Iridium(III) complex induces apoptosis in HeLa cells by regulating mitochondrial and PI3K/AKT signaling pathways: In vitro and in vivo experiments.

Cyclometalated iridium complexes with mitochondrial targeting show great potential as substitutes for platinum-based complexes because of their strong anti-cancer properties. Three novel cyclometalated iridium(III) compounds were synthesized and evaluated in five different cell lines as part of the ongoing systematic investigations of these compounds. The complexes were prepared using 4,7-dichloro-1,10-phenanthroline ligands. The cytotoxicity of complexes Ir1-Ir3 towards HeLa cells was shown to be high, with IC50 values of 0.83±0.06, 4.73±0.11, and 4.95±0.62 µM, respectively. Complex Ir1 could be ingested by HeLa cells in 3 h and has shown high selectivity toward mitochondria. Subsequent investigations demonstrated that Ir1 triggered apoptosis in HeLa cells by augmenting the generation of reactive oxygen species (ROS), reducing the mitochondrial membrane potential, and depleting ATP levels. Furthermore, the movement of cells was significantly suppressed and the progression of the cell cycle was arrested in the G0/G1 phase following the administration of Ir1. The Western blot analysis demonstrated that the induction of apoptosis in HeLa cells by Ir1 involves the activation of the mitochondria-dependent channel and the PI3K/AKT signaling pathway. No significant cytotoxicity was observed in zebrafish embryos at concentrations less than or equal to 16 µM, e.g., survival rate and developmental abnormalities. In vivo, antitumor assay demonstrated that Ir1 suppressed tumor growth in mice. Therefore, our work shows that complex Ir1 could be a promising candidate for developing novel antitumor drugs.

Prevalence, Characteristics, and Outcomes Associated with Acute Kidney Injury among Adult Patients with Severe Dengue in Mainland China.

Acute kidney injury (AKI) can occur in adult patients with severe dengue (SD) and have serious clinical outcomes. This study aimed to determine the prevalence, characteristics, risk factors, and clinical outcomes of AKI in adult patients with SD; the correlation of dengue virus (DENV) serological and virological profiles with AKI; and the clinical features of patients with severe AKI who received renal replacement treatment (RRT). This multicenter study was conducted in Guangdong Province, China, between January 2013 and November 2019. A total of 242 patients were evaluated, of which 85 (35.1%) developed AKI and 32 (13.2%) developed severe AKI (stage 3). Patients with AKI had a higher fatality rate (22.4% versus 5.7%; P < 0.001) and longer length of hospital stay (median: 13 versus 9 days; P < 0.001). Independent risk factors for AKI were hypertension (odds ratio [OR]: 2.03; 95% CI: 1.10-3.76), use of nephrotoxic drugs (OR: 1.90; 95% CI: 1.00-3.60), respiratory distress (OR: 4.15; 95% CI: 1.787-9.632), high international normalized ratio (INR) levels (OR: 6.44; 95% CI: 1.89-21.95), and hematuria (OR: 2.12; 95% CI: 1.14-3.95). There was no significant association between DENV serological and virological profiles and the presence or absence of AKI. Among patients with severe AKI, those who received RRT had a longer length of hospital stay and similar fatality rate. Hence, adult patients with SD should be closely monitored for the development of AKI to enable timely and appropriate therapy.

Patient-derived monoclonal antibodies to SARS-CoV-2 nucleocapsid protein N-terminal and C-terminal domains cross-react with their counterparts of SARS-CoV, but not other human betacoronaviruses.

