Impaired immune responses have been hypothesised to be a possible trigger of unfavourable outcomes in coronavirus disease 2019 (COVID-19). We aimed to characterise IgM memory B cells in patients with ...COVID-19 admitted to an internal medicine ward in Northern Italy. Overall, 66 COVID-19 patients (mean age 74 ± 16.6 years; 29 females) were enrolled. Three patients (4.5%; 1 female) had been splenectomised and were excluded from further analyses. Fifty-five patients (87.3%) had IgM memory B cell depletion, and 18 (28.6%) died during hospitalisation (cumulative incidence rate 9.26/100 person-week; 5.8-14.7 95% CI). All patients who died had IgM memory B cell depletion. A superimposed infection was found in 6 patients (9.5%), all of them having IgM memory B cell depletion (cumulative incidence rate 3.08/100 person-week; 1.3-6.8 95% CI). At bivariable analyses, older age, sex, number of comorbidities, and peripheral blood lymphocyte count < 1500/µl were not correlated with IgM memory B cell depletion. A discrete-to-marked reduction of the B-cell compartment was also noticed in autoptic spleen specimens of two COVID-19 patients. We conclude that IgM memory B cells are commonly depleted in COVID-19 patients and this correlates with increased mortality and superimposed infections.
Special AT-rich sequence-binding protein 2 (SATB2) is a transcription factor expressed by colonic cryptic epithelium and epithelial neoplasms of the lower gastrointestinal (GI) tract, as well as by ...small bowel adenocarcinomas (SBAs), though at a lower rate. Nevertheless, up to now, only small SBA series, often including a very limited number of Crohn’s disease-associated SBAs (CrD-SBAs) and celiac disease-associated SBAs (CD-SBA), have been investigated for SATB2 expression. We evaluated the expression of SATB2 and other GI phenotypic markers (cytokeratin (CK) 7 and CK20, caudal type homeobox 2 (CDX2) and alpha-methylacyl-CoA racemase (AMACR)), as well as mismatch repair (MMR) proteins, in 100 SBAs, encompassing 34 CrD-SBAs, 28 CD-SBAs and 38 sporadic cases (Spo-SBAs). Any mutual association and correlation with other clinico-pathologic features, including patient prognosis, were searched. Twenty (20%) SATB2-positive SBAs (4 CrD-SBAs, 7 CD-SBAs and 9 Spo-SBAs) were identified. The prevalence of SATB2 positivity was lower in CrD-SBA (12%) in comparison with both CD-SBAs (25%) and Spo-SBAs (24%). Interestingly, six SBAs (two CD-SBAs and four Spo-SBAs) displayed a full colorectal carcinoma (CRC)-like immunoprofile (CK7−/CK20+/CDX2+/AMACR+/SATB2+); none of them was a CrD-SBA. No association between SATB2 expression and MMR status was observed. Although SATB2-positive SBA patients showed a more favorable outcome in comparison with SATB2-negative ones, the difference did not reach statistical significance. When cancers were stratified according to CK7/CK20 expression patterns, we found that CK7−/CK20- SBAs were enriched with MMR-deficient cases (71%) and patients with CK7−/CK20− or CK7−/CK20+ SBAs had a significantly better survival rate compared to those with CK7+/CK20− or CK7+/CK20+ cancers (p = 0.002). To conclude, we identified a small (6%) subset of SBAs featuring a full CRC-like immunoprofile, representing a potential diagnostic pitfall in attempts to identify the site of origin of neoplasms of unknown primary site. In contrast with data on colorectal carcinoma, SATB2 expression is not associated with MMR status in SBAs. CK patterns influence patient survival, as CK7−/CK20− cancers show better prognosis, a behavior possibly due to the high rate of MMR-deficient SBAs within this subgroup.
External fistulas represent a disabling manifestation of Crohn's disease with a difficult curability and a high relapse rate despite a large therapeutic armamentarium. Stem cell therapy is a novel ...and promising approach for treatment of chronic inflammatory conditions. We therefore investigated the feasibility, safety and efficacy of serial intrafistular injections of autologous bone marrow-derived mesenchymal stromal cells (MSCs) in the treatment of fistulising Crohn's disease.
We enrolled 12 consecutive outpatients (eight males, median age 32 years) refractory to or unsuitable for current available therapies. MSCs were isolated from bone marrow and expanded ex vivo to be used for both therapeutic and experimental purposes. Ten patients (two refused) received intrafistular MSC injections (median 4) scheduled every 4 weeks, and were monitored by surgical, MRI and endoscopic evaluation for 12 months afterwards. The feasibility of obtaining at least 50×10⁶ MSCs from each patient, the appearance of adverse events, and the efficacy in terms of fistula healing and reduction of both Crohn's disease and perianal disease activity indexes were evaluated. In addition, the percentage of both mucosal and circulating regulatory T cells expressing FoxP3, and the ability of MSCs to influence mucosal T cell apoptosis were investigated.
