Project description:The most experiments about buccal pouch mucosal cells were investigated in mice and hamster. In these studies we have used porcine buccal pouch mucosal cells cultured primarily in vitro to investigate the expression profile of new molecular markers of mucosal wounding, vascularization and proliferation. In this study, we demonstrated the gene expression profile of long time primary cultured porcine buccal pouch mucosal cells.
Project description:UC pouchitis is a potential model of UC. We prospectively examined the pouch transcriptomes of UC and familial adenomatous polyposis (FAP) IPAA patients to unveil molecular mechanisms of UC pouchitis susceptibility. Methods: Total RNA was isolated using the AllPrep DNA/RNA Mini Kit (QIAGEN, Cat No. 8020). RNA quality was evaluated using Bioanalyzer (Agilent, Santa Clara, CA). All RNA samples displayed RNA Integrity Number (RIN) >7. RNAseq including cDNA library preparation was processed at the Genomics Core Facility of University of Chicago (https://fgf.uchicago.edu/). Total RNA in the amount of 100-500μg per sample was depleted of ribosomal RNA using the Ribo-Zero kit (Epicentre, Madison, WI). The directional (first strand) cDNA libraries were prepared following the guide of TruSeq Stranded Total RNA Sample Preparation kit. Results: Unlike FAP patients, UC subjects exhibited a large set of differentially expressed genes (DEGs) between pouch and pre-pouch mucosa as early as 4 months after pouch functionalization. Functional pathway analysis of DEGs in UC pouch revealed: (1) Gain of colon-associated gene expressions and loss of ileum associated gene expressions, (2) enhanced state of immune/inflammatory response, and (3) suppressed xenobiotic, lipid, and bile acid metabolic pathways. These changes were corroborated upon reanalysis of a published larger cross-sectional study of UC and FAP patients. Moreover, >70% of DEGs mapped to published IBD and normal colonic microarray datasets displayed directional changes consistent with active UC, but not Crohn's disease. Conclusions: UC patients exhibit a unique transcriptomic response to ileal pouch creation that can be observed well before disease. The transcriptome alterations provide insights into pouchitis
Project description:Total abdominal colectomy (TAC) with a staged ileal pouch-anal anastomosis (IPAA) is a common surgical treatment for ulcerative colitis (UC). However, a significant percentage of patients experience pouch failure, leading to considerable morbidity. This retrospective case-control study aimed to identify histopathological features of the TAC specimen associated with subsequent pouch failure and to investigate the underlying molecular mechanisms of this susceptibility using single-cell spatial transcriptomics.
Project description:Restorative proctocolectomy with ileal pouch-anal anastomosis is a surgical procedure in patients with ulcerative colitis refractory to medical therapies. Pouchitis, the most common complication, is inflammation of the pouch of unknown etiology. To define how the intestinal immune system is distinctly organized in response to inflammation and to develop mechanistic hypotheses of pouchitis, we analyzed tissues from patients with and without pouchitis and from patients with ulcerative colitis using single-cell RNA sequencing. We examined pouch lamina propria CD45+ hematopoietic cells from intestinal tissues of ulcerative colitis patients with (n=15) and without an ileal pouch-anal anastomosis (n=11). Further in silico meta-analysis was performed to generate transcriptional interaction networks and identify drug targets for patients with inflamed pouches. We identified a population of IL1B+ antimicrobial macrophages and FOXP3+/BATF+ T cells that are expanded in inflamed tissues, which we further validated in other single cell RNA-seq datasets from IBD patients. Cell type specific markers obtained from single-cell RNA-sequencing was used to infer representation from bulk RNA sequencing datasets, which further implicated antimicrobial macrophages expressing IL1B with S100A8/A9 calprotectin as being associated with inflammation, and Bacteroidiales and Clostridiales bacterial taxa. We found that non-responsiveness to anti-integrin biologic therapies in ulcerative colitis patients was associated with the signature of this antimicrobial macrophage population in a subset of patients. This study identified conserved and distinct features of intestinal inflammation between parts of the small and large intestine undergoing similar inflammation conditions. Specifically, we relate inflammation of the pouch, a surgically constructed organ, to other inflammatory contexts throughout the gastrointestinal tract.
