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.

Clinical and bacteriological features and prognosis of ascitic fluid infection in Chinese patients with cirrhosis.

BACKGROUND: Spontaneous bacterial peritonitis (SBP) and bacterascites (BA) represent frequent and serious complications in cirrhosis patients with ascites. However, few detailed data are available regarding the clinical and bacteriological feature of SBP or BA patients in China. METHODS: We retrospectively analyzed bacteriological and clinical characteristics of patients with SBP and BA at Beijing 302 Hospital in China from January 2012 to December 2015. RESULTS: A total of 600 patients with SBP (n = 408) or BA (n = 192) were enrolled. Patients with BA appeared to have a less severe clinical manifestation and lower mortality rate than patients with SBP. Gram-negative bacteria formed the majority of pathogens in SBP (73.9%) and BA (55.8%) cases. Higher ascitic fluid polymorphonuclear leucocytes (PMN) count and hepatocellular carcinoma were independent risk factors for BA episode progressing to SBP. The concentration of blood urea nitrogen (BUN) was independent risk factor for 30-day mortality of BA patients. For patients with SBP, the independent risk factors for 30-day mortality were age, Model for End-Stage Liver Disease (MELD) score, septic shock and hepatocellular carcinoma. Patients with third-generation cephalosporin or carbapenems resistant infection had a significantly lower survival probability. There were significant differences in clinical characteristics and outcome among the major bacteria. Multivariate analysis showed that patients infected with Klebsiella spp. had higher hazard ratio of 30-day mortality. CONCLUSION: Our study reported the bacteriological and clinical characteristics of patients with SBP and BA. Higher ascitic fluid PMN count and hepatocellular carcinoma were found to be independent risk factors for BA episode progressed to SBP. Outcome of ascitic fluid infection in patients with cirrhosis was influenced by the type of bacteria and antimicrobial susceptibility.

The small auxin-up RNA OsSAUR45 affects auxin synthesis and transport in rice.

KEY MESSAGE: This research is the first to demonstrate that OsSAUR45 is involved in plant growth though affecting auxin synthesis and transport by repressing OsYUCCA and OsPIN gene expression in rice. Small auxin-up RNAs (SAURs) comprise a large multigene family and are rapidly activated as part of the primary auxin response in plants. However, little is known about the role of SAURs in plant growth and development, especially in monocots. Here, we report the biological function of OsSAUR45 in the model plant rice (Oryza sativa). OsSAUR45 is expressed in a tissue-specific pattern and is localized to the cytoplasm. Rice lines overexpressing OsSAUR45 displayed pleiotropic developmental defects including reduced plant height and primary root length, fewer adventitious roots, narrower leaves, and reduced seed setting. Auxin levels and transport were reduced in the OsSAUR45 overexpression lines, potentially because of decreased expression of Flavin-binding monooxygenase family proteins (OsYUCCAs) and PIN-FORMED family proteins (OsPINs). Exogenous auxin application rapidly induced OsSAUR45 expression and partially restored the phenotype of rice lines overexpressing OsSAUR45. These results demonstrate that OsSAUR45 is involved in plant growth by affecting auxin synthesis and transport through the repression of OsYUCCA and OsPIN gene expression in rice.

Higher viral load and genetic diversity of HIV-1 in seminal compartments than in blood of seven Chinese men who have sex with men and have early HIV-1 infection.

To date, there have been no reports characterizing HIV-1 in the semen of Chinese men who have sex with men (MSM) with early infection. In this study, genetic diversity and viral load of HIV-1 in the seminal compartments and blood of Chinese MSM with early HIV-1 infection were examined. Viral load and genetic diversity of HIV-1 in paired samples of semen and blood were analyzed in seven MSM with early HIV-1 infection. HIV-1 RNA and DNA were quantitated by real-time PCR assays. Through sequencing the C2-V5 region of the HIV-1 env gene, the HIV-1 genotype and genetic diversity based on V3 loop amino acid sequences were determined by using Geno2pheno and PSSM programs co-receptor usage. It was found that there was more HIV-1 RNA in seminal plasma than in blood plasma and total, and more 2-LTR circular and integrated HIV-1 DNA in seminal cells than in peripheral blood mononuclear cells from all seven patients with early HIV-infection. There was also greater HIV-1 genetic diversity in seminal than in blood compartments. HIV-1 in plasma displayed higher genetic diversity than in cells from the blood and semen. In addition, V3 loop central motifs, which present some key neutralizing antibody epitopes, varied between blood and semen. Thus, virological characteristics in semen may be more representative when evaluating risk of transmission in persons with early HIV infection.

