Biology subjects

Abdurahiman, S.

Publications and source records attributed to Abdurahiman, S..

5 recordsLinked to original sources

bioRxiv2026

UNRAVELLING A HIDDEN SUBTYPE: MULTIOMICS REVEAL PSORIASIS-LIKE SIGNATURE WITH SURGICAL RELEVANCE IN A SUBSET OF PERIANAL FISTULIZING CROHN'S DISEASE

Background and aimsPerianal fistulizing Crohns disease (pCD) affects 20% of patients with Crohns disease (CD) and severely impacts quality of life. Current therapies fail to provide sustained relief, and the molecular underpinnings of pCD remain poorly understood. This study aimed to elucidate the molecular landscape of perianal fistulas through multiomic profiling. MethodsPaired fistula-tract and adjacent rectal mucosal biopsies were collected from 63 patients (48 with pCD, 15 with cryptoglandular fistula [CPTGL]). Longitudinal sampling generated 101 unique molecular profiles, comprising of both RNA sequencing (RNA-seq) and 16S rRNA sequencing from both tissue sites, followed by integrative multiomics and gene network analyses. ResultsUnsupervised clustering revealed three patient clusters primarily defined by host gene expression, with minimal contribution from microbial profiles. Fistulae in clusters 1 and 2 showed strong immune activation and epithelial-mesenchymal transition (EMT). In contrast, cluster 3 fistulae displayed keratinization and metabolic reprogramming resembling psoriatic skin, together with reduced JAK-STAT signalling. Cluster 3 was enriched for patients classified as TOpClass:2a, who are more suitable for surgical repair (p = 0.02). Conversely, cluster 2, characterized by rectal keratinization and EMT in both fistula and rectum, showed the highest MRI inflammatory-mass score (p = 0.02) and a greater risk of subsequent ileostomy (Kaplan-Meier; p = 0.008). An independent RNAseq dataset validated the keratinization signature in a subset of pCD fistulae. ConclusionIntegrated multiomic analysis identified distinct molecular subtypes of pCD with surgical and therapeutic relevance. These findings refine the molecular understanding of pCD and support a precision medicine approach. What You Need to Know?O_ST_ABSBACKGROUND AND CONTEXTC_ST_ABSO_LIPerianal fistulas affect 1 in 5 Crohns disease patients and have a severe negative impact on the quality of life of the patients. C_LIO_LIMost advanced IBD therapies are not efficacious for perianal Crohns disease. C_LIO_LISurgical repair is not suitable for all patients. C_LI NEW FINDINGSO_LIThis study is the first to delineate molecularly defined patient subtypes in perianal fistulizing Crohns disease. It further characterizes a psoriasis-like keratinization program in a subset of fistulas. Finally, it identifies molecular features and histological indicators that may explain-and potentially help predict-favorable surgical outcomes in selected patients C_LI LIMITATIONSO_LIFunctional and mechanistic studies will be required to further dissect the drivers and dynamics of the epithelial remodeling identified. C_LI CLINICAL RESEARCH RELEVANCEO_LIRaises the possibility of refining of existing clinical stratification using molecular markers for improved therapeutic management and outcome. C_LI BASIC RESEARCH RELEVANCEO_LIProposes keratinization as an opposing molecular process to EMT within the perianal fistula tract. C_LIO_LIIdentifies robust gene signatures associated with EMT and keratinization in the fistula for further experimental and clinical studies. C_LI

immunology↗

bioRxiv2024

Unveiling the guardians: IL-26-expressing MAIT cells protect epithelial barrier function and are dysregulated in Crohn's disease

BACKGROUND & AIMSInflammatory bowel disease (IBD) is characterized by a dysregulated immune response against the hosts microbiome. Mucosal-associated invariant T (MAIT) cells recognize microbiota-derived riboflavin metabolites and play a crucial role in mucosal homeostasis. However, their specific role in IBD remains enigmatic. MAIT cells express IL-26, a novel IL-10 family cytokine with a controversial role in IBD. We investigated the functions of MAIT cells and IL-26 in IBD using a unique combination of state-of-the-art 3D human intestinal tissue models and clinical samples. METHODSWe analyzed MAIT cells from the peripheral blood and intestinal tissue of Crohns disease (CD) patients, using immunofluorescence staining and flow cytometry to describe the phenotype and IL-26 expression of MAIT cells. We used 3D iPSC-derived intestinal organoids as a complex in vitro model of human tissue and RNA sequencing and functional assays such as wound healing assay to study the role of IL-26 in mucosal homeostasis and inflammation. RESULTSWe observed a reduction of MAIT cells in the peripheral blood of CD patients compared to healthy donors (1.5 {+/-} 0.4%; 4.1 {+/-} 1.1%; p < .0065) and a significant decrease of MAIT cells in inflamed compared to non-inflamed ileum of CD patients (0.1 {+/-} 0.03%; 0.17 {+/-} 0.05%; p < .042). MAIT cells were found pathologically activated in inflamed tissue, exhibiting differences in CD8 and CD4 expression and dysregulation of IL-26 expression. Furthermore, we demonstrated a protective role of IL-26 in mucosal homeostasis and inflammation in the iPSC-derived organoid model. CONCLUSIONOur results show a crucial role for IL-26 and MAIT cells in the homeostasis of intestinal tissue and in the pathogenesis of IBD. These cells may therefore represent new therapeutic targets for CD patients.