Introduction: SARS-CoV-2 nucleocapsid (N) protein plays a key role in multiple stages of the viral life cycle such as viral replication and assembly. This protein is more conserved than the Spike protein of the virus and can induce both humoral and cell-mediated immune responses, thereby becoming a target for clinical diagnosis and vaccine development. However, the immunogenic characteristics of this protein during natural infection are still not completely understood. Methods: Patient-derived monoclonal antibodies (mAbs) against SARS-CoV-2 N protein were generated from memory B cells in the PBMCs using the antigen-specific B cell approach. For epitope mapping of the isolated hmAbs, a panel of series-truncated N proteins were used , which covered the N-terminal domain (NTD, aa 46-174 ) and C-terminal domain (CTD, aa 245-364 ), as well as the flanking regions of NTD and CTD. NTD- or CTD-specific Abs in the plasma from COVID-19 patients were also tested by ELISA method. Cross-binding of hmAbs or plasma Abs in COVID-19 patients to other human ß-CoV N proteins was determined using the capture ELISA. Results: We isolated five N-specific monoclonal antibodies (mAbs) from memory B cells in the peripheral blood of two convalescent COVID-19 patients. Epitope mapping revealed that three of the patient-derived mAbs (N3, N5 and N31) targeted the C-terminal domain (CTD), whereas two of the mAbs (N83 and 3B7) targeted the N-terminal domain (NTD) of SARS-CoV-2 N protein. All five patient-derived mAbs were cross-reactive to the N protein of SARS-CoV but showed little to no cross-reactivity to the N proteins of other human beta coronaviruses (ß-CoVs). We also tested 52 plasma samples collected from convalescent COVID-19 patients for Abs against the N proteins of human ß-CoVs and found that 78.8% of plasma samples showed detectable Abs against the N proteins of SARS-CoV-2 and SARS-CoV. No plasma sample had cross-reactive Abs to the N protein of MERS-CoV. Cross-reactive Abs to the N proteins of OC43 and HKU1 were detected in 36.5% (19/52) and 19.2% (10/52) of plasma samples, respectively. Discussion: These results suggest that natural SARS-CoV-2 infection elicits cross-reactive Abs to the N protein of SARS-CoV and that the five patient-derived mAbs to SARS-CoV-2 N protein NTD and CTD cross-react with their counterparts of SARS-CoV, but not other human ß-CoVs. Thus, these five patient-derived mAbs can potentially be used for developing the next generation of COVID-19 At-Home Test kits for rapid and specific screening of SARS-CoV-2 infection.

COVID-19 induces new-onset insulin resistance and lipid metabolic dysregulation via regulation of secreted metabolic factors.

Abnormal glucose and lipid metabolism in COVID-19 patients were recently reported with unclear mechanism. In this study, we retrospectively investigated a cohort of COVID-19 patients without pre-existing metabolic-related diseases, and found new-onset insulin resistance, hyperglycemia, and decreased HDL-C in these patients. Mechanistically, SARS-CoV-2 infection increased the expression of RE1-silencing transcription factor (REST), which modulated the expression of secreted metabolic factors including myeloperoxidase, apelin, and myostatin at the transcriptional level, resulting in the perturbation of glucose and lipid metabolism. Furthermore, several lipids, including (±)5-HETE, (±)12-HETE, propionic acid, and isobutyric acid were identified as the potential biomarkers of COVID-19-induced metabolic dysregulation, especially in insulin resistance. Taken together, our study revealed insulin resistance as the direct cause of hyperglycemia upon COVID-19, and further illustrated the underlying mechanisms, providing potential therapeutic targets for COVID-19-induced metabolic complications.

Celebrex Adjuvant Therapy on Coronavirus Disease 2019: An Experimental Study.

Background: The pandemic of coronavirus disease 2019 (COVID-19) resulted in grave morbidity and mortality worldwide. There is currently no effective drug to cure COVID-19. Based on analyses of available data, we deduced that excessive prostaglandin E2 (PGE2) produced by cyclooxygenase-2 was a key pathological event of COVID-19. Methods: A prospective clinical study was conducted in one hospital for COVID-19 treatment with Celebrex to suppress the excessive PGE2 production. A total of 44 COVID-19 cases were enrolled, 37 cases in the experimental group received Celebrex as adjuvant (full dose: 0.2 g, bid; half dose: 0.2 g, qd) for 7-14 days, and the dosage and duration was adjusted for individuals, while seven cases in the control group received the standard therapy. The clinical outcomes were evaluated by measuring the urine PGE2 levels, lab tests, CT scans, vital signs, and other clinical data. The urine PGE2 levels were measured by mass spectrometry. The study was registered and can be accessed at http://www.chictr.org.cn/showproj.aspx?proj=50474. Results: The concentrations of PGE2 in urine samples of COVID-19 patients were significantly higher than those of PGE2 in urine samples of healthy individuals (mean value: 170 ng/ml vs 18.8 ng/ml, p < 0.01) and positively correlated with the progression of COVID-19. Among those 37 experimental cases, there were 10 cases with age over 60 years (27%, 10/37) and 13 cases (35%, 13/37) with preexisting conditions including cancer, atherosclerosis, and diabetes. Twenty-five cases had full dose, 11 cases with half dose of Celebrex, and one case with ibuprofen. The remission rates in midterm were 100%, 82%, and 57% of the full dose, half dose, and control group, respectively, and the discharged rate was 100% at the endpoint with Celebrex treatment. Celebrex significantly reduced the PGE2 levels and promoted recovery of ordinary and severe COVID-19. Furthermore, more complications, severity, and death rate were widely observed and reported in the COVID-19 group of elders and with comorbidities; however, this phenomenon did not appear in this particular Celebrex adjunctive treatment study. Conclusion: This clinical study indicates that Celebrex adjuvant treatment promotes the recovery of all types of COVID-19 and further reduces the mortality rate of elderly and those with comorbidities.

