Faecal calprotectin or lactoferrin can identify postoperative recurrence in Crohn's disease.

BACKGROUND: Identifying Crohn's disease recurrence in symptomatic patients after ileocaecal resection is difficult. The aim of this study was to evaluate faecal concentrations of granulocyte degradation products in this setting. METHODS: A postoperative cohort of 13 patients was followed prospectively for 1 year with regular faecal calprotectin (FC) and lactoferrin (FL) measurements. A second postoperative cohort (median 24 months after resection) of 104 patients provided a single stool sample. Faecal measurements were compared with symptom diaries, the Harvey Bradshaw Index, endoscopic examination, C-reactive protein and platelet measurement. RESULTS: In the uncomplicated course, both markers normalized within 2 months. Both FC and FL correlated significantly with Harvey Bradshaw Index (P < 0.001). Twenty-eight patients with severely clinically active disease had high mean(s.e.) levels of FC (661.1(119.1) microg/g) and FL (116.6(32.2) microg/g); and 43 with clinically inactive disease had low levels of FC (70.2(27.1) microg/g) and FL (5.9(2.4) microg/g). In patients with mild to moderately clinically active disease, FC and FL identified individuals with and without recurrent inflammatory disease. Faecal markers were more accurate at predicting clinical disease activity than C-reactive protein, platelet count or endoscopic appearance. CONCLUSION: FC and FL are non-invasive tests that can help to identify disease recurrence in symptomatic postoperative patients.

Is the etiology of eosinophilic esophagitis in adults a response to allergy or reflux injury? Study of cellular proliferation markers.

Recent research suggests that allergy may be the key factor in the etiology of eosinophilic esophagitis (EE); however, historically, the condition was hypothesized as related to reflux injury to the esophageal mucosa. We studied this hypothesis by comparing markers of inflammation and cellular proliferation in EE and reflux esophagitis. Lower esophageal biopsies of adult patients with EE (n = 10), reflux esophagitis (n = 8), and normal controls (n = 13) were assessed quantitatively for the expression of the cyclooxygenase-2 (COX-2) enzyme, cellular proliferation, and oncogenic resistance to apoptosis using monoclonal antibodies for COX-2, Ki-67, and Bcl-2, respectively. Normal esophageal epithelium demonstrated weak diffuse uptake of COX-2 stain in the basal layer. No COX-2 expression was demonstrated in the EE group, significantly less than the control and reflux groups (P < 0.01 and P < 0.001, respectively). Cellular proliferation measured by Ki-67 expression was higher in EE and reflux compared with control (P < 0.001 and P < 0.01). Ki-67 expression, and thus degree of hyperplasia, appeared greater in EE than reflux, but was not statistically significant (P = 0.228). The degree of apoptosis was similar in all study groups. EE and reflux esophagitis are proliferative conditions expressing Ki-67 in higher concentrations than control. Mucosal proliferation in reflux esophagitis is COX-2 dependent. This novel research in EE has demonstrated downregulation of COX-2 expression compared with reflux esophagitis and control. We hypothesize that the allergy-related cytokine IL-13 known to inhibit COX-2 expression and found in high concentrations in EE as responsible for this. The pathogenesis of EE is likely dependent on allergy rather than reflux injury to the esophagus.

Quantifying Autophagic Structures in Mammalian Cells Using Confocal Microscopy.

Autophagy relies on the sequential, hierarchical association of proteins with phagophores, and forming autophagosomes to allow completion of the process. Additionally, the trafficking of the unique transmembrane autophagy-related protein ATG9 is vital for autophagy progression. In this chapter, we discuss methods to monitor autophagosome number using confocal microscopy, by following the association of different autophagosomal markers with the phagophore and completed autophagosome. We also discuss methods to monitor the trafficking of ATG9 in mammalian cells under starvation conditions.

Five novel hormone-responsive cell lines derived from murine mammary ductal carcinomas: in vivo and in vitro effects of estrogens and progestins.

