Similar Datasets
Project description:Demodex mites are obligate commensal parasites of hair follicles (HF) in mammals. Normally asymptomatic, inflammatory outgrowth of mites can accompany malnutrition, immune dysfunction and aging, but mechanisms restricting Demodex outgrowth and pathogenesis are not defined. Here, we show that control over mite HF colonization of mice requires ILC2s, IL-13, and its receptor IL-4Ra, but not IL-4 or the adaptive immune system. Epithelial HF-associated ILC2s elaborate IL-13 that attenuates HF and epithelial cell proliferation at anagen onset; in their absence, Demodex colonization leads to increased epithelial proliferation and replacement of gene programs for repair by aberrant inflammatory programs leading to loss of barrier function and premature HF exhaustion over time. Humans with rhinophymatous acne rosacea, a nasal inflammatory condition associated with a high burden of Demodex, had increased HF inflammatory cells with decreased type 2 cytokines, consistent with the inverse relationship seen in mice. Our studies uncover a critical role for skin ILC2s and IL-13, which comprise an immune checkpoint necessary to sustain cutaneous integrity and restrict pathologic infestation by colonizing HF mites.
2022-08-29 | GSE197982 | GEO
Project description:Demodex mites are obligate commensal parasites of hair follicles (HF) in mammals. Normally asymptomatic, inflammatory outgrowth of mites can accompany malnutrition, immune dysfunction and aging, but mechanisms restricting Demodex outgrowth and pathogenesis are not defined. Here, we show that control over mite HF colonization of mice requires ILC2s, IL-13, and its receptor IL-4Ra, but not IL-4 or the adaptive immune system. Epithelial HF-associated ILC2s elaborate IL-13 that attenuates HF and epithelial cell proliferation at anagen onset; in their absence, Demodex colonization leads to increased epithelial proliferation and replacement of gene programs for repair by aberrant inflammatory programs leading to loss of barrier function and premature HF exhaustion over time. Humans with rhinophymatous acne rosacea, a nasal inflammatory condition associated with a high burden of Demodex, had increased HF inflammatory cells with decreased type 2 cytokines, consistent with the inverse relationship seen in mice. Our studies uncover a critical role for skin ILC2s and IL-13, which comprise an immune checkpoint necessary to sustain cutaneous integrity and restrict pathologic infestation by colonizing HF mites.
2022-08-29 | GSE197981 | GEO
Project description:Demodex mites are obligate commensal parasites of hair follicles (HF) in mammals. Normally asymptomatic, inflammatory outgrowth of mites can accompany malnutrition, immune dysfunction and aging, but mechanisms restricting Demodex outgrowth and pathogenesis are not defined. Here, we show that control over mite HF colonization of mice requires ILC2s, IL-13, and its receptor IL-4Ra, but not IL-4 or the adaptive immune system. Epithelial HF-associated ILC2s elaborate IL-13 that attenuates HF and epithelial cell proliferation at anagen onset; in their absence, Demodex colonization leads to increased epithelial proliferation and replacement of gene programs for repair by aberrant inflammatory programs leading to loss of barrier function and premature HF exhaustion over time. Humans with rhinophymatous acne rosacea, a nasal inflammatory condition associated with a high burden of Demodex, had increased HF inflammatory cells with decreased type 2 cytokines, consistent with the inverse relationship seen in mice. Our studies uncover a critical role for skin ILC2s and IL-13, which comprise an immune checkpoint necessary to sustain cutaneous integrity and restrict pathologic infestation by colonizing HF mites.
2022-11-29 | GSE198657 | GEO
Project description:Observations in thyroid patients and experimental animals show that the skin is an important target for the thyroid hormones. We previously showed that deletion in mice of the thyroid hormone nuclear receptors TR?1 and TR? (the main thyroid hormone-binding isoforms) results in impaired epidermal proliferation, hair growth, and wound healing. Stem cells located at the bulges of the hair follicles are responsible for hair cycling and contribute to the regeneration of the new epidermis after wounding. Therefore a reduction in the number or function of the bulge stem cells could be responsible for this phenotype. Bulge cells show increased levels of epigenetic repressive marks, can retain bromodeoxyuridine labeling for a long time, and have colony-forming efficiency (CFE) in vitro. Here we demonstrate that mice lacking TRs do not have a decrease of the bulge stem cell population. Instead, they show an increase of label-retaining cells (LRCs) in the bulges and enhanced CFE in vitro. Reduced activation of stem cells leading to their accumulation in the bulges is indicated by a strongly reduced response to mobilization by 12-O-tetradecanolyphorbol-13-acetate. Altered function of the bulge stem cells is associated with aberrant activation of Smad signaling, leading to reduced nuclear accumulation of ?-catenin, which is crucial for stem cell proliferation and mobilization. LRCs of TR-deficient mice also show increased levels of epigenetic repressive marks. We conclude that thyroid hormone signaling is an important determinant of the mobilization of stem cells out of their niche in the hair bulge. These findings correlate with skin defects observed in mice and alterations found in human thyroid disorders.
| S-EPMC4454174 | biostudies-other
Project description:Tight immune defense against environment and a unique ability of self-repair are the hallmarks of epithelia. Here we show that innate immunity Toll like receptor 2 (TLR2) coordinates these key functions thereby promoting hair growth and tissue regeneration. TLR2 is enriched in hair follicle stem cells (HFSCs) and its levels change in hair cycle and skin disorders. The lack of TLR2 in HFSCs diminishes activation and proliferation of HFSCs markedly prolonging the resting phase of hair cycle. Transcriptome profiling of HFSCs revealed that TLR2 regulates main hair regeneration pathways. TLR2 deletion upregulates inhibitory BMP7 signaling, while the blockade by Noggin restores deficient HFSCs proliferation in the absence of TLR2. In injury model TLR2 is required for both, tissue and hair regeneration. While endothelial TLR2 drives wound revascularization and closure, HFSC TLR2 controls hair regrowth. Endogenous TLR2 ligand produced in hair follicles promotes hair regeneration and growth via HFSC TLR2. Together, HFSC TLR2 drives stem cell proliferation, hair cycle and regeneration.
2024-01-04 | GSE179300 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2015-11-08 | E-GEOD-62759 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2015-02-27 | E-GEOD-64814 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below.
2023-06-14 | GSE212674 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
2014-09-30 | E-GEOD-61506 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the SubSeries listed below.
2021-09-30 | GSE133648 | GEO