Novel Bacteroides Vulgatus strain protects against gluten-induced break of human celiac gut epithelial homeostasis: a pre-clinical proof-of-concept study.

BACKGROUND AND AIMS: We have identified a decreased abundance of microbial species known to have a potential anti-inflammatory, protective effect in subjects that developed Celiac Disease (CeD) compared to those who did not. We aim to confirm the potential protective role of one of these species, namely Bacteroides vulgatus, and to mechanistically establish the effect of bacterial bioproducts on gluten-dependent changes on human gut epithelial functions. METHODS: We identified, isolated, cultivated, and sequenced a unique novel strain (20220303-A2) of B. vulgatus found only in control subjects. Using a human gut organoid system developed from pre-celiac patients, we monitored epithelial phenotype and innate immune cytokines at baseline, after exposure to gliadin, or gliadin plus B. vulgatus cell free supernatant (CFS). RESULTS: Following gliadin exposure, we observed increases in epithelial cell death, epithelial monolayer permeability, and secretion of pro-inflammatory cytokines. These effects were mitigated upon exposure to B. vulgatus 20220303-A2 CFS, which had matched phenotype gene product mutations. These protective effects were mediated by epigenetic reprogramming of the organoids treated with B. vulgatus CFS. CONCLUSIONS: We identified a unique strain of B. vulgatus that may exert a beneficial role by protecting CeD epithelium against a gluten-induced break of epithelial tolerance through miRNA reprogramming. IMPACT: Gut dysbiosis precedes the onset of celiac disease in genetically at-risk infants. This dysbiosis is characterized by the loss of protective bacterial strains in those children who will go on to develop celiac disease. The paper reports the mechanism by which one of these protective strains, B. vulgatus, ameliorates the gluten-induced break of gut epithelial homeostasis by epigenetically re-programming the target intestinal epithelium involving pathways controlling permeability, immune response, and cell turnover.

Efficient SARS-CoV-2 infection antagonization by rhACE2 ectodomain multimerized onto the Avidin-Nucleic-Acid-NanoASsembly.

Nanodecoy systems based on analogues of viral cellular receptors assembled onto fluid lipid-based membranes of nano/extravescicles are potential new tools to complement classic therapeutic or preventive antiviral approaches. The need for lipid-based membranes for transmembrane receptor anchorage may pose technical challenges along industrial translation, calling for alternative geometries for receptor multimerization. Here we developed a semisynthetic self-assembling SARS-CoV-2 nanodecoy by multimerizing the biotin labelled virus cell receptor -ACE2- ectodomain onto a poly-avidin nanoparticle (NP) based on the Avidin-Nucleic-Acid-NanoASsembly-ANANAS. The ability of the assembly to prevent SARS-CoV-2 infection in human lung cells and the affinity of the ACE2:viral receptor-binding domain (RBD) interaction were measured at different ACE2:NP ratios. At ACE2:NP = 30, 90 % SARS-CoV-2 infection inhibition at ACE2 nanomolar concentration was registered on both Wuhan and Omicron variants, with ten-fold higher potency than the monomeric protein. Lower and higher ACE2 densities were less efficient suggesting that functional recognition between multi-ligand NPs and multi-receptor virus surfaces requires optimal geometrical relationships. In vivo studies in mice showed that the biodistribution and safety profiles of the nanodecoy are potentially suitable for preventing viral infection upon nasal instillation. Viral receptor multimerization using ANANAS is a convenient process which, in principle, could be rapidly adapted to counteract also other viral infections.

Vitamin D Levels in the Pre- and Post-COVID-19 Pandemic Periods and Related Confinement at Pediatric Age.

Coronavirus disease 2019 (COVID-19) restrictions have been correlated with vitamin D deficiency in children, but some uncertainties remain. We retrospectively studied vitamin 25-(OH) D blood levels in 2182 Italian children/adolescents hospitalized for various chronic diseases in the year before (n = 1052) and after (n = 1130) the nationwide lockdown. The type of underlying disease, gender, and mean age (91 ± 55 and 91 ± 61 months, respectively) of patients included in the two periods were comparable. Although mean levels were the same (p = 0.24), deficiency status affected a significantly higher number of subjects during the lockdown period than in the pre-COVID period (p = 0.03), particularly in summer (p = 0.02), and there was also a smoothing of seasonal variations in vitamin D levels. Particularly at risk were males (OR = 1.22; p = 0.03), the 1-5 year age group (OR = 1.57; p < 0.01) and the 6-12 year age group (OR = 1.30; p = 0.04). Infants appeared not to be affected (p = 1.00). In the post-COVID period, the risk of vitamin D deficiency was unchanged in disease-specific groups. However, the proportion of deficiency or severe deficiency differed significantly in the subgroup with endocrinopathy (higher; Chi-square p = 0.04), and with respiratory problems and obesity (lower; Chi-square p = 0.01 and p < 0.01, respectively). Conflicting/opposite literature results advocate for further studies to clearly indicate the need for supplementation during possible future periods of confinement.

