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Elmets, C. A.

Publications and source records attributed to Elmets, C. A..

5 recordsLinked to original sources

Metabolic Repression of Autophagy Drives Inflammation, Pain, and Malodor in Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a debilitating and underdiagnosed inflammatory skin disease with limited therapeutic options due to an incomplete understanding of its molecular and immunopathogenic basis. Using an integrated multi-omics approach, we delineate convergent pathways linking dysregulated autophagy, malodour, and pain in HS. Lesional tissues exhibited sustained autophagy repression, marked by increased expression and activation of mTOR and ZKSCAN3, reduced levels of autolysosome-promoting metabolites {beta}-hydroxybutyrate and nicotinamide riboside, and accumulation of fructose-1,6-bisphosphate, a negative regulator of AMPK. Transcriptomic analyses identified cadaverine derivatives as key metabolic drivers of keratinocyte reprogramming, inducing gene networks associated with hyperproliferation, inflammation, fibrosis, nociception, and the characteristic carrion-like odour of HS. Concordantly, ATAC-seq revealed increased chromatin accessibility at loci encoding TRP channels and histamine receptors, consistent with heightened nociceptive signalling. Multi-layered proteomics, phospho-proteomics, kinomics, and spatial proteomics analyses, validated by high-resolution confocal imaging, demonstrated elevated mTOR (Ser2448), ZKSCAN3, and P62, alongside reduced LAMP1, across keratinocytes and immune cell populations including CD4 T cells, CD56 NK cells, and CD68 macrophages. Inhibition of mTOR normalized transcriptional programs and cytokine production linked to NLRP3 inflammasome, restoring tissue homeostasis. Collectively, these findings identify a metabolically reinforced mTOR-ZKSCAN3 axis in autophagy dysregulation and cadaverine-driven epithelial reprogramming as central mechanisms sustaining inflammation, pain, and fibrosis in HS. HighlightsO_LIWe identified BCAAs, BHB, NR, and FBP as key metabolites linked to mTOR activation and autophagy dysregulation in HS. C_LIO_LIPolyamines like cadaverine and putrescine, their acetylated derivatives, LPCs, and endocannabinoid dysregulation likely drive malodor and pain in HS. C_LIO_LICadaverine treatment of Ker-CT cells induces HS-associated gene signatures of inflammation, fibrosis, and pain. C_LIO_LIIdentification of an HS macrophage subpopulation expressing ZKSCAN3 with activated mTOR and impaired autophagy. C_LI

immunology↗

Modeling epithelial homeostasis and perturbation in three-dimensional human esophageal organoids

BackgroundEsophageal organoids from a variety of pathologies including cancer are grown in Advanced Dulbeccos Modified Eagle Medium-Nutrient Mixture F12 (hereafter ADF). However, the currently available ADF-based formulations are suboptimal for normal human esophageal organoids, limiting the ability to compare normal esophageal organoids with those representing a given disease state. MethodsWe have utilized immortalized normal human esophageal epithelial cell (keratinocyte) lines EPC1 and EPC2 and endoscopic normal esophageal biopsies to generate three-dimensional (3D) organoids. To optimize ADF-based medium, we evaluated the requirement of exogenous epidermal growth factor (EGF) and inhibition of transforming growth factor-(TGF)-{beta} receptor-mediated signaling, both key regulators of proliferation of human esophageal keratinocytes. We have modeled human esophageal epithelial pathology by stimulating esophageal 3D organoids with interleukin (IL)-13, an inflammatory cytokine, or UAB30, a novel pharmacological activator of retinoic acid signaling. ResultsThe formation of normal human esophageal 3D organoids was limited by excessive EGF and intrinsic TGF{beta} receptor-mediated signaling. In optimized HOME0, normal human esophageal organoid formation was improved, whereas IL-13 and UAB30 induced epithelial changes reminiscent of basal cell hyperplasia, a common histopathologic feature in broad esophageal disease conditions including eosinophilic esophagitis. Conclusions: HOME0 allows modeling of the homeostatic differentiation gradient and perturbation of the human esophageal epithelium while permitting a comparison of organoids from mice and other organs grown in ADF-based media.

cell biology↗

NK and NKT cells in the pathogenesis of Hidradenitis suppurativa: Novel therapeutic strategy through targeting of CD2

