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)

We report three children who had multisystem Langerhans cell histiocytosis (LCH) with cutaneous involvement and subsequently developed juvenile xanthogranuloma (JXG). JXG appeared 3--6 years after the initial manifestation of LCH. JXG lesions, which presented as yellowish papules, revealed typical Touton giant cells and were factor XIIIa positive but S100 and CD1a negative. Non-LCH histiocyte disorders, such as JXG, are known to occur as a reaction to a variety of external stimuli such as infection and trauma. It is therefore conceivable that the inflammatory reaction associated with LCH may have precipitated the development of JXG in our patients. Alternatively, one could speculate that this association might be due to a common histogenetic precursor of the cell types involved.
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PMID:Juvenile xanthogranuloma as a sequel to Langerhans cell histiocytosis: a report of three cases. 1148 23

Neoplasms of histiocytes and dendritic cells are rare, and their phenotypic and biological definition is incomplete. Seeking to identify antigens detectable in paraffin-embedded sections that might allow a more complete, rational immunophenotypic classification of histiocytic/dendritic cell neoplasms, the International Lymphoma Study Group (ILSG) stained 61 tumours of suspected histiocytic/dendritic cell type with a panel of 15 antibodies including those reactive with histiocytes (CD68, lysozyme (LYS)), Langerhans cells (CD1a), follicular dendritic cells (FDC: CD21, CD35) and S100 protein. This analysis revealed that 57 cases (93%) fit into four major immunophenotypic groups (one histiocytic and three dendritic cell types) utilizing six markers: CD68, LYS, CD1a, S100, CD21, and CD35. The four (7%) unclassified cases were further classifiable into the above four groups using additional morphological and ultrastructural features. The four groups then included: (i) histiocytic sarcoma (n=18) with the following phenotype: CD68 (100%), LYS (94%), CD1a (0%), S100 (33%), CD21/35 (0%). The median age was 46 years. Presentation was predominantly extranodal (72%) with high mortality (58% dead of disease (DOD)). Three had systemic involvement consistent with 'malignant histiocytosis'; (ii) Langerhans cell tumour (LCT) (n=26) which expressed: CD68 (96%), LYS (42%), CD1a (100%), S100 (100%), CD21/35 (0%). There were two morphological variants: cytologically typical (n=17) designated LCT; and cytologically malignant (n=9) designated Langerhans cell sarcoma (LCS). The LCS were often not easily recognized morphologically as LC-derived, but were diagnosed based on CD1a staining. LCT and LCS differed in median age (33 versus 41 years), male:female ratio (3.7:1 versus 1:2), and death rate (31% versus 50% DOD). Four LCT patients had systemic involvement typical of Letterer-Siwe disease; (iii) follicular dendritic cell tumour/sarcoma (FDCT) (n=13) which expressed: CD68 (54%), LYS (8%), CD1a (0%), S100 (16%), FDC markers CD21/35 (100%), EMA (40%). These patients were adults (median age 65 years) with predominantly localized nodal disease (75%) and low mortality (9% DOD); (iv) interdigitating dendritic cell tumour/sarcoma (IDCT) (n=4) which expressed: CD68 (50%), LYS (25%), CD1a (0%), S100 (100%), CD21/35 (0%). The patients were adults (median 71 years) with localized nodal disease (75%) without mortality (0% DOD). In conclusion, definitive immunophenotypic classification of histiocytic and accessory cell neoplasms into four categories was possible in 93% of the cases using six antigens detected in paraffin-embedded sections. Exceptional cases (7%) were resolvable when added morphological and ultrastructural features were considered. We propose a classification combining immunophenotype and morphology with five categories, including Langerhans cell sarcoma. This simplified scheme is practical for everyday diagnostic use and should provide a framework for additional investigation of these unusual neoplasms.
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PMID:Tumours of histiocytes and accessory dendritic cells: an immunohistochemical approach to classification from the International Lymphoma Study Group based on 61 cases. 1212 Dec 33

Distinguishing desmoplastic melanoma (DM) from scar tissue on routine microscopy can be difficult, especially in re-excision specimens, and S100 immunohistochemistry has been recommended as a useful adjunct. The purpose of this study is to evaluate the extent and nature of S100 positivity in scars. In this study, formalin-fixed paraffin archival tissues were evaluated with immunohistochemistry. Ten re-excision specimens of previously biopsied nonnevomelanocytic lesions were immunostained with the S100 and CD57 (Leu 7) antibodies. In 9 of the 10 cases, the scars contained S100-positive spindle cells, but there were no cases with CD57+ cells. Ten re-excised atypical nevi and 10 re-excised melanomas were also immunostained for the S100 protein, and all 20 cases contained S100-positive spindle cells within the scars. There was a trend toward quantitatively more S100-positive spindle cells in these nevomelanocytic re-excisions. To evaluate the nature of the spindle cells, scars from two of the nonnevomelanocytic re-excisions were further analyzed utilizing immunostains for glial fibrillary acidic protein, HMB-45, Melan-A, CD1a, factor XIIIa, and neuron specific enolase. In both scars, neuron specific enolase diffusely stained the fibroblast population, but the remaining immunostains were negative in the scar. The presence of S100-positive spindle cells in scars represents a potential diagnostic pitfall, particularly in the evaluation of re-excision specimens of DM.
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PMID:S100-positive spindle cells in scars: a diagnostic pitfall in the re-excision of desmoplastic melanoma. 1214 9