Variations in Biodistribution and Acute Response of Differently Shaped Titania Nanoparticles in Healthy Rodents.

Titanium dioxide nanoparticles (TiO2 NPs) are one of the main sources of the nanoparticulate matter exposure to humans. Although several studies have demonstrated their potential toxic effects, the real nature of the correlation between NP properties and their interaction with biological targets is still far from being fully elucidated. Here, engineered TiO2 NPs with various geometries (bipyramids, plates, and rods) have been prepared, characterized and intravenously administered in healthy mice. Parameters such as biodistribution, accumulation, and toxicity have been assessed in the lungs and liver. Our data show that the organ accumulation of TiO2 NPs, measured by ICP-MS, is quite low, and this is only partially and transiently affected by the NP geometries. The long-lasting permanence is exclusively restricted to the lungs. Here, bipyramids and plates show a higher accumulation, and interestingly, rod-shaped NPs are the most toxic, leading to histopathological pulmonary alterations. In addition, they are also able to induce a transient increase in serum markers related to hepatocellular injury. These results indicate that rods, more than bipyramidal and spherical geometries, lead to a stronger and more severe biological effect. Overall, small physico-chemical differences can dramatically modify both accumulation and safety.

Early Antibody Dynamics in a Prospective Cohort of Children At Risk of Celiac Disease.

INTRODUCTION: The purpose of this study was to identify possible serum biomarkers predicting celiac disease (CD) onset in children at risk. METHODS: A subgroup from an ongoing, international prospective study of children at risk of CD was classified according to an early trajectory of deamidated gliadin peptides (DGPs) immunoglobulin (Ig) G and clinical outcomes (CD, potential CD, and CD autoimmunity). RESULTS: Thirty-eight of 325 children developed anti-tissue transglutaminase IgA antibody (anti-tTG IgA) seroconversion. Twenty-eight of 38 children (73.6%) showed an increase in anti-DGPs IgG before their first anti-tTG IgA seroconversion. DISCUSSION: Anti-DGPs IgG can represent an early preclinical biomarker predicting CD onset in children at risk.

Development of a Nanoparticle-Based Approach for the Blood-Brain Barrier Passage in a Murine Model of Amyotrophic Lateral Sclerosis.

The development of nanoparticles (NPs) to enable the passage of drugs across blood-brain barrier (BBB) represents one of the main challenges in neuropharmacology. In recent years, NPs that are able to transport drugs and interact with brain endothelial cells have been tested. Here, we investigated whether the functionalization of avidin-nucleic-acid-nanoassembly (ANANAS) with apolipoprotein E (ApoE) would allow BBB passage in the SOD1G93A mouse model of amyotrophic lateral sclerosis. Our results demonstrated that ANANAS was able to transiently cross BBB to reach the central nervous system (CNS), and ApoE did not enhance this property. Next, we investigated if ANANAS could improve CNS drug delivery. To this aim, the steroid dexamethasone was covalently linked to ANANAS through an acid-reversible hydrazone bond. Our data showed that the steroid levels in CNS tissues of SOD1G93A mice treated with nanoformulation were below the detection limit. This result demonstrates that the passage of BBB is not sufficient to guarantee the release of the cargo in CNS and that a different strategy for drug tethering should be devised. The present study furthermore highlights that NPs can be useful in improving the passage through biological barriers but may limit the interaction of the therapeutic compound with the specific target.

Diagnostic Value of Persistently Low Positive TGA-IgA Titers in Symptomatic Children With Suspected Celiac Disease.

