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Sanz, J.

Publications and source records attributed to Sanz, J..

13 recordsLinked to original sources

Development and translational validation of a novel mouse model for allergic rhinitis

Background: Approximately 30% of the North American population are affected by seasonal or perennial rhinitis. Allergens from cats are common triggers of allergic rhinitis. Importantly, cat allergic rhinitis (cat-AR) is a major risk factor for more severe allergic diseases, including asthma. Current therapies rarely achieve full symptom control and development of novel therapeutics is constrained by the lack of physiologically relevant preclinical models. Objective: Establishment of a clinically-informed mouse model of cat allergen exposure in humans. Methods: Controlled human exposure was performed using airborne natural cat dander (CD) in a validated environmental exposure facility. Nasal immune cells and IgE concentrations in serum and nasal samples were assessed. In mice, we established a 14-day intermittent intranasal sensitization and challenge protocol using the same CD allergens. Clinical signs in mice were objectively quantified using AI-based video detection. Cellular changes in the nose were assessed with level-specific, spatial resolution. Lastly, systemic sensitization was confirmed through serum IgE and intradermal ear challenge. Measurements and Main Results: Following CD exposure, cat-allergic participants displayed increased nasal symptoms and eosinophil influx. CD-sensitized mice recapitulated key clinical features, including increased nasal rubbing, elevated nasal immune cell infiltration, and systemic sensitization. Importantly, spatial investigation of the cellular changes revealed major changes in the turbinate and olfactory regions of the nose. Conclusions: This novel mouse model provides a translationally valuable platform for investigating local and systemic mechanisms of cat-AR. It will serve for mechanistic and therapeutic evaluations with the goal of improving clinical translation and therapeutic precision.

immunology↗

A Novel Secretome Rewrites the Immune Response in Viral Acute Respiratory Distress Syndrome

BackgroundHyperinflammatory syndromes such as viral acute respiratory distress syndrome (ARDS) demand immunotherapies that are safe and effective at suppressing cytokine storm. As a novel treatment for ARDS, PRS CK STORM is proposed as a next-generation cell-free secretome derived from co-cultures of M2 macrophages and mesenchymal stromal cells. MethodsWe performed a double-blind, randomized controlled trial to test the effects of PRS CK STORM in K18-hACE2 transgenic mice infected intranasally with 105 PFU of SARS-CoV-2 BE.1.1. This was complemented by a mechanistic analysis of this secretome using transcriptomic and COX2 enzymatic activity studies, as well as a compositional analysis of its proteomic and miRNA profile. ResultsIn a lethal SARS-CoV-2 ARDS mouse model, PRS CK STORM significantly improved lung histopathology to a degree on par with corticosteroids, while stimulating angiogenesis in damaged lung tissue. Early and late cytokine profiling showed marked reductions in IFN-{gamma}. In response to PRS CK STORM treatment, transcriptomic analyses in inflamed macrophages revealed robust downregulation of key proinflammatory drivers (MyD88, TRAF6, IKK2, NF-{kappa}B, COX2). In vitro enzymatic assays confirmed potent, dose-dependent inhibition of COX2, with high inter-batch reproducibility. A compositional analysis revealed this secretome to be rich in anti-inflammatory miRNAs, immune-modulating proteins, and regenerative factors. ConclusionsPRS CK STORM operates as a multi-target immune recalibrator, enabling broad downregulation of pathological inflammation while promoting tissue repair. Its off-the-shelf, GMP-manufactured format ensures reproducibility and scalability, offering a novel resolution pharmacology approach for cytokine storm syndromes originated from ARDS and beyond.

