Application of One-Step Reverse Transcription Droplet Digital PCR for Dengue Virus Detection and Quantification in Clinical Specimens.

Detection and quantification of viruses in laboratory and clinical samples are standard assays in dengue virus (DENV) studies. The quantitative reverse transcription polymerase chain reaction (qRT-PCR) is considered to be the standard for DENV detection and quantification due to its high sensitivity. However, qRT-PCR offers only quantification relative to a standard curve and consists of several "in-house" components resulting in interlaboratory variations.

High performance dengue virus antigen-based serotyping-NS1-ELISA (plus): A simple alternative approach to identify dengue virus serotypes in acute dengue specimens.

Dengue hemorrhagic fever (DHF) is caused by infection with dengue virus (DENV). Four different serotypes (DENV1-4) co-circulate in dengue endemic areas. The viral RNA genome-based reverse-transcription PCR (RT-PCR) is the most widely used method to identify DENV serotypes in patient specimens.

Longitudinal Analysis of Antibody Cross-neutralization Following Zika Virus and Dengue Virus Infection in Asia and the Americas.

Background: The 4 dengue virus serotypes (DENV1-4) and Zika virus (ZIKV) are related mosquito-borne flaviviruses of major importance globally. While monoclonal antibodies and plasma from DENV-immune donors can neutralize or enhance ZIKV in vitro and in small-animal models, and vice versa, the extent, duration, and significance of cross-reactivity in humans remains unknown, particularly in flavivirus-endemic regions.

Methods: We studied neutralizing antibodies to ZIKV and DENV1-4 in longitudinal serologic specimens collected through 3 years after infection from people in Latin America and Asia with laboratory-confirmed DENV infections.

Germline bias dictates cross-serotype reactivity in a common dengue-virus-specific CD8 T cell response.

Adaptive immune responses protect against infection with dengue virus (DENV), yet cross-reactivity with distinct serotypes can precipitate life-threatening clinical disease. We found that clonotypes expressing the T cell antigen receptor (TCR) β-chain variable region 11 (TRBV11-2) were 'preferentially' activated and mobilized within immunodominant human-leukocyte-antigen-(HLA)-A*11:01-restricted CD8 T cell populations specific for variants of the nonstructural protein epitope NS3 that characterize the serotypes DENV1, DENV3 and DENV4. In contrast, the NS3-DENV2-specific repertoire was largely devoid of such TCRs.

MAIT cells are activated during human viral infections.

Mucosal-associated invariant T (MAIT) cells are abundant in humans and recognize bacterial ligands. Here, we demonstrate that MAIT cells are also activated during human viral infections in vivo. MAIT cells activation was observed during infection with dengue virus, hepatitis C virus and influenza virus.

High Anti-Dengue Virus Activity of the OAS Gene Family Is Associated With Increased Severity of Dengue.

Dengue is a mosquito-borne viral disease that afflicts millions of individuals worldwide every year. Infection by any of the 4 dengue virus (DENV) serotypes can result in a spectrum of disease severity. We investigated the impact of variants of interferon-regulated innate immunity genes with a potent antiviral effect on the outcome of DENV infection.

Microparticles provide a novel biomarker to predict severe clinical outcomes of dengue virus infection.

Unlabelled: Shedding of microparticles (MPs) is a consequence of apoptotic cell death and cellular activation. Low levels of circulating MPs in blood help maintain homeostasis, whereas increased MP generation is linked to many pathological conditions. Herein, we investigated the role of MPs in dengue virus (DENV) infection.

Invariant NKT cell response to dengue virus infection in human.

Background: Dengue viral infection is a global health threat without vaccine or specific treatment. The clinical outcome varies from asymptomatic, mild dengue fever (DF) to severe dengue hemorrhagic fever (DHF). While adaptive immune responses were found to be detrimental in the dengue pathogenesis, the roles of earlier innate events remain largely uninvestigated.

Complement alternative pathway genetic variation and Dengue infection in the Thai population.

Dengue disease is a mosquito-borne infection caused by Dengue virus. Infection may be asymptomatic or variably manifest as mild Dengue fever (DF) to the most severe form, Dengue haemorrhagic fever (DHF). Mechanisms that influence disease severity are not understood.

An in-depth analysis of original antigenic sin in dengue virus infection.

The evolution of dengue viruses has resulted in four antigenically similar yet distinct serotypes. Infection with one serotype likely elicits lifelong immunity to that serotype, but generally not against the other three. Secondary or sequential infections are common, as multiple viral serotypes frequently cocirculate.