We have developed an experimental model of mammary carcinogenesis in which the administration of medroxyprogesterone acetate (MPA) to female BALB/c mice induces progestin-dependent ductal metastatic mammary tumors with high levels of estrogen receptor (ER) and progesterone receptor (PR). Through selective transplants in untreated mice, we have obtained progestin-independent variants, still expressing high levels of ER and PR. Primary cultures of the MPA-induced carcinomas C4-HD and C7-HI were set up, and after 3-4 months, several different cell lines were obtained. Four of these, MC4-L1, MC4-L2, MC4-L3, and MC4-L5 were established from C4-HD and a fifth, MC7-L1, from C7-HI. All cells were of epithelial origin, as demonstrated by electron microscopy and by immunocytochemical identification of cytokeratin and cadherin. In vitro MC4-L1, MC4-L3, and MC4-L5 showed a typical epithelial morphology; when transplanted in vivo, they originated metastatic carcinomas with different degrees of differentiation. MC4-L2 and MC7-L1 deviated from the standard epithelial picture; they disclosed a spindle-shaped morphology in vitro and in vivo gave rise to a biphasic spindle cell/tubular carcinoma and an anaplastic carcinoma, respectively; both lines gave rise to metastases. This differential morphology correlated with a higher degree of aggressiveness, as compared with MC4-L1, MC4-L3, and MC4-L5. ERs and PRs were detected by binding, immunocytochemistry, and Western blot. In vitro, MC4-L2 and MC7-L1 were stimulated by MPA (nM to microM) and 17beta-estradiol (nM and 10 nM); no significant stimulation was observed in MC4-L1, MC4-L3, and MC4-L5 under the same experimental conditions. In vivo, MPA significantly stimulated tumor growth in all epithelioid lines but not in MC4-L2 and MC7-L1. A progestin-dependent growth pattern was confirmed for MC4-L1, MC4-L3, and MC4-L5 in successive transplants, whereas MC4-L2 and MC7-L1 behaved as progestin independent. This is the first description of mouse mammary carcinoma cell lines expressing ER and PR. The different in vitro hormone responses as compared with in vivo and the differential effects of 17beta-estradiol in the parental tumors and in cell lines render these lines useful tools for the in vitro and in vivo study of hormone regulation of tumor growth and metastases.

Implementation of a 'care bundle' improves the management of patients admitted to hospital with decompensated cirrhosis.

BACKGROUND: Since 1970, there has been a 400% increase in liver-related deaths due to the increasing prevalence of chronic liver disease in the United Kingdom (UK). The 2013 UK National Confidential Enquiry into Patient Outcome and Death report found that only 47% of patients who died from alcohol-related liver disease received 'good care' during their hospital stay. AIM: To develop a 'care bundle' for patients with decompensated cirrhosis, aiming to ensure that evidence-based treatments are delivered within the first 24 h of hospital admission. METHODS: This work gives practical advice about how to implement the bundle and examines its effects on patient care at three National Health Service Hospital Trusts in the UK by collecting data on patient care before and after introduction of the bundle. RESULTS: Data were collected on 228 patients across three centres (59% male, median age 53 years). Alcohol-related liver disease was the aetiology of chronic liver disease in 85% of patients. The overall mortality rate during hospital admission was 15%. The audits demonstrated improvements in patient care for patients with a completed care bundle who were significantly more likely to have a diagnostic ascitic performed within the first 24 h (P = 0.020), have an accurate alcohol history documented (P < 0.0001) and be given antibiotics as prophylaxis against infection following a variceal haemorrhage (P = 0.0096). In Newcastle, the bundle completion rate increased from 25% to 90% during the review periods. CONCLUSIONS: The introduction of a care bundle was associated with increased rates of diagnostic paracentesis and antibiotic prophylaxis with variceal haemorrhage in patients with decompensated cirrhosis.

Relapse after withdrawal from anti-TNF therapy for inflammatory bowel disease: an observational study, plus systematic review and meta-analysis.

