Reynaldo Dietze

Universidade Federal do Espírito Santo | UFES · Nucleo de Doenças Infecciosas - Centro de Ciencias da Saude - UFES

BACKGROUND: Isoniazid preventive therapy (IPT) is highly effective in preventing TB disease; however, its long-term benefit in household contacts (HHCs) of infectious TB cases is unclear. METHODS: We conducted a retrospective analysis of two household contact studies in Vitoria, ES, Brazil, between 2008 and 2015. Households with smear-positive, cul...

Mechanisms underlying variability in transmission of Mycobacterium tuberculosis strains remain undefined. By characterizing high and low transmission strains of M.tuberculosis in mice, we show here that high transmission M.tuberculosis strain induce rapid IL-1R-dependent alveolar macrophage migration from the alveolar space into the interstitium an...

Congenital Zika virus (ZIKV) infection results in neurodevelopmental deficits in up to 14% of infants born to ZIKV-infected mothers. Neutralizing antibodies are a critical component of protective immunity. Here, we demonstrate that plasma IgM responses contribute to ZIKV immunity in pregnancy, mediating neutralization up to three months post sympto...

Background: Takeda's live attenuated tetravalent dengue vaccine candidate (TAK-003) is under evaluation in a long-term clinical trial across eight dengue-endemic countries. Previously, we have reported its efficacy and safety in both seronegative and seropositive participants and that its performance varies by serotype, with some decline in effica...

BackgroundRegulatory T cells (Tregs) play a critical role during Mycobacterium tuberculosis (Mtb) infection, modulating host responses while neutralizing excessive inflammation. However, their impact on regulating host protective immunity is not completely understood. Here, we demonstrate that Treg cells abrogate the in vitro microbicidal activity...

Toxoplasmosis is able to cause death and/or sequelae in foetuses from pregnant women and immunocompromised individuals. The early diagnosis, able to differentiate acute from chronic phases, is essential to define the treatment against this disease and minimize the risk of complications. Here we describe a peptide derived from microneme 8 (pMIC8) pr...

Background The impact of SARS-CoV-2 in regions endemic for both Dengue and Chikungunya is still not fully understood. Considering that symptoms/clinical features displayed during Dengue, Chikungunya and SARS-CoV-2 acute infections are similar, undiagnosed cases of SARS-CoV-2 in co-endemic areas may be more prevalent than expected. This study was co...

Background Takeda’s dengue vaccine is under evaluation in an ongoing Phase 3 efficacy study; we present an update after 2 years. Methods 20,099 children (4–16 years old) were randomized to receive two doses of TAK-003 or placebo three months apart and are under long-term febrile surveillance to detect dengue by serotype-specific RT-PCR. (NCT027479...

Background: We previously described an increased immune response 28 days after a booster dose of the live, attenuated, tetravalent dengue vaccine (CYD-TDV) in healthy adolescents and adults in Latin America (CYD64, NCT02623725). This follow-up study evaluated immune response persistence and safety of a CYD-TDV booster dose up to Month (M) 24 post-...

Little is known about the physiology of latent Mycobacterium tuberculosis infection. We studied the mutational rates of 24 index tuberculosis (TB) cases and their latently infected household contacts who developed active TB up to 5.25 years later, as an indication of bacterial physiological state and possible generation times during latent TB infec...

This study aimed to evaluate the dynamics of culture filtrate dependent subpopulations of Mycobacterium tuberculosis in a prospective cohort study following 17 patients through a standard 6-month anti-tuberculosis regimen, performing monthly sputum collection. We performed the limiting dilution method with culture filtrate supplementation of liquid...

Defined as the time between symptom onset of an infector and infectee pair, serial interval (SI) is commonly used to understand infectious diseases transmission. Slow progression to active disease, as well as the small percentage of individuals who will eventually develop active disease, complicate the estimation of the serial interval for tubercul...

In this study, we report unexpected results we encountered while conducting early development work for a new ultra-sensitive molecular TB assay with established sensitivity superior to mycobacterial cultures. By interrogating for the first time ever, respiratory samples for the presence of M. tuberculosis at a level of detection below that of curre...

Background A substantial unmet need remains for safe and effective vaccines against dengue virus disease, particularly for individuals who are dengue-naive and those younger than 9 years. We aimed to assess the efficacy, safety, and immunogenicity of a live attenuated tetravalent dengue vaccine (TAK-003) in healthy children aged 4–16 years. Method...

Cytotoxic activity mediated by CD8+ T cells is the main signature of the immunopathogenesis of cutaneous leishmaniasis (CL). Here, we performed a broad evaluation of NK cells phenotypic and functional features during cutaneous leishmaniasis. We demonstrate for the first time that CL patients present the accumulation of circulating NK cells with mul...

