Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06126 (CD1a)
 2,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Congenital self-healing histiocytosis (CSHH) is a rare primary histiocytic skin disorder. Only a few cases have been studied by ultrastructure and immunohistochemistry. Here we report a new case that was investigated using an electron microscope and a panel of monoclonal (MCA) and polyclonal (PCA) antibodies. CSHH cells were found to bear the immunohistochemical phenotype of normal epidermal Langerhans cells (LC) and histiocytosis X (HX) cells (CD1a/c+, CD1b-, CD4+/-, human leukocyte antigen [HLA]-DR/DQ+, S-100+). However, an electron microscope showed a paucity of Birbeck granule (BG)-containing cells. This contrasted with their immunophenotype. This finding, along with other ultrastructural characteristics of CSHH cells, suggests that histologic differences exist between CSHH and HX. However, because no absolute histologic criterion is known that allows unequivocally the differential diagnosis between the two diseases, this distinction currently has to rely on clinical criteria, mainly the regressive course observed within a few months in CSHH. The precise nosologic position of CSHH among other histiocytic syndromes remains unsettled.
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PMID:Congenital self-healing histiocytosis (Hashimoto-Pritzker). An ultrastructural and immunohistochemical study. 327 80

Opioid peptides are synthesized in neurons, endocrine cells, monocytes/macrophages and B and T lymphocytes. They interact with opioid receptors located on immune cells and nociceptive nerve terminals. Because opioid peptides might be of importance in inflammatory skin diseases, for example psoriasis, sections of skin from psoriatic patients were immunohistochemically stained with antisera against methionine and leucine enkephalin, CD68 (KP1, PG-M1), calprotectin (M747), M130 (Ber-MAC3), CD1a and CD3. Enkephalin-like activity was detected selectively in dermal CD68-positive macrophages/monocytes. The activity showed no association with the activation markers M747 and Ber-MAC3. There was a statistically significant increase in enkephalin-positive cells in involved psoriatic skin compared with uninvolved and normal skin. These results were confirmed by radioimmunoassay which showed elevated levels in extracts from involved psoriatic skin compared with uninvolved skin (81%) and normal skin (204%). Furthermore, preproenkephalin mRNA of an expected size was detected in involved psoriatic skin. If the increased levels of enkephalins present in monocytes/macrophages in psoriatic skin lesions reach the threshold for biological activity, they may play a role in the regulation of the inflammatory processes seen in this skin disease.
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PMID:Enkephalin-like immunoreactivity in human skin is found selectively in a fraction of CD68-positive dermal cells: increase in enkephalin-positive cells in lesional psoriasis. 916 36

Papular xanthoma (PX) is a very rare skin disorder. We describe a typical case of PX in a 13-month-old Chinese boy who presented with numerous yellow-red papulonodules, 2-8 mm in diameter, mainly on the face, both upper extremities, and abdomen of 10 months duration. Histologic studies showed a diffuse monomorphous infiltrate of foamy cells in the upper dermis. The foamy cells stained positively with oil red O and CD68. The periodic acid Schiff (PAS) stain, S-100 protein, CD1a, CD56, lysozyme, alpha1-antitrypsin, and factor XIIIa were all negative in the foamy cells. The electron microscopic (EM) studies revealed the morphologic features of macrophages with electron-dense, membrane-limited lipid vacuoles in the cytoplasm. After 14 months, neither spontaneous regression nor anetoderma-like scars were noted. Our immunohistochemical and ultrastructural studies support the notion that the origin of the foamy cells is the macrophage rather than the factor XIIIa (+) dermal dendrocyte. There was no associated or underlying disease in this case. We suggest the term primary PX for cases such as this one.
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PMID:Primary papular xanthoma of children: a clinicopathologic, immunohistopathologic and ultrastructural study. 941 17

We describe a case of granulomatous mycosis fungoides, tumor stage, mimicking sarcoidosis in an 82-year-old man with a 2-year history of skin disease. The final diagnosis was established after one of seven biopsy specimens showed a nongranulomatous histologic picture of patch-stage mycosis fungoides. Monoclonality was proven for the lymphocytic population by T-cell-receptor rearrangement studies. The unusually extensive granulomatous inflammation with huge giant cells surrounded by CD1a-positive cells in the other six biopsy specimens was suggestive of the histopathology of granulomatous slack skin, another rare granulomatous cutaneous T-cell lymphoma. Because both a clinical and histologic overlap between granulomatous mycosis fungoides and granulomatous slack skin have been reported in the literature, we conclude that they may belong to the spectrum of a single disease.
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PMID:Granulomatous mycosis fungoides: report of a case with some histopathologic features of granulomatous slack skin. 1021 76

