0.047), and antibacterial therapy (β Value 0.152;95% CI, 0.133 to 8.154;P = 0.043) were associated with a longer hospitalization duration from admission to discharge. Further stratified analysis revealed that the low daily dose group (≤60 mg/d) and the low total dose group (≤200 mg) had shorter duration from admission to viral clearance (Z=−2.362, P = 0.018;Z=−2.010, P = 0.044) and a shorter hospital stay (Z=−2.735, P = 0.006;Z=−3.858, P < 0.001). Conclusions In patients with severe COVID-19, methylprednisolone is safe and does not prolong the duration from admission to viral clearance or discharge. Low-dose, short-term methylprednisolone treatment may be more beneficial in shortening the disease course.

Uncertainty stress and self-rated health during the early stage of the COVID-19 outbreak.

Objectives: The COVID-19 crisis caused unparalleled uncertainty stress and health-related symptoms among Chinese residents. This study aimed to characterize stress status during the early stage of the pandemic and explore the inner mechanism between uncertainty stress and self-rated health. Setting/participants: A cross-sectional design was conducted online from February 7 to 14, 2020. A total of 2534 Chinese participants were surveyed. Main outcome measures: Uncertainty stress, negative affect, sleep quality, and health status were measured by self-report. A sequential mediation model using bootstrapping method was applied to test these relationships. Results: Age, place of residence, marital status, occupation, household annual income, infection, and quarantine status significantly correlated with uncertainty stress. Higher uncertainty stress was negatively related with self-rated health (r = -0.256, p < 0.01) and positively associated with higher negative emotions (r = 0.646, p < 0.01). The sequential mediation model found total indirect effect (ß = -0.014, 95%C.I. = -0.017-0.010) and direct effect (ß = -0.010, 95%C.I. = -0.015-0.005) were significant in the relationship between uncertainty stress and self-rated health with mediating by negative affect and subjective sleep quality. Conclusions: Findings provided evidence-based information for stakeholders designing and implementing intervention strategies by providing psychological consultation services and public education to manage uncertainty stress and minimize the damage of negative affect and poor sleep.

Effect of Methylprednisolone on Mortality and Clinical Courses in Patients with Severe COVID-19: A Propensity Score Matching Analysis.

Background: Whether methylprednisolone therapy can reduce the mortality rate of patients with severe coronavirus disease 2019 (COVID-19) remains controversial, and its effects on the length of hospital stay and virus shedding time are also unknown. This retrospective study investigates the previous issues to provide more evidence for methylprednisolone treatment in severe COVID-19. Methods: This retrospective study included 563 of 4827 patients with confirmed COVID-19 admitted to Wuhan Huoshenshan Hospital or Wuhan Guanggu Hospital between February 3, 2020 and March 30, 2020 who met the screening criteria. The participants' epidemiological and demographic data, comorbidities, laboratory test results, treatments, outcomes, and vital clinical time points were extracted from electronic medical records. The primary outcome was in-hospital death, and the secondary outcomes were 2 clinical courses: length from admission to viral clearance and discharge. Univariate and multivariate logistic or linear regression analyses were used to assess the role of methylprednisolone in different outcomes. Propensity score matching was performed to control for confounding factors. Results: Of the 563 patients who met the screening criteria and were included in the subsequent analysis, 138 were included in the methylprednisolone group and 425 in the nonmethylprednisolone group. The in-hospital death rate between the methylprednisolone and nonmethylprednisolone groups showed a significant difference (23.91% vs. 1.65%, P < 0.001), which was maintained after propensity score matching (13.98% vs. 5.38%, P = 0.048). However, univariate logistic analysis in the matched groups showed that methylprednisolone treatment (odds ratio [OR], 5.242; 95% confidence interval [CI], 0.802 to 34.246; P = 0.084) was not a risk factor for in-hospital death in severe patients. Further multivariate logistic regression analysis found comorbidities (OR, 3.327; 95% CI, 1.702 to 6.501; P < 0.001), lower lymphocyte count (OR, 0.076; 95% CI, 0.012 to 0.461; P = 0.005), higher lactate dehydrogenase (LDH) levels (OR, 1.008; 95% CI, 1.003 to 1.013; P = 0.002), and anticoagulation therapy (OR, 11.187; 95% CI, 2.459 to 50.900; P = 0.002) were associated with in-hospital mortality. Multivariate linear regression analysis in the matched groups showed that methylprednisolone treatment was not a risk factor for a prolonged duration from admission to viral clearance (ß Value 0.081; 95% CI, -1.012 to 3.657; P = 0.265) or discharge (ß Value 0.114; 95% CI, -0.723 to 6.408; P = 0.117). d-dimer (ß Value, 0.144; 95% CI, 0.012 to 0.817; P = 0.044), LDH (ß Value 0.260; 95% CI, 0.010 to 0.034; P < 0.001), and antiviral therapy (ß Value 0.220; 95% CI, 1.373 to 6.263; P = 0.002) were associated with a longer length from admission to viral clearance. The lymphocyte count (ß Value -0.206; 95% CI, -6.248 to -1.197; P = 0.004), LDH (ß Value 0.231; 95% CI, 0.012 to 0.048; P = 0.001), antiviral therapy (ß Value 0.143; 95% CI, 0.058 to 7.497; P = 0.047), and antibacterial therapy (ß Value 0.152; 95% CI, 0.133 to 8.154; P = 0.043) were associated with a longer hospitalization duration from admission to discharge. Further stratified analysis revealed that the low daily dose group (≤60 mg/d) and the low total dose group (≤200 mg) had shorter duration from admission to viral clearance (Z=-2.362, P = 0.018; Z=-2.010, P = 0.044) and a shorter hospital stay (Z=-2.735, P = 0.006; Z=-3.858, P < 0.001). Conclusions: In patients with severe COVID-19, methylprednisolone is safe and does not prolong the duration from admission to viral clearance or discharge. Low-dose, short-term methylprednisolone treatment may be more beneficial in shortening the disease course.