Enhanced therapeutic efficacy of combined use of sorafenib and transcatheter arterial chemoembolization for treatment of advanced hepatocellular carcinoma.

OBJECTIVE: Clinical trials suggest that combining transcatheter arterial chemoembolization with sorafenib in patients with advanced hepatocellular carcinoma shows a superior safety and tolerability profile. Our study aimed to retrospectively analyze the utility and prognostic factors of this combined therapy in these patients. METHODS: Patients with advanced hepatocellular carcinoma, treated by transcatheter arterial chemoembolization and sorafenib subsequently, between February 2010 and September 2012 in our hospital, were retrospectively analyzed. After sorafenib treatment for 12 weeks, abdominal enhanced computed tomography or magnetic resonance imaging was used to evaluate short-term outcomes and clinical benefit rate. Overall survival and adverse events were recorded during follow-up. Univariate and multivariate analyses were used to identify relationships between baseline characteristics and overall survival. RESULTS: Fifty-one advanced hepatocellular carcinoma patients were included. Common adverse events for sorafenib were hand-foot skin reaction, alopecia, diarrhea, anorexia and fatigue. The clinical benefit rate was 64% and the median survival time was 7.5 months. Median survival of patients with and without portal vein tumor thrombi was 6.0 months and 10.3 months (P < 0.001), respectively. Median survival of patients with cholinesterase ≥5000 U/l and < 5000 U/l was 10.6 months and 6.1 months (P < 0.001), respectively. Multivariate analysis identified the presence of portal vein tumor thrombi and low cholinesterase level as independent negative predictors of survival. CONCLUSIONS: Combining sorafenib and transcatheter arterial chemoembolization was safe and effective for advanced hepatocellular carcinoma patients with extrahepatic spread but without portal vein tumor thrombi. Portal vein tumor thrombi and cholinesterase level are independent predictors of prognosis following this combined therapy.

[Clinical manifestation and autoantibody profile in 123 patients with primary biliary cirrhosis].

OBJECTIVE: To investigate the autoantibody profile and its clinical implication in the patients with primary biliary cirrhosis. METHODS: During the period of 2008 to 2010,123 patients with primary biliary cirrhosis (PBC) in our hospital were enrolled in this study, of whom, 70 patients were with cirrhosis and 53 without cirrhosis, The autoantibody profile was tested for each patient by using immunoblotting and indirect immunofluorescence. RESULTS: Of the 123 PBC patients with liver cirrhosis, 49% were positive with serum ANA positive; 47%, 51%, 54%, 31% and 49% were positive with serum anti-nuclear antibodies (ANA), anti-mitochondrial antibodies-M2 (AMA-M2), anti-promyelocytic leukemia (anti-PML), anti-sp100 antibodies (anti-sp100), anti-Ro-52 antibody (anti-52KD), respectively. By contrast, of the PBC patients without liver cirrhosis, only 38%, 37%, 51%, 60%, 30% and 51% were positive with serum ANA, AMA, AMA-M2, anti-PML, anti-sp100 and anti-52KD, respectively.There was the statistical difference between the two groups. In addition, it was also found that the anti-gp210 antibody positive group had a higher Mayo risk score,lower serum albumin and severe cholestasis and impaired liver function when compared with anti-gp210 antibody negative patients. CONCLUSION: Our data indicate that serum AMA is helpful for early diagnosis of PBC, and in particular, serum ANA positivity can help make a diagnosis for the AMA-negative patients. These indicate that anti-gp210 antibodies appear in the late course of PBC.Anti-gp210 positive PBC patients have more severe cholestasis and liver dysfunction.

[A clinical and pathological analysis of 22 cases of primary sclerosing cholangitis].