immunology↗

Regulation of B cell tolerance and autoimmunity by miR-130b

Breakdown of B cell tolerance is a central feature of autoimmune diseases, yet the molecular mechanisms underlying the female predominance of these diseases remain unclear. Here, we identified miR-130b as an essential component of a miRNA network, defined by the GUGCA seed motif, that regulates central B cell tolerance. Elevated miR-130b levels impaired tolerance by promoting the survival of immature B cells upon B cell antigen receptor engagement. This network converged on the estrogen receptor pathway through downregulation of Esr1 and Pten. Genetic ablation of Esr1 in immature B cells was sufficient to compromise central B cell tolerance in females, but not in males, revealing an unrecognized role for ER in this process. In males, Esr1 deficiency reduced bone marrow B cell numbers, whereas in females, B cell numbers were preserved, with a greater proportion of cells displaying lower surface CD19 levels. Transcriptomic analysis revealed sex-specific genetic programs characterized by defective B cell development and skewed immunoglobulin gene usage in males, and increased PI3K-AKT signaling in females. In females, this molecular rewiring compensated for developmental defects, but also attenuated central tolerance mechanisms, allowing the escape of autoreactive B cells to the periphery. In patients with multiple sclerosis, elevated levels of miR-130b in circulating vesicles correlated with more severe disease, including increased formation of new demyelinating lesions, cognitive decline, and neurodegeneration. Together, our findings identify a sex-specific ER-dependent checkpoint in B cell tolerance controlled by a seed-driven miRNA network, providing a mechanistic framework for female predisposition to autoimmunity.

immunology↗

BCG vaccination impacts the epigenetic landscape of progenitor cells in human bone marrow

While the Bacille-Calmette-Guerin (BCG) vaccine is used to prevent tuberculosis, it also offers protection against a diverse range of non-mycobacterial infections. However, the underlying protective mechanisms in humans are not yet fully understood. Here, we surveyed at single-cell resolution the gene expression and chromatin landscape of human bone marrow, aspirated before and 90 days after BCG vaccination or placebo administration. We show that BCG vaccination significantly alters both the gene expression and epigenetic profiles of human hematopoietic stem and progenitor cells (HSPCs). Changes in gene expression occur primarily on the most uncommitted stem cells and are reflective of a persistent myeloid bias. In contrast, BCG-induced changes in chromatin accessibility are most prevalent within differentiated progenitor cells at sites influenced by Kruppel-like factor (KLF)/SP and EGR transcription factors (TFs). These TFs are also activated in the most uncommitted stem cells, indicating that activated TFs, which drive persistent changes in HSC gene expression, likely also drive chromatin dynamics appearing within downstream progenitor cells. This perspective contests the prevailing notion that epigenetic modifications linked to innate immune memory transfer directly from stem cells to their differentiated derivatives. Finally, we show that alterations in gene expression and chromatin accessibility in HSPCs due to BCG vaccination were highly correlated (r>0.8) with the IL-1{beta} secretion capacity of paired PBMCs upon secondary immune challenge. Overall, our findings shed light on BCG vaccinations profound and lasting effects on HSPCs and its influence on innate immune responses.

immunology↗

Maintenance of cell wall remodeling and vesicle production are connected in Mycobacterium tuberculosis

Pathogenic and nonpathogenic mycobacteria secrete extracellular vesicles (EVs) under various conditions. EVs produced by Mycobacterium tuberculosis (Mtb) have raised significant interest for their potential in cell communication, nutrient acquisition, and immune evasion. However, the relevance of vesicle secretion during tuberculosis infection remains unknown due to the limited understanding of mycobacterial vesicle biogenesis. We have previously shown that a transposon mutant in the LCP-related gene virR (virRmut) manifested a strong attenuated phenotype during experimental macrophage and murine infections, concomitant to enhanced vesicle release. In this study, we aimed to understand the role of VirR in the vesicle production process in Mtb. We employ genetic, transcriptional, proteomics, ultrastructural and biochemical methods to investigate the underlying processes explaining the enhanced vesiculogenesis phenomenon observed in the virRmut. Our results establish that VirR is critical to sustain proper cell permeability via regulation of cell envelope remodeling possibly through the interaction with similar cell envelope proteins, which control the link between peptidoglycan and arabinogalactan. These findings advance our understanding of mycobacterial extracellular vesicle biogenesis and suggest that these set of proteins could be attractive targets for therapeutic intervention.

microbiology↗

ART duration and immunometabolic state determine efficacy of DC-based treatment restoring functional HIV- specific CD8+ T cells in Chronic PLWH.

