Role of extracellular microvesicles in celiac disease as potential pathogenetic agents and biomarkers of intestinal inflammation

BACKGROUND AND AIM: Celiac Disease (CD) is a chronic intestinal disease caused by the ingestion of gluten. Microvesicles (MVs) belong to a heterogeneous population, released by cells both in homeostasis and pathological conditions. MVs can be considered mediators of inflammation and potential biomarkers. The aim of this study is: 1) to evaluate the possible role of MVs in the propagation of inflammation in CD, using MVs purified by supernatant of duodenal biopsies from CD patients; 2) to identify potential biomarkers by proteomic analysis of pasma-derived MVs from CD patients. MATERIAL AND METHODS: MVs were isolated by molecular exclusion chromatography and ultracentrifugation respectively from plasma and culture supernatant of duodenal biopsies of 10 active CD, 5 remission CD and 6 controls. Proteomic analysis of plasma-derived MVs was performed by mass spectrometry. The possible effects of duodenal-derived MVs on confluent Caco-2 cells were evaluated by measuring Transepithelial Electrical Resistance (TEER) and analyzing the expression of actin, tissue transglutaminase (TG2) and Zonula Occludens-1 (ZO-1). The dosage of IL-8 in the Caco-2 culture supernatant was carried out by ELISA test. The statistical analysis of the data obtained was performed using the Student's t-test. RESULTS: The proteomic analysis of circulating MVs showed 8 proteins from desmosome and cytoskeleton (desmoglein-1 and gamma-enteric actin) associated with the active phase of the disease. Caco-2 cells, treated with the MVs purified from the duodenal biopsies of active CD patients showed: 1) rearrangement of actin filaments; 2) increased expression of TG2; 3) decreased expression of the ZO-1 protein, although an alteration of intestinal permeability was not observed. The analysis of Caco-2 cell supernatants showed a statistically significant increase in IL-8 (p <0.05), in the presence of MVs isolated from biopsies of active CD patients, compared to remission CD patients and controls. CONCLUSIONS: MVs isolated from plasma of active CD patients could represent potential diagnostic and prognostic biomarkers. Although they don’t induce changes in intestinal permeability, MVs could contribute to inflammatory cascade increasing IL-8 production

Development of hybrid immunity during a period of high incidence of Omicron infections.

Seroprevalence and the proportion of people with neutralizing activity (functional immunity) against SARS-CoV-2 variants were high in early 2022. In this prospective, population- based, multi-region cohort study, we assessed the development of functional and hybrid immunity (induced by vaccination and infection) in the general population during this period of high incidence of infections with Omicron variants. We randomly selected and assessed individuals aged ≥16 years from the general population in southern (n = 739) and north-eastern (n = 964) Switzerland in March 2022. We assessed them again in June/July 2022, supplemented with a random sample from western (n = 850) Switzerland. We measured SARS-CoV-2 specific IgG antibodies and SARS-CoV-2 neutralizing antibodies against three variants (ancestral strain, Delta, Omicron). Seroprevalence remained stable from March 2022 (97.6%, n = 1894) to June/July 2022 (98.4%, n = 2553). In June/July, the percentage of individuals with neutralizing capacity against ancestral strain was 94.2%, against Delta 90.8% and against Omicron 84.9%, and 50.6% developed hybrid immunity. Individuals with hybrid immunity had highest median levels of anti-spike IgG antibodies titres [4518 World Health Organization units per millilitre (WHO U/mL)] compared with those with only vaccine- (4304 WHO U/mL) or infection- (269 WHO U/mL) induced immunity, and highest neutralization capacity against ancestral strain (hybrid: 99.8%, vaccinated: 98%, infected: 47.5%), Delta (hybrid: 99%, vaccinated: 92.2%, infected: 38.7%) and Omicron (hybrid: 96.4%, vaccinated: 79.5%, infected: 47.5%). This first study on functional and hybrid immunity in the Swiss general population after Omicron waves showed that SARS-CoV-2 has become endemic. The high levels of antibodies and neutralization support the emerging recommendations of some countries where booster vaccinations are still strongly recommended for vulnerable persons but less so for the general population

Factors associated with COVID-19 non-vaccination in Switzerland: a nationwide study

Objectives: We compared socio-demographic characteristics, health-related variables, vaccination-related beliefs and attitudes, vaccination acceptance, and personality traits of individuals who vaccinated against COVID-19 and who did not vaccinate by December 2021. Methods: This cross-sectional study used data of 10,642 adult participants from the Corona Immunitas eCohort, an age-stratified random sample of the population of several cantons in Switzerland. We used multivariable logistic regression models to explore associations of vaccination status with socio-demographic, health, and behavioral factors. Results: Non-vaccinated individuals represented 12.4% of the sample. Compared to vaccinated individuals, non-vaccinated individuals were more likely to be younger, healthier, employed, have lower income, not worried about their health, have previously tested positive for SARS-CoV-2 infection, express lower vaccination acceptance, and/or report higher conscientiousness. Among non-vaccinated individuals, 19.9% and 21.3% had low confidence in the safety and effectiveness of SARS-CoV-2 vaccine, respectively. However, 29.1% and 26.7% of individuals with concerns about vaccine effectiveness and side effects at baseline, respectively vaccinated during the study period. Conclusion: In addition to known socio-demographic and health-related factors, non-vaccination was associated with concerns regarding vaccine safety and effectiveness

