One component of the skin defense system is the epidermis‐resident Langerhans cell (LC). Filamentous fungi from genera such as Trichophyton, Microsporum and Epidermophyton are common organisms associated with tineas. Layers and cell types of the epidermis and dermis. Lesional dendritic cells in patients with chronic atopic dermatitis and psoriasis exhibit parallel ability to activate T‐cell subsets, Immunocompetent cells in psoriasis. LCs migrate from the skin to the draining lymph nodes during steady state18 and their rate of migration is increased during inflammation.19 LCs also play a role in the maintenance of tolerance in normal skin by inducing the activation and proliferation of skin‐resident T regulatory cells.20 Here, we review the contribution of LCs to immunity and pathogenesis in infectious and inflammatory disease, and in cancer and wound healing (summarized in Figure 1). Gram‐positive bacteria, such as Staphylococcus and Micrococcus sp., not only represent majority of the commensal microorganisms that colonize the skin of healthy individuals, but also can be virulent following colonization of wounded skin.38 The dry nature of the skin does not generally support the growth of gram‐negative bacteria except for the occasional Acinetobacter sp. After a century of question about their purpose, it is now clear that they have a vital immunologic function. The Innate Immune Cell Profile of the Cornea Predicts the Onset of Ocular Surface Inflammatory Disorders. reported that LC scavenging can facilitate carcinogenesis in the DMBA/TPA model of SCC in mice.110 LCs did efficiently metabolize the toxin DMBA in the skin but the detoxification end products included an oncogenic intermediate, which was transferred to adjacent keratinocytes, causing HRAS mutations leading to SCC. Langerhans cells protect from allergic contact dermatitis in mice by tolerizing CD8, Dynamics and function of Langerhans cells, Functional redundancy of Langerhans cells and langerin, Epidermal Langerhans cell‐deficient mice develop enhanced contact hypersensitivity, Specific immunologic tolerance to dinitrofluorobenzene following topical application of dinitrothiocyanobenzene: modulation by suppressor T cells. Langerhans cell histiocytosis is a disorder in which excess immune system cells called Langerhans cells build up in the body. Langerhans Cells (LC) are dendritic cell (DC) that resides in the epidermis of skin. Dead cells are shed continuously from the epidermis as new ones take their place. New cells are made in the lower layers of the epidermis. Skin is the largest organ in the body and the most exposed to the environment. They specialize in antigen presentation and belong to the skin immune system (SIS). They specialize in antigen presentation and belong to the skin immune system (SIS). LCs are the first immune cells that fungi encounter once they have penetrated the integument, and human LC recognition of fungi is by binding of the surface langerin to the mannan and beta‐glucan structures found on the fungal cell wall.52 LCs increase in number in Trichophyton‐infected human epidermis,53 and are able to induce cellular immunity to trichophytin in vitro.54, The most common fungal species to cause yeast mucocutaneous infections is the dimorphic Candida albicans. For example, alterations in cytokine secretions by keratinocytes may be used to modulate variations in LC number and antigen expression in human oral mucosal diseases,131 as has been shown on gingival LCs in organotypic culture. The development of therapies that modulate LCs directly, or that target downstream effects of LCs, may provide treatments for patients suffering from inflammatory diseases or skin cancers. Impaired Langerhans cell migration in psoriasis, Impaired Langerhans cell migration in psoriasis is due to an altered keratinocyte phenotype induced by interleukin‐17, Langerin(neg) conventional dendritic cells produce IL‐23 to drive psoriatic plaque formation in mice, IL‐23 from Langerhans cells is required for the development of imiquimod‐induced psoriasis‐like dermatitis by induction of IL‐17A‐producing γδ T cells, Monocyte‐derived inflammatory Langerhans cells and dermal dendritic cells mediate psoriasis‐like inflammation, Dynamics and transcriptomics of skin dendritic cells and macrophages in an imiquimod‐induced, biphasic mouse model of psoriasis, Specific roles for dendritic cell subsets during initiation and progression of psoriasis, Disruption of the stratum corneum allows potent epicutaneous immunization with protein antigens resulting in a dominant systemic Th2 response, IL‐22‐producing “T22” T cells account for upregulated IL‐22 in atopic dermatitis despite reduced IL‐17‐producing TH17 T cells, Langerhans cells are critical in epicutaneous