A New Butyrate Releaser Exerts a Protective Action against SARS-CoV-2 Infection in Human Intestine.

Butyrate is a major gut microbiome metabolite that regulates several defense mechanisms against infectious diseases. Alterations in the gut microbiome, leading to reduced butyrate production, have been reported in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A new butyrate releaser, useful for all the known applications of butyrate, presenting physiochemical characteristics suitable for easy oral administration, (N-(1-carbamoyl-2-phenyl-ethyl) butyramide (FBA), has been recently developed. We investigated the protective action of FBA against SARS-CoV-2 infection in the human small intestine and enterocytes. Relevant aspects of SARS-CoV-2 infection were assessed: infectivity, host functional receptor angiotensin-converting enzyme-2 (ACE2), transmembrane protease serine 2 (TMPRSS2), neuropilin-1 (NRP1), pro-inflammatory cytokines expression, genes involved in the antiviral response and the activation of Nf-kB nuclear factor (erythroid-derived 2-like) 2 (Nfr2) pathways. We found that FBA positively modulates the crucial aspects of the infection in small intestinal biopsies and human enterocytes, reducing the expression of ACE2, TMPRSS2 and NRP1, pro-inflammatory cytokines interleukin (IL)-15, monocyte chemoattractant protein-1 (MCP-1) and TNF-α, and regulating several genes involved in antiviral pathways. FBA was also able to reduce the number of SARS-CoV-2-infected cells, and ACE2, TMPRSS2 and NRP1 expression. Lastly, through the inhibition of Nf-kB and the up-regulation of Nfr2, it was also able to reduce the expression of pro-inflammatory cytokines IL-15, MCP-1 and TNF-α in human enterocytes. The new butyrate releaser, FBA, exerts a preventive action against SARS-CoV-2 infection. It could be considered as an innovative strategy to limit COVID-19.

The Effect of Gluten-free Diet on Clinical Symptoms and the Intestinal Mucosa of Patients With Potential Celiac Disease.

In this prospective study, we evaluated the effect of gluten-free diet (GFD) in a cohort of 65 children with potential celiac disease. Patients received GFD for signs/symptoms (N = 47) or parents' choice (N = 18). Most frequent signs/symptoms were low body mass index (36%), recurrent abdominal pain (34%), and diarrhea (19%). Of the 35/47 patients followed-up on GFD, only 54% (19/35) showed a complete clinical response. In 9 of 65 patients an intestinal biopsy was also performed after at least 1 year of GFD. No significant differences were observed in terms of Marsh grade (P = 0.33), lamina propria CD25+ cells (P = 0.80), CD3+ (P = 0.9), and γδ+ (P = 0.59) intraepithelial lymphocytes density and intestinal anti-TG2 deposits (P = 0.60). In conclusion, caution is necessary before attributing all symptoms to gluten in this condition.

Distinct and Synergistic Contributions of Epithelial Stress and Adaptive Immunity to Functions of Intraepithelial Killer Cells and Active Celiac Disease.

BACKGROUND & AIMS: The mechanisms of tissue destruction during progression of celiac disease are poorly defined. It is not clear how tissue stress and adaptive immunity contribute to the activation of intraepithelial cytotoxic T cells and the development of villous atrophy. We analyzed epithelial cells and intraepithelial cytotoxic T cells in family members of patients with celiac disease, who were without any signs of adaptive antigluten immunity, and in potential celiac disease patients, who have antibodies against tissue transglutaminase 2 in the absence of villous atrophy. METHODS: We collected blood and intestinal biopsy specimens from 268 patients at tertiary medical centers in the United States and Italy from 2004 to 2012. All subjects had normal small intestinal histology. Study groups included healthy individuals with no family history of celiac disease or antibodies against tissue transglutaminase 2 (controls), healthy family members of patients with celiac disease, and potential celiac disease patients. Intraepithelial cytotoxic T cells were isolated and levels of inhibitory and activating natural killer (NK) cells were measured by flow cytometry. Levels of heat shock protein (HSP) and interleukin 15 were measured by immunohistochemistry, and ultrastructural alterations in intestinal epithelial cells (IECs) were assessed by electron microscopy. RESULTS: IECs from subjects with a family history of celiac disease, but not from subjects who already had immunity to gluten, expressed higher levels of HS27, HSP70, and interleukin-15 than controls; their IECs also had ultrastructural alterations. Intraepithelial cytotoxic T cells from relatives of patients with celiac disease expressed higher levels of activating NK receptors than cells from controls, although at lower levels than patients with active celiac disease, and without loss of inhibitory receptors for NK cells. Intraepithelial cytotoxic T cells from potential celiac disease patients failed to up-regulate activating NK receptors. CONCLUSIONS: A significant subset of healthy family members of patients with celiac disease with normal intestinal architecture had epithelial alterations, detectable by immunohistochemistry and electron microscopy. The adaptive immune response to gluten appears to act in synergy with epithelial stress to allow intraepithelial cytotoxic T cells to kill epithelial cells and induce villous atrophy in patients with active celiac disease.

