Lack of Seroconversion Following COVID-19 Vaccination Is an Independent Risk Factor for SARS-CoV-2 Infection in Patients With Inflammatory Bowel Disease: Data from ESCAPE-IBD, an IG-IBD Study

This prospective study reported 2 key results: (1) lack of seroconversion following 2 doses of COVID-19 vaccines is an independent predictor of SARS-CoV-2 infection; (2) treatments for IBD were not associated with increased risk of SARS-CoV-2 infection.

Safety, hesitancy of coronavirus disease 2019 vaccination and pandemic burden in patients with inflammatory bowel disease: data of a national study (ESCAPE-IBD)

BACKGROUND AND AIMS

The purpose of this study was to present data on the safety of anti- severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in a cohort of inflammatory bowel disease (IBD) patients of an ongoing multicenter study (ESCAPE-IBD) sponsored by the Italian Group for the study of Inflammatory Bowel Disease (ClinicalTrials.gov Identifier: NCT04769258).

METHODS

Anti-SARS-CoV-2 vaccination was administrated to 809 IBD patients. Interviews were conducted to report adverse events related to vaccination. Of these 809, 346 patients were surveyed on the pandemic burden and the main reason for hesitancy in coronavirus disease 2019 vaccination. The chi-square test was used to compare categorical variables. Logistic regression was used to assess the relationship between disease-related characteristics and the onset of adverse events.

RESULTS

About 45% of patients had at least one side effect, following the first dose (10%), the second (15%), and both doses (19%). All the adverse events were mild and lasted only a few days. Logistic regression analysis revealed that female sex ( P  < 0.001), younger age ( P  = 0.001), seroconversion ( P  = 0.002), and comorbidity ( P  < 0.001) were significantly associated with adverse events. The survey showed that the main concerns were the possibility of adverse event (33%). Almost all patients (99%) felt safer having been vaccinated at their IBD reference center.

CONCLUSION

The vaccine reactions experienced in IBD patients were mostly self-limited. We found high acceptance and good safety of SARS-CoV-2 vaccination in our cohort.

Reduced humoral response to two doses of COVID-19 vaccine in patients with inflammatory bowel disease: Data from ESCAPE-IBD, an IG-IBD study

BACKGROUND

Patients on immunosuppressive drugs have been excluded from COVID-19 vaccines trials, creating concerns regarding their efficacy.

AIMS

To explore the humoral response to COVID-19 vaccines in patients with inflammatory bowel disease (IBD) METHODS: Effectiveness and Safety of COVID-19 Vaccine in Patients with Inflammatory Bowel Disease (IBD) Treated with Immunomodulatory or Biological Drugs (ESCAPE-IBD) is a prospective, multicentre study promoted by the Italian Group for the study of Inflammatory Bowel Disease. We present data on serological response eight weeks after the second dose of COVID-19 vaccination in IBD patients and healthy controls (HCs).

RESULTS

1076 patients with IBD and 1126 HCs were analyzed. Seropositivity for anti-SARS-CoV-2 IgG was reported for most IBD patients, even if with a lesser rate compared with HCs (92.1% vs. 97.9%; p<0.001). HCs had higher antibody concentrations (median OD 8.72 [IQR 5.2-14-2]) compared to the whole cohort of IBD patients (median OD 1.54 [IQR 0.8-3.6]; p<0.001) and the subgroup of IBD patients (n=280) without any treatment or on aminosalicylates only (median OD 1.72 [IQR 1.0-4.1]; p<0.001).

CONCLUSIONS

Although most IBD patients showed seropositivity after COVID-19 vaccines, the magnitude of the humoral response was significantly lower than in HCs. Differently from other studies, these findings seem to be mostly unrelated to the use of immune-modifying treatments (ClinicalTrials.govID:NCT04769258).

Prevalence of Maternal Psychological Distress in pregnant women who receipt prenatal diagnosis of fetal Central Nervous System (CNS) anomalies

Introduction

Women receiving a prenatal diagnosis of fetal anomalies are a high-risk population for psychological distress leading to mood disorders. Even so, to date we have no evidence of studies who investigated the levels of maternal anxiety and depression in pregnant women receiving a prenatal diagnosis of fetal CNS anomalies.

Objectives

The aim of this study was to assess the prevalence of anxiety and depression levels in a pilot sample of pregnant women at the Prenatal Diagnostic Unit of the Bambino Gesù Children Hospital.

Methods

We collected data among 43 women who receipt fetal brain anomaly diagnosis (mean age: 35 yrs, SD ± 6.3, range 19-48 yrs; mean week at first access 26w, SD ± 3.9, range 18-33w). Prenatal diagnosis including: ventriculomegaly (37.2%), posterior cranial fossa (23.3%), choroid plexus cysts (11.6%), anomalies of CC (7%) and other (20.9%). Pregnancies with assisted reproductive technology were 14%. We use the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorders (GAD-7) questionnaires to assess anxious-depressive symptoms.

Results

showed a rate of mild-to-severe anxious depressive symptoms by 60.5% and 48.8% respectively. In detail: 41.9% mild, 14% moderate and 4.7% of severe anxiety. Meanwhile, 41.9% mild and 7% moderate depression. The prevalence of comorbid depressive and anxiety symptoms was 39.5% among the entire sample.

Conclusions

Preliminary data showed a high prevalence of anxious depressive symptoms and comorbidity among pregnant with CNS fetal anomalies. Women receiving a fetal CNS anomaly diagnosis may need additional psychological support or counselling.

Disclosure

No significant relationships.

Single-dose versus short-course prophylactic antibiotics for peroral endoscopic myotomy: a randomized controlled trial

BACKGROUND AND AIMS

Peroral endoscopic myotomy (POEM) has been recommended for achalasia treatment. To prevent the potential of infective risk, antibiotic prophylaxis is usually administered, whereas the additional need of antibiotic therapy after POEM is uncertain. The primary endpoint was to determine whether prophylaxis versus prophylaxis plus short therapy was needed after POEM.

METHODS

Consecutive patients scheduled for POEM were randomly assigned (1:1) to group A (prophylactic cefazolin 2 g IV) or group B (prophylaxis + cefazolin 2 g IV × 3 followed by oral amoxicillin/clavulanate 3 g/day). Infective risk was assessed by means of host response, namely body temperature and serum levels of white blood cells and C-reactive protein; immune response (the cytokines interleukin [IL]-6, IL-1β, and tumor necrosis factor-α and microbial translocation mediators lipopolysaccharide binding protein and soluble CD14); and blood cultures at time points before (t0) and after (t1, t2) POEM.

RESULTS

After POEM, none of the 124 enrolled patients (54.6 ± 12.6 years old; 64 men) developed any fever (body temperature: t0, 36.56± .49°C; t1, 36.53± .52°C; t2, 36.48± .41°C), without any differences between groups at any time point. Regarding systemic inflammation, no difference was reported between groups in serum levels of C-reactive protein and white blood cells. Considering microbial translocation mediated response, lipopolysaccharide binding protein (group A: t0, 1539 ± 168.6 pg/mL; t1, 1321 ± 149.1 pg/mL; t2, 2492 ± 283.2 pg/mL; group B: t0, 1318 ± 115.9 pg/mL; t1, 1492 ± 163.8 pg/mL; t2, 2600 ± 328.2 pg/mL) and soluble CD14 (group A: t0, 2.16 ± .15 μg/mL; t1, 1.89 ± .15 μg/mL; t2, 2.2 ± .15 μg/mL; group B: t0, 2.1 ± .13 μg/mL; t1, 2 ± .13 μg/mL; t2, 2.5 ± .2 μg/mL) were similar between the 2 groups; the immune response cytokines IL-6, IL-1β, and tumor necrosis factor-α also were similar in the 2 groups. In relation to blood cultures, at t1 the group B bacteremia rate was 3.2% (2/62) and group A was 1.6% (1/62) with no difference (P = .6). All subsequent blood cultures were negative at t2.

