Factors associated with early outcomes following standardised therapy in children with ulcerative colitis (PROTECT): a multicentre inception cohort study

Background Previous retrospective studies of paediatric ulcerative colitis have had limited ability to describe disease progression and identify predictors of treatment response. In this study, we aimed to identify characteristics associated with outcomes following standardised therapy after initial diagnosis. Methods The PROTECT multicentre inception cohort study was based at 29 centres in the USA and Canada and included paediatric patients aged 4?17 years who were newly diagnosed with ulcerative colitis. Guided by the Pediatric Ulcerative Colitis Activity Index (PUCAI), patients received initial standardised treatment with mesalazine (PUCAI 10?30) oral corticosteroids (PUCAI 35?60), or intravenous corticosteroids (PUCAI ò65). The key outcomes for this analysis were week 12 corticosteroid-free remission, defined as PUCAI less than 10 and taking only mesalazine, and treatment escalation during the 12 study weeks to anti-tumour necrosis factor à (TNFà) agents, immunomodulators, or colectomy among those initially treated with intravenous corticosteroids. We identified independent predictors of outcome through multivariable logistic regression using a per-protocol approach. This study is registered with ClinicalTrials.gov, number NCT01536535. Findings Patients were recruited between July 10, 2012, and April 21, 2015. 428 children initiated mesalazine (n=136), oral corticosteroids (n=144), or intravenous corticosteroids (n=148). Initial mean PUCAI was 31ú1 (SD 13ú3) in children initiating with mesalazine, 50ú4 (13ú8) in those initiating oral corticosteroids, and 66ú9 (13ú7) in those initiating intravenous corticosteroids (p<0ú0001 for between-group comparison). Week 12 outcome data were available for 132 patients who initiated with mesalazine, 141 with oral corticosteroids, and 143 with intravenous corticosteroids. Corticosteroid-free remission with the patient receiving mesalazine treatment only at 12 weeks was achieved by 64 (48%) patients in the mesalazine group, 47 (33%) in the oral corticosteroid group, and 30 (21%) in the intravenous corticosteroid group (p<0ú0001). Treatment escalation was required by nine (7%) patients in the mesalazine group, 21 (15%) in the oral corticosteroid group, and 52 (36%) in the intravenous corticosteroid group (p<0ú0001). Eight patients, all of whom were initially treated with intravenous corticosteroids, underwent colectomy. Predictors of week 12 corticosteroid-free remission were baseline PUCAI less than 35 (odds ratio 2ú44, 95% CI 1ú41?4ú22; p=0ú0015), higher baseline albumin by 1 g/dL increments among children younger than 12 years (4ú05, 1ú90?8ú64; p=0ú00030), and week 4 remission (6ú26, 3ú79?10ú35; p<0ú0001). Predictors of treatment escalation by week 12 in patients initially treated with intravenous corticosteroids included baseline total Mayo score of 11 or higher (2ú59, 0ú93?7ú21; p=0ú068 [retained in model due to clinical relevance]), rectal biopsy eosinophil count less than or equal to 32 cells per high power field (4ú55, 1ú62?12ú78; p=0ú0040), rectal biopsy surface villiform changes (3ú05, 1ú09?8ú56; p=0ú034), and not achieving week 4 remission (30ú28, 6ú36?144ú20; p<0ú0001). Interpretation Our findings provide guidelines to assess the response of children newly diagnosed with ulcerative colitis to standardised initial therapy and identify predictors of treatment response and failure. These data suggest that additional therapeutic interventions might be warranted to improve early outcomes, especially in patients presenting with severe disease and requiring intravenous corticosteroids. Funding National Institutes of Health

Clinical and biological predictors of response to standardised paediatric colitis therapy (PROTECT): a multicentre inception cohort study

Background: Lack of evidence-based outcomes data leads to uncertainty in developing treatment regimens in children who are newly diagnosed with ulcerative colitis. We hypothesised that pretreatment clinical, transcriptomic, and microbial factors predict disease course. Methods: In this inception cohort study, we recruited paediatric patients aged 4?17 years with newly diagnosed ulcerative colitis from 29 centres in the USA and Canada. Patients initially received standardised mesalazine or corticosteroids, with pre-established criteria for escalation to immunomodulators (ie, thiopurines) or anti-tumor necrosis factor-à (TNFà) therapy. We used RNA sequencing to define rectal gene expression before treatment, and 16S sequencing to characterise rectal and faecal microbiota. The primary outcome was week 52 corticosteroid-free remission with no therapy beyond mesalazine. We assessed factors associated with the primary outcome using logistic regression models of the per-protocol population. This study is registered with ClinicalTrials.gov, number NCT01536535. Findings: Between July 10, 2012, and April 21, 2015, of 467 patients recruited, 428 started medical therapy, of whom 400 (93%) were evaluable at 52 weeks and 386 (90%) completed the study period with no protocol violations. 150 (38%) of 400 participants achieved week 52 corticosteroid-free remission, of whom 147 (98%) were taking mesalazine and three (2%) were taking no medication. 74 (19%) of 400 were escalated to immunomodulators alone, 123 (31%) anti-TNFà therapy, and 25 (6%) colectomy. Low baseline clinical severity, high baseline haemoglobin, and week 4 clinical remission were associated with achieving week 52 corticosteroid-free remission (n=386, logistic model area under the curve [AUC] 0ú70, 95% CI 0ú65?0ú75; specificity 77%, 95% CI 71?82). Baseline severity and remission by week 4 were validated in an independent cohort of 274 paediatric patients with newly diagnosed ulcerative colitis. After adjusting for clinical predictors, an antimicrobial peptide gene signature (odds ratio [OR] 0ú57, 95% CI 0ú39?0ú81; p=0ú002) and abundance of Ruminococcaceae (OR 1ú43, 1ú02?2ú00; p=0ú04), and Sutterella (OR 0ú81, 0ú65?1ú00; p=0ú05) were independently associated with week 52 corticosteroid-free remission. Interpretation: Our findings support the utility of initial clinical activity and treatment response by 4 weeks to predict week 52 corticosteroid-free remission with mesalazine alone in children who are newly diagnosed with ulcerative colitis. The development of personalised clinical and biological signatures holds the promise of informing ulcerative colitis therapeutic decisions. Funding: US National Institutes of Health

