Similar Datasets
Project description:Langerhans cells (LCs) are a unique population of phagocytes programmed within embryonic skin to maintain tissue and immunological homeostasis at the epidermal barrier site. Unique amongst tissue-resident macrophages, LCs play roles in skin innervation and repair, while also functioning as migrating professional antigen presenting cells, a capability classically assigned to dendritic cells (DC). We current lack insight into the molecular pathways that determine this dichotomy, when they are established, and whether precursors recruited to the adult skin niche access the same instructive signals laid down in utero. Tracking differentiation of monocyte-derived (m)LCs after destruction of embryo-derived cells in murine adult skin, revealed intrinsic intra-epidermal heterogeneity and selection of MDP-monocytes to by-pass gene programmes specifying a macrophage fate. Adopting a process unique to adult skin, subsequent extrinsic specification of EpCAM+ precursors via follicular Notch ligands, and aryl hydrocarbon receptor (Ahr) signalling, combined to determine commitment to resident mLCs. Using a unique human LC dataset, we demonstrated that embryo-derived (e)LCs in newborn human skin retained transcriptional evidence of their macrophage origin, which was superseded by a distinct DC-like immune modules following proliferation in infant skin. Thus, convergent differentiation of monocytes within adult skin exploits novel molecular pathways to replicate conditioning of eLC towards more immunogenic DC-like cells within post-natal skin.
2024-09-08 | GSE247878 | GEO
Project description:Langerhans cells (LCs) are a unique population of phagocytes programmed within embryonic skin to maintain tissue and immunological homeostasis at the epidermal barrier site. Unique amongst tissue-resident macrophages, LCs play roles in skin innervation and repair, while also functioning as migrating professional antigen presenting cells, a capability classically assigned to dendritic cells (DC). We current lack insight into the molecular pathways that determine this dichotomy, when they are established, and whether precursors recruited to the adult skin niche access the same instructive signals laid down in utero. Tracking differentiation of monocyte-derived (m)LCs after destruction of embryo-derived cells in murine adult skin, revealed intrinsic intra-epidermal heterogeneity and selection of MDP-monocytes to by-pass gene programmes specifying a macrophage fate. Adopting a process unique to adult skin, subsequent extrinsic specification of EpCAM+ precursors via follicular Notch ligands, and aryl hydrocarbon receptor (Ahr) signalling, combined to determine commitment to resident mLCs. Using a unique human LC dataset, we demonstrated that embryo-derived (e)LCs in newborn human skin retained transcriptional evidence of their macrophage origin, which was superseded by a distinct DC-like immune modules following proliferation in infant skin. Thus, convergent differentiation of monocytes within adult skin exploits novel molecular pathways to replicate conditioning of eLC towards more immunogenic DC-like cells within post-natal skin.
2024-09-08 | GSE247874 | GEO
Project description:Convergent evolution of MDP-monocyte differentiation in adult skin permits repair of the Langerhans cell network
| PRJNA1040853 | ENA
Project description:Langerhans cells (LCs) are distinct among phagocytes, functioning both as embryo-derived, tissue-resident macrophages in skin innervation and repair and as migrating professional antigen-presenting cells, a function classically assigned to dendritic cells (DCs). Here, we demonstrate that both intrinsic and extrinsic factors imprint this dual identity. Using ablation of embryo-derived LCs in the murine adult skin and tracking differentiation of incoming monocyte-derived replacements, we found intrinsic intraepidermal heterogeneity. We observed that ontogenically distinct monocytes give rise to LCs. Within the epidermis, Jagged-dependent activation of Notch signaling, likely within the hair follicle niche, provided an initial site of LC commitment before metabolic adaptation and survival of monocyte-derived LCs. In the human skin, embryo-derived LCs in newborns retained transcriptional evidence of their macrophage origin, but this was superseded by DC-like immune modules after postnatal expansion. Thus, adaptation to adult skin niches replicates conditioning of LC at birth, permitting repair of the embryo-derived LC network.