CONCLUSIONS

According to our study, postprophylactic short-term antimicrobial therapy after POEM is not required because of a very low residual infective risk. (Clinical trial registration number: NCT03587337.).

TL1A: A New Potential Target in the Treatment of Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), are chronic inflammatory diseases of the gastrointestinal tract. In the last few years, the development of biological agents targeting cytokines and receptors involved in IBD pathogenesis has led to better outcomes and has improved the course of the disease. Despite their effectiveness, drugs such as tumor necrosis factor (TNF) inhibitors, anti-Interleukin-12/23 and anti-integrins, do not induce a response in about one-third of patients, and 40% of patients lose response over time. Therefore, more efficient therapies are required. Recent studies showed that TL1A (Tumor necrosis factor-like cytokine 1A) acts as a regulator of mucosal immunity and participates in immunological pathways involved in the IBD pathogenesis. In this review article, we analyze the role of TL1A as a new potential target therapy in IBD patients.

Rediscovering histology: what is new in endoscopy for inflammatory bowel disease?

The potential of endoscopic evaluation in the management of inflammatory bowel diseases (IBD) has undoubtedly grown over the last few years. When dealing with IBD patients, histological remission (HR) is now considered a desirable target along with symptomatic and endoscopic remission, due to its association with better long-term outcomes. Consequently, the ability of endoscopic techniques to reflect microscopic findings in vivo without having to collect biopsies has become of upmost importance. In this context, a more accurate evaluation of inflammatory disease activity and the detection of dysplasia represent two mainstay targets for IBD endoscopists. New diagnostic technologies have been developed, such as dye-less chromoendoscopy, endomicroscopy, and molecular imaging, but their real incorporation in daily practice is not yet well defined. Although dye-chromoendoscopy is still recommended as the gold standard approach in dysplasia surveillance, recent research questioned the superiority of this technique over new advanced dye-less modalities [narrow band imaging (NBI), Fuji intelligent color enhancement (FICE), i-scan, blue light imaging (BLI) and linked color imaging (LCI)]. The endoscopic armamentarium might also be enriched by new video capsule endoscopy for monitoring disease activity, and high expectations are placed on the application of artificial intelligence (AI) systems to reduce operator-subjectivity and inter-observer variability. The goal of this review is to provide an updated insight on contemporary knowledge regarding new endoscopic techniques and devices, with special focus on their role in the assessment of disease activity and colorectal cancer surveillance.

Measuring anxiety and depression in parents of hospitalized children during the COVID-19 pandemic in a pediatric Italian hospital

Introduction

Parents of hospitalized children with chronic illness (HCCI) during the COVID-19 epidemic may face huge pressure and worry, leading to mental health issues. Parent’s depression and anxiety disorders increase the risk of mental health problems in the child and affect his/her recovery.

Objectives

The aim of this study was to assess the prevalence rate of depressive and anxiety symptoms among a pilot sample of parents of HCCI (in- and out-patients) with diagnosis of epilepsy (9), cystic fibrosis (8) and congenital heart anomalies (6) during COVID-19 pandemic. Pediatric patients were under a regular Children Hospital medical and psychological follow-up program.

Methods

We conducted a cross-sectional study among 23 Italian parents (15 F; 8 M) of HCCI during the COVID-19 epidemic period. We performed face-to face interviews and assessed depressive and anxiety symptoms with the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorders (GAD-7) questionnaire during scheduled follow up visits.

Results

The anxiety score of parents of HCCI was 4.43 ± 3.17, of which 39.1% of parents were anxious (≥5 points), while the depression score was 4.04 ± 2.67, of which 30.4% of parents show depressive symptoms (≥5 points). The prevalence of comorbid depressive and anxiety symptoms was 26.1% among the entire sample.

Conclusions

Preliminary data of our pilot study showed a high prevalence of anxious depressive symptoms and comorbidity among parents of HCCI. Timely provision of psychologic interventions are needed during and after COVID-19 pandemic in order to empower parenting and promote children recovery and quality of life.

Disclosure

No significant relationships.

Depression and anxiety in hospitalized children with epilepsy during COVID-19 pandemic: Preliminary findings of a cross-sectional study

Introduction

Anxious-depressive disorders are common among children with epilepsy. A recent Systematic Review and Meta-Analysis (Scott et al., 2020) reported that the overall pooled prevalence of anxiety disorders is 18.9% while of depressive disorders is 13.5%. COVID-19 pandemic has centralized the attention of governors and careers on the health emergency. As a result, the trajectory of the psychological care needs of this at risk population may have been neglected.

Objectives

The aim of the study was to assess the prevalence rate of depressive and anxiety symptoms among children with epilepsy during COVID-19 pandemic. Children were hospitalized in- and out-patients under a neurological and psychological follow up program in an Italian Children Hospital.

Methods

We conducted a cross-sectional study among 38 hospitalized children and adolescents with epilepsy (21F; 17M, mean age: 14,5; range: 11-18) during COVID-19 pandemic. We performed face-to face interviews and assessed depressive and anxiety symptoms with the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorders (GAD-7) questionnaire during scheduled follow up checks.

Results

Preliminary results showed a rate of mild-to-severe anxious depressive symptoms by 49.9% and 60.5% respectively. In detail: 21.1% mild, 15.7% moderate and 13.1% of severe anxiety, meanwhile 23.7% mild, 26.3% moderate and 10.5% of severe depression. The prevalence of comorbid depressive and anxiety symptoms was 39.5% among the entire sample.

Conclusions

Depressive and anxiety rates among hospitalized children with epilepsy during COVID-19 outbreak are very high. Pediatric services should deserve special attention to those patients’ mental health. Regular screening protocols and empowerment interventions in Hospital should be promoted.

Disclosure

No significant relationships.

Improving hospitalization in children and adolescents through animal assisted interventions (AAIS): A systematic review

Introduction

Animal Assisted Interventions (AAIs) are increasingly introduced in pediatric care settings as a mean to promote the physical, mental, and emotional well-being of hospitalized children and adolescents and the humanization of the hospital environment.

Objectives

The aim of this work was to review published studies implementing AAIs in hospital settings and to assess their effectiveness in reducing stress and pain, ameliorating social behavior, quality of life, and mood in pediatric patients. Reviewed interventions were also evaluated for their effects on caregiver’s stress and burden, as well as on perception of the work environment in hospital staff.

Methods

Studies were systematically searched using PubMed, Scopus, ProQuest and Web of Science databases in accordance with PRISMA guidelines. The search was aimed at identifying studies examining the effects of AAIs on behavioral and physiological response to stress in children and adolescents (0-18 years) formally admitted to a hospital for a stay, as well as in those undergoing a visit for treatments or medical examinations.