We evaluated the incidence, morphology, and immunophenotype of intraepidermal collections of mononuclear cells (ICMC) in a large number of inflammatory dermatosis and cutaneous lymphomas. ICMC appeared as small to large aggregates of cells, showing a morphology variable from monocytes to obvious dendritic cells, admixed with rare lymphocytes. ICMC were recognized in the epidermis or within hair follicle epithelium, and were either loosely or compactly arranged. ICMC were identified in 124 of 1,248 skin biopsies (9.9%) of inflammatory or lymphoid infiltrates, and were particularly frequent in spongiotic (43.4%) and in lichenoid dermatitis (10%), whereas they were rarely found in nonspecific superficial dermatitis (3.8%) and in psoriasis (4.7%). ICMC were also frequent in cutaneous T-cell lymphoma (13.3%), where they mimicked Pautrier abscesses. The ICMC forming cells showed a unique phenotype: the majority of them expressed CD1a and S-100, and lacked CD14, similar to mature Langerhans cells, but they were also strongly labeled by anti-CD11b, anti-CD36, and anti-CD68. Moreover, a subpopulation of them expressed CD83, an antigen that is usually absent on Langerhans cells. The occurrence of ICMC is a rather frequent, although hitherto poorly studied, phenomenon, occurring in several dermatosis, but particularly frequent in spongiosis-associated skin reactions. The cells within ICMC are represented by dendritic cells and dendritic cell precursors, whose phenotype indicates their derivation from circulating monocytes and differentiation into mature Langerhans cells.
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PMID:Nonlymphoid intraepidermal mononuclear cell collections (pseudo-Pautrier abscesses): a morphologic and immunophenotypical characterization. 1069 8

A 13-year-old girl developed a non-pruritic pityriasis rosea-like rash, which did not respond to topical corticosteroids or UV therapy but persisted for 2 years. The lymphohistiocytic infiltrate in the upper dermis showed mononuclear cells immunoreactive with S100, CD68, factor XIIIa and CD1a. Electron microscopic evaluation of these cells demonstrated lamellated dense bodies but no Birbeck granules, lipid vacuoles or cholesterol crystals. Two diagnoses were made: a primarily clinical diagnosis of generalized eruptive histiocytosis and a more cell-biology-based diagnosis of an indeterminate cell histiocytosis. Three years later, the lesions are showing spontaneous resolution, with loss of erythema and flattening. Our patient's indeterminate cells fulfil Rowden's classical definition (dendritically shaped epidermal non-keratinocytes without identifying cytoplasmic features), as well as Zelger's newer definition (cells with features of both macrophages and dendritic cells). A Christmas tree pattern has not been previously described in indeterminate cell histiocytosis. Development of indeterminate cell histiocytosis in the lesions of a healing pityriasis rosea might explain the unusual distribution pattern. The development of a skin disorder at the site of an unrelated, already healed skin disease is known as an isotopic response. Key
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PMID:Long-lasting "christmas tree rash" in an adolescent: isotopic response of indeterminate cell histiocytosis in pityriasis rosea? 1236 Nov 35

Exclusion of cutaneous T-cell lymphoma (CTCL) by another dermatosis has not been reported. The mechanism for the epidermotropism of helper T lymphocytes in this indolent malignancy is not known. Although there is evidence that Langerhans cells (LC) play a role in the epidermotropism of lymphocytes in CTCL, clinical or in vivo support is lacking. We describe a patient with CTCL who developed herpes zoster involving the left T8 dermatome. When his CTCL became widespread after the herpes zoster healed, the previously affected areas of herpes zoster and their periphery were clinically free of lymphoma. Immunohistochemical analysis of a clinically uninvolved patch revealed absence of CD1a(+) cells in the epidermis, consistent with loss of LC in the areas spared by CTCL. There was no loss of LC in areas affected by CTCL. This is an unusual inhibition of CTCL by a prior viral infection. The loss of LC in the clinically spared skin suggests a role for LC in the epidermotropism of lymphocytes in CTCL.
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PMID:Cutaneous T-cell lymphoma sparing resolving dermatomal herpes zoster lesions: an unusual phenomenon and implications for pathophysiology. 1524 37