Dysfunction of CD8+ T cells in people living with HIV-1 (PLWH) receiving anti-retroviral therapy (ART) has restricted the efficacy of dendritic cell (DC)-based immunotherapies against HIV-1. Heterogeneous immune exhaustion and metabolic states of CD8+ T cells might differentially associate with dysfunction. However, specific parameters associated to functional restoration of CD8+ T cells after DC treatment have not been investigated in detail. Here, we studied the association of ART duration with memory subsets, exhaustion and metabolic profiles of CD8+ T cells from PLWH and improvement of polyfunctional and effector HIV-1 specific responses after stimulation with Gag-adjuvant-primed DC. HIV-1-specific CD8+ T cell responses from a larger proportion PLWH on ART for more than 10 years (LT-ARTp) improved polyfunctionality and capacity to eliminate autologous p24+ infected CD4+ T cells in vitro. In contrast, CD8+ T cells from PLWH on ART for less than a decade (ST-ARTp) were less responsive to DC treatment and functional improvement was limited in this group. This was associated with lower frequencies of central memory CD8+ T cells, increased co-expression of PD1 and TIGIT and reduced mitochondrial respiration and glycolytic induction upon TCR activation. In contrast, CD8+ T cells from LT-ARTp showed increased frequencies of TIM3+PD1-cells and preserved induction of glycolysis. Treatment of dysfunctional CD8+ T cells from ST-ARTp with combined anti-PD1 and anti-TIGIT antibodies plus a glycolysis promoting drug restored their ability to eliminate infected CD4+ T cells. Together, our study identifies specific immunometabolic parameters for different PLWH subgroups potentially useful for future personalized DC-based HIV-1 vaccines.

immunology↗

TAILORED DC INDUCE PROTECTIVE HIV-1 SPECIFIC POLYFUNCTIONAL CD8+ T CELLS IN THE LYMPHOID TISSUE FROM HUMANIZED BLT MICE

Effective function of CD8+ T cells and enhanced innate activation of dendritic cells (DC) in response to HIV-1 is linked to protective antiviral immunity in controllers. Manipulation of DC targeting the master regulator TANK-binding Kinase 1 (TBK1) might be useful to acquire controller-like properties. Here, we evaluated the impact of TBK1-primed DC inducing protective CD8+ T cell responses in lymphoid tissue and peripheral blood and their association with reduced HIV-1 disease progression in vivo in the humanized bone marrow, liver and thymus (hBLT) mouse model. A higher proportion of hBLT-mice vaccinated with TBK1-primed DC exhibited less severe CD4+ T cell depletion following HIV-1 infection compared to control groups. This was associated with infiltration of CD8+ T cells in the white pulp from the spleen, reduced spread of infected p24+ cells to secondary lymphoid organs and with preserved abilities of CD8+ T cells from the spleen and blood of vaccinated animals to induce specific polyfunctional responses upon antigen stimulation. Therefore, TBK1-primed DC might be an useful tool for subsequent vaccine studies. Author summaryEmulating protective immunological characteristics from individuals capable of spontaneously controlling HIV-1 infection might be useful for the development of a protective vaccine. Enhanced function of dendritic cells (DC) in these HIV-1 controllers depends on the activation of TANK-binding Kinase 1 (TBK1) and might associate with protective T cells. Our study evaluated the ability of DCs trained through TBK1 activation inducing protective adaptive immune responses against HIV-1 and reducing disease progression in vivo, using a humanized mouse model. Our data indicate that mice vaccinated with tailored DC exhibit delayed disease progression, increased induction of protective CD8+ T lymphocyte subsets in the lymphoid tissue and blood upon antigen recognition. Therefore, trained-DC might be an useful tool for future HIV-1 vaccine designs.

immunology↗

Social history and exposure to pathogen signals modulate social status effects on gene regulation in rhesus macaques