Results

Of 350 studies screened, 17 were eligible for inclusion. Most of them focused on stress, pain and anxiety reduction in pediatric patients, and used both physiological parameters and behavioral observations/scales. The vast majority of the studies employed dogs. Results show the potential of AAIs to reduce anxiety and behavioral distress in pediatric patients, while acting on physiological measures associated with arousal.

Conclusions

Although further studies of better quality are still needed, the findings of this review may have implications for clinical practices suggesting appropriate planning of AAIs by pediatric healthcare professionals.

Prevalence of depressive and anxiety symptoms in chronically ill children and adolescents during COVID-19 pandemic and lockdown: Preliminary findings of a pediatric hospital in Italy

Introduction

Psychological problems are common among the pediatric population suffering from a chronic illness, especially compared to the normal population. Stressful life events, such as social distancing measures implemented to counter the COVID-19 pandemic emergency, can strongly influence their epidemiology.

Objectives

The aim of this study was to assess the prevalence rate of depressive and anxiety symptoms among an Italian pediatric population affected by chronic illness and already under a Children Hospital psychological follow-up program during COVID-19 lockdown.

Methods

We conducted a cross-sectional study among 54 Italian children and adolescents affected by chronic illness (mean age: 15y; range: 8.9-18y) during the COVID-19 epidemic period. We assessed depressive and anxiety symptoms with the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorders (GAD-7) questionnaire during scheduled follow-up checks or teleconsulting.

Results

Preliminary results showed an elevated prevalence of depressive and anxiety symptoms (51% and 48% respectively) among chronically ill children during the COVID-19 outbreak. When compared with a non-ill pediatric population (Zhou et al. 2020), rates are + 7.3% higher for depression and + 10.6% for anxiety.

Conclusions

Chronic ill pediatric patients are a vulnerable group and require careful consideration. For this reason, the healthcare system should be able to implement and guarantee adequate mental health support programs and continuity of care. Further research is necessary since the COVID-19 outbreak could be repeated.

Thiopurines and non-melanoma skin cancer: partners in crime in inflammatory bowel diseases

INTRODUCTION

Several studies have shown that inflammatory bowel diseases (IBD) patients treated with thiopurines have an increased risk of developing skin cancer.

SOURCES OF DATA

This review is based on recent published literature regarding the use of thiopurines in IBD and skin malignancies.

AREAS OF AGREEMENT

Exposure to thiopurines is significantly associated with nonmelanoma skin cancer, but not with melanoma. Primary and secondary prevention including sun-protective measures and regular dermatologic screening are recommended in IBD patients, particularly in those exposed to thiopurines.

AREAS OF CONTROVERSY

Both when and how immunosuppressive therapy should be resumed in patients with a prior history of skin cancer still remain debatable topics.

GROWING POINTS

The benefit-risk balance between thiopurine therapy and risk of skin cancer should be evaluated in the drug decision process.

AREAS TIMELY FOR DEVELOPING RESEARCH

The approval of new effective strategies requires the re-evaluation of the positioning of thiopurines within the therapeutic algorithm based on an increasingly individualized approach.

PK, PD, and interactions: the new scenario with JAK inhibitors and S1P receptor modulators, two classes of small molecule drugs, in IBD

INTRODUCTION

Inflammatory bowel diseases (IBDs) are immune-mediated chronic inflammatory disorders of the gastrointestinal tract whose pathogenesis is not yet fully understood. Despite the advent of biological agents, there are still unmet needs for IBD patients, due to suboptimal rate of sustained remission achieved. Small molecule drugs (SMDs), the next generation of selective drugs in IBD, show promising results in ongoing trials.

AREAS COVERED

We describe the pharmacodynamics and pharmacokinetic features of novel SMDs and their main differences with biologic agents.

EXPERT OPINION

Small molecule drugs are a promising class of drugs for the treatment of ulcerative colitis and Crohn's disease with good results in inducing and maintaining remission. Hence, over the next few years physicians will have numerous options of small molecule drugs for the treatment of patients with IBD. This group of drugs are potentially easier to use over biological agents due to pharmacokinetic features such as oral administration, short half-life, high volume of distribution, and lack of immunogenicity. On the other hand, drug-drug interactions can happen with small-molecule drugs, principally due to competitive metabolic and clearance mechanisms.

Endoscopy after surgery in inflammatory bowel disease: Crohn's disease recurrence and pouch surveillance

INTRODUCTION

Crohn's disease (CD) and ulcerative colitis (UC) are immune-mediated disorders characterized by a chronic inflammation, with intermittent exacerbations of symptoms and inflammation. In both diseases, medical treatment has made revolutionary steps forward. Nevertheless, surgery is still required in many cases due to inefficacy of multiple medical therapies. It is not clear whether surgery rates in inflammatory bowel diseases (IBD) are currently decreasing despite all improvements.

AREAS COVERED

Multidisciplinary management is critical in surgical patients to improve long-term outcomes. Endoscopy plays a crucial role, both before and after surgery, in planning therapeutic strategies and stratifying risk of recurrence. Aim of this review is to provide a deeper insight into the central role of endoscopy in the postoperative management of IBD patients, focusing on recent research advances, future challenges and unresolved questions.

EXPERT OPINION

Both UC and CD surgical patients need endoscopy to define the correct therapeutic choice, predict subsequent disease course and adopt the correct surveillance strategy. In the next future, newer endoscopic techniques could be systematically applied in IBD patients after surgery, to assess early postoperative inflammation, response to treatment, or, regarding UC, to provide enhanced pouch surveillance, allowing for early detection of inflammation and dysplasia.

Positioning ustekinumab in moderate-to-severe ulcerative colitis: new kid on the block

Introduction: Ulcerative colitis (UC) is a chronic relapsing disorder of the colonic tract. Dysregulated innate and adaptive immune pathways contribute to intestinal inflammation in IBD, and cytokines, including IL-12 and IL-23, play a key role. The blockade of both IL-12 and IL-23 may have an impact on different pathways of inflammation and could be effective for the treatment of inflammatory bowel diseases.Ustekinumab is a fully human IgG1κ monoclonal antibody which binds to the shared p40 protein subunit of IL-12 and -23. It is currently approved for several immune-mediated diseases such as moderate to severe plaque psoriasis, psoriatic arthritis, and Crohn's disease, and has shown promising results in UC.Areas covered: A review of the literature was performed to understand several aspects including the role of IL-12 and -23 in UC, the potential therapeutic role of ustekinumab in inflammatory bowel disease, and the positioning of ustekinumab in the therapeutic algorithm of UC, based on extrapolated data from available randomized clinical trials.Expert opinion: Ustekinumab is effective and safe in UC, and shows potential advantages compared to other drugs in moderate-to-severe UC.

Psychological Characteristics of Inflammatory Bowel Disease Patients: A Comparison Between Active and Nonactive Patients

BACKGROUND AND AIMS

The role of new psychological factors such as psychopathological patterns and defense mechanisms in the care of inflammatory bowel disease (IBD) has been poorly investigated. We aimed to assess the psychological characteristics and defense mechanisms of IBD patients.

