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Duque, C.

Publications and source records attributed to Duque, C..

6 recordsLinked to original sources

Maternal Trypanosoma cruzi infection is associated with significant placental remodeling regardless of vertical transmission

Chagas disease is a major protozoan infection in the Americas, causing approximately 12,000 deaths each year. It is caused by Trypanosoma cruzi, and can be transmitted transplacentally, leading to congenital Chagas disease, a silent route that carries substantial risk for newborns. However, the mechanisms underlying congenital Chagas transmission are poorly understood. Here, we evaluated whether T. cruzi infection alters the placental microenvironment and systemic physiology, and whether such alterations are associated with congenital transmission. Integrating bulk RNA sequencing, proteomics, and spatial transcriptomics, we show that T. cruzi infection elicits profound molecular remodeling in both placenta and peripheral blood, regardless of transmission status. Transmitting mothers exhibit a distinct transcriptional signature enriched for inflammatory and tissue-remodeling pathways. Notably, peripheral blood profiles mirrored some placental alterations. A panel of inflammatory serum proteins showed promising predictive potential for transmission risk, with implications for prenatal monitoring. Together, these findings support a fundamental shift in the conceptual framework of congenital Chagas disease, from a transmission-centered model to one that recognizes infection-driven placental damage as a pathological spectrum and identifies peripheral blood as a promising, non-invasive source of predictive biomarkers for adverse pregnancy outcomes. This framework motivates the further application of single-cell-resolution approaches to refine models of congenital Chagas pathogenesis and the systematic analysis of maternal peripheral blood during pregnancy to enable early risk stratification and the development of predictive tools for adverse outcomes.

molecular biology↗

Clinical Trypanosoma cruzi isolates share a common antigen repertoire that is absent from culture adapted strains

BackgroundTrypanosoma cruzi causes Chagas disease, a poorly understood and clinically heterogeneous disease. Recent work has demonstrated that parasites adapted to laboratory conditions are genomically variable, but little is known of the extent of genomic diversity from clinically isolated specimens. MethodsIn this retrospective observational genomic study, we isolated 15 T. cruzi specimens from three clinical studies of Chagas disease, representing different clinical contexts. We sequenced the genome of each strain and used single nucleotide variant (SNV) based analyses to estimate parasite genetic lineage, genomic population structure, regions of copy number plasticity, and to identify gene conversion events. In addition, we generated and annotated whole genome assemblies of each isolate. From these assemblies, we compared the repertoires of genes encoding for highly virulent and variable proteins that have been implicated in disease pathogenesis. FindingsWe identified parasites from two genetic lineages in this collection of clinical isolates. Our analysis revealed evidence of genomic instability. Diversity-generating copy number variation was statistically enriched in regions encoding the virulence-associated multigene families, while diversity-eliminating gene conversion events were enriched in regions depleted of multigene family members. We also discovered a set of multigene family members that is present in all of the clinically isolated parasite genomes and absent from all of the lab adapted strains, regardless of parasite lineage. Multigene family repertoires were more conserved among field isolated specimens of the same genetic lineage than among culture adapted strains of the same genetic type. InterpretationThis study provides whole genome sequencing data for TcV parasites isolated from naturally infected human patients with Chagas disease for the first time. Our analysis of these genomes revealed substantial genomic instability, suggesting the parasite undergoes genomic change in response to the pressures imposed by the host environment. Moreover, we observed a set of virulence-associated genes that are present exclusively within clinical isolates and absent from lab-adapted strains, indicating a potential role for these genes in parasite survival in natural hosts. These findings highlight the limitations of genetic studies focused exclusively on lab-adapted parasite strains and provide insight into the genomic features of T. cruzi that are likely to be important for clinical infection.

microbiology↗

B cell-mediated antigen presentation promotes adverse cardiac remodeling in chronic heart failure

The cardio-splenic axis is a promising therapeutic target in ischemic heart failure (HF), but splenic-cardiac interactions after myocardial infarction (MI) are poorly understood. Here, we show that splenic follicular B cells drive ischemic HF via MHC class II-mediated antigen presentation. Transfer of splenic B cells from mice with ischemic HF induced adverse cardiac remodeling and modulated myocardial T-cells in naive recipients. Single-cell RNA sequencing of mouse and human post-MI B cells revealed upregulation of antigen-presentation related pathways. Mass spectrometry of the MHC II peptidome demonstrated enrichment of cardiac-derived peptides in MHC II molecules of splenic B cells from ischemic HF mice. B cell-specific deletion of MHC II suppressed adverse cardiac remodeling after adoptive transfer of post-MI splenic B cells. These results broaden our understanding of B-lymphocyte biology and point towards MHC II-mediated signaling in B-cells as a novel therapeutic target in ischemic HF.

immunology↗

Immunologic changes are detectable in the peripheral blood transcriptome of clinically asymptomatic Chagas cardiomyopathy patients

