Publications

@article{magnusson_exposure_2024,

title = {Exposure of Colon-Derived Epithelial Monolayers to Fecal Luminal Factors from Patients with Colon Cancer and Ulcerative Colitis Results in Distinct Gene Expression Patterns},

author = {Maria K. Magnusson and Anna Bas Forsberg and Alexandra Verveda and Maria Sapnara and Julie Lorent and Otto Savolainen and Yvonne Wettergren and Hans Strid and Magnus Simrén and Lena Öhman},

url = {https://www.mdpi.com/1422-0067/25/18/9886},

doi = {10.3390/ijms25189886},

issn = {1422-0067},

year  = {2024},

date = {2024-09-13},

urldate = {2024-09-13},

journal = {Int. J. Mol. Sci.},

volume = {25},

number = {18},

pages = {9886},

abstract = {Microbiota and luminal components may affect epithelial integrity and thus participate in the pathophysiology of colon cancer (CC) and inflammatory bowel disease (IBD). Therefore, we aimed to determine the effects of fecal luminal factors derived from patients with CC and ulcerative colitis (UC) on the colonic epithelium using a standardized colon-derived two-dimensional epithelial monolayer. The complex primary human stem cell-derived intestinal epithelium model, termed RepliGut® Planar, was expanded and passaged in a two-dimensional culture which underwent stimulation for 48 h with fecal supernatants (FS) from CC patients (n = 6), UC patients with active disease (n = 6), and healthy subjects (HS) (n = 6). mRNA sequencing of monolayers was performed and cytokine secretion in the basolateral cell culture compartment was measured. The addition of fecal supernatants did not impair the integrity of the colon-derived epithelial monolayer. However, monolayers stimulated with fecal supernatants from CC patients and UC patients presented distinct gene expression patterns. Comparing UC vs. CC, 29 genes were downregulated and 33 genes were upregulated, for CC vs. HS, 17 genes were downregulated and five genes were upregulated, and for UC vs. HS, three genes were downregulated and one gene was upregulated. The addition of FS increased secretion of IL8 with no difference between the study groups. Fecal luminal factors from CC patients and UC patients induce distinct colonic epithelial gene expression patterns, potentially reflecting the disease pathophysiology. The culture of colonic epithelial monolayers with fecal supernatants derived from patients may facilitate the exploration of IBD- and CC-related intestinal microenvironmental and barrier interactions.},

note = {Publisher: Multidisciplinary Digital Publishing Institute},

keywords = {colon cancer, epithelial barrier, epithelial monolayers, inflammatory bowel disease, intestinal microenvironment},

pubstate = {published},

tppubtype = {article}

}

@article{sarma_design_2023,

title = {Design of 8-mer Peptides that Block Clostridioides difficile Toxin A in Intestinal Cells},

author = {Sudeep Sarma and Carly M. Catella and Ellyce T. San Pedro and Xingqing Xiao and Deniz Durmusoglu and Stefano Menegatti and Nathan Crook and Scott T. Magness and Carol K. Hall},

doi = {10.1101/2023.01.10.523493},

year  = {2023},

date = {2023-01-12},

urldate = {2023-01-12},

pages = {2023.01.10.523493},

abstract = {Clostridioides difficile ( C. diff .) is a bacterium that causes severe diarrhea and inflammation of the colon. The pathogenicity of C. diff . infection is derived from two major toxins, toxins A (TcdA) and B (TcdB). Peptide inhibitors that can be delivered to the gut to inactivate these toxins are an attractive therapeutic strategy. In this work, we present a new approach that combines a pep tide b inding d esign algorithm (PepBD), molecular-level simulations, rapid screening of candidate peptides for toxin binding, a primary human cell-based assay, and surface plasmon resonance (SPR) measurements to develop peptide inhibitors that block the glucosyltransferase activity of TcdA by targeting its glucosyltransferase domain (GTD). Using PepBD and explicit-solvent molecular dynamics simulations, we identified seven candidate peptides, SA1-SA7. These peptides were selected for specific TcdA GTD binding through a custom solid-phase peptide screening system, which eliminated the weaker inhibitors SA5-SA7. The efficacies of SA1-SA4 were then tested using a trans-epithelial electrical resistance (TEER) assay on monolayers of the human gut epithelial culture model. One peptide, SA1, was found to block TcdA toxicity in primary-derived human jejunum (small intestinal) and colon (large intestinal) epithelial cells. SA1 bound TcdA with a K D of 56.1 ± 29.8 nM as measured by surface plasmon resonance (SPR). 

SIGNIFICANCE STATEMENT: Infections by Clostridioides difficile , a bacterium that targets the large intestine (colon), impact a significant number of people worldwide. Bacterial colonization is mediated by two exotoxins: toxins A and B. Short peptides that can inhibit the biocatalytic activity of these toxins represent a promising strategy to prevent and treat C. diff . infection. We describe an approach that combines a Peptide B inding D esign (PepBD) algorithm, molecular-level simulations, a rapid screening assay to evaluate peptide:toxin binding, a primary human cell-based assay, and surface plasmon resonance (SPR) measurements to develop peptide inhibitors that block Toxin A in small intestinal and colon epithelial cells. Importantly, our designed peptide, SA1, bound toxin A with nanomolar affinity and blocked toxicity in colon cells.},

keywords = {Adverse events, epithelial barrier, In vitro model, inflammatory bowel disease, intestinal organoids, intestinal stem cells, microbiome},

pubstate = {published},

tppubtype = {article}

}

@article{bolster_impact_2022,

title = {Impact of selected novel plant bioactives on improvement of impaired gut barrier function using human primary cell intestinal epithelium:},

author = {Doug Bolster and Lee Chae and Jan-Willem van Klinken and Swati Kalgaonkar},

url = {http://www.isnff-jfb.com/index.php/JFB/article/view/301},

doi = {10.31665/JFB.2022.18324},

issn = {2637-8779},

year  = {2022},

date = {2022-12-30},

urldate = {2022-12-30},

journal = {Journal of Food Bioactives},

volume = {20},

abstract = {Gut barrier function is compromised in the obese state. The N-trans caffeoyltyramine (NCT) and N-trans feruloyltyramine (NFT), two naturally occurring bioactive compounds in hemp hulls, identified using in silico approaches, have the potential to improve gut barrier function and their effects were studied here in vitro. Proliferative human transverse colon epithelial cells were plated and co-cultured with tumor necrosis factor (TNF) along with NCT, NFT or NCT/NFT (2.2 ratio) post-differentiation, over a 48-hour period to induce inflammation and to observe the effects of NCT and NFT. A decrease in transepithelial electrical resistance (TEER) and increase in the intestinal permeability were observed with increased addition of TNF. Co-administration of NCT and NFT demonstrated a dose-dependent and statistically significant reversal of impaired TEER and intestinal permeability. NCT and NFT demonstrated a physiologically relevant reversal of impaired gut barrier function in the setting of inflammation via significant improvement in TEER and percent permeability.},

keywords = {Bioactives, Gut barrier function, Gut permeability, Hepatic nuclear factor 4α, In vitro model, inflammatory bowel disease, intestinal barrier, N-Trans-caffeoyltyramine, N-Trans-feruloyltyramine},

pubstate = {published},

tppubtype = {article}

}