IL-17 as a putative hallmark of intense arthralgia and age-related serum immune mediator networks during acute chikungunya fever.

Introduction: The present study aimed at evaluating the systemic profile and network connectivity of immune mediators during acute chikungunya fever (CHIKF) according to days of symptoms onset and ageing.

Methods: A total of 161 volunteers (76 CHIKF patients and 85 non-infected healthy controls) were enrolled.

Results And Discussion: Data demonstrated that a massive and polyfunctional storm of serum immune mediators was observed in CHIKF.

Impact of HIV-Related Immune Impairment of Yellow Fever Vaccine Immunogenicity in People Living with HIV-ANRS 12403.

The yellow fever (YF) vaccine is one of the safest and most effective vaccines currently available. Still, its administration in people living with HIV (PLWH) is limited due to safety concerns and a lack of consensus regarding decreased immunogenicity and long-lasting protection for this population. The mechanisms associated with impaired YF vaccine immunogenicity in PLWH are not fully understood, but the general immune deregulation during HIV infection may play an important role.

Comprehensive landscape of neutralizing antibody and cell-mediated response elicited by the 1/5 fractional dose of 17DD-YF primary vaccination in adults.

The present study aimed at evaluating the YF-specific neutralizing antibody profile besides a multiparametric analysis of phenotypic/functional features of cell-mediated response elicited by the 1/5 fractional dose of 17DD-YF vaccine, administered as a single subcutaneous injection. The immunological parameters of each volunteer was monitored at two time points, referred as: before (Day 0) [Non-Vaccinated, NV] and after vaccination (Day 30-45) [Primary Vaccinees, PV]. Data demonstrated high levels of neutralizing antibodies for PV leading to a seropositivity rate of 93%.

Immune response induced by standard and fractional doses of 17DD yellow fever vaccine.

The re-emergence of yellow fever (YF) urged new mass vaccination campaigns and, in 2017, the World Health Organization approved the use of the fractional dose (FD) of the YF vaccine due to stock shortage. In an observational cross-sectional investigation, we have assessed viremia, antibodies, soluble mediators and effector and memory T and B-cells induced by primary vaccination of volunteers with FD and standard dose (SD). Similar viremia and levels of antibodies and soluble markers were induced early after immunization.

Plaque Reduction Neutralization Test (PRNT) Accuracy in Evaluating Humoral Immune Response to SARS-CoV-2.

Massive vaccination positively impacted the SARS-CoV-2 pandemic, being a strategy to increase the titers of neutralizing antibodies (NAbs) in the population. Assessing NAb levels and understanding the kinetics of NAb responses is critical for evaluating immune protection. In this study, we optimized and validated a PRNT assay to assess 50% virus neutralization and evaluated its accuracy to measure NAbs to the original strain or variant of SARS-CoV-2.

Differential gene expression of cytokines, receptors, and miRNAs in individuals living with HIV-1 and vaccinated against yellow fever.

Between 2016 and 2018, Brazil faced a yellow fever (YF) outbreak, which led to an expansion of vaccination coverage. The coexistence of the YF outbreak and the HIV-1 epidemic in Brazil raised concerns regarding the immune response and vaccine effectiveness in individuals living with HIV (PLWH). The aim of this study was to investigate the immune response to YF vaccination in PLWH and HIV-uninfected individuals as controls.

Standardization, validation, and comparative evaluation of a faster and high-performance test for quantification of yellow fever neutralizing antibodies.

Although it is considered the reference for quantification of neutralizing antibodies, classical method of the plaque reduction neutralization test (PRNT) is labor intensive, requires specific equipment and inputs, besides a long time for its finalization, even in the micro-PRNT version (in 96-well plates). It has a higher sample throughput, however the smaller wells make the reading of plaques more difficult. With an immunoenzymatic revelation step and a semi-automated reading, the μFRN-HRP (micro Focus Reduction Neutralization - Horseradish Peroxidase) is a faster and more efficient test for the quantification of YF neutralizing antibodies.

Timeline kinetics of protective immunity to SARS-CoV-2 upon primary vaccination and humoral response to variants after booster dose.

New variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have emerged, imposing the need for periodic booster doses. However, whether booster doses should be applied to the entire population or groups, and the booster doses interval, remains unclear. In this study, we evaluated humoral reactivity kinetics from before the first dose to 180 days after the third booster dose in different schedules in a well-controlled health worker cohort.

Inactivated and Immunogenic SARS-CoV-2 for Safe Use in Immunoassays and as an Immunization Control for Non-Clinical Trials.

Successful SARS-CoV-2 inactivation allows its safe use in Biosafety Level 2 facilities, and the use of the whole viral particle helps in the development of analytical methods and a more reliable immune response, contributing to the development and improvement of in vitro and in vivo assays. In order to obtain a functional product, we evaluated several inactivation protocols and observed that 0.03% beta-propiolactone for 24 h was the best condition tested, as it promoted SARS-CoV-2 inactivation above 99.

Case report: Regression of Glioblastoma after flavivirus infection.

Glioblastoma is the most frequent and aggressive primary brain cancer. In preclinical studies, Zika virus, a flavivirus that triggers the death of glioblastoma stem-like cells. However, the flavivirus oncolytic activity has not been demonstrated in human patients.

Serum soluble mediators as prognostic biomarkers for morbidity, disease outcome, and late-relapsing hepatitis in yellow fever patients.

This study described a soluble mediator storm in acute Yellow Fever/YF infection along the kinetics timeline towards convalescent disease. The analyses of the YF Viral RNAnemia, chemokines, cytokines, and growth factors were performed in YF patients at acute/(D1-15) and convalescent/(D16-315) phases. Patients with acute YF infection displayed a trimodal viremia profile spreading along D3, D6, and D8-14.

Neotropical Sylvatic Mosquitoes and Are Not Competent to Transmit 17DD Attenuated Yellow Fever Virus from Vaccinated Viremic New World Non-Human Primates.

Beside humans, thousands of non-human primates (NHPs) died during the recent outbreak caused by the yellow fever virus (YFV) in Brazil. Vaccination of NHPs against YFV with the YF 17DD attenuated virus has emerged as a public health strategy, as it would reduce sylvatic transmission while also preserving endangered susceptible species. The hypothesis of establishing an uncontrolled transmission of this attenuated virus in nature was raised.

Effectiveness, safety, and immunogenicity of half dose ChAdOx1 nCoV-19 COVID-19 Vaccine: Viana project.

Fractional dose is an important strategy to increase access to vaccines. This study evaluated the effectiveness, safety, and immunogenicity of half dose of ChAdOx1 nCoV-19 vaccine. A non-inferiority non-randomized controlled trial compared a half dose of ChAdOx1 nCoV-19 with the full dose, with an interval of 8 to 10 weeks, in individuals aged 18-49 years.

Serum biomarker profile orchestrating the seroconversion status of patients with autoimmune diseases upon planned primary 17DD Yellow fever vaccination.

The present study aimed to investigate whether the serum biomarkers of immune response orchestrate the seroconversion status in patients with autoimmune diseases (AID) upon planned primary 17DD-YF vaccination. For this purpose a total of 161 individuals were enrolled in a prospective study, including patients with Rheumatoid Arthritis (RA = 38), Spondyloarthritis (SpA = 51), Systemic Lupus Erythematosus (SLE = 21) and Sjögren's Syndrome (SS = 30) along with a group of healthy controls (HC = 21). Analysis of plaque reduction neutralization test (PRNT) titers and seropositivity rates along with the 17DD-YF viremia and serum biomarkers were carried out at distinct time points (D0/D3-4/D5-6/D7/D14-28).

Molecular and Cellular Biomarkers of COVID-19 Prognosis: Protocol for the Prospective Cohort TARGET Study.

Background: Since the beginning of the COVID-19 pandemic, the world's attention has been focused on better understanding the relation between the human host and the SARS-CoV-2 virus, as its action has led to hundreds of thousands of deaths.

Objective: In this context, we decided to study certain consequences of the abundant cytokine release over the innate and adaptive immune systems, inflammation, and hemostasis, comparing mild and severe forms of COVID-19.