Efficacy and Safety of Lopinavir/Ritonavir or Arbidol in Adult Patients with Mild/Moderate COVID-19: An Exploratory Randomized Controlled Trial.

BACKGROUND: Antiviral therapies against the novel coronavirus SARS-CoV-2, which has caused a global pandemic of respiratory illness called COVID-19, are still lacking. METHODS: Our study (ClinicalTrials.gov: NCT04252885, named ELACOI), was an exploratory randomized (2:2:1) controlled trial assessing the efficacy and safety of lopinavir/ritonavir (LPV/r) or arbidol monotherapy for treating patients with mild/moderate COVID-19. FINDINGS: This study successfully enrolled 86 patients with mild/moderate COVID-19, with 34 randomly assigned to receive LPV/r, 35 to arbidol, and 17 with no antiviral medication as control. Baseline characteristics of the three groups were comparable. The primary endpoint, the rate of positive-to-negative conversion of SARS-CoV-2 nucleic acid, was similar between groups (all p > 0.05). There were no differences between groups in the secondary endpoints, the rates of antipyresis, cough alleviation, or improvement of chest computed tomography (CT) at days 7 or 14 (all p > 0.05). At day 7, 8 (23.5%) patients in the LPV/r group, 3 (8.6%) in the arbidol group, and 2 (11.8%) in the control group showed a deterioration in clinical status from moderate to severe/critical (p = 0.206). Overall, 12 (35.3%) patients in the LPV/r group and 5 (14.3%) in the arbidol group experienced adverse events during the follow-up period. No apparent adverse event occurred in the control group. CONCLUSIONS: LPV/r or arbidol monotherapy present little benefit for improving the clinical outcome of patients hospitalized with mild/moderate COVID-19 over supportive care. FUNDING: This study was supported by project 2018ZX10302103-002, 2017ZX10202102-003-004, and Infectious Disease Specialty of Guangzhou High-level Clinical Key Specialty (2019-2021).

Associations of clinical characteristics and treatment regimens with the duration of viral RNA shedding in patients with COVID-19.

OBJECTIVE: The novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic, but the factors influencing viral RNA shedding, which would help inform optimal control strategies, remain unclear. METHODS: The clinical course and viral RNA shedding pattern of 267 consecutive symptomatic COVID-19 patients admitted to the hospital from January 20, 2020 to March 15, 2020 were evaluated retrospectively. RESULTS: The median duration of viral RNA shedding was 12 days (interquartile range 8-16 days) after the onset of illness. Of the 267 patients included in this study, 65.2% had viral RNA clearance within 14 days, 88.8% within 21 days, and 94.4% within 28 days. Older age (hazard ratio (HR) 0.99, 95% confidence interval (CI) 0.98-1.00; p = 0.04), time lag from illness onset to hospital admission (HR 0.91, 95% CI 0.88-0.94; p < 0.001), diarrhea (HR 0.59, 95% CI 0.36-0.96; p = 0.036), corticosteroid treatment (HR 0.60, 95% CI 0.39-0.94; p = 0.024), and lopinavir/ritonavir use (HR 0.70, 95% CI 0.52-0.94; p = 0.014) were significantly and independently associated with prolonged viral RNA shedding. CONCLUSIONS: Early detection and timely hospital admission may be warranted for symptomatic COVID-19 patients, especially for older patients and patients with diarrhea. Corticosteroid treatment is associated with prolonged viral RNA shedding and should be used with caution. Lopinavir/ritonavir use may be associated with prolonged viral RNA shedding in non-severe patients; further randomized controlled trials are needed to confirm this finding.

