A5051752076- SARS-CoV-2 and COVID-19 Research
- COVID-19 Clinical Research Studies
- Long-Term Effects of COVID-19
- SARS-CoV-2 detection and testing
- Animal Virus Infections Studies
- Mosquito-borne diseases and control
- Viral gastroenteritis research and epidemiology
- Viral Infections and Vectors
- vaccines and immunoinformatics approaches
- Immunotherapy and Immune Responses
- Sepsis Diagnosis and Treatment
- Diabetes and associated disorders
- Immune cells in cancer
- COVID-19 epidemiological studies
- Vaccine Coverage and Hesitancy
- HIV Research and Treatment
- Adipokines, Inflammation, and Metabolic Diseases
- Monoclonal and Polyclonal Antibodies Research
- Neutrophil, Myeloperoxidase and Oxidative Mechanisms
- Virology and Viral Diseases
- Immune Cell Function and Interaction
- CAR-T cell therapy research
- Atherosclerosis and Cardiovascular Diseases
- Icing and De-icing Technologies
- RNA Research and Splicing
Agency for Science, Technology and Research
2017-2025
National Centre for Infectious Diseases
2021-2022
Singapore Immunology Network
2017-2022
Nanyang Technological University
2022
A*STAR Graduate Academy
2022
Duke-NUS Medical School
2021
National University of Singapore
2018-2021
Star Technology and Research (United States)
2021
University Health System
2021
National University Health System
2021
Abstract Given the ongoing SARS-CoV-2 pandemic, identification of immunogenic targets against coronavirus spike glycoprotein will provide crucial advances towards development sensitive diagnostic tools and potential vaccine candidate targets. In this study, using pools overlapping linear B-cell peptides, we report two IgG immunodominant regions on that are recognised by sera from COVID-19 convalescent patients. Notably, one is specific to SARS-CoV-2, which located in close proximity receptor...
Studies have found different waning rates of neutralising antibodies compared with binding against SARS-CoV-2. The impact antibody rate at the individual patient level on longevity immunity remains unknown. We aimed to investigate peak levels and dynamics IgG avidity maturation over time, correlate this clinical parameters, cytokines, T-cell responses.We did a longitudinal study patients who had recovered from COVID-19 up day 180 post-symptom onset by monitoring changes in using previously...
Key knowledge gaps remain in the understanding of viral dynamics and immune response Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection.We evaluated these characteristics established their association with clinical severity a prospective observational cohort study 100 patients PCR-confirmed SARS-CoV-2 infection (mean age, 46 years; 56% male; 38% comorbidities). samples (n = 74) were collected for culture, serum measurement IgM/IgG levels 30), plasma inflammatory cytokines...
SARS-CoV-2 is the novel coronavirus responsible for current COVID-19 pandemic. Severe complications are observed only in a small proportion of infected patients but cellular mechanisms underlying this progression still unknown. Comprehensive flow cytometry whole blood samples from 54 reveals dramatic increase number immature neutrophils. This strongly correlates with disease severity and associated elevated IL-6 IP-10 levels, two key players cytokine storm. The most pronounced decrease cell...
Numerous reports of vascular events after an initial recovery from COVID-19 form our impetus to investigate the impact on health recovered patients. We found elevated levels circulating endothelial cells (CECs), a biomarker injury, in convalescents compared healthy controls. In particular, those with pre-existing conditions (e.g., hypertension, diabetes) had more pronounced activation hallmarks than non-COVID-19 patients matched cardiovascular risk. Several proinflammatory and activated T...
The complications and sequelae of coronavirus disease 2019 (COVID-19) their effect on long-term health are unclear, the trajectory associated immune dysregulation is poorly understood.We conducted a prospective longitudinal multicenter cohort study at 4 public hospitals in Singapore. Patients with COVID-19 were monitored for median 6 months after recovery from acute infection. Clinical symptoms radiologic data collected, along plasma samples quantification mediators. relationship between...
Abstract Understanding the impact of age on vaccinations is essential for design and delivery vaccines against SARS-CoV-2. Here, we present findings from a comprehensive analysis multiple compartments memory immune response in 312 individuals vaccinated with BNT162b2 SARS-CoV-2 mRNA vaccine. Two vaccine doses induce high antibody T cell responses most individuals. However, recognition Spike protein Delta Omicron variants less efficient than that ancestral Wuhan strain. Age-stratified...
The immune responses and mechanisms limiting symptom progression in asymptomatic cases of SARS-CoV-2 infection remain unclear. We comprehensively characterized transcriptomic profiles, cytokine responses, neutralization capacity antibodies, cellular phenotypes patients with acute to identify potential protective mechanisms. Compared symptomatic patients, had higher counts mature neutrophils lower proportion CD169+ expressing monocytes the peripheral blood. Systemic levels pro-inflammatory...
Waning antibody levels post-vaccination and the emergence of variants concern (VOCs) capable evading protective immunity have raised need for booster vaccinations. However, which combination coronavirus disease 2019 (COVID-19) vaccines offers strongest immune response against Omicron variant is unknown.