Methods: To accomplish these aims, we will analyze demographic characteristics, biochemical tests, immune biomarkers, leukocyte phenotyping, immunoglobulin profile, hormonal release (cortisol and prolactin), gene expression, thromboelastometry, neutralizing antibodies, metabolic profile, and neutrophil function (reactive oxygen species production, neutrophil extracellular trap production, phagocytosis, migration, gene expression, and proteomics).

Validation of a yellow fever vaccine model using data from primary vaccination in children and adults, re-vaccination and dose-response in adults and studies with immunocompromised individuals.

Background: An effective yellow fever (YF) vaccine has been available since 1937. Nevertheless, questions regarding its use remain poorly understood, such as the ideal dose to confer immunity against the disease, the need for a booster dose, the optimal immunisation schedule for immunocompetent, immunosuppressed, and pediatric populations, among other issues. This work aims to demonstrate that computational tools can be used to simulate different scenarios regarding YF vaccination and the immune response of individuals to this vaccine, thus assisting the response of some of these open questions.

Low Vector Competence for Zika Virus from Viremic Rhesus Macaques.

Despite worldwide efforts to understand the transmission dynamics of Zika virus (ZIKV), scanty evaluation has been made on the vector competence of fed directly on viremic human and non-human primates (NHPs). We blood-fed from two districts in Rio de Janeiro on six ZIKV infected pregnant rhesus macaques at several time points, half of which were treated with Sofosbuvir (SOF). Mosquitoes were analyzed for vector competence after 3, 7 and 14 days of incubation.

Safety and immunogenicity of 17DD attenuated yellow fever vaccine in howler monkeys (Alouatta spp.).

Background: Alouatta spp. are highly susceptible to yellow fever (YF) infection and develop an often fatal disease. The threat posed by an outbreak started in 2016 leads us to investigate vaccination as a potential tool in preventing YF in non-human primates (NHP).

Planned Yellow Fever Primary Vaccination Is Safe and Immunogenic in Patients With Autoimmune Diseases: A Prospective Non-interventional Study.

Yellow Fever (YF) vaccination is suggested to induce a large number of adverse events (AE) and suboptimal responses in patients with autoimmune diseases (AID); however, there have been no studies on 17DD-YF primary vaccination performance in patients with AID. This prospective non-interventional study conducted between March and July, 2017 assessed the safety and immunogenicity of planned 17DD-YF primary vaccination in patients with AID. Adult patients with AID (both sexes) were enrolled, along with healthy controls, at a single hospital (Vitória, Brazil).

Short-Lived Immunity After 17DD Yellow Fever Single Dose Indicates That Booster Vaccination May Be Required to Guarantee Protective Immunity in Children.

The Yellow Fever (YF) vaccination is recommended for people living in endemic areas and represents the most effective strategy to reduce the risk of infection. Previous studies have warned that booster regimens should be considered to guarantee the long-term persistence of 17DD-YF-specific memory components in adults living in areas with YF-virus circulation. Considering the lower seroconversion rates observed in children (9-12 months of age) as compared to adults, this study was designed in order to access the duration of immunity in single-dose vaccinated children in a 10-years cross-sectional time-span.

Detection of Yellow Fever Virus by Quantitative Real-Time PCR (qPCR).

The recent resurgence of yellow fever virus (YFV) activity in the tropical regions of Africa and South America has sparked renewed interest in this infamous arboviral disease. Also, the development and production of viral vaccines involve several steps that need the monitoring of viral load throughout the process (antigen production, purification, and inactivation). Currently, these steps are followed by plaque lysis titration assay, whose results take about 7-10 days to come out and thus resulting in a laborious and time-consuming approach.

Impact of synthetic and biological immunomodulatory therapy on the duration of 17DD yellow fever vaccine-induced immunity in rheumatoid arthritis.

Background: The 17DD-yellow fever (YF) vaccine induces a long-lasting protective immunity, resulting from humoral and cellular immunological memory. The treatment of rheumatoid arthritis (RA) patients with disease-modifying anti-rheumatic drugs (DMARD) may affect pre-existing 17DD-vaccine protective immunity and increase the risk of acquiring YF infection. Our goal was to determine whether DMARD would affect the duration of YF-specific protective immunity in RA patients.