The goal of this study was to identify individuals at risk of progression and reactivation among household contacts (HHC) of pulmonary TB cases in Vitoria, Brazil. We first evaluated the predictive performance of six published signatures on the transcriptional dataset obtained from peripheral blood mononuclear cell samples from HHC that either prog...

Background: Dengue, a mosquito-borne viral disease, was designated a World Health Organization top 10 threat to global health in 2019. Methods: We present primary efficacy data from part 1 of an ongoing phase 3 randomized trial of a tetravalent dengue vaccine candidate (TAK-003) in regions of Asia and Latin America in which the disease is endemi...

Household contact studies of tuberculosis (TB) are a common way to study disease transmission dynamics. However these studies lack a mechanism for accounting for community transmission, which is known to be significant, particularly in high burden settings. We illustrate a statistical approach for estimating both the correlates with transmission of...

Biomarkers for TB treatment response and outcome are needed. This study characterize changes in immune profiles during TB treatment, define biosignatures associated with treatment outcomes, and explore the feasibility of predictive models for relapse. Seventy-two markers were measured by multiplex cytokine array in serum samples from 78 cured, 12 r...

In India visceral leishmaniasis (VL) caused by Leishmania donovani has been successfully treated with miltefosine with a cure rate of > 90%. To assess the efficacy and safety of oral miltefosine in L. infantum-causing Brazilian VL patients, a phase II, open-label, dose-escalation study of oral miltefosine was conducted in children (ages 2-12) and a...

Background: Epidemiologic data suggests that only a minority of tuberculosis (TB) patients are infectious. Cough aerosol sampling is a novel quantitative method to measure TB infectiousness. Methods: We analyzed data from three studies conducted in Uganda and Brazil over a 13-year period. We included sputum acid fast bacilli (AFB) and culture po...

Author summary Mycobacterium tuberculosis (Mtb), the bacteria that causes tuberculosis (TB), is spread through the air from infected patients to their close contacts. In a household contact (HHC) study of patients with TB, we found that in some households a larger proportion of contacts were infected with Mtb compared to other households. We catego...

Bacterial burden in CeHeB/FeJ animals infected with Mtb-HT1 and Mtb-LT1. C3HeB/FeJ animals were infected with low dose of Mtb and lungs, mediastinal lymph nodes and spleens were plated at 12-weeks post infection. Two-way ANOVA showed significant difference between animals infected with Mtb-HT and Mtb-LT strains Each group includes 4–5 mice per time...

Higher bacterial burden and more granulomatous lesions in the lungs of Mtb-LT1 infected C57BL/6J and BALB/c mice. C57BL/6 and BALB/c mice were aerosol infected with a low dose of Mtb-HT1 and Mtb-LT1 strains. CFU/mouse was enumerated by plating lung homogenates at indicated time points following infection (A). Data are presented as mean +/- SEM; **p...

Increased inflammatory response in Mtb-LT infected mice. Lung lysates from four week-infected C3HeB/FeJ mice were obtained after homogenizing lung tissue in 1ml PBS and 2X protease inhibitor (ThermoFisher). Levels of different immune mediators were evaluated in filtered cell-free lysates using singleplex ELISA and/or multiplex MesoScale Discovery (...

TST positivity in HHC infected with Mtb-HT and Mtb-LT strains. (PDF)

Bacterial growth and effect of MPN. Frozen stocks of the indicated strains were used to inoculate 7H9 media containing 0.05% Tween 80. The samples were allowed to grow 3 days in liquid culture reaching mid-log phase. The growing culture was split 1:100 into flasks containing 7H9 + Tween or flasks containing 7H9 + Tween and 100nM MPN. The OD 600 fro...

Increased bacterial dissemination in C3HeB/FeJ mice infected with Mtb-LT strains. C3HeB/FeJ animals were infected with a low dose inoculum of Mtb-HT1, Mtb-HT2, Mtb-HT3, Mtb-LT1, Mtb-LT2, and Mtb-LT3 strains. At 4 and 12 weeks following aerosol infection, serial dilutions of spleen and liver homogenates were plated on 7H11 agar plates and the bacter...