Project description:The pathophysiology of Crohn’s-like disease of the pouch (CDP) that develops after restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC) is unknown. We examined mucosal cells from patients with and without CDP using single cell analyses.
Project description:<p>This study involved evaluation of the tissue associated microbiome of the ileal pouch following surgery for ulcerative colitis (UC) or familial adenomatous polyposis (FAP). Individuals were recruited, with biopsies taken from the ileal pouch and the pre-pouch ileum, microbial DNA was extracted and sequenced using 454 pyrosequencing. Total bacterial community structure and abundance were evaluated to determine which changes were characteristic of inflammatory phenotypes including pouchitis (inflammation of the ileal pouch) and a Crohn's disease-like phenotype.</p>
Project description:Mast cells (MCs) were implicated in tissue remodelling in hamster models of heart inflammatory diseases. Here we asked whether MCs promote inflammatory neovascularization in hamster cheek pouch (HCP) parasitized by Trypanosoma cruzi, the protozoan that causes Chagas disease. Intravital microscopy (IVM) performed 3 days after inoculation of Dm28c trypomastigote (GFP-TCTs) showed a subtle infiltration of rhodamine-labeled leukocytes. Interestingly, the baseline levels of FITC-dextran leakage (3 dpi) were consistently increased, raising the possibility that intracellular amastigotes may coopt the low-grade inflammation to facilitate the delivery of plasma-borne nutrients during the period in which host cells must metabolically sustain parasite division. Although proangiogenic indexes were only mildly stimulated at 3 dpi, we found a positive correlation with transcription of proinflammatory cytokines (pro-IL- and IFN-). Having established 3 dpi as a timepoint in which vascular remodeling was already measurable, we next compared the proteomic profiles of parasitized HCP with those of internal controls (PBS injected 3 days earlier in the contralateral pouch) we found 87 proteins upregulated, and 17 were downregulated in the parasitized HCP. Minor changes in protein expression were observed in response to PBS injection (2 upregulated and 12 downregulated proteins. Congruent with the increased density of MCs observed in parasitized HCP (histological analysis), the MC protease 1 (chymase) stood out as the most abundant sequence. Interestingly, toluidine blue staining appointed clusters of MCs degranulating at 3 dpi. Noteworthy, two plasma proteins (complement C3 and serum albumin) were also identified as major proteins, further suggesting that leaky capillaries irrigated the HCP at early stages (3 dpi) of infection . Detection of cytokines or classical proangiogenic factors was beyond the sensitivity of our methods.
Project description:To examine the mechanism underlying chemoprevention and changes in gene expression pattern induced by chlorophyllin and ellagic acid during 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis
Project description:A total proctocolectomy with ileal pouch-anal anastomosis (IPAA) is considered the surgery of choice for definitive management of familial adenomatous polyposis (FAP) and selected patients with ulcerative colitis (UC). However, this surgical treatment often associates with a long-term complication, pouchitis, which occurs mostly in UC patients. To better define the molecular background of pouchitis, the microarray-based survey was performed using pouch mucosal samples collected from 28 and 8 patients operated for UC and FAP, respectively. A number of 4771 genes was significantly differentiating uninflamed from inflamed mucosal samples, and their functional features were represented mostly by alerted metabolic and cell proliferation pathways. In contrast, functional analyses of aberrantly expressed probe sets between UC and FAP samples, irrespectively of mucosal inflammation status, revealed multiple pathways and terms which were linked to changes in immune response. Noteworthy, the comparison of uninflamed UC and FAP samples distinguished a set of 26 altered mRNAs including inflammation-related transcript encoding a Charcot-Leyden crystal (CLC) protein. The most discrete changes in gene expression profiles differentiating uninflamed UC and FAP mucosal samples were attributed to a Gene Ontology category innate immune response. Our study confirmed alterations of the immune responses as dominant in UC pouchitis which were earlier found in the studies using analyses of singular molecular elements. This observation may be important when managing IPAA patients. Each sample represents three biopsies taken from single patient, from the same areas of the lower part of the pouch mucosa (above the rectal cuff) during endoscopic examination. 28 patients underwent surgery for UC and 8 patients for FAP.