immunology↗

bioRxiv2023

IL-1R signaling drives enteric glia-macrophage interaction in colorectal cancer progression

Enteric glial cells (EGCs) have been implicated in colorectal cancer (CRC) pathogenesis. However, their precise mechanisms of interaction with the CRC immune cell compartment and pro-tumorigenic role remain unclear. This study aimed to investigate the immunomodulatory effects of EGCs on tumor-associated macrophages (TAMs) and their involvement in CRC progression. Using EGC depletion and supplementation models, we assessed the impact of EGCs on the immunomodulation of orthotopic murine CRC. Furthermore, by making use of Bulk RNA-sequencing of CRC EGCs and single-cell sequencing of the tumor microenvironment, we identified the factors involved in the EGC-TAM crosstalk. Findings demonstrate that EGCs acquire a reactive and immunomodulatory phenotype in both murine CRC models and patients, influencing TAM differentiation. Mechanistically, secretion of IL-1 by tumor-infiltrating monocytes and macrophages triggers the phenotypic and functional switch of CRC EGCs via IL-1R. Consequently, tumor EGCs secrete IL-6, promoting the differentiation of monocytes into pro-tumorigenic SPP1+ TAMs. Importantly, the reactive tumor EGCs phenotype correlates with worse disease outcomes in preclinical models and CRC patients. Here we uncover a previously unexplored neuroimmune interaction between EGCs and TAMs within the colorectal tumor microenvironment, informing potential therapeutic strategies and enhancing our understanding of CRC progression. eTOC SummaryOur study unveils a novel neuroimmune interaction between enteric glia and TAMs in colon carcinoma. Monocyte/Macrophage-derived IL-1 activates enteric glia, leading to the differentiation of pro-tumorigenic SPP1+ TAMs via glial-derived IL-6. Blocking glial IL-1R-signaling reduces colonic tumor lesions, highlighting IL-1R as a potential therapeutic target.

cancer biology↗

bioRxiv2023

Intercellular interaction between FAP fibroblasts and CD150 inflammatory monocytes mediates fibro-stenosis in Crohn's disease

Crohns disease (CD) is marked by recurring intestinal inflammation and tissue injury, often resulting in fibro-stenosis and bowel obstruction, necessitating surgical intervention with high recurrence rates. To elucidate complex intercellular interactions leading to fibro-stenosis in CD, we analysed the transcriptome of cells isolated from the transmural ileum of CD patients, including a trio of lesions from each patient: non-affected, inflamed, and stenotic ileum samples, and compared them with samples from non-CD patients. Our computational analysis revealed that pro-fibrotic signals from a subset of monocyte-derived cells expressing CD150 induce a disease-specific fibroblast population, resulting in chronic inflammation and tissue fibrosis. The transcription factor TWIST1 was identified as a key modulator of fibroblast activation and extracellular matrix (ECM) production. Therapeutic inhibition of TWIST1 inhibits fibroblast activation, reducing ECM production and deposition. These findings suggest that the myeloid-stromal axis may offer a promising therapeutic target to prevent fibro-stenosis in CD.

immunology↗

bioRxiv2021

Enteric glial cells favour accumulation of anti-inflammatory macrophages during the resolution of muscularis inflammation

ObjectiveMonocyte-derived macrophages (M{varphi}s) are crucial regulators during muscularis inflammation. However, it is unclear which microenvironmental factors are responsible for monocyte recruitment and neurotrophic M{varphi} differentiation in this paradigm. Here, we investigate M{varphi} heterogeneity at different stages of muscularis inflammation and determine how environmental cues can attract and activate tissue protective M{varphi}s. DesignSingle cell RNA sequencing was performed on immune cells from the muscularis of wild-type and CCR2-/- mice at different timepoints after muscularis inflammation. CX3CR1GFP/+ and CX3CR1CreERT2 R26YFP mice were analyzed by flow cytometry and immunofluorescence. The transcriptome of enteric glial cells (EGCs) was investigated using PLPCreERT2 Rpl22HA mice. In addition, we assessed the effect of supernatant from neurosphere-derived EGCs on monocyte differentiation based on the expression of pro- and anti-inflammatory factors. ResultsMuscularis inflammation induced marked alterations in mononuclear phagocyte populations associated with a rapid infiltration of Ly6c+ monocytes that locally acquired unique transcriptional states. Trajectory inference analysis revealed two main pro-resolving M{varphi} subpopulations during the resolution of muscularis inflammation, i.e. Cd206+ MhcIIhi and Timp2+ MhcIIlo M{varphi}s, which were both derived from CCR2+ monocytes. Interestingly, we found that EGCs were able to sense damage to the muscularis to stimulate monocyte recruitment and differentiation towards pro-resolving M{varphi}s via CCL2 and CSF1, respectively. ConclusionOur study provides a comprehensive insight into pro-resolving M{varphi} differentiation and their regulators during muscularis inflammation. We deepened our understanding in the interaction between EGCs and M{varphi}s, thereby highlighting pro-resolving M{varphi} differentiation as a potential novel therapeutic strategy for the treatment of intestinal inflammation.

immunology↗