Post kala-azar dermal leishmaniasis (PKDL) is a dermatosis caused by persistence of Leishmania donovani parasites in the skin following apparently successful treatment of visceral leishmaniasis. The distribution of PKDL lesions in Sudanese patients often mirrors the clothing habits of those affected. It is most severe in or confined to the sun-exposed parts of the skin. It is well established that elimination of Leishmania parasites requires activation of parasitised macrophages by a Th1 immune response and that the latter is depressed by ultraviolet light (UVB). In this paper, we hypothesized that UVB light might be a key player in the pathogenesis of PKDL. This paper links observations made in the field with immunological data that are compatible with this hypothesis. We therefore investigated patients with PKDL immunologically for a possible role of UVB exposure in the pathogenesis of this condition. We marshal evidence that the changes in the tissues are compatible with the effects of UVB light and it is probable that UVB appears to be a key factor in the pathogenesis of PKDL. Immunopathologically the lesions were characterized by an influx of various inflammatory cells. The number of CD1a (Langerhans' cells) was decreased, they lost their dendrites, their HLA-DR and B7-1 expression was down regulated while B7-2 was expressed. Others have shown that Langerhans' cells with these features result from UVB exposure and that such cells are unable to present antigen to Th1 cells while retaining the capacity to present antigen to Th2 cells. Various cytokines known to be induced by UVB radiation could be demonstrated in PKDL lesions. Of these IL-10, TGF-beta, IL-12, IL-4 and TNF-alpha were found in different quantities. The Th-1 cytokine IFN-gamma was constantly present. The tissue origin of the Th-1 cells in PKDL is unknown. We believe that the antagonistic action of the different cytokines is the cause of the inflammation and chronicity of PKDL.
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PMID:The pathogenesis of post kala-azar dermal leishmaniasis from the field to the molecule: does ultraviolet light (UVB) radiation play a role? 1638 55

Psychological stress is believed to exacerbate inflammatory skin disease but the underlying mechanisms are poorly understood. We investigated the impact of acute social stress--Trier public speaking test--on: epidermal Langerhans' cell (LC) frequency; and cutaneous nerve fiber expression of protein gene product (PGP) 9.5 and calcitonin gene-related peptide (CGRP). Thirty-six healthy volunteers each had a pair of baseline 6 mm biopsies taken from sun-protected buttock skin. A second pair of biopsies was taken from contralateral buttock 4 hours (n=5) or 24 hours (n=15) after the Trier stressor. Controls (n=16) did not perform the Trier and had biopsies 24 hours apart. One of each pair of biopsies (baseline; 4 or 24 hours) was processed for counts of epidermal CD1a(+) LC; the other examined for PGP 9.5 and CGRP expression. We observed a significant (P<0.01) 16.4% reduction in epidermal LC frequency 24 hours post-stressor as compared with baseline; there was no significant change from baseline in non-stressed controls. At 24 hours, PGP 9.5 and CGRP were increased (P=0.025) and reduced (P=0.03), respectively, from baseline in the stressed group compared with controls. These data suggest that acute social stress reduces epidermal LC frequency and modulates cutaneous neuropeptide expression thereby supporting the concept of a "brain-skin" axis.
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PMID:The effects of acute social stress on epidermal Langerhans' cell frequency and expression of cutaneous neuropeptides. 1798 31

Psoriasis is a chronic inflammatory skin disease characterized by epidermal hyperproliferation and infiltration of inflammatory leukocytes. The aim of this study was to clarify the role of innate immunity involving dendritic cells (DC) and keratinocytes in psoriasis. We immunohistochemically examined the expression of DC markers such as CD1a, CD83, CD207 (Langerin), CD208 (DC-LAMP) and CD209 (DC-SIGN) in psoriatic skin and gamma-interferon (IFN-gamma)/12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated keratinocytes in vitro. CD208 was strongly expressed in basal and suprabasal layer keratinocytes in addition to DC in the perivascular lesions of the psoriatic dermis. Furthermore, the enhanced expression of CD208 in the perinuclear lesions of IFN-gamma-/TPA-stimulated keratinocytes was observed in vitro. Because a defect of the granular layer in psoriatic lesions has been recognized, increased expression of lysosome-related CD208 in the basal and suprabasal keratinocytes of psoriatic lesions might represent aberrant epidermal differentiation. Additionally, these CD208-positive keratinocytes possessing putative antigen-processing activity might play a key role as antigen-presenting cells in psoriatic skin.
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PMID:Increased expression of CD208 (DC-LAMP) in epidermal keratinocytes of psoriatic lesions. 1933 88


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