METHODS

This was a single-center, observational, cross-sectional study. Consecutive adult IBD patients were enrolled and stratified according to disease activity. Sociodemographic and clinical data were collected, and validated questionnaires (Symptom Checklist-90-R [SCL-90-R]) for psychological distress, Defense Mechanism Inventory (DMI) for psychological defense mechanisms, and Inflammatory Bowel Disease Questionnaire (IBDQ) for quality of life (QoL) were administered.

RESULTS

Two hundred one patients were enrolled: 101 in remission and 100 with active disease. The mean score for IBDQ was below the cutoff level (156.8 ± 37.8), with a significantly greater impairment of QoL in subjects with flares (136.5 vs 177.5, P < 0.001). Lower scores were associated with female gender. No patients had psychological scores above the cutoff for normality. Statistically higher SCL-90-R scores were found in active patients for obsessive-compulsive disorder (P = 0.026), depression (P = 0.013), anxiety (P = 0.013), phobic anxiety (P = 0.002), psychoticism (P = 0.007), global severity index (GSI) (P = 0.005) and positive symptom total (PST) (P = 0.001). A significantly increased probability of higher global indexes was associated with Crohn's disease and disease flares. None of the defensive Defense Mechanism Inventory (DMI) styles resulted above the cutoff in our cohort.

CONCLUSIONS

Further data are needed to demonstrate the potential key role of psychological intervention in the therapeutic strategies utilized for IBD patients, and the identification of specific psychological patterns based on the patients profile is necessary to optimize psychological intervention.

Activation of the VEGFC/VEGFR3 Pathway Induces Tumor Immune Escape in Colorectal Cancer

Colorectal cancer is a major cause of cancer-related death in Western countries and is associated with increased numbers of lymphatic vessels (LV) and tumor-associated macrophages (TAM). The VEGFC/VEGFR3 pathway is regarded as the principal inducer of lymphangiogenesis and it contributes to metastases; however, no data are available regarding its role during primary colorectal cancer development. We found that both VEGFC and VEGFR3 were upregulated in human nonmetastatic colorectal cancer, with VEGFR3 expressed on both LVs and TAMs. With the use of three different preclinical models of colorectal cancer, we also discovered that the VEGFC/VEGFR3 axis can shape both lymphatic endothelial cells and TAMs to synergistically inhibit antitumor immunity and promote primary colorectal cancer growth. Therefore, VEGFR3-directed therapy could be envisioned for the treatment of nonmetastatic colorectal cancer. SIGNIFICANCE: The prolymphangiogenic factor VEGFC is abundant in colorectal cancer and activates VEGFR3 present on cancer-associated macrophages and lymphatic vessels; activation of VEGFR3 signaling fosters cancer immune escape, resulting in enhanced tumor growth.

Lymphatic endothelium contributes to colorectal cancer growth via the soluble matrisome component GDF11

Colorectal cancer (CRC) is one of the most malignant tumors worldwide. Stromal cells residing in the tumor microenvironment strongly contribute to cancer progression through their crosstalk with cancer cells and extracellular matrix. Here we provide the first evidence that CRC-associated lymphatic endothelium displays a distinct matrisome-associated transcriptomic signature, which distinguishes them from healthy intestinal lymphatics. We also demonstrate that CRC-associated human intestinal lymphatic endothelial cells regulate tumor cell growth via growth differentiation factor 11, a soluble matrisome component which in CRC patients was found to be associated with tumor progression. Our data provide new insights into lymphatic contribution to CRC growth, aside from their conventional role as conduits of metastasis.

Protumor Steering of Cancer Inflammation by p50 NF-κB Enhances Colorectal Cancer Progression

Although tumor-associated macrophages (TAM) display a M2-skewed tumor-promoting phenotype in most cancers, in colorectal cancer, both TAM polarization and its impact remain controversial. We investigated the role of the M2-polarizing p50 NF-κB subunit in orchestrating TAM phenotype, tumor microenvironment composition, and colorectal cancer progression. We first demonstrated, by parallel studies in colitis-associated cancer (CAC) and in genetically driven Apc^Min mouse models, that the p50-dependent inhibition of M1-polarized gut inflammation supported colorectal cancer development. In accordance with these studies, p50^-/- mice displayed exacerbated CAC with fewer and smaller tumors, along with enhanced levels of M1/Th1 cytokines/chemokines, including IL12 and CXCL10, whose administration restrained CAC development in vivo The inflammatory profile supporting tumor resistance in colons from p50^-/- tumor bearers correlated inversely with TAM load and positively with both recruitment of NK, NKT, CD8⁺ T cells and number of apoptotic tumor cells. In agreement, myeloid-specific ablation of p50 promoted tumor resistance in mice, whereas in colorectal cancer patients, a high number of p50⁺ TAMs at the invasive margin was associated with decreased IL12A and TBX21 expression and worse postsurgical outcome. Our findings point to p50 involvement in colorectal cancer development, through its engagement in the protumor activation of macrophages, and identify a candidate for prognostic and target therapeutic intervention. Cancer Immunol Res; 6(5); 578-93. ©2018 AACR.

Full Interchangeability in Regard to Immunogenicity Between the Infliximab Reference Biologic and Biosimilars CT-P13 and SB2 in Inflammatory Bowel Disease

BACKGROUND

Infliximab (IFX) biosimilars CT-P13 and SB2 have comparable efficacy, safety, and immunogenicity to the originator Remicade (RMC). However, concerns about cross-switching patients between the 3 brands were raised in the absence of cross reactivity data between them. We aimed to determine whether antibodies to infliximab (ATI) in inflammatory bowel disease (IBD) patients cross-react with RMC, CT-P13, and SB2.

METHODS

Based on previous ATI status, samples from 34 patients participating in the BIOSIM01 study (13 RMC, 9 CT-P13, and 12 switchers) were selected. Patients were treated with either RMC only, or CT-P13 only, or with RMC switched to CT-P13. Additionally, 28 IFX-naïve patients were assayed as controls. In total, 180 samples were analyzed. ATI trough levels were measured in parallel with 3 different bridging Enzyme Linked Immunosorbent Assays constructed using the 3 drugs. Spearman's coefficient and percentages of agreement were used to study the correlation between each assay.

RESULTS

In total, 76 samples out of 152 IFX-treated patient samples were ATI-positive (30 RMC, 14 CT-P13, and 32 switchers). All resulted ATI-positive when either CT-P13 or SB2 bridging assays were used. The overall percentage of agreement was 100% when compared either with CT-P13 or SB2 assays. No significant differences were found among ATI levels and coefficients (Spearman's 0.98 to 1.0, P < 0.0001).

CONCLUSIONS

ATI of RMC-treated, CT-P13-treated or RMC to CT-P13 switched patients show full cross-reactivity with CT-P13 and SB2. Findings suggest that immunodominant epitopes in the reference and CT-P13 drugs are equally present in SB2. Data support full interchangeability between biosimilars in regard to immunogenicity.

MFSD2A Promotes Endothelial Generation of Inflammation-Resolving Lipid Mediators and Reduces Colitis in Mice

BACKGROUND & AIMS

Alterations in signaling pathways that regulate resolution of inflammation (resolving pathways) contribute to pathogenesis of ulcerative colitis (UC). The resolution process is regulated by lipid mediators, such as those derived from the ω-3 docosahexaenoic acid (DHA), whose esterified form is transported by the major facilitator superfamily domain containing 2A (MFSD2A) through the endothelium of brain, retina, and placenta. We investigated if and how MFSD2A regulates lipid metabolism of gut endothelial cells to promote resolution of intestinal inflammation.