OBJECTIVE: To characterize the clinical, laboratory, imaging and pathological features of primary sclerosing cholangitis (PSC) and investigate the impact of ursodeoxycholic acid (UDCA) therapy on patient prognosis. METHODS: The medical records of 22 patients diagnosed with PSC between 2002 and 2011 were retrospectively reviewed. The PSC diagnosis had been made in patients with suspect biochemical abnormalities following evaluation by magnetic resonance cholangiopancreatography (MRCP) and/or endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC). Fibrosis and inflammation were assessed by immunohistochemical analyses of tissue biopsies. Outcome of patients treated with UDCA (13-15 mg/kg/day, oral) were compared to that of patients without UDCA treatment by the X2 or corrected X2 tests. RESULTS: Among the 22 PSC patients, the majority was male (n=15) and presented with fatigue, dark urine, and body weight loss (n=15). Four cases had ulcerative colitis. At admission, all 22 cases showed elevated levels of alkaline phosphatase[ALP: (348+/-184) U/L], 19 cases showed elevated alanine aminotransferase [ALT: (94.0+/-67.0) U/L] and aspartate aminotransferase [AST: (98.0+/-67.0) U/L], and 15 cases showed elevated levels of total bilirubin (99.0+/-115.0) mumol/L and direct bilirubin (74.4+/-92.4 mumol/L. ERCP examination showed segmental intrahepatic bile duct stenosis with expansion, and stiff and enlarged gallbladder bile ducts, but unclear findings for the common bile ducts and pancreatic ducts. MRCP showed beading of the intrahepatic bile duct, stiffness of the bile duct wall, and dilation of the common bile duct. Fibrosis and inflammation were observed in the bile ducts, along with hyperplasia and the typical features of "onion skin" fibrosis and fibrous obliterative cholangitis. Five of the 10 patients treated with UDCA improved, and seven of the 12 patients in the non-UDCA treatment group improved. There was no statistically significant difference in outcome between the groups (paired X2=0.333, corrected X2=0.083, P more than 0.05). CONCLUSION: PSC patients were predominantly male and the common clinical manifestations were fatigue, dark urine, and body weight loss. At admission, serum biochemical indicators of cholangitis were increased significantly and subsequent imaging studies confirmed the suspected diagnosis by showing obvious characteristic changes. UDCA treatment did not significantly improve patient prognosis.

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).

[Prospective controlled trial of safety of human umbilical cord derived-mesenchymal stem cell transplantation in patients with decompensated liver cirrhosis].

OBJECTIVE: To evaluate the safety of human umbilical cord derived-mesenchymal stem cell (UC-MSC) transplantation therapy in patients with decompensated liver cirrhosis. METHODS: UC-MSCs were transplanted intravenously into patients with decompensated liver cirrhosis. Serum levels of glucose (GLU), total cholesterol (TC), blood urea nitrogen (BUN), alpha fetoprotein (AFP), white blood cells (WBC), and prothrombin activity (PA) were detected at different time points after UC-MSCs transplantation. RESULTS: Most UC-MSC transplanted patients experienced an improvement in quality of life, to varying degrees. With the exception of low-grade fever in a few patients, side effects and oncogenic events were rare (treatment group: 1/38 vs. control group: 1/16; P more than 0.05). The UC-MSCs transplantation showed no effect on GLU, TC, BUN, AFP, WBC, or PA. CONCLUSION: UC-MSCs transplantation in patients with decompensated liver cirrhosis is safe and may improve the patient's quality of life.

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.

Interleukin-17-producing CD4(+) T cells increase with severity of liver damage in patients with chronic hepatitis B.

UNLABELLED: Interleukin-17 (IL-17)-producing CD4(+) T cells (Th17)-mediated immune response has been demonstrated to play a critical role in inflammation-associated disease; however, its role in chronic hepatitis B virus (HBV) infection remains unknown. Here we characterized peripheral and intrahepatic Th17 cells and analyzed their association with liver injury in a cohort of HBV-infected patients including 66 with chronic hepatitis B (CHB), 23 with HBV-associated acute-on-chronic liver failure (ACLF), and 30 healthy subjects as controls. The frequency of circulating Th17 cells increased with disease progression from CHB (mean, 4.34%) to ACLF (mean, 5.62%) patients versus healthy controls (mean, 2.42%). Th17 cells were also found to be largely accumulated in the livers of CHB patients. The increases in circulating and intrahepatic Th17 cells positively correlated with plasma viral load, serum alanine aminotransferase levels, and histological activity index. In vitro, IL-17 can promote the activation of myeloid dendritic cells and monocytes and enhance the capacity to produce proinflammatory cytokines IL-1beta, IL-6, tumor necrosis factor (TNF)-alpha, and IL-23 in both CHB patients and healthy subjects. In addition, the concentration of serum Th17-associated cytokines was also increased in CHB and ACLF patients. CONCLUSION: Th17 cells are highly enriched in both peripheral blood and liver of CHB patients, and exhibit a potential to exacerbate liver damage during chronic HBV infection.