BACKGROUND: Infliximab and adalimumab have established roles in inflammatory bowel disease (IBD) therapy. UK regulators mandate reassessment after 12 months' anti-TNF therapy for IBD, with consideration of treatment withdrawal. There is a need for more data to establish the relapse rates following treatment cessation. AIM: To establish outcomes following anti-TNF withdrawal for sustained remission using new data from a large UK cohort, and assimilation of all available literature for systematic review and meta-analysis. METHODS: A retrospective observational study was performed on 166 patients with IBD (146 with Crohn's disease (CD) and 20 with ulcerative colitis [UC) and IBD unclassified (IBDU)] withdrawn from anti-TNF for sustained remission. Meta-analysis was undertaken of all published studies incorporating 11 further cohorts totalling 746 patients (624 CD, 122 UC). RESULTS: Relapse rates in the UK cohort were 36% by 1 year and 56% by 2 years for CD, and 42% by 1 year and 47% by 2 years for UC/IBDU. Increased relapse risk in CD was associated with age at diagnosis [hazard ratio (HR) 2.78 for age <22 years], white cell count (HR 3.22 for >5.25 × 109 /L) and faecal calprotectin (HR 2.95 for >50 µg/g) at drug withdrawal. Neither continued immunomodulators nor endoscopic remission were predictors. In the meta-analysis, estimated 1-year relapse rates were 39% and 35% for CD and UC/IBDU respectively. Retreatment with anti-TNF was successful in 88% for CD and 76% UC/IBDU. CONCLUSIONS: Assimilation of all available data reveals remarkable homogeneity. Approximately one-third of patients with IBD flare within 12 months of withdrawal of anti-TNF therapy for sustained remission.

What causes the isolation effect?

Events that are incongruent with their prevailing context are usually very well remembered. This fact often is described as the distinctiveness effect in memory, an effect that has served as explanation not only of memory phenomena but also of various other phenomena, including social judgment. The core laboratory paradigm for studying distinctiveness in memory research has long been the isolation paradigm. This paradigm, sometimes attributed to H. von Restorff, yields better memory for an item categorically isolated from surrounding items than for the surrounding items and a proper control item. The authors offer an interpretation of the isolation effect based on the analysis of the processing of similarities and differences among the items. Two experiments provide evidence for this interpretation. The results are discussed in the context of current theories of distinctiveness effects in memory. An appeal is made for a different conceptualization of distinctiveness effects, one that treats distinctiveness as a discriminative process in memory that requires processing of both similarities and differences among items.

Giving patients 'perceived control' over psoriasis: advice for optimizing the physician-patient relationship.

Patients with psoriasis suffer from the effects of a chronic illness. One of the most bothersome aspects of the disease is a sense of loss of 'control.' 'Perceived control' is an important and well-studied psychological concept. The literature on perceived control offers guidance to help improve the physician-patient relationship and outcomes in chronic diseases such as psoriasis. Practical suggestions include the use of materials and other resources offered by patient advocacy groups (such as those from the National Psoriasis Foundation) and the development of a physician-patient relationship that gives the patient a sense of control of their disease.

Thiopurine withdrawal during sustained clinical remission in inflammatory bowel disease: relapse and recapture rates, with predictive factors in 237 patients.

BACKGROUND: Thiopurines (azathioprine and mercaptopurine) remain integral to most medical strategies for maintaining remission in Crohn's disease (CD) and ulcerative colitis (UC). Indefinite use of these drugs is tempered by long-term risks. While clinical relapse is noted frequently following drug withdrawal, there are few published data on predictive factors. AIM: To investigate the success of planned thiopurine withdrawal in patients in sustained clinical remission to identify rates and predictors of relapse. METHODS: This was a multicentre retrospective cohort study from 11 centres across the UK. Patients included had a definitive diagnosis of IBD, continuous thiopurine use ≥3 years and withdrawal when in sustained clinical remission. All patients had a minimum of 12 months follow-up post drug withdrawal. Primary and secondary end points were relapse at 12 and 24 months respectively. RESULTS: 237 patients were included in the study (129 CD; 108 UC). Median duration of thiopurine use prior to withdrawal was 6.0 years (interquartile range 4.4-8.4). At follow-up, moderate/severe relapse was observed in 23% CD and 12% UC patients at 12 months, 39% CD and 26% UC at 24 months. Relapse rate at 12 months was significantly higher in CD than UC (P = 0.035). Elevated CRP at withdrawal was associated with higher relapse rates at 12 months for CD (P = 0.005), while an elevated white cell count was predictive at 12 months for UC (P = 0.007). CONCLUSION: Thiopurine withdrawal in the context of sustained remission is associated with a 1-year moderate-to-severe relapse rate of 23% in Crohn's disease and 12% in ulcerative colitis.

