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Pugliese, A.

Publications and source records attributed to Pugliese, A..

8 recordsLinked to original sources

Modelling assessment of the different paths of between-farm transmission of avian influenza HPAI in Northern Italy in 2021--2022

We propose a stochastic epidemic model to describe the spread of avian influenza in a network of poultry farms. We consider three main paths of infection transmission between poultry farms: from nearby farms, mainly through airborne diffusion; from farms belonging to the same company, through shared veterinarians, forage providers and similar; from undetected small farms or wildlife. From the parameter estimation, based on a modified Expectation-Maximization algorithm, we infer that approximately 63% of the farms were infected from nearby ones, with an infection force declining with distance; of these, more than one third belonged to the same company of the estimated infector. About 20% were infected from premises belonging to the same company but farther away than the distance threshold of 2 km; the remaining ones from wildlife or unidentified sources. These estimates have been validated by a comparison with genetic data, available for a subset of the farms: the genetic distance between two farms identified, with high probability, as an infector-infectee pair is much lower than between random pairs. These results may help in the implementation of tailored prevention and control measures for future outbreaks.

genetics↗

Harmine Plus Exendin-4 Enhances Remission of Recent-Onset Type 1 Diabetes Following Anti-CD3 Therapy

Type 1 diabetes (T1D) results from autoimmune destruction of pancreatic {beta}-cells. While anti-CD3 therapy can delay disease progression and preserve residual {beta}-cell function, disease reversal will likely require both immune modulation and {beta}-cell regeneration. We found that the combination of harmine and exendin-4 (H+E) reduced inflammation-induced human {beta}-cell apoptosis, suppressed cytokine signaling and immunogenicity pathways, and improved {beta}-cell function. Although H+E alone did not reverse diabetes in NOD mice, low-dose anti-CD3 followed by H+E normalized blood glucose, increased insulin levels, improved glucose tolerance, expanded {beta}-cell mass, and enhanced diabetes remission. These effects were associated with reduced pro-inflammatory T-cell responses, increased regulatory T cells, and greater expression of exhaustion-related T-cell markers, without broad lymphocyte depletion. Similar immunomodulatory effects were observed in activated human PBMCs. Transcriptomic analyses identified the lncRNA SNHG6 as a key mediator of H+E action; SNHG6 protected {beta}-cells from cytokine-induced stress, apoptosis, and immunogenicity. Together, these findings demonstrate that H+E promotes {beta}-cell recovery and resilience while reducing {beta}-cell immunogenicity, enabling remission of recent-onset T1D when combined with anti-CD3 therapy. SNHG6 emerges as a novel regulator of {beta}-cell protection during inflammation.

cell biology↗

Coxsackievirus infection induces direct pancreatic β-cell killing but poor anti-viral CD8+ T-cell responses

Coxsackievirus B (CVB) infection of pancreatic {beta} cells is associated with {beta}-cell autoimmunity. We investigated how CVB impacts human {beta} cells and anti-CVB T-cell responses. {beta} cells were efficiently infected by CVB in vitro, downregulated HLA Class I and presented few, selected HLA-bound viral peptides. Circulating CD8+ T cells from CVB-seropositive individuals recognized only a fraction of these peptides, and only another sub-fraction was targeted by effector/memory T cells that expressed the exhaustion marker PD-1. T cells recognizing a CVB epitope cross-reacted with the {beta}-cell antigen GAD. Infected {beta} cells, which formed filopodia to propagate infection, were more efficiently killed by CVB than by CVB-reactive T cells. Thus, our in-vitro and ex-vivo data highlight limited T-cell responses to CVB, supporting the rationale for CVB vaccination trials for type 1 diabetes prevention. CD8+ T cells recognizing structural and non-structural CVB epitopes provide biomarkers to differentially follow response to infection and vaccination.

immunology↗

Early adversity changes the economic conditions of structural brain network organisation

Early adversity can change educational, cognitive, and mental health outcomes. However, the neural processes through which early adversity exerts these effects remain largely unknown. We used generative network modelling of the mouse connectome to test whether unpredictable postnatal stress shifts the constraints that govern the formation of the structural connectome. A model that trades off the wiring cost of long-distance connections with topological homophily (i.e. links between regions with shared neighbours) generated simulations that replicate the organisation of the rodent connectome. The imposition of early life adversity significantly shifted the best-performing parameter combinations toward zero, heightening the stochastic nature of the generative process. Put simply, unpredictable postnatal stress changes the economic constraints that shape network formation, introducing greater randomness into the structural development of the brain. While this change may constrain the development of cognitive abilities, it could also reflect an adaptive mechanism. In other words, neural development could harness heightened stochasticity to make networks more robust to perturbation, thereby facilitating effective responses to future threats and challenges. Significance statementChildren who experience adversity early in life - such as chronic poverty or abuse - show numerous neural differences that are linked to poorer cognition and mental health later in life. To effectively mitigate the burden of adversity, it is critical to identify how these differences arise. In this paper, we use computational modelling to test whether growing up in an impoverished and unpredictable environment changes the development of structural connections in the mouse brain. We found that early adversity appears to introduce more stochasticity in the formation of neural architecture. Our findings point to a potential mechanism for how early adversity could change the course of child development.