Clinical Characteristics of Patients Infected With the Novel 2019 Coronavirus (SARS-Cov-2) in Guangzhou, China.

BACKGROUND: The clinical manifestations and factors associated with the severity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections outside of Wuhan are not clearly understood. METHODS: All laboratory-confirmed cases with SARS-Cov-2 infection who were hospitalized and monitored in Guangzhou Eighth People's Hospital were recruited from January 20 to February 10. RESULTS: A total of 275 patients were included in this study. The median patient age was 49 years, and 63.6% had exposure to Wuhan. The median virus incubation period was 6 days. Fever (70.5%) and dry cough (56.0%) were the most common symptoms. A decreased albumin level was found in 51.3% of patients, lymphopenia in 33.5%, and pneumonia based on chest computed tomography in 86%. Approximately 16% of patients (n = 45) had severe disease, and there were no deaths. Compared with patients with nonsevere disease, those with severe disease were older, had a higher frequency of coexisting conditions and pneumonia, and had a shorter incubation period (all P < .05). There were no differences between patients who likely contacted the virus in Wuhan and those who had no exposure to Wuhan. Multivariate logistic regression analysis indicated that older age, male sex, and decreased albumin level were independently associated with disease severity. CONCLUSIONS: Most of the patients infected with SARS-CoV-2 in Guangzhou, China are not severe cases and patients with older age, male, and decreased albumin level were more likely to develop into severe ones.

Preliminary evidence from a multicenter prospective observational study of the safety and efficacy of chloroquine for the treatment of COVID-19.

Effective therapies are urgently needed for the SARS-CoV-2 pandemic. Chloroquine has been proved to have antiviral effect against coronavirus in vitro. In this study, we aimed to assess the efficacy and safety of chloroquine with different doses in COVID-19. In this multicenter prospective observational study, we enrolled patients older than 18 years old with confirmed SARS-CoV-2 infection excluding critical cases from 12 hospitals in Guangdong and Hubei Provinces. Eligible patients received chloroquine phosphate 500 mg, orally, once (half dose) or twice (full dose) daily. Patients treated with non-chloroquine therapy were included as historical controls. The primary endpoint is the time to undetectable viral RNA. Secondary outcomes include the proportion of patients with undetectable viral RNA by day 10 and 14, hospitalization time, duration of fever, and adverse events. A total of 197 patients completed chloroquine treatment, and 176 patients were included as historical controls. The median time to achieve an undetectable viral RNA was shorter in chloroquine than in non-chloroquine (absolute difference in medians -6.0 days; 95% CI -6.0 to -4.0). The duration of fever is shorter in chloroquine (geometric mean ratio 0.6; 95% CI 0.5 to 0.8). No serious adverse events were observed in the chloroquine group. Patients treated with half dose experienced lower rate of adverse events than with full dose. Although randomized trials are needed for further evaluation, this study provides evidence for safety and efficacy of chloroquine in COVID-19 and suggests that chloroquine can be a cost-effective therapy for combating the COVID-19 pandemic.

Gemykibivirus Genome in Lower Respiratory Tract of Elderly Woman With Unexplained Acute Respiratory Distress Syndrome.

Using metagenomics analysis, we are the first to identify the presence of a small, circular, single-stranded Gemykibivirus (GkV) genome from the respiratory tract of an elderly woman with severe acute respiratory distress syndrome. Our results suggest that further studies on whether GkVs infect humans and cause respiratory disease are needed.

Kinetics of antigen-specific IgM/IgG/IgA antibody responses during Zika virus natural infection in two patients.