Mesenchymal stem cell therapy in decompensated liver cirrhosis: a long-term follow-up analysis of the randomized controlled clinical trial.

BACKGROUND: Mesenchymal stem cell (MSC) infusion was reported to improve liver function in patients with decompensated liver cirrhosis (DLC); however, whether the medication can improve outcome of these patients is poorly understood. METHODS: This prospective, open-labeled, randomized controlled study enrolled 219 patients with HBV-related DLC who were divided into control group (n = 111) and umbilical cord-derived MSC (UC-MSC)-treated group (n = 108), then all of them received a follow-up check from October 2010 to October 2017. The treated patients received three times of UC-MSC infusions at 4-week intervals plus conventional treatment that was only used for control group. The overall survival rate and HCC-free survival rate were calculated as primary endpoints and the liver function and adverse events associated with the medication were also evaluated. RESULTS: During the follow-up check period from 13 to 75th months, there was a significantly higher overall survival rate in the treated group than the control group, while the difference of the hepatocellular carcinoma event-free survival rate between the treated and control groups was not observed during the 75-month follow-up. UC-MSC treatment markedly improved liver function, as indicated by the levels of serum albumin, prothrombin activity, cholinesterase, and total bilirubin during 48 weeks of follow-up. No significant side effects or treatment-related complications were observed in the UC-MSC group. CONCLUSIONS: Therapy of UC-MSC is not only well tolerated, but also significantly improves long-term survival rate, as well as the liver function in patients with HBV-related DLC. UC-MSC medication, therefore, might present a novel therapeutic approach for the disease.

Immunotherapy of HBV-related advanced hepatocellular carcinoma with short-term HBV-specific TCR expressed T cells: results of dose escalation, phase I trial.

BACKGROUND & AIMS: Immunotherapy with hepatitis B virus (HBV)-specific TCR redirected T (HBV-TCR-T) cells in HBV-related hepatocellular carcinoma (HBV-HCC) patients after liver transplantation was reported to be safe and had potential therapeutic efficacy. We aim to investigate the safety of HBV-TCR-T-cell immunotherapy in advanced HBV-HCC patients who had not met the criteria for liver transplantation. METHODS: We enrolled eight patients with advanced HBV-HCC and adoptively transferred short-lived autologous T cells expressing HBV-specific TCR to perform an open-label, phase 1 dose-escalation study (NCT03899415). The primary endpoint was to evaluate the safety of HBV-TCR-T-cell therapy according to National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.03) during the dose-escalation process. The secondary endpoint was to assess the efficacy of HBV-TCR-T-cell therapy by evaluating the anti-tumor responses using RECIST criteria (version 1.1) and the overall survival. RESULTS: Adverse events were observed in two participants among the 8 patients enrolled. Only one patient experienced a Grade 3 liver-related adverse event after receiving a dose of 1 × 105 HBV-TCR-T cells/kg, then normalized without interventions with immunosuppressive agents. Among the patients, one achieved a partial response lasting for 27.7 months. Importantly, most of the patients exhibited a reduction or stabilization of circulating HBsAg and HBV DNA levels after HBV-TCR-T-cell infusion, indicating the on-target effects. CONCLUSIONS: The adoptive transfer of HBV-TCR-T cells into advanced HBV-HCC patients were generally safe and well-tolerated. Observations of clinical efficacy support the continued development and eventual application of this treatment strategy in patients with advanced HBV-related HCC. CLINICAL TRIALS REGISTRATION: This study was registered at ClinicalTrials.gov (NCT03899415).

Systematic Discovery and Pathway Analyses of Metabolic Disturbance in COVID-19.