METHODS

We performed lipidomic and functional analyses of MFSD2A in mucosal biopsies and primary human intestinal microvascular endothelial cells (HIMECs) isolated from surgical specimens from patients with active, resolving UC and healthy individuals without UC (controls). MFSD2A was knocked down in HIMECs with small hairpin RNAs or overexpressed from a lentiviral vector. Human circulating endothelial progenitor cells that overexpress MFSD2A were transferred to CD1 nude mice with dextran sodium sulfate-induced colitis, with or without oral administration of DHA.

RESULTS

Colonic biopsies from patients with UC had reduced levels of inflammation-resolving DHA-derived epoxy metabolites compared to healthy colon tissues or tissues with resolution of inflammation. Production of these metabolites by HIMECs required MFSD2A, which is required for DHA retention and metabolism in the gut vasculature. In mice with colitis, transplanted endothelial progenitor cells that overexpressed MFSD2A not only localized to the inflamed mucosa but also restored the ability of the endothelium to resolve intestinal inflammation, compared with mice with colitis that did not receive MFSD2A-overexpressing endothelial progenitors.

CONCLUSIONS

Levels of DHA-derived epoxides are lower in colon tissues from patients with UC than healthy and resolving mucosa. Production of these metabolites by gut endothelium requires MFSD2A; endothelial progenitor cells that overexpress MFSD2A reduce colitis in mice. This pathway might be induced to resolve intestinal inflammation in patients with colitis.

The safety of biological pharmacotherapy for the treatment of ulcerative colitis

INTRODUCTION

Biological agents are effective in ulcerative colitis (UC). Currently, 3 anti-TNF agents (infliximab, adalimumab, and golimumab) and 1 anti-integrin agent (vedolizumab) are approved for the treatment of UC. The mechanism of action of biologic agents can also give rise to several side effects, some even serious. It remains uncertain to what extent biologic treatments may be associated with an increased rate of infections, malignancies and other adverse events Areas covered: Our aim is to review the relevant data available in the literature and briefly summarize the safety profile of biological therapy in UC. We performed a literature search using the OVID, MEDLINE, PUBMED and EMBASE databases. Also other relevant sources of safety data were also used. Expert opinion: All biological agents currently used in UC are relatively safe. Accurate prevention measures and screening prior to start such therapies, and regular surveillance programs are strongly recommend to minimize any risk of infections, malignancy and other adverse events related to the use of monoclonal antibodies in UC patients.

Haematopoietic prolyl hydroxylase-1 deficiency promotes M2 macrophage polarization and is both necessary and sufficient to protect against experimental colitis

Prolyl hydroxylase domain-containing proteins (PHDs) regulate the adaptation of cells to hypoxia. Pan-hydroxylase inhibition is protective in experimental colitis, in which PHD1 plays a prominent role. However, it is currently unknown how PHD1 targeting regulates this protection and which cell type(s) are involved. Here, we demonstrated that Phd1 deletion in endothelial and haematopoietic cells (Phd1^f/f Tie2:cre) protected mice from dextran sulphate sodium (DSS)-induced colitis, with reduced epithelial erosions, immune cell infiltration, and colonic microvascular dysfunction, whereas the response of Phd2^f/+ Tie2:cre and Phd3^f/f Tie2:cre mice to DSS was similar to that of their littermate controls. Using bone marrow chimeras and cell-specific cre mice, we demonstrated that ablation of Phd1 in haematopoietic cells but not in endothelial cells was both necessary and sufficient to inhibit experimental colitis. This effect relied, at least in part, on skewing of Phd1-deficient bone marrow-derived macrophages towards an anti-inflammatory M2 phenotype. These cells showed an attenuated nuclear factor-κB-dependent response to lipopolysaccharide (LPS), which in turn diminished endothelial chemokine expression. In addition, Phd1 deficiency in dendritic cells significantly reduced interleukin-1β production in response to LPS. Taken together, our results further support the development of selective PHD1 inhibitors for ulcerative colitis, and identify haematopoietic cells as their primary target. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

IL-23 Blockade for Crohn s disease: next generation of anti-cytokine therapy

INTRODUCTION

Adaptive immunity in intestinal inflammation may play a key role in the pathogenesis of Crohn's disease. In particular, interleukin (IL)-23 may be a key mediator in chronic intestinal inflammation by inducing the differentiation of naïve CD4 + T cells into Th17, with the production of several pro-inflammatory cytokines. Furthermore, IL-23 induces interferon-γ (IFN- γ) production from activated T cells, a critical cytokine in innate and adaptive immunity against infections. Areas covered: We aim to review the available data from literature regarding the role of IL-23, with a more specific focus on the recent progresses in the therapeutic modulation of this cytokine. Expert commentary: Increased knowledge regarding the role of IL-23 has allowed for the development of effective therapeutic progresses by blocking the IL-23 mediated pathways. Primary or secondary loss of response to anti-TNF therapies in Crohn's disease patients during the first year is widely described in literature: the development of new drugs, with alternative mechanisms of action, is thus a key point to consider for the optimal management of these subjects. Drugs blocking the IL-12/23 pathway showed a good efficacy and safety profile in immune-mediated diseases Further studies are necessary regarding the role of the single blockade of IL-23.

Vascular endothelial growth factor C disrupts the endothelial lymphatic barrier to promote colorectal cancer invasion

BACKGROUND & AIMS

Colorectal cancer (CRC) is highly metastatic. Metastases spread directly into local tissue or invade distant organs via blood and lymphatic vessels, but the role of lymphangiogenesis in CRC progression has not been determined. Lymphangiogenesis is induced via vascular endothelial growth factor C (VEGFC) activation of its receptor, VEGFR3; high levels of VEGFC have been measured in colorectal tumors undergoing lymphangiogenesis and correlated with metastasis. We investigated VEGFC signaling and lymphatic barriers in human tumor tissues and mice with orthotopic colorectal tumors.

METHODS

We performed immunohistochemical, immunoblot, and real-time polymerase chain reaction analyses of colorectal tumor specimens collected from patients; healthy intestinal tissues collected during operations of patients without CRC were used as controls. CT26 CRC cells were injected into the distal posterior rectum of BALB/c-nude mice. Mice were given injections of an antibody against VEGFR3 or an adenovirus encoding human VEGFC before orthotopic tumors and metastases formed. Lymph node, lung, and liver tissues were collected and evaluated by flow cytometry. We measured expression of vascular endothelial cadherin (CDH5) on lymphatic vessels in mice and in human intestinal lymphatic endothelial cells.

RESULTS

Levels of podoplanin (a marker of lymphatic vessels), VEGFC, and VEGFR3 were increased in colorectal tumor tissues, compared with controls. Mice that expressed VEGFC from the adenoviral vector had increased lymphatic vessel density and more metastases in lymph nodes, lungs, and livers, compared with control mice. Anti-VEGFR3 antibody reduced numbers of lymphatic vessels in colons and prevented metastasis. Expression of VEGFC compromised the lymphatic endothelial barrier in mice and endothelial cells, reducing expression of CDH5, increasing permeability, and increasing trans-endothelial migration by CRC cells. Opposite effects were observed in mice and cells when VEGFR3 was blocked.