sensitization with protein antigen via thymic stromal lymphopoietin receptor signaling, Langerhans cells are critical in the development of atopic dermatitis‐like inflammation and symptoms in mice, The transcription factor STAT5 is critical in dendritic cells for the development of TH2 but not TH1 responses, Distinct behavior of human Langerhans cells and inflammatory dendritic epidermal cells at tight junctions in patients with atopic dermatitis, Cutaneous barrier perturbation stimulates cytokine production in the epidermis of mice, A model system using tape stripping for characterization of Langerhans cell‐precursors, The presence of IgE molecules on epidermal Langerhans cells in patients with atopic dermatitis, Unraveling the mission of FcϵRI on antigen‐presenting cells, Regulatory T cells in atopic dermatitis: epidermal dendritic cell clusters may contribute to their local expansion, Targeting of epidermal Langerhans cells with antigenic proteins: attempts to harness their properties for immunotherapy, Langerhans cells as targets for immunotherapy against skin cancer, Variations in the distribution, frequency, and phenotype of Langerhans cells during the evolution of malignant melanoma of the skin, Quantitative alterations in cutaneous Langerhans cells during the evolution of malignant melanoma of the skin, Human Langerhans cells are immature in melanoma sentinel lymph nodes, Investigating the role of Langerhans cells in primary cutaneous melanoma, Occurrence of Langerhans cells and expression of class II antigens on keratinocytes in malignant and benign epithelial tumors of the skin: an immunohistopathologic study with monoclonal antibodies, Langerhans’ cells and T cells in human skin tumours: an immunohistological study, Quantitative assessment of Langerhans cells in actinic keratosis, Bowen's disease, keratoacanthoma, squamous cell carcinoma and basal cell carcinoma, Quantitative study of Langerhans cells in basal cell carcinoma with higher or lower potential of local aggressiveness, Number of Langerhans cells is decreased in premalignant keratosis and skin cancers, Langerhans cells and NK cells cooperate in the inhibition of chemical skin carcinogenesis, Multifaceted contributions of epidermal Langerhans cells to cutaneous carcinogenesis, Langerhans cells facilitate epithelial DNA damage and squamous cell carcinoma, Langerhans cells from human cutaneous squamous cell carcinoma induce strong type 1 immunity, Prevention of UV radiation–induced immunosuppression by IL‐12 is dependent on DNA repair, Langerhans cells are required for UVR‐induced immunosuppression, Progressor but not regressor skin tumours inhibit Langerhans’ cell migration from epidermis to local lymph nodes, Repopulation of Langerhans cells during wound healing in an experimental human skin/SCID mouse model, Expression of natural antimicrobial peptide beta‐defensin‐2 and Langerhans cell accumulation in epidermis from human non‐healing leg ulcers, Increased number of Langerhans cells in the epidermis of diabetic foot ulcers correlates with healing outcome, Effect of zinc supplementation on epidermal Langerhans’ cells of elderly patients with decubital ulcers, Keratinocyte‐derived monocyte chemoattractant protein 1 (MCP‐1): analysis in a transgenic model demonstrates MCP‐1 can recruit dendritic and Langerhans cells to skin, Epidermal proliferation is not impaired in chronic venous ulcers, Hypertrophic scar formation is associated with an increased number of epidermal Langerhans cells, Activated keratinocytes in the epidermis of hypertrophic scars, Keratinocyte‐derived growth factors play a role in the formation of hypertrophic scars, Site‐specific immunophenotyping of keloid disease demonstrates immune upregulation and the presence of lymphoid aggregates, Partial epithelial‐mesenchymal transition in keloid scars: regulation of keloid keratinocyte gene expression by transforming growth factor‐β1, Effects of topical corticosteroid therapy on Langerhans cell antigen presenting function in human skin, Pimecrolimus leads to an apoptosis‐induced depletion of T cells but not Langerhans cells in patients with atopic dermatitis, Imiquimod, a topical immune response modifier, induces migration of Langerhans cells, Tacrolimus reverses UVB irradiation‐induced epidermal Langerhans cell reduction by inhibiting TNF‐α secretion in keratinocytes via regulation of NF‐κB/p65, Modulation of Langerhans cell surface antigen expression by recombinant cytokines, A human anti‐CD1a monoclonal antibody for targeted immunotherapy in Langerhans cell histiocytosis and hematologic malignancies, Langerhans cell‐like dendritic cells stimulated with an adjuvant direct the development of Th1 and Th2 cells. 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