Background: The ongoing global coronavirus disease 2019 (COVID-19) pandemic is posing a serious public health threat to nations worldwide. Understanding the pathogenesis of the disease and host immune responses will facilitate the discovery of therapeutic targets and better management of infected patients. Metabolomics technology can provide an unbiased tool to explore metabolic perturbation. Methods: Twenty-six healthy controls and 50 COVID-19 patients with mild, moderate, and severe symptoms in the Fifth Medical Center of PLA General Hospital from January 22 to February 16, 2020 were recruited into the study. Fasting blood samples were collected and subject to metabolomics analysis by liquid chromatography-mass spectrometry. Metabolite abundance was measured by peak area and was log-transformed before statistical analysis. The principal component analysis, different expression analysis, and metabolic pathway analysis were performed using R package. Co-regulated metabolites and their associations with clinical indices were identified by the weighted correlation network analysis and Spearman correlation coefficients. The potential metabolite biomarkers were analyzed using a random forest model. Results: We uncovered over 100 metabolites that were associated with COVID-19 disease and many of them correlated with disease severity. Sets of highly correlated metabolites were identified and their correlations with clinical indices were presented. Further analyses linked the differential metabolites with biochemical reactions, metabolic pathways, and biomedical MeSH terms, offering contextual insights into disease pathogenesis and host responses. Finally, a panel of metabolites was discovered to be able to discriminate COVID-19 patients from healthy controls, and also another list for mild against more severe cases. Our findings showed that in COVID-19 patients, citrate cycle, sphingosine 1-phosphate in sphingolipid metabolism, and steroid hormone biosynthesis were downregulated, while purine metabolism and tryptophan metabolism were disturbed. Conclusion: This study discovered key metabolites as well as their related biological and medical concepts pertaining to COVID-19 pathogenesis and host immune response, which will facilitate the selection of potential biomarkers for prognosis and discovery of therapeutic targets.

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.

Progressive CD127 down-regulation correlates with increased apoptosis of CD8 T cells during chronic HIV-1 infection.

Chronic HIV-1 infection can induce a significant decrease in CD127 expression on CD8 T cells, but the underlying mechanisms and immunological consequences are unclear. In this study, we investigated CD127 expression on CD8 T cells from a total of 51 HIV-1-infected subjects and 16 healthy individuals and analyzed the association between CD127 expression and CD8 T-cell apoptosis in these HIV-1-infected subjects. We found that CD127 expression on total CD8 T cells was significantly down-regulated, which was correlated with the increased CD8 T-cell apoptosis and disease progression of chronic HIV-1 infection. The in vitro addition of IL-7 efficiently rescued the spontaneous apoptosis of CD8 T cells from HIV-1-infected individuals. IL-7 stimulation also transiently down-regulated CD127 expression, whereas some of the CD127(-) CD8 T cells regained CD127 expression soon after IL-7 was retracted from the incubation medium. Thus, IL-7 stimulation reduced apoptosis of both CD127(+) and CD127(-)CD8 T cells to some degree. These data indicate that CD127 loss might impair IL-7 signaling and increase CD8 T-cell apoptosis during HIV-1 infection. This study, therefore, will extend the notion that IL-7 could be a good candidate for immunotherapy in HIV-1-infected patients.

Cutting edge: programmed death-1 up-regulation is involved in the attrition of cytomegalovirus-specific CD8+ T cells in acute self-limited hepatitis B virus infection.

Attrition of heterologous virus-specific CD8(+) T cells has been demonstrated in murine viral infection; however, little is known regarding this phenomenon in human viral infections. In this study, we observed that CMV-specific CD8(+) T cells displayed numerical decline and functional impairment in the early phase of acute infection, whereas programmed death-1 (PD-1) expression was significantly up-regulated by these CMV-specific CD8(+) T cells. This early PD-1 up-regulation was found to be closely associated with the increased apoptotic sensitivity of CMV-specific CD8(+) T cells. The in vitro addition of anti-PD-1 further enhanced the spontaneous apoptosis of CMV-specific CD8(+) T cells; however, blockade of the PD-1-mediated pathway with anti-PD-L1 significantly restored the CMV-specific CD8(+) T cell proliferation and IFN-gamma production. Thus, PD-1 plays a crucial role in the attrition of CMV-specific CD8(+) T cells in acute hepatitis B virus infection, which in turn, influences the preexisting homeostatic virus-specific CD8(+) T cell pool.

Omics-Driven Systems Interrogation of Metabolic Dysregulation in COVID-19 Pathogenesis.