Hidradenitis suppurativa (HS) is a chronic debilitating inflammatory skin disease with poorly understood pathogenesis. Single-cell RNAseq analysis of HS lesional and healthy individual skins revealed that NKT and NK cell populations were greatly expanded in HS, and they expressed elevated CD2, an activation receptor. Immunohistochemistry analyses confirmed significantly expanded numbers of CD2+ cells distributed throughout HS lesional tissue, and many co-expressed the NK marker, CD56. While CD4+ T cells were expanded in HS, CD8 T cells were rare. CD20+ B cells in HS were localized within tertiary follicle like structures. Immunofluorescence microscopy showed that NK cells (CD2+CD56dim) expressing perforin, granzymes A and B were enriched within the hyperplastic follicular epidermis and tunnels of HS and juxtaposed with apoptotic cells. In contrast, NKT cells (CD2+CD3+CD56bright) primarily expressed granzyme A and were associated with -SMA expressing fibroblasts within the fibrotic regions of the hypodermis. Keratinocytes and fibroblasts expressed high levels of CD58 (CD2 ligand) and they interacted with CD2 expressing NKT and NK cells. The NKT/NK maturation and activating cytokines, IL-12, IL-15 and IL-18, were significantly elevated in HS. Inhibition of cognate CD2-CD58 interaction with blocking anti-CD2 mAb in HS skin organotypic cultures resulted in a profound reduction of the inflammatory gene signature and secretion of inflammatory cytokines and chemokines in the culture supernate. In summary, we show that a cellular network of heterogenous NKT and NK cell populations drives inflammation, tunnel formation and fibrosis in the pathogenesis of HS. Furthermore, CD2 blockade is a viable immunotherapeutic approach for the management of HS.

immunology↗

Dysregulated Protein Translation Control in Hidradenitis Suppurativa: Implication for Lesion-associated Squamous Cell Carcinoma Development

Hidradenitis Suppurativa (HS) is a proinflammatory painful skin disorder. This chronic disease is often associated with aggressive squamous cell carcinoma (SCC). The molecular pathogenesis of this disease progression remains undefined. The translation initiation factor eIF4E/4G/4A1 complex is overexpressed in a variety of human malignancies. In this study, we found that the expression of eIF4E/4G/4A1 as well as phosphorylated eIF4E were upregulated in HS skin. In the global transcription profiles derived from two public database, we were able to enrich 734 eIF4F-related genes. GSEA pathway enrichment analysis further demonstrated that RAS/MEK/ERK oncogene signaling pathway associated with inflammation signaling were significantly activated in HS lesion. The increase expression of eIF4 protein components was associated with enhanced eIF4E translation targets Cyclin D1 and c-Myc. Confocal fluorescence microscopy analysis further revealed that Cyclin D1 and c-Myc specifically co-localized in nuclei of certain cells in HS epithelium. We also found that many of the PCNA positive hyperproliferative cells were also positive for c-Myc expression. These data demonstrate that 5-cap{square}dependent translation is a potential pathway underlying the SCC pathogenesis in chronic HS lesions. Furthermore, being a druggable target, inhibition of eIF4F may block lesion-associated lethal SCCs in HS patients.

cancer biology↗

Ex Vivo Culture Models of Hidradenitis Suppurativa for defining molecular pathogenesis and treatment efficacy of novel drugs

Hidradenitis suppurativa (HS) is a complex inflammatory and debilitating skin disease for which no effective treatment is available. This is partly because of the unavailability of suitable human or animal models with which exact pathobiology of the disease can be defined. Here, we describe the development of air-liquid (A-L) interface, liquid-liquid/liquid-submersion (L-S) and bioreactor (Bio) ex vivo skin culture models. All three ex vivo platforms were effective for culturing skin samples up to day-14, with the tissue architecture and integrity remaining intact for at least 3 days for healthy skin while for 14 days for HS skin. Up to day-3, no significant differences were observed in % early apoptotic cells among all three platforms. However, an increase was observed in late apoptotic/necrotic cells in HS skin at day-3 in A-L and Bio culture of HS skin. These cultures efficiently support the growth of various cells populations, including keratinocytes and immune cells. Profiling of the inflammatory genes using HS skin from these ex vivo cultures showed dynamic expression changes at day-3 and day-14. All of these cultures are necessary to represent the inflammatory gene status of HS skin at day-0 suggesting that not all gene clusters are identically altered in each culture method. Similarly, cytokine/chemokine profiling of the supernatant from vehicle- and drug-treated ex vivo HS cultures again showed better prediction of drug efficacy against HS. Overall, development of these three systems collectively provide a powerful tool to uncover the pathobiology of HS progression and screen various drugs against HS.

pathology↗