Presence of cholesterol crystals in lung lesions of Mtb-LT infected mice. Formalin-fixed, paraffin-embedded lung tissue was obtained from mice at 12 weeks following infection with Mtb-LT1 and sections were stained using a standard H&E protocol. Arrows point to the presence of cholesterol crystals. (PDF)

Lung pathology in Mtb-HT3 and Mtb-LT3 infected mice. Multiple lung lobes from Mtb-HT3 (A) and Mtb-LT3 (B) infected C3HeB/FeJ animals were fixed, paraffin embedded and stained using H&E protocol, at week 12 post infection. Black box = presence of fibrotic lesions; *green = discrete lesion; and *yellow = diffused inflammation. (PDF)

Background: The tetravalent dengue vaccine (CYD-TDV, Dengvaxia, Sanofi Pasteur) demonstrated efficacy in 2 previous phase III trials conducted in endemic countries. Neutralizing antibodies (NAbs) elicited by 3 doses of this vaccine have been associated with efficacy. Long-term follow-up data has shown that NAb immune responses tend to wane over ti...

The use of adjuvants in vaccine formulations is a well-established practice to improve immunogenicity and protective immunity against diseases. Previously, we have demonstrated the feasibility of intranasal vaccination with the antigen of killed Leishmania amazonensis promastigotes (LaAg) against experimental leishmaniasis. In this work, we sought...

Background: Latent tuberculous infection (LTBI) can function as a 'reservoir' for Mycobacterium tuberculosis. Given that T-regulatory cell (Treg) numbers are augmented in LTBI, it is likely that Toll-like receptors (TLRs) may have a role in Treg function. Elucidation of the immune mechanisms associated with tuberculosis (TB) development may help t...

Leishmania (Viannia) braziliensis induces American tegumentary leishmaniasis that ranges in severity from the milder form, cutaneous (CL) to severe disseminated cutaneous leishmaniasis. Patients with CL develop a cell-mediated Th1 immune response accompanied by production of inflammatory cytokines, which contribute to parasite control and pathogene...

Clinical features of cutaneous leishmaniasis patients and healthy controls participating in the study. NA, Not applicable.

Correlation between cytokines levels and frequency of CD4+ EMRA subset in HC (○) or CL patients (■) were tested using Pearson's correlation test. For all tests, a p < 0.05 was considered statistically significant.

Characterization of CLA expression in T cells during cutaneous leishmaniasis. CD4+ and CD8+ T cells isolated from healthy controls (HC) (n = 12) and patients with active cutaneous leishmaniasis patients (CL) (n = 14) were stained for cutaneous leucocyte-associated antigen (CLA) and analyzed by flow cytometry. Representative cytometry plots and cumu...

Proliferative capacity evaluated by Ki67 staining of CD4+ and CD8+ subsets [Naïve; Central memory (CM) and Effector memory (EF)] from HC or CL stimulated with 0.5 μg/mL of anti-CD3 for 72 h. The graphs show the mean ± SEM. P-values were calculated using repeated measures ANOVA with the Tukey correction used for post-hoc testing. **p < 0.01, ****p <...

Inflammatory profile correlates with differentiation state. Correlation between cytokines levels and frequency of CD4 (A) and CD8 (B) subsets in HC or CL patients were tested using Pearson's 1124 correlation test. For all tests, a p < 0.05 was considered statistically significant.

Background Mycobacterium tuberculosis cultures of cough-generated aerosols from patients with pulmonary tuberculosis (TB) are a quantitative method to measure infectiousness and to predict secondary outcomes in exposed contacts. However, their reproducibility has not been established. Objective To evaluate the predictive value of colony-forming un...

Table A: Additional Characteristics of 48 Index Tuberculosis Cases and their 230 Household Contacts Figure A: Study profile. IC = Index tuberculosis (TB) cases; HHC = Household contacts; TST = Tuberculin skin test; IGRA = Interferon gamma release assay (Quantiferon Gold In-Tube). (DOCX)

Database of 48 index tuberculosis cases and their 230 household contacts. (XLSX)

Background: Miltefosine has been used successfully to treat visceral leishmaniasis (VL) in India, but it was unsuccessful for VL in a clinical trial in Brazil. Methods: To identify molecular markers that predict VL treatment failure whole genome sequencing of 26 L. infantum isolates, from cured and relapsed patients allowed a GWAS analysis of SN...

Background Approximately 5% of patients with drug-susceptible tuberculosis have a relapse after 6 months of first-line therapy, as do approximately 20% of patients after 4 months of short-course therapy. We postulated that by analyzing pretreatment isolates of Mycobacterium tuberculosis obtained from patients who subsequently had a relapse or were...

Globally, the prevalence of tuberculosis (TB) disease is higher in males. This study examined the effect of sex and age on Mycobacterium tuberculosis (Mtb) infection. Demographic and exposure data were collected on household contacts of sputum smear-positive pulmonary TB patients in Brazil. Contacts with tuberculin skin test induration ⩾10 mm at ba...