Abstract Background Prolonged fever is associated with adverse outcomes in dengue viral infection. Similar patterns are observed COVID-19 unclear significance. Methods We conducted a hospital-based case–control study of patients admitted for prolonged (fever >7 days) and saddleback (recurrence fever, lasting <24 hours, after defervescence beyond day 7 illness). Fever was defined as temperature ≥38.0°C. Cytokines were determined multiplex microbead-based immunoassay subgroup...
A wide range of duration viral RNA shedding in patients infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has been observed. We aimed to investigate factors associated prolonged and intermittent a retrospective cohort symptomatic COVID-19 patients.Demographic, clinical laboratory data from hospitalised single centre two consecutive negative respiratory reverse transcription-polymerase chain reaction (RT-PCR) results were extracted electronic medical records....
The emergence of new SARS-CoV-2 variants, such as the more transmissible Delta and Omicron has raised concerns on efficacy COVID-19 vaccines. Here, we examined waning antibody responses against different variants following primary booster vaccination. We found that were low response was almost non-existent. Efficient boosting all including Omicron, observed a third dose. tested significantly higher at one month vaccination, compared with two months for individuals, responders identified...
Abstract Communications between immune cells are essential to ensure appropriate coordination of their activities. Here, we observed the infiltration activated macrophages into joint-footpads chikungunya virus (CHIKV)-infected animals. Large numbers CD64 + MHCII and - were present in joint-footpad, preceded by recruitment CD11b Ly6C inflammatory monocyte precursors. Recruitment differentiation these myeloid subsets dependent on CD4 T GM-CSF. Transcriptomic gene ontology analyses revealed 89...
In the early COVID-19 pandemic, strain on healthcare facilities highlighted need for reliable biomarkers to predict progression severe COVID-19. Neutrophils, most abundant leukocytes in circulation, are defenders against pathogens. a Singaporean adult cohort, neutrophil mediators were assessed their suitability as prognostic of complications. Plasma levels myeloperoxidase, elastase, soluble urokinase plasminogen activator receptor (suPAR) and suppressor tumorigenicity 2 (sST2) 35 non-severe...
Chikungunya virus (CHIKV) has been a worldwide threat since its reemergence in La Reunion Island 2004. Expression of the interferon-stimulated protein Viperin correlates with viral load burden patients, and studies mice have demonstrated role to limit disease severity against CHIKV infection. Using Viperin-/- mice, we aimed understand contribution T-cell immune response CHIKV. CD4 depletion showed that increased late acute joint inflammation (5-8 d postinfection) was exclusively mediated by...
SARS-CoV-2 was first detected in late December 2019, however, the few months that followed, resultant COVID-19 disease has developed into a devastating pandemic around world [[1]https://covid19.who.int/.Google Scholar]. This led to race produce safe and efficacious vaccine record time. In less than year, BNT162b2, an mRNA-based by BioNTech-Pfizer [[2]Polack FP Thomas SJ Kitchin N et al.Safety efficacy of BNT162b2 mRNA Covid-19 vaccine.N Engl J Med. 2020; 383: 2603-2615Crossref PubMed Scopus...
SARS-CoV-2, the causative agent of COVID-19, is a threat to public health. Evidence suggests increased neutrophil activation and endothelial glycocalyx (EG) damage are independently associated with severe COVID-19. Here, we hypothesised that an level blood myeloperoxidase (MPO) soluble EG breakdown, inhibiting MPO activity may reduce damage.Analysing subset acute convalescent COVID-19 plasma, 10 from 15 non-severe cases, 9 pre-COVID-19 controls, determined levels, proteins (syndecan-1...
Due to the paucity of longitudinal molecular studies COVID-19, particularly those covering early stages infection (Days 1-8 symptom onset), our understanding host response over disease course is limited. We perform single cell RNA-seq on 286 blood samples from 108 age- and sex-matched COVID-19 patients, including 73 with samples. examine discrete subtypes continuous states longitudinally, we identify upregulation type I IFN-stimulated genes (ISGs) as predominant signature subsequent...
Biomarkers play a pivotal role in the diagnosis and management of patients with acute coronary syndrome. This study aimed to investigate differences level several biomarkers, i.e. C-reactive protein, myeloperoxidase, soluble CD40 ligand placental growth factor, between syndrome chronic stable angina patients. The relationship these biomarkers circulation systemic was also investigated. A total 79 were recruited this study. blood sampled from occluded artery, while peripheral venous withdrawn...
Abstract Objectives While the safety of non‐steroidal anti‐inflammatory drugs in COVID‐19 has been questioned, they may be beneficial given hyper‐inflammatory immune response associated with severe disease. We aimed to assess and potential efficacy cyclooxygenase‐2 (COX‐2) selective inhibitors high‐risk patients. Methods Retrospective study patients pneumonia aged ≥ 50 years who were admitted hospital. Adverse outcomes analysed included supplemental oxygen use, intensive care unit admission,...