It is time to improve the acceptance of COVID-19 vaccines among people with chronic diseases: A systematic review and meta-analysis.

This study aims to investigated COVID-19 vaccine acceptance among people with chronic diseases and the factors correlating with their vaccination hesitancy. The articles were searched in PubMed, Ovid, EMBASE, and web of science databases between December 2019 and October 2022. Cross-sectional studies, including the acceptance of the COVID-19 vaccine by patients with chronic diseases (≥18 years old), were included in this study. The outcomes included the proportion and 95% confidence interval (95% CI) of chronic disease patients willing to be vaccinated and the odds ratio (OR) and 95% CI of correlating factors. The source of heterogeneity was analyzed through meta-regression and subgroup analysis. We included 31 studies involving 57 875 patients with chronic disease. The overall COVID-19 vaccine acceptance among patients with chronic disease was 0.65 (95% CI, 0.59-0.72). The acceptance among the elderly patients was 0.53 (95% CI, 0.26-0.80). South America had the highest COVID-19 vaccine acceptance rate and Asia the lowest, while on a country level, the United Kingdom had the highest acceptance rate among patients with chronic diseases. People with rheumatic immune diseases had the lowest rate of COVID-19 vaccine acceptance. Concerns about vaccine safety had a statistically different effect on acceptance. Overall, the health systems ought to focus on educating specific groups of individuals on the benefits of COVID-19 vaccination and addressing safety concerns.

Effect of methylprednisolone therapy on hospital stay and viral clearance in patients with moderate COVID-19

Background The benefits and harms of methylprednisolone treatment in patients with moderate coronavirus disease 2019 (COVID-19) remain controversial. In this study, we investigated the effect of methylprednisolone on mortality rate, viral clearance, and hospitalization stay in patients with moderate COVID-19. Methods This retrospective study included 4827 patients admitted to Wuhan Huoshenshan and Wuhan Guanggu hospitals from February to March 2020 diagnosed with COVID-19 pneumonia. The participants’ epidemiological and demographic data, comorbidities, laboratory test results, treatments, outcomes, and vital clinical time points were extracted from electronic medical records. The primary outcome was in-hospital death;secondary outcomes were time from admission to viral clearance and hospital stay. Univariate and multivariate logistic or linear regression analysis were used to assess the roles of methylprednisolone in different outcomes. The propensity score matching (PSM) method was used to control for confounding factors. Results A total of 1320 patients were included in this study, of whom 100 received methylprednisolone. Overall in-hospital mortality was 0.91% (12/1320);the 12 patients who died were all in the methylprednisolone group, though multivariate logistic regression analysis showed methylprednisolone treatment was not a risk factor for in-hospital death in moderate patients before or after adjustment for confounders by PSM. Methylprednisolone treatment was correlated with longer length from admission to viral clearance time and hospital stay before and after adjustment for confounders. Conclusions Methylprednisolone therapy was not associated with increased in-hospital mortality but with delayed viral clearance and extended hospital stay in moderate COVID-19 patients.