Understanding of kinetics of antibody responses is crucial for developing rapid serological tests and studying the mechanisms of Zika virus (ZIKV) infection. Most of the serological diagnostic assays previously published are based on either IgM or IgG titer, little is known on the level of IgA antibody in saliva and urine. In this study, we investigated the kinetics of IgM/IgG/IgA antibody responses in serum, saliva, and urine obtained from two ZIKV infected individuals from as early as the second day of onset of symptoms to as long as 2 years postinfection. Other than detecting robust early IgM response, long lasting IgG response, we discovered strong early IgA response specific for ZIKV in saliva in both patients. This unique observation provides a novel strategy and scientific basis for the development of noninvasive rapid tests for ZIKV infection.

Dengue immune sera enhance Zika virus infection in human peripheral blood monocytes through Fc gamma receptors.

Antibody dependent enhancement (ADE) has most often been associated with dengue virus (DENV). Studies using leukemia cell lines suggest that DENV specific antibodies can enhance Zika virus (ZIKV) infectivity, and vice versa. To examine the mechanisms of ADE of ZIKV infection in primary human cells, we assessed 40 serum samples obtained from convalescent DENV-1 or DENV-3 infected subjects. All sera tested exhibited high binding potency, while modest or none neutralization activities against ZIKV. Primary CD14+ monocytes, rather than B and T cells in peripheral blood mononuclear cells (PBMCs), were found to be the mediators of the enhancement of ZIKV infectivity by DENV immune sera. Monocyte-derived immature dendritic cells (DCs), but not mature DCs were highly permissive to ZIKV infection, whereas neither immature nor mature DCs could mediate enhanced ZIKV infection in the presence of DENV immune sera. In addition, antibody blocking of either FcγRI (CD64), or FcγRII (CD32), or FcγRIII (CD16) resulted in diminished ADE of ZIKV infection. Our findings provide an improved understanding of the pathogenesis of ZIKV infection, and inform rational vaccine design.

Delayed and highly specific antibody response to nonstructural protein 1 (NS1) revealed during natural human ZIKV infection by NS1-based capture ELISA.

BACKGROUND: Zika virus (ZIKV) had spread rapidly in the past few years in southern hemisphere where dengue virus (DENV) had caused epidemic problems for over half a century. The high degree of cross-reactivity of Envelope (E) protein specific antibody responses between ZIKV and DENV made it challenging to perform differential diagnosis between the two infections using standard ELISA method for E protein. METHODS: Using an IgG capture ELISA, we investigated the kinetics of nonstructural protein 1 (NS1) antibody response during natural ZIKV infection and the cross-reactivity to NS1 proteins using convalescent sera obtained from patients infected by either DENV or ZIKV. RESULTS: The analyses of the sequential serum samples from ZIKV infected individuals showed NS1 specific Abs appeared 2 weeks later than E specific Abs. Notably, human sera from ZIKV infected individuals did not contain cross-reactivity to NS1 proteins of any of the four DENV serotypes. Furthermore, four out of five NS1-specific monoclonal antibodies (mAbs) isolated from ZIKV infected individuals did not bind to DENV NS1 proteins. Only limited amount of cross-reactivity to ZIKV NS1 was displayed in 108 DENV1 immune sera at 1:100 dilution. CONCLUSIONS: The high degree of NS1-specific Abs in both ZIKV and DENV infection revealed here suggest that NS1-based diagnostics would significantly improve the differential diagnosis between DENV and ZIKV infections.

Delineating antibody recognition against Zika virus during natural infection.

Zika virus (ZIKV) is an emerging mosquito-transmitted flavivirus that shares a considerable degree of homology with dengue virus (DENV). Here, we examined longitudinal antibody response against ZIKV during natural infection in 2 convalescent individuals. By decomposing the antibody recognition into DI/DII and DIII of the E glycoprotein, we showed their development in humans followed a spatiotemporal hierarchy. Plasma binding to DI/DII appeared to peak and wane during early infection with extensive cross-reactivity with DI/DII of DENV. Binding to DIII, however, peaked early but persisted months into the infection without detectable cross-reactivity with DIII of DENV. A clear trend of increase in DIII-specific neutralizing activity was observed over the course of infection. mAbs isolated during early infection are largely DI/DII specific, weakly neutralizing, and highly cross-reactive with DENV, while those from later infection are more diverse in recognition, potently neutralizing, and ZIKV specific. The most potent neutralizing mAb targeting the DIII provided 100% protection in mice from lethal ZIKV infection and could therefore serve as a promising candidate for antibody-based therapy and prevention. The dynamic features unveiled here will assist us to better understand the pathogenesis of ZIKV infection and inform rational design of vaccines.