Measurement of faecal calprotectin and lactoferrin in inflammatory bowel disease.

Crohn's disease and ulcerative colitis are chronic relapsing gastrointestinal conditions characterised by an influx of inflammatory cells to the affected gut mucosa. The mainstay of diagnosing and re-evaluating these conditions in clinical practice and research is by invasive serological, radiological, endoscopic and histological assessment. In clinical trials, disease activity is often evaluated using a combination of the above tests plus clinical indices such as the Crohn's Disease Activity Index and Ulcerative Colitis Activity Index. These tools rely on subjective assessment of symptoms and so, often, do not correlate with mucosal inflammation or mucosal healing, which may be the preferred therapeutic end point for long-term inflammatory bowel disease (IBD) management. The faecal biomarkers calprotectin and lactoferrin are neutrophil derived proteins that are stable in faeces and can be detected by quantitative ELISA in small stool samples. Concentrations of both are raised in patients with gastrointestinal mucosal inflammation. They provide a unique, inexpensive, non-invasive method of testing for active inflammatory disease. They can be used to screen for IBD and as a surrogate marker of mucosal healing they are useful in monitoring the response to therapeutic intervention or surgery. They may also predict the clinical course of the disease. This clinical review aims to discuss the current evidence, limitations and potential future uses of these biomarkers in IBD.

Clinical lesson: eosinophilic oesophagitis, a new diagnosis to swallow.

Eosinophilic oesophagitis (EoE) is a recently described condition that has gained increasing recognition over the past 5 years. Despite this, many clinicians remain unaware of EoE, often leading to diagnostic delay and therefore significant morbidity. The diagnosis of EoE should be considered in any patient with a history of intermittent or continuous dysphagia, or oesophageal food impaction. It should be strongly suspected in young patients, particularly men, presenting with dysphagia and a history of atopy. Here, three patients are presented that highlight common features of EoE. In addition, a clinical review of the worldwide literature is provided to heighten physician awareness and understanding of the condition.

Anti-tissue transglutaminase antibodies in the follow-up of adult coeliac disease.

BACKGROUND: The detection of auto antibodies directed against tissue transglutaminase (anti-tTG antibodies) has a well-established role in the diagnosis of coeliac disease, but the value of these antibodies in long-term follow-up is controversial. AIMS: To determine if serial anti-tTG antibody measurements could confirm adherence to a gluten-free diet (GFD) and identify patients at risk of disease complications. METHODS: In a 54-month cohort follow-up study, 182 adult patients were assessed. Data recorded included self-assessment of GFD adherence; anti-tTG antibody concentration and serum ferritin, vitamin B12 and folate. Where available, bone mineral density (BMD) and duodenal histology data were retrieved. RESULTS: Persistently elevated anti-tTG antibody levels were significantly associated with abnormal duodenal histology (P < 0.001), low ferritin (P < 0.01) and poor adherence to the GFD (P < 0.001). The specificity was >85% while the sensitivity was 39-60%. Anti-tTG antibody concentrations fell rapidly following successful initiation of a GFD, and maintenance of normalization identified those who continued to be adherent to the diet. CONCLUSIONS: This study supports a strategy of using anti-tTG antibody concentrations to monitor newly diagnosed and established patients with coeliac disease, and to target dietetic intervention to reduce the risk of complication.

Assembly and transport properties of invariant chain trimers and HLA-DR-invariant chain complexes.