Safety for patients with celiac disease of baked goods made of wheat flour hydrolyzed during food processing.

BACKGROUND & AIMS: Celiac disease (CD) is characterized by an inflammatory response to wheat gluten, rye, and barley proteins. Fermentation of wheat flour with sourdough lactobacilli and fungal proteases decreases the concentration of gluten. We evaluated the safety of daily administration of baked goods made from this hydrolyzed form of wheat flour to patients with CD. METHODS: Patients were randomly assigned to consumption of 200 g per day of natural flour baked goods (NFBG) (80,127 ppm gluten; n = 6), extensively hydrolyzed flour baked goods (S1BG) (2480 ppm residual gluten; n = 2), or fully hydrolyzed baked goods (S2BG) (8 ppm residual gluten; n = 5) for 60 days. RESULTS: Two of the 6 patients who consumed NFBG discontinued the challenge because of symptoms; all had increased levels of anti-tissue transglutaminase (tTG) antibodies and small bowel deterioration. The 2 patients who ate the S1BG goods had no clinical complaints but developed subtotal atrophy. The 5 patients who ate the S2BG had no clinical complaints; their levels of anti-tTG antibodies did not increase, and their Marsh grades of small intestinal mucosa did not change. CONCLUSIONS: A 60-day diet of baked goods made from hydrolyzed wheat flour, manufactured with sourdough lactobacilli and fungal proteases, was not toxic to patients with CD. A combined analysis of serologic, morphometric, and immunohistochemical parameters is the most accurate method to assess new therapies for this disorder.

Immunoglobulin A anti-tissue transglutaminase antibody deposits in the small intestinal mucosa of children with no villous atrophy.

OBJECTIVES: Anti-tissue transglutaminase (anti-TG2) immunoglobulin A (IgA) autoantibodies are detectable in the serum of most patients with untreated celiac disease (CD). Their deposits in the intestine of patients with CD with severe enteropathy are considered specific for this condition. The histological spectrum of CD includes cases with normal villous architecture. The aim of this study was to look for anti-TG2 IgA deposits in the intestine of children with normal villous architecture and to relate them with other markers of gluten sensitivity. PATIENTS AND METHODS: A total of 57 children with normal duodenal villous architecture and markers of gluten sensitivity were considered. Of those, 39 showed positive serum anti-endomysium antibodies and/or high levels of anti-TG2 antibodies (group 1), and 18 were seronegative with only a greater density of gammadelta intraepithelial lymphocytes (group 2). Thirty-four children with no markers of gluten sensitivity and a normal mucosa represented the control group (group 3). The duodenal sections of all patients were investigated for deposited anti-TG2 IgA by double immunofluorescence. Human lymphocyte antigen molecular typing was performed. RESULTS: In group 1 and in group 2, 33 of 39 children (85%) and 12 of 18 children (66%) showed subepithelial anti-TG2 IgA intestinal deposits, respectively. Only in 3 of 34 (8.8%) children with no markers of gluten sensitivity were anti-TG2 IgA deposits noted. CONCLUSIONS: A subgroup of children with no serum CD-associated autoantibodies, but greater density of gammadelta intraepithelial lymphocytes, shows a clear anti-TG2 IgA deposition in the duodenal mucosa. These children must be investigated further for possible gluten sensitivity.

Humoral immune response to tissue transglutaminase is related to epithelial cell proliferation in celiac disease.

