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Background: Better prognostic measures for ulcerative colitis (UC) could significantly advance patient care. While the prognostic capacity of circulating proteins in UC has been explored, the role of mucosal proteins remains largely unknown. We examined mucosal protein markers in patients with incident ulcerative colitis and evaluated their prognostic value. Methods: Biopsies from macroscopically inflamed colonic/rectal mucosa of adult patients in the Swedish inception cohort of IBD (SIC IBD) were obtained at diagnosis of UC. Patients were followed prospectively, and clinical data were recorded after 3 and 12 months. Disease course was categorised as indolent or aggressive at 12 months, based on a composite outcome of colectomy, hospital admission for active disease, treatment refractoriness towards ≥2 biological agents; the use of >2 courses of corticosteroids, or a cumulative dose of >2.5 g. Relative estimates of 162 protein markers were assessed in homogenised tissue supernatants, using proximity extension assay technology (Olink Proteomics, Uppsala, Inflammation and Oncology II panel). Mann-Whitney U test, with Benjamini-Hochberg correction was used to identify differentially regulated mucosal proteins in aggressive vs indolent disease course, with a 5% false discovery rate (FDR). Smoothly clipped absolute deviation regularised logistic regression models were used to identify prognostic signatures distinguishing aggressive from indolent disease course. Performance was estimated in a leave-one-out cross-validation and reported as the area under the receiver operating characteristic (ROC) curve (AUC). Results: 117 patients provided a macroscopically inflamed colonic/rectal biopsy at diagnosis of UC. Basic demographics and clinical characteristics are presented in Table 1. Relative protein levels of WFdc2 and CCL20 were significantly lower in lysates from patients developing an aggressive course vs patients developing an indolent course, while estimates of MM

Background: Mental health (MH) has been reported to be poorer among patients with inflammatory bowel disease (IBD) than general population. However, it is not known whether MH is more driven by inflammation itself or related to gastrointestinal (GI) symptoms. Also, the dynamics of MH following IBD diagnosis is not well understood. Methods: In the Swedish Inception Cohort of IBD (SIC-IBD), patients with Crohn’s disease (CD), ulcerative colitis (UC) and unclassified IBD (IBD-U) as well as symptomatic controls (SC) and healthy controls (HC) filled in Patient Health Questionnaire-9 (PHQ-9), a validated screening tool for depression. Patients completed PHQ-9 at diagnosis and at one year follow-up while the controls completed it once. Disease outcome was defined at one year based on requirement of advanced treatments/ surgery. Results: In total, 286 individuals (16 HC, 89 SC, 62 CD, 104 UC, 15 IBD-U) completed the questionnaire at baseline. HC had significantly lower PHQ-9 score, (fewer depressive symptoms), at baseline compared to all the other groups (p<0.01). The baseline PHQ-9 score was not significantly different between SC and CD, UC and IBD-U patients (p=0.06). At one year follow-up, 38 CD and 53 UC patients completed the PHQ-9. Between baseline and follow-up, UC patients had a significant drop in their PHQ-9 score (p<0.0000001), whereas CD patients did not have any significant change in their PHQ-9 score (p=0.06). Furthermore, UC patients had significantly lower PHQ-9 score compared with CD patients at follow-up (p=0.04, Figure 1). Baseline PHQ-9 score was not correlated with calprotectin at baseline neither in UC nor CD patients (p=0.7 and 0.5 respectively). Also, there was no positive correlation between PHQ-9 score change and calprotectin change in either UC or CD patients, and neither baseline nor follow-up PHQ-9 scores were significantly different in patients with poor or good outcome (p>0.05). When analysed separately by sex, there was still no corr

Background: We aimed to identify protein signatures predictive of a future diagnosis of inflammatory bowel disease (IBD). Methods: We conducted a case-control study, nested within large population-based cohorts with biorepositories. Samples were obtained from individuals who later in life were diagnosed with IBD (preclinical cases) and compared with age and sex-matched individuals who remained free from IBD during follow-up (controls). Using proximity extension assays (Olink, Uppsala), we measured 176 proteins. We applied regularized logistic regression to identify protein signatures of preclinical disease in serum from the discovery cohort (n=312). Their performance was validated in an external preclinical cohort (n=222). The biological relevance of identified proteins was further assessed in an inception cohort (n=144). Finally, we used an IBD twin cohort (n=327) to examine the impact of genetic and shared environmental factors on identified proteins. Results: We identified 34 proteins associated with preclinical Crohn’s disease (CD) in the discovery cohort (Pfalse discovery rate <0.10), with 9 confirmed in the validation cohort (Pfalse discovery rate <0.05). For preclinical ulcerative colitis (UC), 45 proteins were identified and 12 validated (Fig. 1A-B). In the discovery cohort, a signature of 29 proteins differentiated preclinical CD cases from controls with an AUC of 0.85 (Fig. 1G). Its performance was confirmed when applied to the preclinical validation cohort (AUC=0.84, Fig. 1H). Moreover, the signature had excellent capacity to differentiate newly diagnosed CD from healthy controls in the inception cohort (AUC = 0.99, Fig. 1I). The preclinical UC signature had a significant, but albeit lower, predictive capacity in the discovery (AUC=0.77), validation (AUC=0.67) and inception cohort (AUC=0.90, Fig. 1G-I).15 of 17 proteins associated with preclinical IBD demonstrated significantly higher intra-pair correlation coefficients in healthy monozygotic- compa

The polar bear (Ursus maritimus) has become a symbol of the threat to biodiversity from climate change. Understanding polar bear evolutionary history may provide insights into apex carnivore responses and prospects during periods of extreme environmental perturbations. In recent years, genomic studies have examined bear speciation and population history, including evidence for ancient admixture between polar bears and brown bears (Ursus arctos). Here, we extend our earlier studies of a 130,000- to 115,000-y-old polar bear from the Svalbard Archipelago using a 10× coverage genome sequence and 10 new genomes of polar and brown bears from contemporary zones of overlap in northern Alaska. We demonstrate a dramatic decline in effective population size for this ancient polar bear’s lineage, followed by a modest increase just before its demise. A slightly higher genetic diversity in the ancient polar bear suggests a severe genetic erosion over a prolonged bottleneck in modern polar bears. Statistical fitting of data to alternative admixture graph scenarios favors at least one ancient introgression event from brown bears into the ancestor of polar bears, possibly dating back over 150,000 y. Gene flow was likely bidirectional, but allelic transfer from brown into polar bear is the strongest detected signal, which contrasts with other published work. These findings may have implications for our understanding of climate change impacts: Polar bears, a specialist Arctic lineage, may not only have undergone severe genetic bottlenecks but also been the recipient of generalist, boreal genetic variants from brown bears during critical phases of Northern Hemisphere glacial oscillations.