The coronavirus disease 2019 (COVID-19) pandemic presents an unprecedented threat to global public health. Herein, we utilized a combination of targeted and untargeted tandem mass spectrometry to analyze the plasma lipidome and metabolome in mild, moderate, and severe COVID-19 patients and healthy controls. A panel of 10 plasma metabolites effectively distinguished COVID-19 patients from healthy controls (AUC = 0.975). Plasma lipidome of COVID-19 resembled that of monosialodihexosyl ganglioside (GM3)-enriched exosomes, with enhanced levels of sphingomyelins (SMs) and GM3s, and reduced diacylglycerols (DAGs). Systems evaluation of metabolic dysregulation in COVID-19 was performed using multiscale embedded differential correlation network analyses. Using exosomes isolated from the same cohort, we demonstrated that exosomes of COVID-19 patients with elevating disease severity were increasingly enriched in GM3s. Our work suggests that GM3-enriched exosomes may partake in pathological processes related to COVID-19 pathogenesis and presents the largest repository on the plasma lipidome and metabolome distinct to COVID-19.

[Immunologically-competent cells in liver infiltrating lymphocytes in patients with chronic severe hepatitis B].

OBJECTIVE: To investigate the frequencies of immunologically competent cells (ICCs) in the liver-infiltrating lymphocytes (LILs) and peripheral blood and their possible role in pathogenesis in patients with chronic severe hepatitis B (CSHB). METHODS: LILs were isolated from the liver tissue samples from 11 CSHB patients and 5 normal controls (NCs) by the method of combined grinding with semi-frosted microscopic slides and sedimentation of hepatic cells. The frequency of isolated ICCs, including CD3(+), CD4(+), and CD8(+) T-cells, NK cells, NKT cells, and B cells was examined and compared with that of the circulating ICCs in the CSHB patients. Comparison was conducted between the CSHB patients and the controls. RESULTS: (1) In the CSHB patients, the frequencies of CD4(+) T cells and B cells in LILs were 17% +/- 6% and 3.0% +/- 1.0% respectively, both significantly lower than those in the circulating blood (32% +/- 8% and 21.4% +/- 12.2% respectively, both P < 0.01); however, the frequencies of CD8(+) T cells, NK cells, and NKT cells in LILs were 38% +/- 13%, 34% +/- 18%, and 10% +/- 4% respectively, all significantly lower than those in the circulating blood (26% +/- 6%, 15% +/- 9%, and 6% +/- 4%, all P < 0.05). (2) The frequencies of infiltrating CD3(+) T cells and CD4(+) T cells of the CSHB patients were both significantly higher than those of the NCs (P = 0.042 and P = 0.001); and the frequency of infiltrating CD8(+) T cells of the CSHB patients was higher than that of the NCs, and the and the frequencies of infiltrating NK cells and NKT cells in LILs were lower than those of the NCs, however, not significantly. (3) Compared with the liver tissues from the NCs, the liver tissues from the CSHB patients exhibited a significantly higher ratio of liver-infiltrating CD4(+) T cells to peripheral blood CD4(+) T-cell subsets (P = 0.001), and significantly lower ratios of liver-infiltrating NKT cells and B cells to the peripheral blood NKT-cells and B cells (P = 0.029 and P = 0.001 respectively). CONCLUSION: The abundant infiltrating immune active cells, especially the CD4(+) T cells, CD8(+) T cells, and NK cells, may be the causal factors that drive the progressive development of CSHB.

A survey of knowledge about hepatitis B among new military recruits in China.

BACKGROUND: Hepatitis B is a disease that affects the liver and is caused by the hepatitis B virus (HBV). Hepatitis B is a serious public health problem in China. The objective of this study was to assess knowledge of and behaviours towards the transmission and prevention of hepatitis B of new military recruits in China. METHODS: A cross-sectional study was conducted among 800 new military recruits. A self-administered, structured questionnaire was used to collect information, and 727 questionnaires were returned completed. Analysis was performed using SPSS 18.0, and P < 0.05 was considered statistically significant. RESULTS: Of the respondents, 665 (91.5%) were male and 62 (8.5%) were female. The mean age was 18.9 ± 1.7 years. A total of 608 respondents (83.6%) demonstrated poor knowledge and 119 (16.4%) adequate knowledge about HBV. Older age, female and higher education level were statistically associated with a higher mean knowledge score. Multivariate logistic regression showed that age (OR = 3.040, 95%CI 1.724-5.359, P < 0.001) and gender (OR = 1.791, 95%CI 1.325-2.421, P < 0.001) were significantly associated with appropriate behavioural practices towards prevention of HBV. CONCLUSION: Against a backdrop of high HBV prevalence in China, new military recruits had poor knowledge of HBV. New recruits need better education about HBV to assist in reducing and preventing HBV infection.