| S-EPMC7616733 | biostudies-literature
Project description:Convergent evolution of MDP-monocyte differentiation in adult skin permits repair of the Langerhans cell network [RNA-seq]
| PRJNA1040849 | ENA
Project description:Convergent evolution of MDP-monocyte differentiation in adult skin permits repair of the Langerhans cell network [scRNA-seq]
| PRJNA1040858 | ENA
Project description:Langerhans cells (LCs) maintain tissue and immunological homeostasis at the epidermal barrier site. They are unique among phagocytes in functioning both as embryo-derived, tissue-resident macrophages that influence skin innervation and repair, and as migrating professional antigen presenting cells, a capability classically assigned to dendritic cells (DC). Here we report the mechanisms that determine this dual identity. Using ablation of embryo-derived LCs in murine adult skin and tracked differentiation of incoming monocyte-derived replacements, we reveal intrinsic intra-epidermal heterogeneity. Macrophage-dendritic cell precursors are selected for survival in the skin environment, by-passing gene programs that specify a macrophage fate. We demonstrate that the hair follicle niche provides Notch signals that impose LC identity. In human skin, we show that embryo-derived (e)LCs in newborns retain transcriptional evidence of their macrophage origin, but this is superseded by distinct DC-like immune modules after expansion of the eLC network. Thus, cellular adaptation to the adult skin niche replicates conditioning of eLC, instructing DC-like programmes within macrophages
2025-04-03 | GSE251705 | GEO
Project description:Convergent evolution of monocyte differentiation in adult skin instructs Langerhans cell identity
| PRJNA1055091 | ENA
Project description:IntroductionThe endocannabinoid system (ECS), named after the chemical compounds found in the cannabis plant, is a regulatory network of neurotransmitters, receptors, and enzymes that plays crucial roles in skin health and disease. Endogenous ligands of the ECS, called endocannabinoids, have proven to be important regulators of immune responses. One of the most prevalent endocannabinoids, arachidonoylethanolamide (also known as anandamide), is known for its anti-inflammatory effects. Langerhans cells (LCs) are the sole antigen-presenting cells present in the human epidermis. They serve as the first line of defense against pathogens and are essential for the skin's specific immune responses and play a critical role in maintaining tissue homeostasis; however, little is known about the effect of endocannabinoids on these cells. Our research aimed to provide the connection between monocyte-derived Langerhans cells (moLCs) and the ECS, shedding light on their collaborative roles in immune homeostasis and inflammation.MethodsHuman monocytes were differentiated into moLCs using established protocols. Anandamide was applied during the differentiation process to test its effect on the viability, marker expression, and cytokine production of the cells, as well as in short term treatments for intracellular calcium measurement. TLR ligands applied after the differentiation protocol were used to activate moLCs. The impact of anandamide on the functionality of moLCs was further assessed using differential gene expression analysis of bulk RNA-Seq data, moLC-T cell cocultures, while ELISpot was employed to determine polarization of T cells activated in the aforementioned cocultures.ResultsAnandamide did not significantly affect the viability of moLCs up to 10 µM. When applied during the differentiation process it had only a negligible effect on CD207 expression, the prototypic marker of LCs; however, there was an observed reduction in CD1a expression by moLCs. Anandamide had no significant effects on the maturation status of moLCs, nor did it affect the maturation induced by TLR3 and TLR7/8 agonists. MoLCs differentiated in the presence of anandamide did however show decreased production of CXCL8, IL-6, IL-10 and IL-12 cytokines induced by TLR3 and TLR7/8 activation. Anandamide-treated moLCs showed an increased capability to activate naïve T cells; however, not to the level seen with combined TLR agonism. RNA sequencing analysis of moLCs differentiated with anandamide showed modest changes compared to control cells but did reveal an inhibitory effect on oxidative phosphorylation specifically in activated moLCs. Anandamide also promoted the polarization of naïve T cells towards a Th1 phenotype.DiscussionOur results show that anandamide has nuanced effects on the differentiation, maturation, cytokine secretion, metabolism and function of activated moLCs. Among these changes the decrease in CD1a expression on moLCs holds promise to selectively dampen inflammation induced by CD1a restricted T cells, which have been implicated as drivers of inflammation in common inflammatory skin conditions such as psoriasis, atopic dermatitis and contact dermatitis.
| S-EPMC11228147 | biostudies-literature
Project description:Angiogenesis, the growth of new blood vessels from pre-existing vessels, occurs during development, injury repair, and tumorigenesis to deliver oxygen, immune cells, and nutrients to tissues. Defects in angiogenesis occur in cardiovascular and inflammatory diseases, and chronic, non-healing wounds, yet treatment options are limited. Here, we provide a map of the early angiogenic niche by analyzing single-cell RNA sequencing of mouse skin wound healing. Our data implicate Langerhans cells (LCs), phagocytic, skin-resident immune cells, in driving angiogenesis during skin repair. Using lineage-driven reportersw, three-dimensional (3D) microscopy, and mouse genetics, we show that LCs are situated at the endothelial cell leading edge in mouse skin wounds and are necessary for angiogenesis during repair. These data provide additional future avenues for the control of angiogenesis to treat disease and chronic wounds and extend the function of LCs beyond their canonical role in antigen presentation and T cell immunity.
| S-EPMC10848275 | biostudies-literature