CONCLUSIONS

VEGFC signaling via VEGFR3 promotes lymphangiogenesis and metastasis by orthotopic colorectal tumors in mice and reduces lymphatic endothelial barrier integrity. Levels of VEGFC and markers of lymphatic vessels are increased in CRC tissues from patients, compared with healthy intestine. Strategies to block VEGFR3 might be developed to prevent CRC metastasis in patients.

The urokinase plasminogen activator receptor (uPAR) controls macrophage phagocytosis in intestinal inflammation

OBJECTIVE

Inflammation plays crucial roles in the pathogenesis of several chronic inflammatory disorders, including Crohn's disease (CD) and UC, the two major forms of IBD. The urokinase plasminogen activator receptor (uPAR) exerts pleiotropic functions over the course of both physiological and pathological processes. uPAR not only has a key role in fibrinolysis but also modulates the development of protective immunity. Additionally, uPAR supports extracellular matrix degradation and regulates cell migration, adhesion and proliferation, thus influencing the development of inflammatory and immune responses. This study aimed to evaluate the role of uPAR in the pathogenesis of IBD.

DESIGN

The functional role of uPAR was assessed in established experimental models of colitis. uPAR deficiency effects on cytokine release, polarisation and bacterial phagocytosis were analysed in colonic macrophages. uPAR expression was analysed in surgical specimens collected from normal subjects and patients with IBD.

RESULTS

In mice, uPAR expression is positively regulated as colitis progresses. uPAR-KO mice displayed severe inflammation compared with wild-type littermates, as indicated by clinical assessment, endoscopy and colon histology. The absence of uPAR led to an increased production of inflammatory cytokines by macrophages that showed an M1 polarisation and impaired phagocytosis. In human IBD, CD68(+) macrophages derived from the inflamed mucosa expressed low levels of uPAR.

CONCLUSIONS

These findings point to uPAR as an essential component of intestinal macrophage functions and unravel a new potential target to control mucosal inflammation in IBD.

The triggering receptor expressed on myeloid cells (TREM) in inflammatory bowel disease pathogenesis

The Triggering Receptors Expressed on Myeloid cells (TREM) are a family of cell-surface molecules that control inflammation, bone homeostasis, neurological development and blood coagulation. TREM-1 and TREM-2, the best-characterized receptors so far, play divergent roles in several infectious diseases. In the intestine, TREM-1 is highly expressed by macrophages, contributing to inflammatory bowel disease (IBD) pathogenesis. Contrary to current understanding, TREM-2 also promotes inflammation in IBD by fueling dendritic cell functions. This review will focus specifically on recent insights into the role of TREM proteins in IBD development, and discuss opportunities for novel treatment approaches.

VEGF-C-dependent stimulation of lymphatic function ameliorates experimental inflammatory bowel disease

Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory bowel diseases (IBDs) of unknown etiology that are associated with an aberrant mucosal immune response. Neoangiogenesis and vascular injury are observed in IBD along with increased lymphangiogenesis. While the pathogenic role of angiogenesis in IBD is well characterized, it is not clear how or if increased lymphangiogenesis promotes disease. Here, we determined that enhancing lymphangiogenesis and lymphatic function reduces experimental IBD. Specifically, we demonstrated that adenoviral induction of prolymphangiogenic factor VEGF-C provides marked protection against the development of acute and chronic colitis in 2 different animal models. VEGF-C-dependent protection was observed in combination with increased inflammatory cell mobilization and bacterial antigen clearance from the inflamed colon to the draining lymph nodes. Moreover, we found that the VEGF-C/VEGFR3 pathway regulates macrophage (MΦ) plasticity and activation both in cultured MΦs and in vivo, imparting a hybrid M1-M2 phenotype. The protective function of VEGF-C was meditated by the so-called resolving MΦs during chronic experimental colitis in a STAT6-dependent manner. Together, these findings shed light on the contribution of lymphatics to the pathogenesis of gut inflammation and suggest that correction of defective lymphatic function with VEGF-C has potential as a therapeutic strategy for IBD.

Identification of serum and tissue micro-RNA expression profiles in different stages of inflammatory bowel disease

The altered expression of micro-RNA (miRNA) has been associated with Crohn's disease (CD) and ulcerative colitis (UC). The aim of this study was to establish specific miRNA expression patterns in the serum and mucosa of inflammatory bowel disease (IBD) patients (UC and CD with colonic involvement) at different stages of the disease. Serum and biopsies from nine active CD (aCD), nine inactive CD (iCD), nine active UC (aUC) and nine inactive UC (iUC) and serum from 33 healthy subjects were collected. Up to 700 miRNAs were evaluated by the TaqMan human miRNA array. The ΔCt values were obtained using the mean expression values of all expressed miRNAs in a given sample as a normalization factor for miRNA real-time quantitative polymerase chain reaction data. The levels of serum miRNAs in CD and UC patients were different to healthy subjects. Thirteen serum miRNAs were expressed commonly in CD and UC patients. Two miRNAs were higher and four miRNAs were lower in the serum of aCD than iCD. No serum miRNA was regulated exclusively in aUC compared with iUC patients. Four miRNAs were higher and three miRNAs were lower in the mucosa of aCD than iCD. Two miRNAs were higher and three miRNAs were lower in the mucosa of aUC than iUC. No serum miRNAs coincided with tissue miRNAs in aCD and aUC patients. Our results suggest the existence of specific miRNA expression patterns associated with IBD and their different stages and support the utility of miRNA as possible biomarkers. This pilot study needs to be validated in a large prospective cohort.

Bacterial sensor triggering receptor expressed on myeloid cells-2 regulates the mucosal inflammatory response

BACKGROUND AND AIMS

Triggering receptor expressed on myeloid cells (TREM)-2 is a surface receptor detected on macrophages, dendritic cells, and microglia that binds repeated anionic motifs on yeast and Gram-positive and Gram-negative bacteria. Little is known about TREM-2 expression and function in the intestine or its role in inflammatory bowel disease (IBD). We investigated the expression of TREM-2 in the intestinal lamina propria and its role in the development of colonic inflammation.

METHODS

We measured levels of TREM-2 in lamina propria mononuclear cells from surgical specimens collected from patients with IBD or cancer (controls). We analyzed the development of colitis in TREM-2 knockout and wild-type mice. Colon samples were isolated from mice and analyzed for cytokine expression, phagocytosis of bacteria, proliferation in colonic crypts, lamina propria mononuclear cell function, and T-cell activation by ovalbumin.

RESULTS

TREM-2 was virtually absent from colon samples of control patients, but levels were significantly higher in within the inflamed mucosa of patients with IBD; it was mainly expressed by CD11c(+) cells. Levels of TREM-2 increased as acute or chronic colitis was induced in mice. TREM-2 knockout mice developed less severe colitis than wild-type mice; the knockout mice lost less body weight, had a lower disease activity index, and had smaller mucosal lesions in endoscopic analysis. Colon dendritic cells from TREM-2 knockout mice produced lower levels of inflammatory cytokines and had reduced levels of bacterial killing and T-cell activation than cells from wild-type mice.

CONCLUSIONS

TREM-2 contributes to mucosal inflammation during development of colitis in mice. Levels of TREM-2 are increased within the inflamed mucosa of patients with IBD, indicating its potential as a therapeutic target.