Laparoscopic right hemicolectomy: a SICE (Società Italiana di Chirurgia Endoscopica e Nuove tecnologie) network prospective study on the approach to right colon lymphadenectomy in Italy: is there a standard?—CoDIG 2 (ColonDx Italian Group)

Background: Colon cancer is a disease with a worldwide spread. Surgery is the best option for the treatment of advanced colon cancer, but some aspects are still debated, such as the extent of lymphadenectomy. In Japanese guidelines, the gold standard was D3 dissection to remove the central lymph nodes (203, 213, and 223), but in 2009, Hoenberger et al. introduced the concept of complete mesocolic excision, in which surgical dissection follows the embryological planes to remove the mesentery entirely to prevent leakage of cancer cells and collect more lymph nodes. Our study describes how lymphadenectomy is currently performed in major Italian centers with an unclear indication on the type of lymphadenectomy that should be performed during right hemicolectomy (RH). Methods: CoDIG 2 is an observational multicenter national study that involves 76 Italian general surgery wards highly specialized in colorectal surgery. Each center was asked not to modify their usual surgical and clinical practices. The aim of the study was to assess the preference of Italian surgeons on the type of lymphadenectomy to perform during RH and the rise of any new trends or modifications in habits compared to the findings of the CoDIG 1 study conducted 4 years ago. Results: A total of 788 patients were enrolled. The most commonly used surgical technique was laparoscopic (82.1%) with intracorporeal (73.4%), side-to-side (98.7%), or isoperistaltic (96.0%) anastomosis. The lymph nodes at the origin of the vessels were harvested in an inferior number of cases (203, 213, and 223: 42.4%, 31.1%, and 20.3%, respectively). A comparison between CoDIG 1 and CoDIG 2 showed a stable trend in surgical techniques and complications, with an increase in the robotic approach (7.7% vs. 12.3%). Conclusions: This analysis shows how lymphadenectomy is performed in Italy to achieve oncological outcomes in RH, although the technique to achieve a higher lymph node count has not yet been standardized. Trial registration (ClinicalTrials.gov) ID: NCT05943951

Exogenous HIV-1 Nef Upsets the IFN-γ-Induced Impairment of Human Intestinal Epithelial Integrity

The mucosal tissues play a central role in the transmission of HIV-1 infection as well as in the pathogenesis of AIDS. Despite several clinical studies reported intestinal dysfunction during HIV infection, the mechanisms underlying HIV-induced impairments of mucosal epithelial barrier are still unclear. It has been postulated that HIV-1 alters enterocytic function and HIV-1 proteins have been detected in several cell types of the intestinal mucosa. In the present study, we analyzed the effect of the accessory HIV-1 Nef protein on human epithelial cell line.We used unstimulated or IFN-γ-stimulated Caco-2 cells, as a model for homeostatic and inflamed gastrointestinal tracts, respectively. We investigated the effect of exogenous recombinant Nef on monolayer integrity analyzing its uptake, transepithelial electrical resistance, permeability to FITC-dextran and the expression of tight junction proteins. Moreover, we measured the induction of proinflammatory mediators. Exogenous Nef was taken up by Caco-2 cells, increased intestinal epithelial permeability and upset the IFN-γ-induced reduction of transepithelial resistance, interfering with tight junction protein expression. Moreover, Nef inhibited IFN-γ-induced apoptosis and up-regulated TNF-α, IL-6 and MIP-3α production by Caco-2 cells while down-regulated IL-10 production. The simultaneous exposure of Caco-2 cells to Nef and IFN-γ did not affect cytokine secretion respect to untreated cells. Finally, we found that Nef counteracted the IFN-γ induced arachidonic acid cascade.Our findings suggest that exogenous Nef, perturbing the IFN-γ-induced impairment of intestinal epithelial cells, could prolong cell survival, thus allowing for accumulation of viral particles. Our results may improve the understanding of AIDS pathogenesis, supporting the discovery of new therapeutic interventions

Low risk of colon cancer in patients with celiac disease

Objective. Celiac disease (CD) has strongly been established as associated with some site-specific gastrointestinal malignancies. On the contrary, according to the few reports available, the risk of colon carcinoma in CD patients has been described similar to that of general population. In this cohort study, we describe the risk of colon carcinoma in a group of Italian celiac patients. Materials and methods. The study population included all CD patients diagnosed at the Collaborating Centers of the Italian Registry of CD between 1st January 1982 and 31st December 2006. Upon diagnosis of CD and upon at every subsequent clinical control, the Collaborating Centers filled in a validated form for each CD patient reporting information about demographic data, possible occurrence of a neoplasm and adherence to a gluten-free diet. Results. Out of 1757 celiac patients enrolled, 6 developed a colon carcinoma during the follow-up period (mean: 18.1 years). The standardized incidence ratio (SIR) resulted 0.29 (95% CI = 0.07-0.45). Stratifying the risk for the dietary gluten intake, the SIR dropped to 0.07 (95% CI = 0.009-0.27) for CD patients with a strict adherence to a gluten-free diet. Conclusion. We confirm the previous finding that there is low risk to develop a colon cancer in celiac patients. © 2014 Informa Healthcare