Concluding Remarks for the Special Issue on RNA Viruses and Antibody Response, Second Edition.

The emergence and re-emergence of RNA viruses pose a constant, significant global health problem [...

Insights from Avian Influenza: A Review of Its Multifaceted Nature and Future Pandemic Preparedness.

Avian influenza viruses (AIVs) have posed a significant pandemic threat since their discovery. This review mainly focuses on the epidemiology, virology, pathogenesis, and treatments of avian influenza viruses. We delve into the global spread, past pandemics, clinical symptoms, severity, and immune response related to AIVs.

Concluding Remarks for the Special Issue on RNA Viruses and Antibody Response.

Infectious diseases represent one of the major public health concerns on the global level [...

Systematic analysis of disease-specific immunological signatures in patients with febrile illness from Saudi Arabia.

Objectives: Little is known about the prevalence of febrile illness in the Arabian region as clinical, laboratory and immunological profiling remains largely uncharacterised.

Methods: A total of 2018 febrile patients from Jazan, Saudi Arabia, were recruited between 2014 and 2017. Patients were screened for dengue and chikungunya virus, , , , group A streptococcus and .

Erratum: Novel differential linear B-cell epitopes to identify Zika and dengue virus infections in patients.

[This corrects the article DOI: 10.1002/cti2.1066.

Novel differential linear B-cell epitopes to identify Zika and dengue virus infections in patients.

Objectives: Recent Zika virus (ZIKV) outbreaks challenged existing laboratory diagnostic standards, especially for serology-based methods. Because of the genetic and structural similarity of ZIKV with other flaviviruses, this results in cross-reactive antibodies, which confounds serological interpretations.

Methods: Plasma from Singapore ZIKV patients was screened longitudinally for antibody responses and neutralising capacities against ZIKV.

ZIKV-Specific NS1 Epitopes as Serological Markers of Acute Zika Virus Infection.

Background: Zika virus (ZIKV) infections have reemerged as a global health issue due to serious clinical complications. Development of specific serological assays to detect and differentiate ZIKV from other cocirculating flaviviruses for accurate diagnosis remains a challenge.

Methods: We investigated antibody responses in 51 acute ZIKV-infected adult patients from Campinas, Brazil, including 7 pregnant women who later delivered during the study.

Multimodal assessments of Zika virus immune pathophysiological responses in marmosets.

Animal models that recapitulate the human pathophysiology have been developed as useful research tools. Although laboratory mice are widely used, they are phylogenetically "distant" to humans. New world monkeys, such as the common marmoset (Callithrix jacchus) have steadily gained prominence.

The 2016 Singapore Zika virus outbreak did not cause a surge in Guillain-Barré syndrome.

Although individuals with Zika virus (ZIKV) antibodies were reported in Malaya in mid-1950s, entomological and human surveillance in Singapore did not identify autochthonous transmission until the outbreak of August-November, 2016. A total of 455 cases from 15 separate clusters were identified. We asked if this ZIKV outbreak increased the incidence of Guillain-Barré syndrome (GBS) and aimed to characterize these cases.

Longitudinal Study of Cellular and Systemic Cytokine Signatures to Define the Dynamics of a Balanced Immune Environment During Disease Manifestation in Zika Virus-Infected Patients.

Background: Since its unexpected reemergence, Zika virus (ZIKV) has caused numerous outbreaks globally. This study characterized the host immune responses during ZIKV infection.

Methods: Patient samples were collected longitudinally during the acute, convalescence and recovery phases of ZIKV infection over 6 months during the Singapore outbreak in late 2016.

Antibody-mediated enhancement aggravates chikungunya virus infection and disease severity.

The arthropod-transmitted chikungunya virus (CHIKV) causes a flu-like disease that is characterized by incapacitating arthralgia. The re-emergence of CHIKV and the continual risk of new epidemics have reignited research in CHIKV pathogenesis. Virus-specific antibodies have been shown to control virus clearance, but antibodies present at sub-neutralizing concentrations can also augment virus infection that exacerbates disease severity.

Seroprevalence of antibodies against chikungunya virus in Singapore resident adult population.

Objectives: We determined the seroprevalence of chikungunya virus (CHIKV) infection in the adult resident population in Singapore following local outbreaks of chikungunya fever (CHIKF) in 2008-2009.

Methods: Our cross-sectional study involved residual sera from 3,293 adults aged 18-79 years who had participated in the National Health Survey in 2010. Sera were tested for IgG antibodies against CHIKV and dengue virus (DENV) and neutralizing antibodies against CHIKV.

Specific Biomarkers Associated With Neurological Complications and Congenital Central Nervous System Abnormalities From Zika Virus-Infected Patients in Brazil.

Background: Zika virus (ZIKV) infections have been linked to different levels of clinical outcomes, ranging from mild rash and fever to severe neurological complications and congenital malformations.

Methods: We investigated the clinical and immunological response, focusing on the immune mediators profile in 95 acute ZIKV-infected adult patients from Campinas, Brazil. These patients included 6 pregnant women who later delivered during the course of this study.

Cross-reactive dengue human monoclonal antibody prevents severe pathologies and death from Zika virus infections.