The MHC class II-associated invariant chain behaves as a resident endoplasmic reticulum protein in the absence of class II molecules. In humans, two predominant forms exist; one, p35, differs from the other, p33, by an N-terminal cytoplasmic extension of 16 amino acids that contains a strong endoplasmic reticulum-retention signal. Here we show that one mechanism for retention of p33 is its association with p35 in mixed invariant chain trimers. However, even for p33 homotrimers transport from the endoplasmic reticulum is inefficient. In an MHC class II-positive B cell line, the formation of invariant chain trimers is rapid and is the first intermediate in the assembly of a nine-chain alpha beta-invariant chain complex. With time, three higher molecular weight complexes are progressively formed. These correspond to an invariant chain trimer with one alpha beta dimer, two alpha beta dimers, and three alpha beta dimers, respectively. No free alpha beta dimers are detectable early in biosynthesis. However, beginning at 2 h of chase, alpha beta dimers begin to appear concomitant with the disappearance of the completely assembled alpha beta-invariant chain complex. This conversion is virtually complete by 4 h, and presumably reflects the proteolytic degradation of the invariant chain component of the alpha beta-invariant chain complex and the generation of endosomal alpha beta dimers capable of binding antigenic peptides.

Transport properties of free and MHC class II-associated oligomers containing different isoforms of human invariant chain.

Major histocompatibility complex (MHC) class II molecules are heterodimers of alpha and beta subunits that associate intracellularly with the invariant chain. Human invariant chain exists in four forms, p33, p35, p41, and p43, generated by a combination of alternative initiation of translation and alternative splicing. The biological significance of the existence of the different forms of invariant chain is still unclear and to date no study has compared all four using one system. We have compared them for their transport characteristics and for their ability to transport associated MHC class II heterodimers into the endocytic pathway. Here we report that hetero oligomers containing p33 and p35 or p41 and p43 remain in the endoplasmic reticulum (ER) in the absence of class II alpha and beta chains. This is consistent with earlier reports suggesting that the N-terminal extension shared by p35 and p43 contains an ER retention signal. Homo oligomers containing only the p33 or p41 forms of invariant chain exit the ER and are sorted to endosomes following passage through the Golgi apparatus. Their accumulation leads to enlargement of the endosomes. Quantitation of the turnover rates of the p35/p33 forms with the alternatively spliced p43/p41 forms indicates that the latter are more stable, both in the ER and following transport through the Golgi apparatus. When class II molecules are co-expressed with p33 and p35, or p41 and p43, the assembled complex is efficiently transported to the endocytic pathway.

Invariant chain targets HLA class II molecules to acidic endosomes containing internalized influenza virus.

The role of the HLA class II-associated invariant chain in the intracellular trafficking of HLA-DR molecules was examined in a transient expression system using HeLa cells. In the absence of alpha and beta polypeptides, invariant chain was retained in the endoplasmic reticulum (ER). In the absence of invariant chain, intracellular alpha beta heterodimers could be detected only in the ER and the Golgi apparatus. However, when alpha and beta subunits were coexpressed with invariant chain, HLA-DR molecules were detectable in peripheral cytoplasmic vesicles, which also contained invariant chain. In addition, an antibody directed to an acid-induced conformational determinant on the influenza hemagglutinin molecule detected internalized influenza virus in the HLA-DR-containing vesicles. These findings provide direct evidence that the invariant chain targets class II molecules to an acidic endosomal compartment and that this compartment, long suspected to be the site of antigen processing, is the site where class II molecules interact with natural antigen.

Intracellular transport and peptide binding properties of HLA class II glycoproteins.

Protein antigens internalized by an antigen presenting cell are degraded into peptides, a subset of which binds to the class II glycoproteins encoded by the major histocompatibility complex to form epitopes recognized by specific T cells. Current evidence suggests that the immunogenic peptides are generated in an endosomal, acidic compartment containing internalized antigen, proteinases, and exocytic class II molecules. These exocytic class II glycoproteins are associated during transport from the endoplasmic reticulum to the endosomal compartment with an additional glycoprotein, the invariant chain. Proteolytic degradation of the invariant chain in the endosomal compartment dissociates it from the class II glycoproteins, which only then acquire the capacity to bind peptides. After peptide binding occurs, the class II-peptide complexes are transported to the antigen-presenting cell surface for recognition by T cells.