The Association Between the Albumin and Viral Negative Conversion Rate in Patients Infected with Novel Coronavirus Disease 2019 (COVID-19).

Purpose: The novel coronavirus disease 2019 (COVID-19) epidemic is the severe global pandemic with large numbers of infected cases and deaths in recent decades. The previous studies were all about the influence of albumin (ALB) for the severity and mortality of in-patients infected with COVID-19. But few studies exist about the influence factors to achieve viral negative conversion. Therefore, this study conducted an exploratory study to investigate the effect of albumin on negative conversion rate. Methods: Among the 190 hospitalized patients with moderate COVID-19 who had a course of disease longer than 30 days, 102 achieved viral negative conversion in 30-45 days and 88 not after 45 days. Taking other variables as concomitant variable, Cox proportional hazard regression model was applied to explore the influence of albumin to negative conversion rate under various factors. Results: By comparing patients who could and could not achieve the finally viral negative conversion, a possible nonlinear relationship between the continuous variables and clinical outcomes was examined by a restricted cubic spline regression model. An association was found between albumin levels and hazard ratio of viral negative conversion rate (P = 0.027). The increase of albumin was accompanied with decreases of hazard ratio of viral negative conversion rate (the value of albumin <38 g/L). But when the value of albumin was higher than 38 g/L, the hazard ratio of viral negative conversion rate approached 1, it means that albumin is not a risk factor for the viral negative conversion rate of COVID-19 disease. Conclusion: For patients with COVID-19, albumin is a common and observed laboratory parameter. It is associated with final viral negative conversion rate although its underlying mechanism and relationship with the viral negative conversion rate still need to be clarified.

Multiscale heterogeneous optimal lockdown control for COVID-19 using geographic information.

We study the problem of synthesizing lockdown policies-schedules of maximum capacities for different types of activity sites-to minimize the number of deceased individuals due to a pandemic within a given metropolitan statistical area (MSA) while controlling the severity of the imposed lockdown. To synthesize and evaluate lockdown policies, we develop a multiscale susceptible, infected, recovered, and deceased model that partitions a given MSA into geographic subregions, and that incorporates data on the behaviors of the populations of these subregions. This modeling approach allows for the analysis of heterogeneous lockdown policies that vary across the different types of activity sites within each subregion of the MSA. We formulate the synthesis of optimal lockdown policies as a nonconvex optimization problem and we develop an iterative algorithm that addresses this nonconvexity through sequential convex programming. We empirically demonstrate the effectiveness of the developed approach by applying it to six of the largest MSAs in the United States. The developed heterogeneous lockdown policies not only reduce the number of deceased individuals by up to 45 percent over a 100 day period in comparison with three baseline lockdown policies that are less heterogeneous, but they also impose lockdowns that are less severe.

Human mesenchymal stem cells treatment for severe COVID-19: 1-year follow-up results of a randomized, double-blind, placebo-controlled trial.

BACKGROUND: The long-term consequences of human umbilical cord-derived mesenchymal stem cell (UC-MSC) treatment for COVID-19 patients are yet to be reported. This study assessed the 1-year outcomes in patients with severe COVID-19, who were recruited in our previous UC-MSC clinical trial. METHODS: In this prospective, longitudinal, cohort study, 100 patients enrolled in our phase 2 trial were prospectively followed up at 3-month intervals for 1 year to evaluate the long-term safety and effectiveness of UC-MSC treatment. The primary endpoint was an altered proportion of whole-lung lesion volumes measured by high-resolution CT. Other imaging outcomes, 6 min walking distance (6-MWD), lung function, plasma biomarkers, and adverse events were also recorded and analyzed. This trial was registered with ClinicalTrials.gov (NCT04288102). FINDINGS: MSC administration improved in whole-lung lesion volume compared with the placebo with a difference of -10.8% (95% CI: -20.7%, -1.5%, p = 0.030) on day 10. MSC also reduced the proportion of solid component lesion volume compared with the placebo at each follow-up point. More interestingly, 17.9% (10/56) of patients in the MSC group had normal CT images at month 12, but none in the placebo group (p = 0.013). The incidence of symptoms was lower in the MSC group than in the placebo group at each follow-up time. Neutralizing antibodies were all positive, with a similar median inhibition rate (61.6% vs. 67.6%) in both groups at month 12. No difference in adverse events at the 1-year follow-up and tumor markers at month 12 were observed between the two groups. INTERPRETATION: UC-MSC administration achieves a long-term benefit in the recovery of lung lesions and symptoms in COVID-19 patients. FUNDING: The National Key R&D Program of China, the Innovation Groups of the National Natural Science Foundation of China, and the National Science and Technology Major Project.