neuroscience↗

ACE2 and SARS-CoV-2 Expression in the Normal and COVID-19 Pancreas

Diabetes is associated with increased mortality from Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Given literature suggesting a potential association between SARS-CoV-2 infection and diabetes induction, we examined pancreatic expression of the key molecule for SARS-CoV-2 infection of cells, angiotensin-converting enzyme-2 (ACE2). Specifically, we analyzed five public scRNAseq pancreas datasets and performed fluorescence in situ hybridization, Western blotting, and immunolocalization for ACE2 with extensive reagent validation on normal human pancreatic tissues across the lifespan, as well as those from coronavirus disease 2019 (COVID-19) patients. These in silico and ex vivo analyses demonstrated pancreatic expression of ACE2 is prominent in pancreatic ductal epithelium and the microvasculature, with rare endocrine cell expression of this molecule. Pancreata from COVID-19 patients demonstrated multiple thrombotic lesions with SARS-CoV-2 nucleocapsid protein expression primarily limited to ducts. SARS-CoV-2 infection of pancreatic endocrine cells, via ACE2, appears an unlikely central pathogenic feature of COVID-19 as it relates to diabetes.

pathology↗

Sustained Release of IL-2 Using an Injectable Hydrogel Prevents Autoimmune Diabetes

Interleukin 2 (IL-2) is a promising therapy for autoimmune type 1 diabetes (T1D), but the short half-life in vivo (less than 6 minutes) limits effective tissue exposure to IL-2. Tissue exposure is required for the tolerogenic effects of IL-2. We have developed an injectable hydrogel that incorporates heparin polymers to enable the sustained release of IL-2. This platform uses clinical grade and commercially available materials, including collagen, hyaluronan, and heparin, to deliver IL-2 by slowly degrading and releasing IL-2 over a two-week period in vivo. We find that heparin potentiates the activity of IL-2 and IL-2-mediated expansion of Foxp3+ regulatory T cell (Treg). Hydrogel-mediated IL-2 release showed a reduction of CD4+ and CD8+ T cells and an increase of FoxP3+ Treg in the lymph nodes of injected mice. Moreover, in the Non-Obese Diabetic (NOD) mouse model of T1D once-weekly administration of IL-2 hydrogels prevented diabetes onset as efficiently as 3x weekly repeated injections of soluble IL-2. Together these data suggest that heparin-containing hydrogels may have benefit in delivering low-dose IL-2 and promoting immune tolerance in autoimmune diabetes.

immunology↗

Non-canonical glutamate signaling in a genetic model of migraine with aura

Migraine with aura is an extremely common but poorly understood sensory circuit disorder. Monogenic models allow an opportunity to understand its mechanisms, in particular because the migraine aura is associated with spreading depolarizations that can be measured physiologically. Using fluorescent glutamate imaging in awake mice carrying a familial hemiplegic migraine type 2 mutation, we recorded previously undescribed spontaneous plumes of glutamate signaling that anatomically overlapped with reduced density of GLT-1a positive astrocyte processes. These events could be mimicked in wild-type animals by inhibition of glutamate clearance, which we show to be slower during sensory processing in FHM2 carriers. Plumes depended on calcium mediated vesicular release from neurons, but not action potentials. Importantly, a rise in both basal glutamate and plume frequency predicted the onset of spreading depolarization in WT and FHM2 animals, providing a novel mechanism in migraine with aura and by extension the many other neurological disorders where spreading depolarizations occur.

neuroscience↗

Detection of enterovirus protein and RNA in multiple tissues from nPOD organ donors with type 1 diabetes

Epidemiological studies have shown an association between enterovirus (EV) infections and type 1 diabetes (T1D), and EV protein has been detected in the pancreatic islets of T1D patients. Here we correlated the detection of EVs in lymphoid tissues (spleen and pancreatic lymph nodes) and small intestinal mucosa to the virus detection in the pancreas of T1D, autoantibody-positive (aab+) and non-diabetic control organ donors of the Network for Pancreatic Organ Donors with Diabetes (nPOD) study. Formalin-fixed paraffin-embedded tissue samples were screened for insulin and EV protein using immunohistochemistry, and frozen tissue for EV genome using RT-PCR. The presence of EV protein in the pancreatic islets correlated with the presence of insulin-positive cells. Altogether 62 % of T1D and aab+ donors were positive for EV protein in pancreatic islets (only insulin-positive donors included), 40 % in duodenum and 32 % in spleen, compared to 33 %, 14 %, and 27 % of non-diabetic controls. Pancreatic lymph nodes were positive for EV protein in 60 % of T1D and aab+ cases. T1D and aab+ donors were more frequently VP1-positive in multiple organs than control donors (39 % vs. 11 %; including only insulin-positive donors). EV RNA was found in selected donors and from multiple tissue types except for duodenum, and individual T1D and aab+ donors were EV RNA-positive in multiple organs. The role of extra-pancreatic organs and their interplay with EV in T1D pathogenesis remains to be solved, but we hypothesize that these organs may serve as a reservoir for the virus which may reside in these tissues in a slow-replicating persistent form.

epidemiology↗