MSC expansion was successful in all cases; sustained complete closure (seven cases) or incomplete closure (three cases) of fistula tracks with a parallel reduction of Crohn's disease and perianal disease activity indexes (p < 0.01 for both), and rectal mucosal healing were induced by treatment without any adverse effects. The percentage of mucosal and circulating regulatory T cells significantly increased during the treatment and remained stable until the end of follow up (p < 0.0001 and p < 0.01, respectively). Furthermore, MSCs have been proven to affect mucosal T cell apoptotic rate.
Locally injected MSCs represent a feasible, safe and beneficial therapy in refractory fistulising Crohn's disease.
Abstract Background & aims Through inhibition of iron absorption and iron mobilization from tissue stores, hepcidin exerts a negative control on iron homeostasis. Hepcidin, in fact, promotes the ...degradation of ferroportin (Fpn1), the iron exporter molecule expressed on the membrane of hepatocytes and macrophages, thus preventing iron release from cells to plasma. Hepcidin effects on enterocytes, however, are less clear. Aim of the present study was to further investigate the regulation of iron absorption by hepcidin. Methods The transcriptional response of human duodenal mucosa to hepcidin was investigated using organ cultures of duodenal biopsies perendoscopically collected from healthy controls. Biopsies were cultured for 4 hours with or without hepcidin-25 and were then assayed for the expression of iron-related genes. Results In samples that had not been exposed to hepcidin, correlations were found between the expression of genes involved in iron absorption: DMT1 , Fpn1 , Dcytb and HCP1 . In ex vivo experiments hepcidin down-regulated mRNA levels of the iron transporters Fpn1, and DMT1 , of the ferric reductase Dcytb , of the ferroxidase hephaestin , and of the putative heme carrier protein HCP1. Conclusions Through the reported transcriptional changes hepcidin can modulate several steps of the iron absorption process, including the reduction of dietary iron by Dcytb, its uptake by enterocytes through DMT1, the mucosal uptake of heme iron by HCP1, and enterocyte iron release to plasma by Fpn1 in conjunction with hephaestin.
Anemia is a common extraintestinal manifestation of inflammatory bowel disease (IBD), with a 6% to 74% prevalence and a negative impact on patient survival and quality of life, although the ...prevalence is apparently declining due to improved disease treatment. We aimed to investigate the prevalence, pathogenesis, and clinical correlates of anemia in Italian patients with IBD.
A multicenter, prospective, observational study, involving 28 Italian gastroenterology centers, was conducted to investigate the epidemiology and consequences of IBD-associated anemia. Clinical and laboratory data of anemic patients were obtained at study enrolment.
Anemia was diagnosed in 737 of 5416 adult IBD outpatients (prevalence 13.6%); females were more commonly affected than males (odds ratio, 1.5; 95% confidence interval CI, 1.2-1.7) and had more severe anemia. In the majority of cases, anemia was due to iron deficiency (62.5% of cases; 95% CI, 58.3%-66.6%), either isolated or in association with inflammation and/or vitamin deficiencies; anemia of inflammation accounted for only 8.3% of cases. More severe anemia was associated with increasing fatigue and worse quality of life. Only 68.9% of anemic patients with iron deficiency (95% CI, 63.4%-73.8%) and 34.6% of those with vitamin deficiencies (95% CI, 26.2%-44.2%) were properly treated with supplementation therapy.
In Italy, the prevalence of IBD-associated anemia is lower than previously reported. Anemia of IBD is most commonly due to iron deficiency and contributes to fatigue and poor quality of life, but remains untreated in a large proportion of patients with iron and/or vitamin deficiencies. This study is registered at clinicaltrials.gov as NCT02872376.
Few conflicting data are currently available on the risk of SARS‐CoV‐2 infection in patients with autoimmune disorders. The studies performed so far are influenced, in most cases, by the treatment ...with immunosuppressive drugs, making it difficult to ascertain the burden of autoimmunity per se. For this reason, herein we assessed the susceptibility to COVID‐19 in immunosuppressive drug‐naïve patients with autoimmune diseases, such as autoimmune gastritis (AIG), celiac disease (CD), type 1 diabetes (T1D), and autoimmune thyroid disease (AITD). Telephone interviews were conducted on 400 patients—100 for each group—in May 2021 by looking at the positivity of molecular nasopharyngeal swabs and/or serology for SARS‐CoV‐2, the need for hospitalization, the outcome, and the vaccination status. Overall, a positive COVID‐19 test was reported in 33 patients (8.2%), comparable with that of the Lombardy general population (8.2%). In particular, seven patients with AIG, 9 with CD, 8 with T1D, and 9 with AITD experienced COVID‐19. Only three patients required hospitalization, none died, and 235 (58.7%) were vaccinated, 43 with AIG, 47 with CD, 91 with T1D, and 54 with AITD. These results seem to suggest that autoimmunity per se does not increase the susceptibility to COVID‐19. Also, COVID‐19 seems to be mild in these patients, as indicated by the low hospitalization rates and adverse outcomes, although further studies are needed to better clarify this issue.