OBJECTIVES: While the algorithm to diagnose celiac disease (CD) in children with elevated anti-transglutaminase IgA (TGA-IgA) titers (>10 times upper limit of normal, ULN) is well defined, the management of children with low TGA-IgA values represents a clinical challenge. We aimed to identify the diagnostic value of persistently low positive TGA-IgA titers in predicting CD in children. METHODS: We retrospectively analyzed children with symptoms or signs of CD, not eligible for a no-biopsy approach. We included children with at least 2 TGA-IgA measurements, endomysial antibody (EMA) assessment and esophagogastroduodenoscopy with biopsies. TGA-IgA values were provided as multiples of ULN. Patients were classified in groups according to median TGA-IgA values: A (TGA-IgA>1 ≤ 5 × ULN; defined as "low-positive"), B (TGA-IgA > 5 < 10 × ULN; "moderate-positive"), and C (controls). RESULTS: Data of 281 children were analyzed. Of 162 children in group A, CD was diagnosed in 142 (87.7%), whereas normal duodenal mucosa was found in 20. In group B, all 62 children (100%) received a CD diagnosis. Group C included 57 controls. EMA were undetectable in 31 (15%) of mucosal atrophy cases. On the receiver-operating characteristic curve (area under the curve = 0.910), a mean value of 1.7 ULN showed a sensitivity of 81.4% and specificity of 81.8% to predict mucosal damage. CONCLUSIONS: Repeated low or moderate TGA-IgA values (<5 ULN or <10 ULN) are good predictors of a CD diagnosis. Symptomatic children with persistently low positive TGA-IgA titers should undergo esophagogastroduodenoscopy regardless of their EMA status.

Association between Elevated TGA-IgA Titers and Older Age at Diagnosis with Absence of HBV Seroconversion in Celiac Children.

Patients with celiac disease can have a low rate of protective hepatitis B (HBV) antibody titers after vaccination. We aimed to evaluate the HBV seroconversion in celiac disease (CD) children at the time of diagnosis as well as to identify the presence of possible predictive factors. Celiac disease children were prospectively enrolled and tested for antibodies against the S protein of HBV (HBsAg) at time of diagnosis between January 2009 and February 2020. Based on the serologic response to the vaccine, "responders" and "non-responders" were identified. Statistical analysis has been performed through R statistical software (3.5.1 version, R core Team) Of 96 CD children evaluated, 41.7% (n = 40) showed non-protective or absent antibody titers against HBV. Elevated IgA-antibodies against transglutaminase 2 (TGA-IgA) values and older age at diagnosis were associated with an absent seroconversion to HBV vaccine, while presenting symptoms were not significant. An elevated prevalence of absent seroconversion to HBV vaccine exists in this cohort of CD patients at the time of disease diagnosis. Elevated TGA-IgA titers and older age at diagnosis seem to negatively predict seroconversion. Further studies are needed to identify the real profile of "non-responders", aiming to organize surveillance and eventual revaccination strategy.

Cellulose nanocrystals: a multimodal tool to enhance the targeted drug delivery against bone disorders.

Aim: We investigated the use of cellulose nanocrystals (CNCs) as drug nanocarriers combining an anti-osteoporotic agent, alendronate (ALN), and an anti-cancer drug, doxorubicin (DOX). Materials & methods: CNC physicochemical characterization, in vivo imaging coupled with histology and in vitro uptake and toxicity assays were carried out. Results:In vivo CNC-ALN did not modify bone tropism and lung penetration, whereas its liver and kidney accumulation was slightly higher compared with CNCs alone. In vitro studies showed that CNC-ALN did not impair ALN's effect on osteoclasts, whereas CNC-DOX confirmed the therapeutic potential against bone metastatic cancer cells. Conclusions: This study provides robust proof of the potential of CNCs as easy, flexible and specific carriers to deliver compounds to the bone.

A landfarming application technique used as environmental remediation for coal oil pollution.

Since the massive exploitation of the Val d'Agri (Basilicata-Italy) oilfield has started, a lot of environmental pollution accidents have occurred in the same region. This research takes as starting point the heavy accident occurred in the year 2000, when 15,150 kg of coal oil were spilt all over the Agri river bed and the surrounding fields. In that particular case, the environmental reclamation was achieved by the removal of the polluted soil and its dump-storage. This research work suggests an environmental restoration which is an alternative solution to what has been practiced before, and it is achieved by the so called bioremediation methods, particularly the "landfarming on site" technique.