Our study was designed to test the hypothesis that an early morning sputum may be sufficient for calculation of early bactericidal activity (EBA). Patients underwent sputum collection randomly (spot, 5 h and 12 h) in consecutive days. The median CFU count in the spot samples group was 5.67 log10 CFU/mL compared to 6.17 log10 CFU/mL in 5 h and 6.23...

Tuberculosis (TB) is an infectious disease of global importance with major economic and social burden accounting for 25% of all avoidable deaths in developing countries. Extrapulmonary involvement may occur either in association with clinically apparent pulmonary tuberculosis or in isolation. This cross-sectional descriptive study aimed to evaluate...

Household contacts of pulmonary tuberculosis (TB) patients are at increased risk of TB infection and disease. However, their risk in relation to the intensity of exposure remains unknown. We studied smear-positive TB cases and their household contacts in Vitória, Brazil. We collected clinical, demographic and radiographic information from TB cases,...

Background: The Xpert MTB/RIF assay is an automated molecular test that has improved the detection of tuberculosis and rifampicin resistance, but its sensitivity is inadequate in patients with paucibacillary disease or HIV. Xpert MTB/RIF Ultra (Xpert Ultra) was developed to overcome this limitation. We compared the diagnostic performance of Xpert...

Serological tests available for the diagnosis of acute Toxoplasma gondii infection have limitations in establishing the temporal diagnosis of acute toxoplasmosis. The present analytical-descriptive investigation comprises of a prospective longitudinal cohort study to search for accurate biomarkers to distinguish acute, early and late convalescent T...

Background In household contact investigations of tuberculosis (TB), a second tuberculin skin test (TST) obtained several weeks after a first negative result consistently identifies individuals that undergo TST conversion. It remains unclear whether this delay in M. tuberculosis infection is related to differences in the infectious exposure, TST bo...

Household contact studies, a mainstay of tuberculosis transmission research, often assume that tuberculosis-infected household contacts of an index case were infected within the household. However, strain genotyping has provided evidence against this assumption. Understanding the household versus community infection dynamic is essential for designi...

Molecular epidemiologic studies have shown that the dynamics of tuberculosis transmission varies geographically. We sought to determine which strains of Mycobacterium tuberculosis (MTB) were infecting household contacts (HHC), and which were causing clusters of tuberculosis (TB) disease in Vitoria-ES, Brazil. A total of 741 households contacts (445...

Rationale: Rapid diagnosis of pulmonary tuberculosis (TB) is critical for timely initiation of treatment and interruption of transmission. Yet, despite recent advances, many patients remain undiagnosed. Culture, usually considered the most sensitive diagnostic method, is sub-optimal for paucibacillary disease. Methods: We evaluated the Totally O...

Obesity is the main causal factor for metabolic syndrome and chronic systemic inflammation, which impacts on immune function and increases susceptibility to pathogens. Here, we investigated the effect of obesity on the outcome of visceral leishmaniasis caused by Leishmaniasis infantum chagasi. C57BL/6 mice fed with high-sugar and butter diet (HSB)...

Supplementary Appendix. Experimental Laboratory methods Technical aspects of TOP TB assayTOP TB assay laboratory methods M. tuberculosis sequencing and genotype nomenclature Supporting Figures Fig A: DNA sequence alignment of M. tuberculosis ponA1Fig B: Sequence representation of five possible 2-PonA genotypes of M. tuberculosis clinical isolate...

Background: The Epistem Genedrive® assay rapidly detects Mycobacterium tuberculosis complex from sputum and is currently available for clinical use. However, the analytical and clinical performance of this test has not been fully evaluated. Methods: The analytical limit of detection (LOD) of the Genedrive PCR amplification was tested with genomi...

Background: A candidate tetravalent dengue vaccine is being assessed in three clinical trials involving more than 35,000 children between the ages of 2 and 16 years in Asian-Pacific and Latin American countries. We report the results of long-term follow-up interim analyses and integrated efficacy analyses. Methods: We are assessing the incidence...

To prepare for a Phase III dengue vaccine efficacy trial, 20 investigational sites were selected for this observational study to identify dengue infections in a closed cohort (N = 3,000 children 9-16 years of age). Of 255 acute febrile episodes experienced by 235 children, 50 (21.3%) were considered serologically probable dengue, and 18 (7.7%) were...

Background: In light of the increasing rate of dengue infections throughout the world despite vector-control measures, several dengue vaccine candidates are in development. Methods: In a phase 3 efficacy trial of a tetravalent dengue vaccine in five Latin American countries where dengue is endemic, we randomly assigned healthy children between t...

Rationale: The degree to which tuberculosis (TB) is transmitted between persons is variable. Identifying the factors that contribute to transmission could provide new opportunities for TB control. Transmission is influenced by host, bacterial and environmental factors. However, distinguishing their individual effects is problematic because measure...