Characterization of the Myocarditis during the worst outbreak of dengue infection in China.

Myocarditis is a common complication of severe dengue infection. However, data about prevalence and characterization of myocarditis in dengue are still lacking. In 2014, the worst outbreak of dengue in the last two decades in China occurred. In this study, we described the clinical and laboratory diagnostic features of dengue with myocarditis. Totally, 1782 diagnosed dengue patients were admitted from August to October, 2014, all of whom were subjected to electrocardiogram, ultrasound cardiogram, and cardiac enzyme test. About 201 cases of dengue patients were diagnosed with myocarditis and the prevalence of myocarditis in hospitalized dengue was 11.28%. The prevalence of myocarditis in nonsevere dengue with warning signs and severe dengue [NSD(WS+)/SD] and nonsevere dengue without warning signs [NSD(WS-)] was 46.66% and 9.72%, respectively. The NSD(WS+)/SD patients with myocarditis presented with higher incidence of cardiac symptoms, supraventricular tachycardia (14.29% vs. 0%, P < 0.001), atrial fibrillation (25.71% vs. 10.24%, P = 0.019) and heart failure compared with NSD (WS-) patients with myocarditis. About 150 cases of dengue patients without myocarditis in the same period of time in department of Cardiology were recruited as control group. The proportion of NSD(WS+)/SD in dengue patients with and without myocarditis was 17.41% and 2.53%, respectively. Dengue patients with myocarditis experienced longer hospital stay than those without myocarditis (7.17 ±â€Š4.64 vs. 5.98 ±â€Š2.69, P = 0.008). There was no difference between patients with and without myocarditis in the proportion of symptoms, auxiliary methods abnormality, arrhythmia, and heart failure on the discharge day. Our study demonstrates the prevalence of myocarditis in worst outbreak of dengue in China was 11.28% and the incidence of myocarditis increased with the severity of dengue. The NSD(WS+)/SD patients with myocarditis presented with higher incidence of cardiac complication compared with NSD (WS-) patients with myocarditis. The prognosis of dengue patients with and without myocarditis had no significant difference even if myocarditis patients experienced longer hospital stay.

Dengue Specific Immunoglobulin A Antibody is Present in Urine and Associated with Disease Severity.

The kinetics of dengue virus (DENV)-specific IgA antibody in urine and the potential correlation with disease severity remain elusive. In this study, 262 serial urine samples from 78 laboratory-confirmed patients were assayed by a commercial immunoglobulin A (IgA) kit against DENV. All cases were classified into dengue fever (DF) and severe dengue (SD) according to the 2009 WHO/TDR guideline. The total positive rate of IgA in urine was 59%. DENV-specific IgA was detected in urine from day 2 to day 13 after the onset of illness in DF patients; While for SD patients, anti-DENV IgA could be detected till day 14. The positive rate of IgA in patients with secondary infection was higher than that in patients with primary infection. Importantly, during 4-7 days after the onset of illness, the IgA positive rate of SD patients was significantly higher than that of DF patients. Especially, the intensity of IgA signal in SD patients was obviously stronger than that in DF patient at the recovery stage. Overall, our results suggested that the existence of DENV-specific IgA antibodies in urine might be a warning sign for the severity of disease and its measurement might provide valuable guidance for proper patient management.

Epidemiological and Virological Characterizations of the 2014 Dengue Outbreak in Guangzhou, China.