Zika virus (ZIKV) infections have been linked with neurological complications and congenital Zika syndrome. Given the high level of homology between ZIKV and the related flavivirus dengue virus (DENV), we investigated the level of cross-reactivity with ZIKV using a panel of DENV human mAbs. A majority of the mAbs showed binding to ZIKV virions, with several exhibiting neutralizing capacities against ZIKV in vitro.

Structural Optimizations of Thieno[3,2-b]pyrrole Derivatives for the Development of Metabolically Stable Inhibitors of Chikungunya Virus.

Chikungunya virus (CHIKV) is a re-emerging vector-borne alphavirus, and there is no approved effective antiviral treatment currently available for CHIKV. We previously reported the discovery of thieno[3,2-b]pyrrole 1b that displayed good antiviral activity against CHIKV infection in vitro. However, it has a short half-life in the presence of human liver microsomes (HLMs) (T = 2.

Severity of Plasma Leakage Is Associated With High Levels of Interferon γ-Inducible Protein 10, Hepatocyte Growth Factor, Matrix Metalloproteinase 2 (MMP-2), and MMP-9 During Dengue Virus Infection.

Background:  Dengue virus infection typically causes mild dengue fever, but, in severe cases, life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) occur. The pathophysiological hallmark of DHF and DSS is plasma leakage that leads to enhanced vascular permeability, likely due to a cytokine storm.

Methods:  Ninety patients with dengue during 2010-2012 in Singapore were prospectively recruited and stratified according to their disease phase, primary and secondary infection status, and disease severity, measured by plasma leakage.

Early clearance of Chikungunya virus in children is associated with a strong innate immune response.

Chikungunya fever (CHIKF) is a global infectious disease which can affect a wide range of age groups. The pathological and immunological response upon Chikungunya virus (CHIKV) infection have been reported over the last few years. However, the clinical profile and immune response upon CHIKV infection in children remain largely unknown.

Trisubstituted Thieno[3,2-b]pyrrole 5-Carboxamides as Potent Inhibitors of Alphaviruses.

Chikungunya virus (CHIKV) is a re-emerging vector-borne alphavirus and is transmitted to humans by Aedes mosquitoes. Despite the re-emergence of CHIKV as an epidemic threat, there is no approved effective antiviral treatment currently available for CHIKV. Herein, we report the synthesis and structure-activity relationship studies of a class of thieno[3,2-b]pyrroles and the discovery of a trisubstituted thieno[3,2-b]pyrrole 5-carboxamide 15c that exhibits potent inhibitory activity against in vitro CHIKV infection.

A sensitive epitope-blocking ELISA for the detection of Chikungunya virus-specific antibodies in patients.

Chikungunya fever (CHIKF) has re-emerged as an arboviral disease that mimics clinical symptoms of other diseases such as dengue, malaria, as well as other alphavirus-related illnesses leading to problems with definitive diagnosis of the infection. Herein we describe the development and evaluation of a sensitive epitope-blocking ELISA (EB-ELISA) capable of specifically detecting anti-chikungunya virus (CHIKV) antibodies in clinical samples. The assay uses a monoclonal antibody (mAb) that binds an epitope on the E2 protein of CHIKV and does not exhibit cross-reactivity to other related alphaviruses.

Caribbean and La Réunion Chikungunya Virus Isolates Differ in Their Capacity To Induce Proinflammatory Th1 and NK Cell Responses and Acute Joint Pathology.

Unlabelled: Chikungunya virus (CHIKV) is a mosquito-borne arthralgic alphavirus that has garnered international attention as an important emerging pathogen since 2005. More recently, it invaded the Caribbean islands and the Western Hemisphere. Intriguingly, the current CHIKV outbreak in the Caribbean is caused by the Asian CHIKV genotype, which differs from the La Réunion LR2006 OPY1 isolate belonging to the Indian Ocean lineage.

Expanding regulatory T cells alleviates chikungunya virus-induced pathology in mice.

Unlabelled: Chikungunya virus (CHIKV) infection is a re-emerging pandemic human arboviral disease. CD4 T cells were previously shown to contribute to joint inflammation in the course of CHIKV infection in mice. The JES6-1 anti-IL-2 antibody selectively expands mouse regulatory T cells (Tregs) by forming a complex with IL-2.

A Systematic Meta-analysis of Immune Signatures in Patients With Acute Chikungunya Virus Infection.

Background: Individuals infected with chikungunya virus (CHIKV) normally exhibit a variety of clinical manifestations during the acute phase of infection. However, studies in different patient cohorts have revealed that disease manifestations vary in frequency.

Methods: Disease profiles between patients with acute CHIKV-infection and febrile patients without CHIKV were compared and examined to determine whether any clinical presentations were associated with the clinical outcome of CHIKV infection.

Sero-prevalence and cross-reactivity of chikungunya virus specific anti-E2EP3 antibodies in arbovirus-infected patients.

Chikungunya virus (CHIKV) and clinically-related arboviruses cause large epidemics with serious economic and social impact. As clinical symptoms of CHIKV infections are similar to several flavivirus infections, good detection methods to identify CHIKV infection are desired for improved treatment and clinical management. The strength of anti-E2EP3 antibody responses was explored in a longitudinal study on 38 CHIKV-infected patients.