Improvements and Operation Methods of HVAC System in Shanghai Library(East Zone) Under the Background of COVID-19's Normalization Prevention and Control

In the first half of 2020, the construction of Shanghai Library(East Zone) was delayed by the COVID-19's outbreak. As time goes on, the epidemic is spreading in many parts of the world. Although the epidemic in China has been effectively controlled, such grave public health emergencies ring the alarm bell for social public. Relative authorities have issued guidelines, measures and specifications for how to use HVAC system under these circumstances. By analyzing these new codes and standards, the HVAC system in Shanghai Library(East Zone) can operate as design. Because the design outdoor air rates and filter's performance meet the standard requirements. At the end of Shanghai Library East's construction, some operation methods and adaptable improvements in filters are given to increase the security level. Five methods, including:(1)enhancement of natural ventilation,(2)control of the occupant density,(3)installation of filters,(4)increase of the outdoor air rates for ventilation according to the risk level of epidemic situation,(5)cleaning, disinfection and inspection of the HVAC equipment. Given by this research can also be applied to similar public buildings.

A multi-omics investigation of the composition and function of extracellular vesicles along the temporal trajectory of COVID-19.

Exosomes represent a subtype of extracellular vesicle that is released through retrograde transport and fusion of multivesicular bodies with the plasma membrane1. Although no perfect methodologies currently exist for the high-throughput, unbiased isolation of pure plasma exosomes2,3, investigation of exosome-enriched plasma fractions of extracellular vesicles can confer a glimpse into the endocytic pathway on a systems level. Here we conduct high-coverage lipidomics with an emphasis on sterols and oxysterols, and proteomic analyses of exosome-enriched extracellular vesicles (EVs hereafter) from patients at different temporal stages of COVID-19, including the presymptomatic, hyperinflammatory, resolution and convalescent phases. Our study highlights dysregulated raft lipid metabolism that underlies changes in EV lipid membrane anisotropy that alter the exosomal localization of presenilin-1 (PS-1) in the hyperinflammatory phase. We also show in vitro that EVs from different temporal phases trigger distinct metabolic and transcriptional responses in recipient cells, including in alveolar epithelial cells, which denote the primary site of infection, and liver hepatocytes, which represent a distal secondary site. In comparison to the hyperinflammatory phase, EVs from the resolution phase induce opposing effects on eukaryotic translation and Notch signalling. Our results provide insights into cellular lipid metabolism and inter-tissue crosstalk at different stages of COVID-19 and are a resource to increase our understanding of metabolic dysregulation in COVID-19.

Patient hematology during hospitalization for viral pneumonia caused by SARS-CoV-2 and non-SARS-CoV-2 agents: a retrospective study.

BACKGROUND: Hematological comparison of coronavirus disease (COVID-19) and other viral pneumonias can provide insights into COVID-19 treatment. METHODS: In this retrospective case-control single-center study, we compared the data of 126 patients with viral pneumonia during different outbreaks [severe acute respiratory syndrome (SARS) in 2003, influenza A (H1N1) in 2009, human adenovirus type 7 in 2018, and COVID-19 in 2020]. RESULTS: One of the COVID-19 characteristics was a continuous decline in the hemoglobin level. The neutrophil count was related to the aggravation of COVID-19 and SARS. Thrombocytopenia occurred in patients with SARS and severe COVID-19 even at the recovery stage. Lymphocytes were related to the entire course of adenovirus infection, recovery of COVID-19, and disease development of SARS. CONCLUSIONS: Dynamic changes in hematological counts could provide a reference for the pathogenesis and prognosis of pneumonia caused by respiratory viruses in clinics.