Dengue used to be recognized as an imported and sporadic disease in China. Since June 2014, an unexpected large dengue outbreak has attacked Guangzhou, China, resulting in more than 40,000 cases. Among the 1,942 laboratory-confirmed hospitalized dengue cases, 121 were diagnosed as severe dengue according to the 2009 WHO guideline, and 2 patients finally died. Laboratory diagnosis and virus isolation demonstrated that the majority (96%) cases were caused by dengue virus serotype 1 (DENV-1), and the others by serotype 2 (DENV-2). 14 DENV strains were isolated from the sera of acute-phase dengue patients during this outbreak, and the complete envelope (E) gene of 12 DENV-1 strains and two DENV-2 strains were determined using RT-PCR assay. Phylogenetic analysis based on the E gene revealed the DENV-1 strains isolated during the outbreak belonged to genotype I and V, respectively. These isolates formed three clades. DENV-2 isolates were assigned to the same clade belonging to genotype cosmopolitan. These strains isolated in 2014 were closely related to the isolates obtained from the same province, Guangdong, in 2013. No amino acid mutations known to increase virulence were identified throughout the E protein of isolates in 2014. These results indicate that dengue is turning into endemic in Guangdong, China, and extensive seroepidemiological investigation and mosquito control measures are critically needed in the future.

Slow resolution of inflammation in severe adult dengue patients.

BACKGROUND: The pathogenesis of severe dengue has not been fully elucidated. The inflammatory response plays a critical role in the outcome of dengue disease. METHODS: In this study, we investigated the levels of 17 important inflammation mediators in plasma collected from mild or severe adult dengue patients at different time points to understand the contribution of inflammation to disease severity and to seek experimental evidence to optimize the existing clinical treatment strategies. Patients were simply classified as mild and severe dengue according to the 2009 WHO classification. Plasma was collected on day 3-5, 6-7, 8-10 and 14-17 of illness. Levels of 17 inflammation mediators including TNF-α, IL-1α, IFN-γ, IL-6, IFN-α, MIF, IL-10, IL-1RA, IL-8, IP-10, MCP-1, RANTES, GRO, eotaxin-1, sICAM-1 and sVCAM-1 were determined by a multiplex Luminex® system. Different trends of inflammation mediators throughout the disease were compared between mild and severe patients. RESULTS: Inflammation mediators including IL-1α, IFN-γ, IL-10, IL-8, IP-10, MCP-1 and sVCAM-1 displayed significant differences on day 8-10 of illness between mild and severe dengue patients. Their concentrations were higher in severe patients than mild ones at the same time points. Moreover, those cytokines decreased gradually in mild patients but not in severe patients. CONCLUSION: Our results revealed the coexistence of excessive inflammatory response and slow resolution of inflammation in severe adult dengue patients. Hence suppression and/or pro-resolution of inflammation could be a potential therapeutic approach for treatment of severe dengue.

Serum levels of soluble vascular cell adhesion molecules may correlate with the severity of dengue virus-1 infection in adults.

The damage of vascular endothelial cells has been speculated to be involved in the pathogenesis of dengue virus (DENV) infection. However, little is known about the role of soluble vascular cell adhesion molecule-1 (sVCAM-1) in predicting the severity of dengue infection in adults. In this study, 51 adults with DENV-1 infection (21 with severe dengue and 30 with dengue fever (DF) were included, and their serum levels of sVCAM-1 and other parameters were determined. The results indicated that the levels of sVCAM-1 were elevated on days 1-3 to 16.75 (11.55-34.74) ng/mL in the severe dengue patients. These levels increased rapidly to peak values of 43.53 (37.15-47.02) ng/mL on days 10-12 and then declined; however, the values were maintained at a high level (38.07 (26.06-39.63) ng/mL). Other parameters, including reduced platelet (PLT) counts, neutrophil (NEU) counts and increased levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and creatine kinase (CK), were also observed in the severe dengue group but not in the DF group. The levels of cytokines, such as interleukin (IL)-6, IL-10, interferon γ (IFNγ), and tumor necrosis factor α (TNF-α), were transiently increased in the severe dengue patients. Among the aforementioned parameters, only sVCAM-1 levels were significantly elevated earlier and more persistently in the severe dengue patients than in the DF patients. sVCAM-1 positively correlated with the levels of ALT, AST, LDH, TNF-α, and IL-6 and negatively correlated with the levels of PLT, NEU, and viremia. Notably, the high levels of sVCAM-1 were closely associated with the severe dengue patients. In conclusion, sVCAM-1 may be a superior indicator for monitoring the severity of dengue.