Social experiences are an important predictor of disease susceptibility and survival in humans and other social mammals. Chronic social stress is thought to generate a pro-inflammatory state characterized by elevated antibacterial defenses and reduced investment in antiviral defense. Here, we manipulated long-term social status in female rhesus macaques to show that social subordination alters the gene expression response to ex vivo bacterial and viral challenge. As predicted by current models, bacterial lipopolysaccharide polarizes the immune response such that low status corresponds to higher expression of genes in NF-{kappa}B-dependent pro-inflammatory pathways and lower expression of genes involved in the antiviral response and type I interferon (IFN) signaling. Counter to predictions, however, low status drives more exaggerated expression of both NF-{kappa}B and IFN-associated genes after cells are exposed to the viral mimic Gardiquimod. Status-driven gene expression patterns are not only linked to social status at the time of sampling, but also to social history (i.e., past social status), especially in unstimulated cells. However, for a subset of genes, we observed interaction effects in which females who fell in rank were more strongly affected by current social status than those who climbed the social hierarchy. Together, our results indicate that the effects of social status on immune cell gene expression depend on pathogen exposure, pathogen type, and social history - in support of social experience-mediated biological embedding in adulthood, even in the conventionally memory-less innate immune system.

genomics↗

Natural selection contributed to immunological differences between human hunter-gatherers and agriculturalists

The shift from a hunter-gatherer (HG) to an agricultural (AG) mode of subsistence is believed to have been associated with profound changes in the burden and diversity of pathogens across human populations. Yet, the extent to which the advent of agriculture may have impacted the evolution of the human immune system remains unknown. Here we present a comparative study of variation in the transcriptional responses of peripheral blood mononuclear cells to bacterial and viral stimuli between Batwa rainforest hunter-gatherers and Bakiga agriculturalists from Uganda. We observed increased divergence between hunter-gatherers and agriculturalists in the transcriptional response to viruses compared to that for bacterial stimuli. We demonstrate that a significant fraction of these transcriptional differences are under genetic control, and we show that positive natural selection has helped to shape population differences in immune regulation. Across the set of genetic variants underlying inter-population immune response differences, however, the signatures of positive selection were disproportionately observed in the rainforest hunter-gatherers. This result is counter to expectations based on the popularized notion that shifts in pathogen exposure due to the advent of agriculture imposed radically heightened selective pressures in agriculturalist populations.

evolutionary biology↗

Social status alters chromatin accessibility and the gene regulatory response to glucocorticoid stimulation in rhesus macaques

Low social status is an important predictor of disease susceptibility and mortality risk in humans and other social mammals. These effects are thought to stem in part from dysregulation of the glucocorticoid (GC)-mediated stress response. However, the molecular mechanisms that connect low social status and GC dysregulation to downstream health outcomes remain elusive. Here, we used an in vitro glucocorticoid challenge to investigate the consequences of experimentally manipulated social status (i.e., dominance rank) for immune cell gene regulation in female rhesus macaques, using paired control and GC-treated peripheral blood mononuclear cell samples. We show that social status not only influences immune cell gene expression, but also chromatin accessibility at hundreds of regions in the genome. Social status effects on gene expression were less pronounced following GC treatment than under control conditions. In contrast, social status effects on chromatin accessibility were stable across conditions, resulting in an attenuated relationship between social status, chromatin accessibility, and gene expression post-GC exposure. Regions that were more accessible in high status animals and regions that become more accessible following GC treatment were enriched for a highly concordant set of transcription factor binding motifs, including motifs for the glucocorticoid receptor co-factor AP-1. Together, our findings support the hypothesis that social status alters the dynamics of GC-mediated gene regulation, and identify chromatin accessibility as a mechanism involved in social stress-driven GC resistance. More broadly, they emphasize the context-dependent nature of social status effects on gene regulation and implicate epigenetic remodeling of chromatin accessibility as a contributing factor.