Enhanced platelet adhesion induces angiogenesis in intestinal inflammation and inflammatory bowel disease microvasculature

Although angiogenesis is viewed as a fundamental component of inflammatory bowel disease (IBD) pathogenesis, we presently lack a thorough knowledge of the cell type(s) involved in its induction and maintenance in the inflamed intestinal mucosa. This study aimed to determine whether platelet (PLT) adhesion to inflamed intestinal endothelial cells of human origin may favour angiogenesis. Unstimulated or thrombin-activated human PLT were overlaid on resting or tumour necrosis factor (TNF)-α-treated human intestinal microvascular endothelial cells (HIMEC), in the presence or absence of blocking antibodies to either vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-1, integrin α_vβ₃, tissue factor (TF) or fractalkine (FKN). PLT adhesion to HIMEC was evaluated by fluorescence microscopy, and release of angiogenic factors (VEGF and soluble CD40L) was measured by ELISA. A matrigel tubule formation assay was used to estimate PLT capacity to induce angiogenesis after co-culturing with HIMEC. TNF-α up-regulated ICAM-1, α_vβ₃ and FKN expression on HIMEC. When thrombin-activated PLT were co-cultured with unstimulated HIMEC, PLT adhesion increased significantly, and this response was further enhanced by HIMEC activation with TNF-α. PLT adhesion to HIMEC was VCAM-1 and TF independent but ICAM-1, FKN and integrin α_vβ₃ dependent. VEGF and sCD40L were undetectable in HIMEC cultures either before or after TNF-α stimulation. By contrast, VEGF and sCD40L release significantly increased when resting or activated PLT were co-cultured with TNF-α-pre-treated HIMEC. These effects were much more pronounced when PLT were derived from IBD patients. Importantly, thrombin-activated PLT promoted tubule formation in HIMEC, a functional estimate of their angiogenic potential. In conclusion, PLT adhesion to TNF-α-pre-treated HIMEC is mediated by ICAM-1, FKN and α_vβ₃, and is associated with VEGF and sCD40L release. These findings suggest that inflamed HIMEC may recruit PLT which, upon release of pro-angiogenic factors, actively contribute to inflammation-induced angiogenesis.

Infliximab therapy inhibits inflammation-induced angiogenesis in the mucosa of patients with Crohn's disease

OBJECTIVES

Inflammation-driven angiogenesis contributes to the pathogenesis of inflammatory bowel disease (IBD). In line with this, the efficacy of inhibitors of angiogenesis has been demonstrated in experimental models of colitis. Currently, the ability of infliximab, an anti-tumor necrosis factor-α (TNF-α) agent that is highly beneficial in patients with IBD, to affect mucosal angiogenesis in patients with Crohn's disease (CD) and ulcerative colitis (UC) is unknown.

METHODS

Patients with active CD (n=14) were treated with infliximab for 1 year, and peripheral blood and intestinal mucosa samples were collected before and after treatment. Mucosal angiogenesis was evaluated by CD31 and Ki-67 staining in endoscopic biopsies at baseline (week 0) and at week 54. The release of vascular endothelial growth factor-A (VEGF-A) by cultured mucosal extracts was measured by enzyme-linked immunosorbent assay (ELISA), before and after administration of infliximab, as well as in cultures of human intestinal fibroblasts (HIFs) stimulated with TNF-α in the presence or absence of infliximab. Migration of human intestinal microvascular endothelial cells (HIMECs) was investigated by migration assays.

RESULTS

Microvessel density was significantly higher in the mucosa from patients with CD compared with tissue from healthy control individuals. Of the 14 patients, 8 (57%) showed a clinical remission in response to infliximab, which was associated with a significant reduction of microvascular density. Morphometric vessel analysis further confirmed the significant reduction of the area of vascular section after administration of infliximab. Furthermore, the expression levels of the proliferation marker Ki-67 in endothelial cells were significantly reduced after treatment. The mucosal concentration of VEGF-A was also significantly decreased, whereas in vitro exposure of HIF to infliximab virtually abolished TNF-α-induced VEGF-A production. These phenomena did not occur in patients who showed no clinical response to infliximab.

CONCLUSIONS

Administration of infliximab downregulates mucosal angiogenesis in patients with CD and restrains production of VEGF-A by mucosal fibroblasts. It is proposed that this ameliorates inflammation-driven angiogenesis in the gut mucosa and contributes to the therapeutic efficacy of blockade of TNF-α.

Leukocyte traffic control: a novel therapeutic strategy for inflammatory bowel disease

Inflammatory bowel diseases share common pathogenetic mechanisms that are not yet completely understood. It is clear, however, that the expression and production of cytokines in response to inflammation plays a key role in mediating the migration of activated leukocytes. The process of angiogenesis and the expression of adhesion molecules on the intestinal microvasculature act as gateways, facilitating the recruitment of leukocytes into the gut mucosa. New agents specifically blocking adhesion molecules, in particular integrins, have been developed in order to limit the passage of activated leukocytes into the mucosa. Non-gut-specific anti-integrin agents, such as natalizumab, have been shown to be effective in the treatment of IBD, but the risk of serious adverse events has limited their further development. The development of a new specific molecule, vedolizumab, is currently under investigation in a large clinical trial. This novel specific anti-integrin drug seems to hold promise in the treatment of gut inflammation.

Intestinal fibrosis in Crohn's disease: medical treatment or surgery?

Crohn's disease (CD) is a chronic panenteric disease of unknown aethiology tending to progress, inspite medical or surgical treatment. Intestinal fibrosis is among the most common complications of CD, resulting in stricture formation in the small intestine and colon. About 75% of CD patients will undergo surgery at least once over the course of their disease and fibrotic strictures represents the main indication for surgery and the first cause of hospitalization and costs for CD patients. Clinical management of intestinal strictures depends on the type of stricture: inflammatory strictures are treated medically and are usually responsive to treatment, while fibrotic strictures require surgery. Clinical decisions regarding the right treatment choice for such conditions require proper knowledge on what to expect from the emerging drug strategies and surgical techniques. To achieve optimal results in patients management an approach combining the expertise of both gastroenterologist and colorectal surgeon is essential. This review aims at providing clinicians with an overview on fibrotic strictures in CD patients particular focus will be placed on the principal imaging modalities, and the medical, endoscopic and surgical treatment options with relative indications, according to the most recent evidence available.

Mucosal biomarkers in inflammatory bowel disease: Key pathogenic players or disease predictors?

Inflammatory bowel diseases (IBDs) are chronic inflammatory disorders of the bowel, including ulcerative colitis and Crohn’s disease. A single etiology has not been identified, but rather the pathogenesis of IBD is very complex and involves several major and minor contributors, employing different inflammatory pathways which have different roles in different patients. Although new and powerful medical treatments are available, many are biological drugs or immunosuppressants, which are associated with significant side effects and elevated costs. As a result, the need for predicting disease course and response to therapy is essential. Major attempts have been made at identifying clinical characteristics, concurrent medical therapy, and serological and genetic markers as predictors of response to biological agents. Only few reports exist on how mucosal/tissue markers are able to predict clinical behavior of the disease or its response to therapy. The aim of this paper therefore is to review the little information available regarding tissue markers as predictors of response to therapy, and reevaluate the role of tissue factors associated with disease severity, which can eventually be ranked as “tissue factor predictors”. Five main categories are assessed, including mucosal cytokines and chemokines, adhesion molecules and markers of activation, immune and non-immune cells, and other mucosal components. Improvement in the design and specificity of clinical studies are mandatory to be able to classify tissue markers as predictors of disease course and response to specific therapy, obtain the goal of achieving “personalized pathogenesis-oriented therapy” in IBD.

