Langerhans cell histiocytosis (LCH) is a rare disorder characterized by the proliferation of dendritic cells resulting in local or systemic symptoms. The clinical symptoms of patients with Langerhans cell histiocytosis depend on the site and the degree of involvement. This article describes two case histories of unifocal bony Langerhans cell histiocytosis with mandibular involvement and further discusses the appropriate management of such via a review of the literature.
Dendritic Cells ; Histiocytosis, Langerhans-Cell ; Humans ; Mandible

Indeterminate dendritic cell tumor (IDCT) is a dendritic cell tumor that displays histologic features similar to those of Langerhans cells. The origin of the indeterminate cells may represent precursors of Langerhans cells or skin dendritic cells. IDCT is extremely rare, and tumor progression and predictive factors are not well known. Here, we report a case of a 61-year-old man who presented with a papule on his back and was finally diagnosed with IDCT based on histology and immunohistochemistry. The tumor recurred three months after surgical excision.
Dendritic Cells ; Humans ; Immunohistochemistry ; Langerhans Cells ; Middle Aged ; Recurrence ; Skin

BACKGROUND: These days, narrowband-UVB (NB-UVB) phototherapy is used worldwide for treating psoriasis. Some evidence allegedly suggests that, in contrast to broadband UVB therapy, near- erythemogenic doses are not required as starting doses for NB-UVB phototherapy to decrease the risk of burning. However, a recent study has proved that the near-erythemogenic dose to start NB-UVB phothotherapy was preferable to the far-erythemogenic dose method. OBJECTIVE: We compared the therapeutic effects between 70% MED (MED70%) and 50% MED (MED50%) methods in NB-UVB phototherapy of psoriasis. In addition, to elucidate the action mechanism of NB-UVB in psoriasis treatment, we also investigated the immunosuppresive effects of Langerhans cells, macrophages and chemokine/chemokine receptors. METHOD: We compared the near-erythemogenic NB-UVB protocol (initial 70% MED+delta10% increase at each visit, twice per week) with the far-erythemogenic protocol (initial 50% MED+delta10% increase at each visit, twice per week). We performed skin biopsies after 4 times of 1 MED, once of 4 MED and once of 1 MED, along with corresponding controls from the lesional and non-lesional sites. Immunohistochemistry was also performed with anti-CD1a, anti-CD11b, anti-MCP-1 and anti-CCR2 antibodies. RESULTS: The results of immunohistochemcial experiments were as follows; 1. NB-UVB irradiation decreased the number of CD1a+ Langerhans cells in the epidermis, but increased CD11b+ macrophages in the dermis. CD11b+ macrophages were increased more in the dermis in single high-dose irradiation than repeated small dose irradiations of equivalent total doses. 2. MCP-1 was expressed only in the entire epidermis of the psoriatic lesion, and was especially high in proliferating keratinocytes of basal and suprabasal layers. It was also expressed in the papillary dermis to a lesser extent. CCR2, a receptor for MCP-1, was also found to be expressed in a similar pattern to MCP-1. Single high-dose irradiation reduced MCP-1 and CCR2 to a moderate degree, especially in the basal layer, more than the repeated low-dose irradiation of an equivalent total dose. CONCLUSION: The near erythemogenic NB-UVB protocol (MED70%) showed an earlier resolution of the psoriatic lesions and a lower recurrent rate than the far-erythemogenic NB-UVB protocol. Higher NB-UVB reduced the number of CD1a+ Langerhans cells in the epidermis, and increased CD11b+ monocytes/macrophages in the dermis. A higher dose of NB-UVB downregulated CCR-2 and MCP-1 expression. The expression patterns of epidermal and dermal APCs and chemokines in this study indicate that NB-UVB in psoriasis treatment has immunosuppressive properties. For better NB-UVB protocols in psoriasis treatment, higher starting doses and incremental doses may be desirable.
Antibodies ; Biopsy ; Burns ; Chemokines* ; Dendritic Cells* ; Dermis ; Epidermis ; Immunohistochemistry ; Keratinocytes ; Langerhans Cells ; Macrophages ; Phototherapy* ; Psoriasis* ; Skin

BACKGROUND: Dendritic cells (DCs) play an important role in immune reactions. This study was designed to identify the distribution patterns of DCs and regulatory T-cells (Tregs) in cutaneous lymphomas. METHODS: Immunohistochemistry was used to determine langerin expression on Langerhans cells, CD11b on inflammatory DCs, CD209 and CD11c on dermal DCs, CD303 on plasmacytic DCs, and Foxp3 on Tregs in 81 cases of cutaneous lymphomas. RESULTS: Various DCs and Tregs were identified in most cutaneous lymphomas. Plasmacytic DCs, inflammatory DCs and Tregs were identified mainly in tumor areas, whereas dermal DCs were distributed both in the tumor and stromal areas. Among DCs, dermal DCs were most prominently identified in the cutaneous lymphomas not only in the tumor area but also in the stroma. The intense stromal infiltration of dermal DCs was consistent finding in T-cell lymphomas. Diffuse large B-cell lymphoma (DLBCL), not otherwise specified also showed intense stromal infiltration of dermal DCs, but stromal infiltration in DLBCL, leg type was relatively scant. CONCLUSIONS: The results suggest that all types of DCs and Tregs are involved in cutaneous lymphoma tumor immunity. Among them dermal DCs may play a dominant role.
Dendritic Cells ; Immunohistochemistry ; Langerhans Cells ; Leg ; Lymphoma ; Lymphoma, B-Cell ; Lymphoma, T-Cell ; T-Lymphocytes, Regulatory

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Dendritic Cells

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Dendritic Cells*

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Dendritic Cells*

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Dendritic Cells*

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Dendritic Cells

In normal hurnan dermis, factor XIIIa positive dermal dendrocyte are located in the papillary areas closely associated with blood vessels and the upper reticular dem These cells represent a specific type of bone marrow derived dermal cells, distinct from Langerhans cells having some features in common with rnonocyte/macrophage lineage and with potential antier presenting activity. Although the significance of these cells has not yet been fully established, it been suggested that they play a major role in skin immune iesponses, in collagen synsthesis regultic and in wound repair. We report a case of acaqired fibrokeratoma which is studiec conventional histopathology and immunohistochemistry. Histopathologic findings of this case showed ovascular proliferation and the increased presence of fibroblast like cells as a common fe;ture of these benign tumors. Immunohistochemical staining with anti factor XIIIa antibody deiaoi strates increased numbera of positive dendritic cells in the upper dermis. There finding supports the fat that some fibroblagt like cells in the upper dermis of acquireid fibrokeratoma may be factor XIIIa positive dermal dendritic cells.
Blood Vessels ; Bone Marrow ; Collagen ; Dendritic Cells ; Dermis ; Factor XIIIa* ; Fibroblasts ; Immunohistochemistry ; Langerhans Cells ; Skin ; Wounds and Injuries