genomics↗

Projecting social contact matrices to different demographic structures

The modeling of large-scale communicable epidemics has greatly benefited in the last years from the increasing availability of highly detailed data. Particularly, in order to achieve quantitative descriptions of the evolution of epidemics, contact networks and mixing patterns are key. These heterogeneous patterns depend on several factors such as location, socioeconomic conditions, time, and age. This last factor has been shown to encapsulate a large fraction of the observed inter-individual variation in contact patterns, an observation validated by different measurements of age-dependent contact matrices. Recently, several works have studied how to project those matrices to areas where empiric data is not available. However, the dependence of contact matrices on demographic structures and their time evolution has been largely neglected. In this work, we tackle the problem of how to transform an empirical contact matrix that has been obtained for a given demographic structure into a different contact matrix that is compatible with a different demography. The methodology discussed here allows extrapolating a contact structure measured in a particular area to any other whose demographic structure is known, as well as to obtain the time evolution of contact matrices as a function of the demographic dynamics of the populations they refer to. To quantify the effect of considering time-dynamics of contact patterns on disease modeling, we implemented a Susceptible-Exposed-Infected-Recovered (SEIR) model on 16 different countries and evaluated the impact of neglecting the temporal evolution of mixing patterns. Our results show that simulated disease incidence rates, both at the aggregated and age-specific levels, are significantly dependent on contact structures variation driven by demographic evolution. The present work opens the path to eliminate technical biases from model-based impact evaluations of future epidemic threats and warns against the use of contact matrices to model diseases without correcting for demographic evolution or geographic variations.\n\nAuthor summaryLarge scale epidemic outbreaks represent an ever increasing threat to humankind. In order to anticipate eventual pandemics, mathematical modeling should not only have the capacity to model in real time an ongoing disease, but also to predict the evolution of potential outbreaks in different locations and times. To this end, computational frameworks need to incorporate, among other ingredients, realistic contact patterns into the models. This not only implies anticipating the demographic structure of the populations under study, but also understanding how demographic evolution reshapes social mixing patterns along time. Here we present a mathematical framework to solve this problem and test our modeling approach on 16 different empirical contact matrices. We also evaluate the impact of an eventual future outbreak by simulating a SEIR scenario in the countries analyzed. Our results show that using outdated or imported contact matrices that do not take into account demographic structure or its evolution can lead to largely misleading conclusions.

epidemiology↗

Design principles for TB vaccines’ clinical trials based on spreading dynamics

Tuberculosis (TB) is one of the most complex diseases from the perspective of mathematical epidemiology. Individuals recently infected with the bacillus Mycobacterium tuberculosis can either develop TB directly in a matter of several weeks, or enter into an asymptomatic latent TB infection state (LTBI) that only occasionally derives into active disease, sometimes even decades after the infection event. The possible interruptions that a vaccine might provoke on these two mechanisms are indistinguishable in phase II clinical trials. In this work, we present a new methodology that allows differentiating vaccines that slow down the progression to disease from vaccines that prevent it. By introducing a stochastic framework for simulating synthetic clinical trials based on transmission models, we show how the method proposed here contributes both to reduce uncertainty in vaccine characterization and impact forecasts as well as to assist the design of clinical trials, improving their probabilities of success.

epidemiology↗

A data-driven model for the assessment of age-dependent patterns of Tuberculosis burden and impact evaluation of novel vaccines.

In the case of tuberculosis (TB), the capabilities of epidemic models to produce quantitatively robust forecasts are limited by multiple hindrances. Among these, understanding the complex relationship between disease epidemiology and populations' age structure has been highlighted as one of the most relevant. TB dynamics depends on age in multiple ways, some of which are traditionally simplified in the literature. That is the case of the heterogeneities in contact intensity among different age-strata that are common to all air-borne diseases, but still typically neglected in the TB case. Furthermore, whilst demographic structures of many countries are rapidly aging, demographic dynamics is pervasively ignored when modeling TB spreading. In this work, we present a TB transmission model that incorporates country-specific demographic prospects and empirical contact data around a data-driven description of TB dynamics. Using our model, we find that the inclusion of demographic dynamics is followed by an increase in the burden levels prospected for the next decades in the areas of the world that are most hit by the disease nowadays. Similarly, we show that considering realistic patterns of contacts among individuals in different age-strata reshapes the transmission patterns reproduced by the models, a result with potential implications for the design of age-focused epidemiological interventions.\n\nSignificance StatementEven though tuberculosis (TB) is acknowledged as a strongly age-dependent disease, it remains unclear how TB epidemics would react, in the following decades, to the generalized aging that human populations are experiencing worldwide. This situation is partly caused by the limitations of current transmission models at describing the relationship between demography and TB transmission. Here, we present a data-driven epidemiological model that, unlike previous approaches, explicitly contemplates relevant aspects of the coupling between agestructure and TB dynamics, such as demographic evolution and contact heterogeneities. Using our model, we identify substantial biases in epidemiological forecasts rooted in an inadequate description of these aspects, both at the level of aggregated incidence and mortality rates and their distribution across age-strata.

epidemiology↗