BACKGROUND & AIMS: Tissue transglutaminase (tTG) autoantibodies are markers of celiac disease, and the enzyme is required for several crucial biological processes. The aim of this study was to determine whether these autoantibodies are involved in the pathogenesis of the mucosal lesion typical of celiac disease. METHODS: Using rhodamine-conjugated phalloidin staining, we evaluated whether tTG antibodies, both commercially available and cloned from patients with celiac disease, cause cytoskeletal changes in Caco-2, MCF7, and NIH 3T3 cells. We monitored cell levels of bromodeoxyuridine incorporation to determine whether tTG autoantibodies are able to induce NIH 3T3 fibroblasts and epithelial mucosal cells into S phase. RESULTS: Treatment with tTG antibodies caused a dose-dependent increase of membrane ruffling in Caco-2, MCF7, and NIH 3T3 cells. It also dose-dependently induced G(0)-synchronized NIH 3T3 fibroblasts into S phase but did not affect the rate of apoptosis. Similarly, tTG antibodies induced S-phase entry of epithelial cells in cultured intestinal biopsy specimens from patients with celiac disease. They did not affect biopsy specimens from patients without celiac disease. CONCLUSIONS: Our results suggest that tTG autoantibodies per se, by interacting with the extracellular membrane-bound transglutaminase, may play an important role in epithelial cell proliferation in celiac disease.

Growth factor-like activity of gliadin, an alimentary protein: implications for coeliac disease.

BACKGROUND: Gliadins, a family of wheat proteins, are central to the pathogenesis of celiac disease (CD). In addition to 'immunogenic' effects, gliadin directly affects cultured cells and intestine preparations, and produces damage in vivo, via a separate 'toxic' peptide, such as A-gliadin p31-43 (P31-43). AIMS: Understanding the molecular mechanisms underlying direct non T-cell mediated effects of gliadin peptides, and assessing their potential role in promoting CD. METHOD: Gliadin effects were tested on a number of cell lines and on cultured mucosa samples by evaluating cytoskeleton rearrangements, endocytosis, proliferation and apoptosis. Standard biochemical methods were used to assess prolonged epidermal growth factor receptor (EGFR) activation. RESULTS: Crude gliadin peptic-tryptic peptides (PTG], or P31-43 alone, fully reproduce the effects of epidermal growth factor (EGF] on actin cytosketon, cell cycle and cell proliferation of various cell lines. Inhibitor studies demonstrate the role of EGFR in the early response to gliadin exposure, pointing to activation of the EGFR pathway. Peptide P31-43 is not similar to any EGFR ligand, but can delay inactivation of the EGFR interfering with its endocytosis. Gliadin-induced delay of EGFR endocytosis in cultured intestinal biopsies, together with S-phase entry of epithelial intestinal cells, confirm a role for EGFR activation in CD. CONCLUSION: The ability of gliadin peptides to delay EGFR inactivation through interference with the endocytic pathway suggests a model where gliadin fragments amplify the effects of trace amounts of EGF, and possibly of other growth factors, by prolonging receptor activation. The results, using cultures of coeliac intestinal biopsies, highlight the role of the EGF pathway in establishing and maintaining the typical atrophic and proliferative alterations of the small intestine in CD.

Clinical, HLA, and small bowel immunohistochemical features of children with positive serum antiendomysium antibodies and architecturally normal small intestinal mucosa.