Lysosomal proteome analysis reveals that CLN3-defective cells have multiple enzyme deficiencies associated with changes in intracellular trafficking

Numerous lysosomal enzymes and membrane proteins are essential for the degradation of proteins, lipids, oligosaccharides, and nucleic acids. The CLN3 gene encodes a lysosomal membrane protein of unknown function, and CLN3 mutations cause the fatal neurodegenerative lysosomal storage disorder CLN3 (Batten disease) by mechanisms that are poorly understood. To define components critical for lysosomal homeostasis that are affected by this disease, here we quantified the lysosomal proteome in cerebellar cell lines derived from a CLN3 knock-in mouse model of human Batten disease and control cells. We purified lysosomes from SILAC-labeled, and magnetite-loaded cerebellar cells by magnetic separation and analyzed them by MS. This analysis identified 70 proteins assigned to the lysosomal compartment and 3 lysosomal cargo receptors, of which most exhibited a significant differential abundance between control and CLN3-defective cells. Among these, 28 soluble lysosomal proteins catalyzing the degradation of various macromolecules had reduced levels in CLN3-defective cells. We confirmed these results by immunoblotting and selected protease and glycosidase activities. The reduction of 11 lipid-degrading lysosomal enzymes correlated with reduced capacity for lipid droplet degradation and several alterations in the distribution and composition of membrane lipids. In particular, levels of lactosylceramides and glycosphingolipids were decreased in CLN3-defective cells, which were also impaired in the recycling pathway of the exocytic transferrin receptor. Our findings suggest that CLN3 has a crucial role in regulating lysosome composition and their function, particularly in degrading of sphingolipids, and, as a consequence, in membrane transport along the recycling endosome pathway

Of bats and bodies: methods for reading and writing embodiment

Military memoirs are embodied texts of war. They therefore pose particular challenges to scholars who work with them, as they seem to insist on the uniqueness of particular wartime experiences and the impossibility of communicating these embodied experiences to a wider public. In this article I unpack some of the tensions in the ways that war scholarship approaches these ‘flesh-witness accounts’ and argue that these can productively be challenged, in ways that open up new possibilities for research methods. I begin by explaining what is meant by ‘flesh-witnessing’ and the significance of corporeal experience in constructing particular stories about war. From this I argue that while placing significance on embodiment when studying war is crucial, embodiment is not a concept that should be assigned to others ‘over there’, without also acknowledging how it works within ‘us’ ‘back home’ as civilians and scholars. Rather, embodiment as a concept compels us to analyse its numerous ‘entanglements’, which in turn challenge us to rethink the relationship between the ‘author’ and the ‘reader’ of military memoirs. Reflecting on my own work with these memoirs, and learning to pay attention to what I do and feel as I read and write, I chart a series of methods for reading and writing embodiment

Desensitisation of neutrophil responses by systemic interleukin 8 in cystic fibrosis.

BACKGROUND--Inflammation associated with neutrophil infiltration is a commonly observed feature of children with cystic fibrosis. Production of the major neutrophil chemotactic cytokine interleukin 8 (IL-8) is potentially of great importance in the pathology of cystic fibrosis. Concentrations of IL-8 in both sputum and bronchoalveolar lavage fluid have been found to be higher in children with cystic fibrosis than in controls. The IL-8 induced chemotactic response and numbers of IL-8 receptors on peripheral neutrophils obtained from children with cystic fibrosis have been compared with a control group of children. METHODS--Cells were isolated from 18 patients with cystic fibrosis (aged 4-20 years) and 13 controls (aged 5-12 years) by dextran centrifugation followed by separation on Lymphoprep. Chemotaxis was assayed using multiwell microchemotaxis chambers and 5 microns polycarbonate filters. Filters were fixed and stained with Haema-Gurr for counting. Results were expressed as numbers of neutrophils per high power field (HPF). RESULTS--At the optimum concentration (1 x 10(-8) mol/l) the number of cells migrating were similar for controls (150 (12)/HPF) and for the cystic fibrosis group (140 (14)/HPF)). At lower concentrations the numbers of neutrophils migrating were lower for the cystic fibrosis group. Scatchard analysis of 125I-labelled IL-8 binding revealed lower numbers of receptors on neutrophils from patients with cystic fibrosis (22,000 per cell) than from controls (75,000 per cell). CONCLUSIONS--Reduced responsiveness to IL-8 of neutrophils from patients with cystic fibrosis is associated with receptor desensitisation as a result of exposure to high systemic levels of IL-8