Control strategies for COVID-19 epidemic with vaccination, shield immunity and quarantine: A metric temporal logic approach.

Ever since the outbreak of the COVID-19 epidemic, various public health control strategies have been proposed and tested against the coronavirus SARS-CoV-2. We study three specific COVID-19 epidemic control models: the susceptible, exposed, infectious, recovered (SEIR) model with vaccination control; the SEIR model with shield immunity control; and the susceptible, un-quarantined infected, quarantined infected, confirmed infected (SUQC) model with quarantine control. We express the control requirement in metric temporal logic (MTL) formulas (a type of formal specification languages) which can specify the expected control outcomes such as "the deaths from the infection should never exceed one thousand per day within the next three months" or "the population immune from the disease should eventually exceed 200 thousand within the next 100 to 120 days". We then develop methods for synthesizing control strategies with MTL specifications. To the best of our knowledge, this is the first paper to systematically synthesize control strategies based on the COVID-19 epidemic models with formal specifications. We provide simulation results in three different case studies: vaccination control for the COVID-19 epidemic with model parameters estimated from data in Lombardy, Italy; shield immunity control for the COVID-19 epidemic with model parameters estimated from data in Lombardy, Italy; and quarantine control for the COVID-19 epidemic with model parameters estimated from data in Wuhan, China. The results show that the proposed synthesis approach can generate control inputs such that the time-varying numbers of individuals in each category (e.g., infectious, immune) satisfy the MTL specifications. The results also show that early intervention is essential in mitigating the spread of COVID-19, and more control effort is needed for more stringent MTL specifications. For example, based on the model in Lombardy, Italy, achieving less than 100 deaths per day and 10000 total deaths within 100 days requires 441.7% more vaccination control effort than achieving less than 1000 deaths per day and 50000 total deaths within 100 days.

Effect of human umbilical cord-derived mesenchymal stem cells on lung damage in severe COVID-19 patients: a randomized, double-blind, placebo-controlled phase 2 trial.

Treatment of severe Coronavirus Disease 2019 (COVID-19) is challenging. We performed a phase 2 trial to assess the efficacy and safety of human umbilical cord-mesenchymal stem cells (UC-MSCs) to treat severe COVID-19 patients with lung damage, based on our phase 1 data. In this randomized, double-blind, and placebo-controlled trial, we recruited 101 severe COVID-19 patients with lung damage. They were randomly assigned at a 2:1 ratio to receive either UC-MSCs (4 × 107 cells per infusion) or placebo on day 0, 3, and 6. The primary endpoint was an altered proportion of whole lung lesion volumes from baseline to day 28. Other imaging outcomes, 6-minute walk test (6-MWT), maximum vital capacity, diffusing capacity, and adverse events were recorded and analyzed. In all, 100 COVID-19 patients were finally received either UC-MSCs (n = 65) or placebo (n = 35). UC-MSCs administration exerted numerical improvement in whole lung lesion volume from baseline to day 28 compared with the placebo (the median difference was -13.31%, 95% CI -29.14%, 2.13%, P = 0.080). UC-MSCs significantly reduced the proportions of solid component lesion volume compared with the placebo (median difference: -15.45%; 95% CI -30.82%, -0.39%; P = 0.043). The 6-MWT showed an increased distance in patients treated with UC-MSCs (difference: 27.00 m; 95% CI 0.00, 57.00; P = 0.057). The incidence of adverse events was similar in the two groups. These results suggest that UC-MSCs treatment is a safe and potentially effective therapeutic approach for COVID-19 patients with lung damage. A phase 3 trial is required to evaluate effects on reducing mortality and preventing long-term pulmonary disability. (Funded by The National Key R&D Program of China and others. ClinicalTrials.gov number, NCT04288102.