Emerging biologics in the treatment of inflammatory bowel disease: what is around the corner?

Inflammatory bowel diseases (IBD) are idiopathic chronic inflammations: the etiology of Crohn's disease (CD) and ulcerative colitis (UC) is still largely unknown. Environmental and genetic factors in combination with the microbial flora or specific microorganisms trigger an event, leading to the activation of an intestinal immune response. Immune and non-immune cells create a cross talk via the secretion of soluble mediators and expression of cell adhesion molecules, resulting in further cell activation. Mediators such as cytokines and chemokines play a role in cell recruitment and polarization, intercellular signal amplification or activation and differentiation. Considering these aspects, medical management of inflammatory bowel disease has changed considerably over the past decade. Advances in biotechnology has allowed for the introduction of many biologic therapies, other than anti-TNF therapies. Many of these drugs showed clinical benefit for induction and maintenance therapy, both in UC and CD. Although numerous, at present only monoclonal anti-TNF antibodies are currently available worldwide. Other biological agents have been tested or are under evaluation. This paper systematically reviews the mechanism-of-action, efficacy, short-term and, where available, long-term safety of biological agents that have been approved for the treatment of IBD or are under evaluation which target different molecules other than tumor necrosis factor alpha (TNF-alpha).

The lymphatic system controls intestinal inflammation and inflammation-associated Colon Cancer through the chemokine decoy receptor D6

BACKGROUND AND AIMS

Inflammatory CC chemokines have long been associated with cancer, but unequivocal evidence of a role in clinically relevant models of carcinogenesis is lacking. D6, a promiscuous decoy receptor that scavenges inflammatory CC chemokines, plays a non-redundant role in reducing the inflammatory response in various organs. As inflammation is a key player in the development of inflammatory bowel disease (IBD) and IBD-associated colorectal cancer, we investigated D6 expression in human colitis and colon cancer, and its role in experimental colitis and inflammation-associated colon cancer.

RESULTS

In humans, D6 was mainly expressed by lymphatic vessels and leukocytes in the mucosa of individuals with IBD and colon cancer, as well as the mucosa of control individuals. Mice lacking expression of D6 were significantly more susceptible to experimental colitis than wild-type mice and failed to resolve colitis, with significantly higher levels of several pro-inflammatory chemokines. In bone marrow chimeric mice, the ability of D6 to regulate colitis was tracked to the stromal/lymphatic compartment, with no contribution of haemopoietic cells. Finally, after administration of the carcinogen azoxymethane, D6(-/-) mice showed increased susceptibility to colitis-associated cancer in the distal segment of the colon compared with wild-type mice.

CONCLUSIONS

D6 expressed on lymphatic vessels plays a key role in the control of intestinal inflammation and the development of inflammation-associated colon cancer. Our results reveal a new unexpected role for the lymphatic system in the pathogenesis of IBD and intestinal cancer, and candidate chemokines as novel players in tumour promotion and progression.

Molecular signaling blockade as a new approach to inhibit leukocyte-endothelial interactions for inflammatory bowel disease treatment

Mitogen-activated protein kinases (MAPK) are among the major widespread transduction pathways in humans. They are involved in several inflammatory disorders, including the pathogenesis of inflammatory bowel disease (IBD). A recent paper showed that activated MAPK are upregulated on endothelium and fibroblasts from intestinal biopsies of active IBD patients. In vitro experiments demonstrated that MAPK activation on intestinal endothelial cells and fibroblasts are responsible for the production of certain chemokines, increased leukocyte adhesion and transmigration. Specific local inhibition of MAPK activity on endothelial cells and fibroblasts may provide a new mechanism to control mucosal inflammation and leukocyte recruitment into the intestine of active IBD patients.

Unique role of junctional adhesion molecule-a in maintaining mucosal homeostasis in inflammatory bowel disease

BACKGROUND & AIMS

Junctional adhesion molecule-A (JAM-A) is localized at the tight junctions and controls leukocyte migration into the tissues. However, its functional role in inflammatory bowel disease (IBD) is unexplored.

METHODS

Control, Crohn's disease (CD), and ulcerative colitis (UC) tissue specimens were studied for JAM-A expression, as well as the colon of mice given dextran sodium sulfate (DSS). Wild-type and JAM-A(-/-), Tie-2-Cre-JAM-A(-/-) (endothelial/hematopoietic-specific JAM inactivation) mice were studied for susceptibility to DSS. Disease activity and colonic inflammation were assessed using a disease activity index histology and endoscopy, and mucosal cytokines were measured by enzyme-linked immunosorbent assay. JAM-A function was investigated by RNA silencing in epithelial cells, and apoptosis was measured.

RESULTS

In both CD and UC, as well as in experimental colitis, there is a loss of epithelial but not endothelial JAM-A expression. Deletion of JAM-A results in a dramatic increase in susceptibility to DSS colitis, as assessed by weight loss, disease activity index, histologic and endoscopic severity, and strikingly high mortality rates. This is not caused by the absence of JAM-A in the endothelial or hematopoietic compartments because Tie-2-Cre-JAM-A(-/-) mice are no more susceptible to DSS colitis than wild-type animals. JAM-A(-/-) mice displayed increased intestinal permeability and inflammatory cytokine production, and marked epithelial apoptosis. Silencing of JAM-A in intestinal epithelial cells resulted in increased permeability in vitro.

CONCLUSIONS

Our results show a nonredundant and novel role of JAM-A in controlling mucosal homeostasis by regulating the integrity and permeability of epithelial barrier function.

Multiple pathogenic roles of microvasculature in inflammatory bowel disease: a Jack of all trades

The etiology of Crohn's disease and ulcerative colitis, the two major forms of inflammatory bowel disease (IBD), is still largely unknown. However, it is now clear that the abnormalities underlying pathogenesis of intestinal inflammation are not restricted to those mediated by classic immune cells but also involve nonimmune cells. In particular, advances in vascular biology have outlined a central and multifaceted pathogenic role for the microcirculation in the initiation and perpetuation of IBD. The microcirculation and its endothelial lining play a crucial role in mucosal immune homeostasis through tight regulation of the nature and magnitude of leukocyte migration from the intravascular to the interstitial space. Chronically inflamed IBD microvessels display significant alterations in microvascular physiology and function compared with vessels from healthy and uninvolved IBD intestine. The investigation into human IBD has demonstrated how endothelial activation present in chronically inflamed IBD microvessels results in a functional phenotype that also includes leakiness, chemokine and cytokine expression, procoagulant activity, and angiogenesis. This review contemplates the newly uncovered contribution of intestinal microcirculation to pathogenesis and maintenance of chronic intestinal inflammation. In particular, we assess the multiple roles of the microvascular endothelium in innate immunity, leukocyte recruitment, coagulation and perfusion, and immune-driven angiogenesis in IBD.