The short isoform of thymic stromal lymphopoietin (TSLP), a cytokine constitutively expressed by epithelial cells, is crucial in preserving immune tolerance in the gut. TSLP deficiency has been ...implicated in sustaining intestinal damage in Crohn's disease. We explored mucosal TSLP expression and function in refractory and uncomplicated coeliac disease (CD), a T-cell-mediated enteropathy induced by gluten in genetically susceptible individuals.
TSLP isoforms-long and short-and receptors-TSLPR and interleukin (IL)-7Rα-were assessed by immunofluorescence, immunoblotting and qRT-PCR in the duodenum of untreated, treated, potential and refractory patients with CD. The ability of the serine protease furin or CD biopsy supernatants to cleave TSLP was evaluated by immunoblotting. The production of interferon (IFN)-γ and IL-8 by untreated CD biopsies cultured ex vivo with TSLP isoforms was also assessed.
Mucosal TSLP, but not TSLPR and IL-7Rα, was reduced in untreated CD and refractory CD in comparison to treated CD, potential CD and controls. Transcripts of both TSLP isoforms were decreased in active CD mucosa. Furin, which was overexpressed in active CD biopsies, was able to cleave TSLP in vitro. Accordingly, refractory and untreated CD supernatants showed higher TSLP-degrading capacity in comparison to treated CD and control supernatants. In our ex vivo model, both TSLP isoforms significantly downregulated IFN-γ and IL-8 production by untreated CD biopsies.
Reduced mucosal TSLP expression may contribute to intestinal damage in refractory and untreated CD. Further studies are needed to verify whether restoring TSLP might be therapeutically useful especially in refractory patients with CD.
•What is already known on this subject?•Glucagon-like peptide (GLP)-1 and -2 have been shown to regulate immune responses in immune-mediated disorders, such as Crohn’s disease (CD)•What are the new ...findings?•Basal GLP-1 levels were up-regulated in CD, while GLP-1 secretion was significantly reduced compared to healthy volunteers (HV) and patients with metabolic syndrome (MS)•Post-prandial GLP secretion was positively correlated to insulin secretion indices, both in CD and MS•How might it impact on clinical practice in the foreseeable future?•Future research should focus on metabolic alterations and GLP secretion in patients with CD, as these may represent therapeutic targets
Glucagon-like peptide GLP-1 and -2 have been shown to regulate immune responses in immune-mediated disorders, including Crohn’s disease (CD). Our aim was to investigate post-prandial GLP release and its potential link to chronic inflammation, insulin secretion/sensitivity and body composition changes in CD patients.
Fifteen patients with CD, 15 healthy controls (HC) and 15 patients with metabolic syndrome (MS) were recruited. All patients underwent assessment of body composition by means of bio-impedance followed by a meal tolerance test (MTT). Only one CD patient did not tolerate the MTT and was excluded.
Basal GLP-1 levels were up-regulated in CD, however, as compared to HC, stimulated GLP-1 secretion was significantly reduced in CD (-31 %, p < 0.05) as in MS (-52 %, p < 0.003). Similarly, basal GLP-2 levels were comparable to that of HC, while response to MTT in CD was virtually absent (p < 0.05). Similar fasting insulin sensitivity, estimated 1st and 2nd phase insulin secretion and insulinogenic index were found in CD and in HC. Post-prandial GLP secretion was positively correlated to insulin secretion indices, both in CD and MS. In CD, high-sensitive C reactive protein levels (hsCRP) and extra-cellular to intra-cellular water ratio (ECW/ICW), an index of cellular inflammation, were inversely correlated with stimulated GLP-1 (p < 0.05 and p < 0.01, respectively) levels.
CD is characterized by abnormal fasting and post-prandial GLP levels. Circulating GLP influences subclinical inflammation and glucose metabolism in CD patients, but not their body composition parameters.
Background:
CD4+Foxp3+ regulatory T cells (Treg) inhibit T‐cell proliferation in vitro and are effective in suppressing colitis in mouse models. Tumor necrosis factor (TNF)‐α, which is centrally ...involved in Crohn's disease (CD) pathogenesis, also impairs Treg function. Here we investigated the influence of anti‐TNF therapy on Treg frequency and function in CD.