Increased circulating level of interleukin-6 and CD8+ T cell exhaustion are associated with progression of COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is pandemic. It is critical to identify COVID-19 patients who are most likely to develop a severe disease. This study was designed to determine the clinical and epidemiological features of COVID-19 patients associated with the development of pneumonia and factors associated with disease progression. METHODS: Seventy consecutive patients with etiologically confirmed COVID-19 admitted to PLA General Hospital in Beijing, China from December 27, 2019 to March 12, 2020 were enrolled in this study and followed-up to March 16, 2020. Differences in clinical and laboratory findings between COVID-19 patients with pneumonia and those without were determined by the χ2 test or the Fisher exact test (categorical variables) and independent group t test or Mann-Whitney U test (continuous variables). The Cox proportional hazard model and Generalized Estimating Equations were applied to evaluate factors that predicted the progression of COVID-19. RESULTS: The mean incubation was 8.67 (95% confidence interval, 6.78-10.56) days. Mean duration from the first test severe acute respiratory syndrome coronavirus 2-positive to conversion was 11.38 (9.86-12.90) days. Compared to pneumonia-free patients, pneumonia patients were 16.5 years older and had higher frequencies of having hypertension, fever, and cough and higher circulating levels of neutrophil proportion, interleukin-6, low count (< 190/µl) of CD8+ T cells, and neutrophil/lymphocyte ratio. Thirteen patients deteriorated during hospitalization. Cox regression analysis indicated that older age and higher serum levels of interleukin-6, C-reactive protein, procalcitonin, and lactate at admission significantly predicted the progression of COVID-19. During hospitalization, circulating counts of T lymphocytes, CD4+ T cells, and CD8+ T cells were lower, whereas neutrophil proportion, neutrophil/lymphocyte ratio, and the circulating levels of interleukin-6, C-reactive protein, and procalcitonin were higher, in pneumonia patients than in pneumonia-free patients. CD8+ lymphocyte count in pneumonia patients did not recover when discharged. CONCLUSIONS: Older age and higher levels of C-reactive protein, procalcitionin, interleukin-6, and lactate might predict COVID-19 progression. T lymphocyte, especially CD8+ cell-mediated immunity is critical in recovery of COVID-19. This study may help in predicting disease progression and designing immunotherapy for COVID-19.

Human umbilical cord-derived mesenchymal stem cell therapy in patients with COVID-19: a phase 1 clinical trial.

No effective drug treatments are available for coronavirus disease 2019 (COVID-19). Host-directed therapies targeting the underlying aberrant immune responses leading to pulmonary tissue damage, death, or long-term functional disability in survivors require clinical evaluation. We performed a parallel assigned controlled, non-randomized, phase 1 clinical trial to evaluate the safety of human umbilical cord-derived mesenchymal stem cells (UC-MSCs) infusions in the treatment of patients with moderate and severe COVID-19 pulmonary disease. The study enrolled 18 hospitalized patients with COVID-19 (n = 9 for each group). The treatment group received three cycles of intravenous infusion of UC-MSCs (3 × 107 cells per infusion) on days 0, 3, and 6. Both groups received standard COVID-treatment regimens. Adverse events, duration of clinical symptoms, laboratory parameters, length of hospitalization, serial chest computed tomography (CT) images, the PaO2/FiO2 ratio, dynamics of cytokines, and IgG and IgM anti-SARS-CoV-2 antibodies were analyzed. No serious UC-MSCs infusion-associated adverse events were observed. Two patients receiving UC-MSCs developed transient facial flushing and fever, and one patient developed transient hypoxia at 12 h post UC-MSCs transfusion. Mechanical ventilation was required in one patient in the treatment group compared with four in the control group. All patients recovered and were discharged. Our data show that intravenous UC-MSCs infusion in patients with moderate and severe COVID-19 is safe and well tolerated. Phase 2/3 randomized, controlled, double-blinded trials with long-term follow-up are needed to evaluate the therapeutic use of UC-MSCs to reduce deaths and improve long-term treatment outcomes in patients with serious COVID-19.

Single-cell landscape of immunological responses in patients with COVID-19.

In coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the relationship between disease severity and the host immune response is not fully understood. Here we performed single-cell RNA sequencing in peripheral blood samples of 5 healthy donors and 13 patients with COVID-19, including moderate, severe and convalescent cases. Through determining the transcriptional profiles of immune cells, coupled with assembled T cell receptor and B cell receptor sequences, we analyzed the functional properties of immune cells. Most cell types in patients with COVID-19 showed a strong interferon-α response and an overall acute inflammatory response. Moreover, intensive expansion of highly cytotoxic effector T cell subsets, such as CD4+ effector-GNLY (granulysin), CD8+ effector-GNLY and NKT CD160, was associated with convalescence in moderate patients. In severe patients, the immune landscape featured a deranged interferon response, profound immune exhaustion with skewed T cell receptor repertoire and broad T cell expansion. These findings illustrate the dynamic nature of immune responses during disease progression.