BACKGROUND: Antiendomysium antibodies have a high sensitivity and specificity for celiac disease. A small percentage of subjects positive for these antibodies have a small intestinal mucosa hitherto considered normal. OBJECTIVES: The aim of this study was to characterize the clinical, serological, immunogenetic, and immunohistological features of these subjects. METHODS: From 409 patients who were positive for celiac-related antibodies, we selected 24 (5.9%) patients who had an architecturally normal small intestinal mucosa. One hundred age-matched celiac patients with a "flat" small intestinal mucosa, and 50 age-matched nonceliac children were also studied. The number of CD3+ and gammadelta+ intraepithelial lymphocytes and of CD25+ lamina propria mononuclear cells, and the expression of crypt HLA-DR and lamina propria ICAM-1 were assessed. HLA haplotyping was also performed. RESULTS: Eleven (45.8%) of the 24 patients had a distinct infiltrative pattern, i.e., an increase in CD3+ intraepithelial lymphocytes (> 2SD of the nonceliac group), whereas 17 (70.8%) had a higher density of intraepithelial gammadelta+ cells. In 17 (70.8%) patients, the number of lamina propria CD25+ cells was increased and/or the expression of ICAM-1 and crypt HLA-DR was enhanced. All 24 patients carried the celiac disease-associated HLA haplotypes. Two of the six patients who remained on a normal diet and underwent a second jejunal biopsy developed villous atrophy. CONCLUSIONS: Most of the patients with serum antiendomysium antibodies and normal jejunal histology showed immunohistochemical signs of immune activation in the epithelium, lamina propria, and crypts. We recommend that such patients be monitored to assess their progress and to determine whether they need a gluten-free diet.

[An observational study of effectiveness in community residential facilities]. / L'efficacia nella pratica delle strutture residenziali territoriali: uno studio osservazionale.

AIMS: Evaluation of community residential facilities effectiveness in the Department of Mental Health of Desio (Milan). METHOD: Outcomes in symptoms, disability, family burden and quality of life were evaluated during one year through a longitudinal study, using a pre-test and post test design without control group. RESULTS: Residential care is effective in reducing disability and symptoms, while it is not effective towards family burden. Quality of life is improved in some domains, but not in others (e.g. social and family relationships). CONCLUSIONS: Outcome assessment is feasible in residential facilities, following a multiaxial and multifactorial model. We need to clarify the goals of residential care, focussing on active components of the residential treatment.

In vitro-deranged intestinal immune response to gliadin in type 1 diabetes.

Dietary gluten has been associated with an increased risk of type 1 diabetes. We have evaluated inflammation and the mucosal immune response to gliadin in the jejunum of patients with type 1 diabetes. Small intestinal biopsies from 17 children with type 1 diabetes without serological markers of celiac disease and from 50 age-matched control subjects were examined by immunohistochemistry. In addition, biopsies from 12 type 1 diabetic patients and 8 control subjects were cultured with gliadin or ovalbumin peptic-tryptic digest and examined for epithelial infiltration and lamina propria T-cell activation. The density of intraepithelial CD3(+) and gammadelta(+) cells and of lamina propria CD25(+) mononuclear cells was higher in jejunal biopsies from type 1 diabetic patients versus control subjects. In the patients' biopsies cultured with peptic-tryptic gliadin, there was epithelial infiltration by CD3(+) cells, a significant increase in lamina propria CD25(+) and CD80(+) cells and enhanced expression of lamina propria CD54 and crypt HLA-DR. No such phenomena were observed in control subjects, even those with celiac disease-associated HLA haplotypes. In conclusion, signs of mucosal inflammation were present in jejunal biopsies from type 1 diabetic patients, and organ culture studies indicate a deranged mucosal immune response to gliadin.

Markers of potential coeliac disease in patients with Hashimoto's thyroiditis.

OBJECTIVE: Coeliac disease (CD) is associated with autoimmune thyroid disease. Gluten sensitivity represents a spectrum, with at one end cases with severe gluten-dependent enteropathy, and at the other subjects with minor signs of deranged mucosal immune response. The aim of this paper was to look for signs of minor small bowel injury and immunohistochemical markers of gluten sensitivity in a group of patients with Hashimoto's disease. SUBJECTS AND METHODS: Fourteen patients with Hashimoto's thyroiditis without serological evidence of CD underwent immunohistochemical analysis of jejunal biopsies. RESULTS: In 6/14 cases (43%) an increased density of gammadelta T cell receptor bearing intra-epithelial lymphocytes was found. In 6/14 (43%) signs of mucosal T cell activation (presence of interleukin 2 (IL2) receptor (CD25) on lamina propria T cells and/or expression of human lymphocyte antigen (HLA)-DR molecules on crypt epithelial cells) were noted. In 4 out of 6 such cases, HLA haplotypes were described in association with CD. CONCLUSION: A significant proportion of patients with Hashimoto's thyroiditis present signs of 'potential' CD and of activated mucosal T cell immunity. The gluten dependence of such findings remains to be ascertained.