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is a neglected parasitic disease that affects approximately 6 million individuals worldwide. Of those infected, 20-30% will go on to develop chronic Chagas cardiomyopathy (CCC), and ultimately many of these individuals will progress to advanced heart failure. The mechanism by which this progression occurs is poorly understood, as few studies have focused on early CCC. In this study, we sought to understand the physiologic changes associated with T. cruzi infection and the development of CCC. We analyzed gene expression in the peripheral blood of asymptomatic Chagas patients with early structural heart disease, Chagas patients without any signs or symptoms of disease, and Chagas-negative patients with and without early structural heart disease. Our analysis shows that early CCC was associated with a downregulation of various peripheral immune response genes, with gene expression changes suggestive of reduced antigen presentation and T cell activation. Notably, these genes and processes were distinct from those of early cardiomyopathy in Chagas-negative patients, suggesting that the processes mediating CCC may be unique from those mediating progression to other cardiomyopathies. This work highlights the importance of the immune response in early CCC, providing insight into the early pathogenesis of this disease. The changes we have identified may serve as biomarkers of progression and could inform strategies for the treatment of CCC in its early stages, before significant cardiac damage has occurred.

immunology↗

B cells occupy a unique, dynamic, biological niche within the human myocardium

IntroductionGrowing evidence from animal models indicates that the myocardium hosts a population of B cells that play a role in the development of cardiomyopathy. However, there is minimal data on human myocardial B cells in the context of cardiomyopathy. MethodsWe integrated single-cell and single-nuclei datasets from 45 healthy human hearts, 70 hearts with dilated cardiomyopathy (DCM), and 8 hearts with Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC). Interactions between B cells and other cell types were investigated using the CellChat Package. Differential gene expression analysis comparing B cells across conditions was performed using DESeq2. Pathway analysis was performed using Ingenuity, KEGG, and GO pathways analysis. ResultsWe identified 1,100 B cells, including naive B cells and plasma cells. B cells showed an extensive network of interactions within the healthy myocardium that included outgoing signaling to macrophages, T cells, endothelial cells, and pericytes, and incoming signaling from endothelial cells, pericytes, and fibroblasts. This niche relied on ECM-receptor, contact, and paracrine interaction; and changed significantly in the context of cardiomyopathy, displaying disease-specific features. Differential gene expression analysis showed that in the context of DCM both naive and plasma B cells upregulated several pathways related to immune activation, including upregulation of oxidative phosphorylation, upregulation of leukocyte extravasation, and, in naive B cells, antigen presentation. DiscussionThe human myocardium contains naive B cells and plasma cells, integrated into a diverse and dynamic niche that has distinctive features in healthy myocardium, DCM, and ARVC. Naive myocardial-associated B cells likely contribute to the pathogenesis of human DCM.

immunology↗

The need to harmonize insecticide resistance testing: methodology, intensity concentrations and molecular mechanisms evaluated in Aedes aegypti populations in Central America and Hispaniola

BackgroundThe Zika AIRS Project, a USAID-funded initiative worked across the Latin America and Caribbean regions from 2016 to 2019, as an emergency to contain the spread of the Zika virus. All entomological records in the target countries showed wide distribution and high abundance of Aedes aegypti populations, however the susceptibility profiles of these insects to insecticides commonly employed by vector control campaigns were in most cases incomplete or inexistent. In close collaboration with the Ministries of Health of individual countries, Zika-AIRS teams conducted insecticide susceptibility testing of an array of insecticides in A. aegypti populations of each country. Procedures applied met the standard international protocols instructed by the World Health Organization and Centers for Disease Control and Prevention. Methodology and main findingsThe insecticides tested were selected under categories such as pyrethroids, organophosphates and carbamate. Results showed A. aegypti populations displaying high and widely distributed resistance to all pyrethroids across countries, tolerance to organophosphates and full susceptibility to a carbamate. Key inconsistencies between testing methods are presented and discussed. Additionally, four kdr mutations were analyzed to detect molecular mechanisms of insecticide resistance. The screening for kdr mutations suggested the widespread nature of V1016I mutation, linked to pyrethroid resistance in A. aegypti populations distributed and sampled in the above mentioned regions. Conclusions and perspectivesThis multi-country study contributes with updated information to the public health decision-makers across Central America and the Caribbean. This study provided training and established technical networks for more effective and sustainable insecticide surveillance programs. Most but not all records of insecticide resistance in A. aegypti were consistent between methodologies, thus inconsistent issues are discussed here to call for further improvement in procedures and convey more practical guidelines for surveillance teams in countries where Aedes-borne diseases are endemic. Author summaryAt the forefront of the fight against arboviruses transmission is the insecticide-based vector control. All countries in the Latin American and Caribbean region invest valuable resources from their limited budget to acquire and implement insecticide-based tools, with non-existent or weak insecticide resistance monitoring programs. Hence, the USAID-funded Zika AIRS Project (ZAP) collaborated with the Ministries of Health of multiple countries to update the profile of susceptibility to insecticides in Aedes aegypti populations. We found widespread resistance to pyrethroid and organophosphate insecticides, which account to almost 100% of the products available to control adult mosquitoes. As we used both of World Health Organization and Centers for Disease Control and Prevention standard methods, we found many similarities and some inconsistencies in the susceptibility profiles obtained for the very same vector populations. Additionally, we obtained insight on potential molecular mechanisms of resistance across the countries, finding the kdr mutation V1016I possibly involved in loss of susceptibility. This study is the biggest cross-country update of insecticide resistance for Aedes aegypti in years, and it should be used as evidence for improving the selection of insecticides in these countries and a call for further support to maintain insecticide resistance monitoring programs.

ecology↗