Immunodominant T-cell responses to dengue virus NS3 are associated with DHF.

Dengue infections are increasing at an alarming rate in many tropical and subtropical countries, where epidemics can put health care systems under extreme pressure. The more severe infections lead to dengue hemorrhagic fever (DHF), which can be life threatening. A variety of viral and host factors have been associated with the severity of dengue infections.

Cross-reacting antibodies enhance dengue virus infection in humans.

Dengue virus co-circulates as four serotypes, and sequential infections with more than one serotype are common. One hypothesis for the increased severity seen in secondary infections is antibody-dependent enhancement (ADE) leading to increased replication in Fc receptor-bearing cells. In this study, we have generated a panel of human monoclonal antibodies to dengue virus.

A complex interplay among virus, dendritic cells, T cells, and cytokines in dengue virus infections.

Severe dengue virus (DV) infections can cause the life-threatening condition dengue hemorrhagic fever, which is characterized by a severe plasma leak, thrombocytopenia, hemorrhage, and, in severe cases, circulatory collapse and death. There is now much evidence that pre-existing immunity to DV can enhance disease when an individual becomes infected on a second or sequential occasion. It has been shown that in contrast to infected dendritic cells (DC), noninfected bystander DC underwent maturation in dengue infection.

Successful separation of thoracopagus conjoined twins with a single extra-hepatic biliary system.

A pair of thoracopagus conjoined twins were separated at the age of 3 months at Khon Kaen Regional Hospital, Thailand on November 19, 2004. Pre-operative investigations showed separate hearts, joined duodenum, and fusion of the livers. Separation of the extra-hepatic biliary systems was suspected.

Vascular leakage in severe dengue virus infections: a potential role for the nonstructural viral protein NS1 and complement.

Background: Vascular leakage and shock are the major causes of death in patients with dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Thirty years ago, complement activation was proposed to be a key underlying event, but the cause of complement activation has remained unknown.

Methods: The major nonstructural dengue virus (DV) protein NS1 was tested for its capacity to activate human complement in its membrane-associated and soluble forms.

T cell responses in dengue hemorrhagic fever: are cross-reactive T cells suboptimal?

Dengue virus infection poses a growing public health and economic burden in a number of tropical and subtropical countries. Dengue circulates as a number of quasispecies, which can be divided by serology into four groups or serotypes. An interesting feature of Dengue, recognized over five decades ago, is that most severe cases that show hemorrhagic fever are not suffering from a primary infection.

A variant in the CD209 promoter is associated with severity of dengue disease.

Dengue fever and dengue hemorrhagic fever are mosquito-borne viral diseases. Dendritic cell-specific ICAM-3 grabbing nonintegrin (DC-SIGN1, encoded by CD209), an attachment receptor of dengue virus, is essential for productive infection of dendritic cells. Here, we report strong association between a promoter variant of CD209, DCSIGN1-336, and risk of dengue fever compared with dengue hemorrhagic fever or population controls.

Original antigenic sin and apoptosis in the pathogenesis of dengue hemorrhagic fever.

Dengue virus presents a growing threat to public health in the developing world. Four major serotypes of dengue virus have been characterized, and epidemiological evidence shows that dengue hemorrhagic fever (DHF), the more serious manifestation of the disease, occurs more frequently upon reinfection with a second serotype. We have studied dengue virus-specific T-cell responses in Thai children.

Failure of carbazochrome sodium sulfonate (AC-17) to prevent dengue vascular permeability or shock: a randomized, controlled trial.

Objective: We studied the ability of carbazochrome sodium sulfonate (AC-17) to prevent capillary permeability in dengue hemorrhagic fever/dengue shock syndrome.

Method: A randomized, placebo-controlled trial in 95 children stratified by age and sex was conducted in two hospitals during 1992. AC-17 (n = 45 cases) or B vitamins as placebo (n = 50) were given as a bolus infusion and then as a continuous drip for 24 hours; a total of 300 mg of AC-17 was administered on the first 2 days and 150 mg on the third day.

Failure of high-dose methylprednisolone in established dengue shock syndrome: a placebo-controlled, double-blind study.

Objective: Steroids are widely used in Thailand and other dengue-endemic countries to treat severe dengue shock syndrome. This study was designed to determine whether a single high dose of methylprednisolone will reduce mortality in children with dengue shock syndrome who did not respond to simple fluid and plasma replacement therapy.

Methods: A prospective, randomized, double-blind, controlled trial was conducted in two hospitals in Khon Kaen Thailand during June to September in 1987 and 1988.