Methods:
Twenty CD patients were treated with infliximab administered at weeks 0, 2, and 6. Blood was collected immediately before the first infusion and after 10 weeks. Treg frequency was quantified by flow cytometry. Treg function was measured using a standard coculture assay. Serum levels of transforming growth factor (TGF)‐β1 and interleukin (IL)‐10 were measured by enzyme‐linked immunosorbent assay (ELISA).
Results:
Pretreatment Treg frequency and serum TGF‐β1 levels were significantly higher in nonresponder than responder patients. Clinical improvement in 12 CD patients was associated with a significant increase of Treg frequency after 10 weeks. Treg were functionally active before and after treatment with infliximab, both in responder and nonresponder CD patients. In responder patients the restoration of Treg pool was accompanied by a parallel significant increase of serum TGF‐β1 and IL‐10. No significant change in the elevated Treg or serum TGF‐β1 was seen in nonresponder patients.
Conclusions:
This study suggests that there may be a relationship between numbers of Treg in the blood, serum TGF‐β1, and response to infliximab; however, further prospective studies are needed. (Inflamm Bowel Dis 2010)
Abstract 2676
Poster Board II-652
Crohn's disease (CD) is a disabling, chronic, relapsing inflammatory enteropathy caused by dysregulation of the immune tolerance towards intestinal bacteria in ...genetically susceptible individuals. Fistulas are an invalidating, often difficult to treat, complication of patients with CD. Mesenchymal stromal cells (MSCs) have been proved to be endowed with relevant immunomodulatory properties and represent a promising tool in therapeutic approaches of regenerative medicine, as well as in the treatment of immune-mediated diseases. We investigated the feasibility, safety and efficacy of local injection of autologous bone marrow (BM)-derived MSCs in the treatment of refractory CD fistulas.
MSCs were isolated and expanded ex vivo from BM of 12 patients (7 males, median age 33 years, range 16-59) and used for both experimental and therapeutic purposes. To increase biological safety of the cellular products, MSC ex vivo expansion was carried out in the presence of platelet lysate as substitute for foetal calf serum. All participants had an active disease (CD Activity Index, CDAI > 150; Perianal Disease Activity Index, PDAI > 8) at time of enrolment and had been unresponsive to previous medical and biological treatment and/or were unsuccessfully treated by surgery. The study was approved by the local Ethical Committee, and each patient gave written informed consent before entering the study. They received intrafistular injection of MSCs scheduled every 4 weeks (median 4 infusions) and were monitored at time of each injection, and 1, 3, 6, 12 months after the last treatment through clinical, serological, imaging and endoscopic (at 12 months only) investigations. The cytokine profile of MSCs and their ability to influence apoptosis of mucosal T cells obtained from involved and uninvolved colonic areas, were also analyzed.
MSC expansion was successful in all patients and no adverse event was recorded during and up to 12 months after treatment. Intrafistular injection of MSCs proved to be effective in inducing sustained closure of fistulas, with the appearance of regenerative tissue along the tracks. In particular, 7 patients (70%) benefited from complete and sustained healing of fistula tracks, while three had partial response, as demonstrated by rectosigmoidoscopic examination, endoscopy and magnetic resonance imaging. In particular, the use of contrast medium revealed the presence of regenerative tissue along the tracks and the absence of fibrotic tissue. All patients showed a significant reduction of both CDAI (pre-treatment and post-treatment median values being 294 SD 49 and 99 SD 32 at 6 months after the last infusion; p < 0.001) and PDAI (pre-treatment and post-treatment median values being 13.0 SD 2.2 and 4.5 SD 2.4 at 6 months after the last infusion; p< 0.001) reaching disease remission usually after the second procedure. The immunephenotype of circulating T lymphocytes, evaluated at time of each procedure and during follow-up, showed a progressive increase of the number of T cells expressing a regulatory phenotype, i.e. CD4+CD25bright FoxP3+ cells, which became significant (p<0.01) after the second procedure and remained stable up to 6 months after the last infusion. No modification of serum cytokines was observed at any time point. MSCs caused a sort of block of the rates of both apoptotic and living cells when incubated with T lymphocytes from diseased mucosa, whilst critically increased the apoptotic rate when incubated with T lymphocytes from apparently healthy mucosa. MSCs from CD patients displayed a cytokine pattern similar to that of MSCs from healthy donors.
Local injection of autologous BM-derived MSCs appeared feasible, safe and successful in treating fistulas associated with CD, thus indicating that the possibility to cure perianal CD does not seem a distant horizon.
No relevant conflicts of interest to declare.
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