A 29-year-old woman had a 2-month history of an enlarging lesion over her left frontal bone following minor trauma. CT scan showed an osteolytic lesion with an overlying soft tissue mass, thought to be an unhealed skull fracture with pseudomeningocele. Left frontal craniotomy revealed a soft tissue mass, which was resected. Histologic examination revealed multinucleated giant cells mixed with Langerhan's cells that showed the characteristic "coffee bean nuclei." Eosinophils were scant. Immunostaining for CD1a and S100 revealed strong positive staining primarily in the Langerhans' cells while giant cells and inflammatory cells were negative. Immunostaining for CD68, in contrast, stained the osteoclast-like giant cells and macrophages. Electron microscopy confirmed the presence Birbeck granules. The final diagnosis was Langerhans' cell histiocytosis (histiocytosis X) of the skull.
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PMID:February 2002: 29-year-old woman with a skull mass for 2 months. 1214 8

Veiled cells (VC) present in afferent lymph transport antigen from the periphery to the draining lymph nodes. Although VC in lymph form a heterogeneous population, some of the cells clearly belong on morphological grounds to the Langerhans cell (LC)/ dendritic cell (DC) series. Here we show that culturing monocytes for 24 hrs while avoiding plastic adherence (polypropylene tubes) and avoiding the activation of NADPH oxidase (blocking agents) results in the generation of a population of veiled accessory cells. The generated VC were actively moving cells like lymph-borne VC in vivo. The monocyte (mo)-derived VC population existed of CD14(dim/-) and CD14(brighT) cells. Of these the CD14(dim/-) VC were as good in stimulating allogeneic T cell proliferation as immature DC (iDC) obtained after one week of adherent culture of monocytes in granulocyte-macrophage-colony stimulating factor (GM-CSF)/interleukin (IL)-4. This underscores the accessory cell function of the mo-derived CD14(dim/-) VC. Although the CD14(dim/-)VC had a modest expression of the DC-specific marker CD83 and were positive for S100, expression of the DC-specific markers CD1a, Langerin, DC-SIGN, and DC-LAMP were absent. This indicates that the here generated CD14(dim/-) VC can not be considered as classical LC/DC. It was also impossible to turn the CD14(dim/-) mo-derived VC population into typical DC by culture for one week in GM-CSF/IL-4 or LPS. In fact the cells died tinder such circumstances, gaining some macrophage characteristics before dying. The IL-12 production from mo-derived CD14(dim/-) VC was lower, whereas the production of IL-10 was higher as compared to iDC. Consequently the T cells that were stimulated by these mo-derived VC produced less IFN-gamma as compared with T cells stimulated by iDC. Our data indicate that it is possible to rapidly generate a population of CD14(dim/-) veiled accessory cells from monocytes. The marker pattern and cytokine production of these VC indicate that this population is not a classical DC population. The cells might earlier be related to the veiled macrophage-like cells also earlier described in afferent lymph.
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PMID:Accessory cells with a veiled morphology and movement pattern generated from monocytes after avoidance of plastic adherence and of NADPH oxidase activation. A comparison with GM-CSF/IL-4-induced monocyte-derived dendritic cells. 1218 52

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

Dendritic cells (DCs) are bone-marrow derived 'professional' antigen presenting cells (APC). They are considered as the most potent APC able to induce primary immune responses. DC efficiently capture and process proteic and non-proteic antigens. They are widely distributed throughout the body and occupy sentinel positions such as epithelia. Establishment of an immune response against cancer may depend of the capacity of DCs to transfer (to capture, to process and to present) tumor antigens into regional lymph nodes where they can induce a specific response leading to tumor rejection. Because host 'professional' DCs are one of the most important elements in the induction of specific anti-tumor responses and lymph nodes are the places where the immune response takes place, we investigated the densities of DCs within regional metastasis-free lymph nodes from 47 patients with different malignant epithelial tumors as comparing with lymph nodes from 11 patients without malignancies using an immunohistochemistry method with anti-S100 protein, CD86 and CD1a antibodies. By means of morphometric analysis, we observed that S100+ and CD1a+ DCs densities in regional lymph nodes from cancer patients were significatively decreased as compared with control lymph nodes (P<0.0001 and 0.003, respectively). S100+ DCs and CD86+ DCs densities in lymph nodes draining cancer were similar. Taken together, these data indicated that lymph nodes draining cancer had significantly less CD1a+ DCs than S100+ and possibly CD86+ DCs. These findings may represent another mechanism by which tumors evade the immune recognition.
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PMID:Human regional lymph nodes draining cancer exhibit a profound dendritic cell depletion as comparing to those from patients without malignancies. 1241 31

We report an exceptional case of a histiocytic sarcoma presenting as a primary isolated spleen tumor in a 71-year-old woman. The neoplastic cells in the cords and sinuses of the red pulp formed multiple lobulated tumors, which were detected in vivo by ultrasound scan. The medium cells, large cells and the giant cells expressed CD68, a histiocyte-associated marker, lysozyme and S100 protein. All these cells were negative for B- and T-cell markers, cytokeratins, melanosome markers (HMB45) and CD1a (Langerhans' cells). Many tumor cells displayed strong erythrophagocytosis and sometimes lymphocytophagocytosis. In addition, numerous histiocytes with morphology indistinguishable from reactive macrophages also exhibited a strong erythrophagocytosis, and were found in the tumor as well as in the normal splenic parenchyma. Despite multi-agent chemotherapy, the patient suffered from a relapse in the liver, with a rapid fatal outcome. A literature review showed that such a primary splenic presentation with multiple tumors is rare. In contrast, in systemic malignant histiocytosis, secondary spleen involvement occurs more frequently but with diffuse infiltration. The association with a reactive histiocytosis with erythrophagocytosis corresponds to "histiocytic medullary reticulosis", as previously described by Scott and Robb-Smith.
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PMID:Primary histiocytic sarcoma of the spleen associated with erythrophagocytic histiocytosis. 1274 73

M cells are found in intestinal follicle associated epithelium. Studies into the physiological and pathological roles of human M cells have been hampered by the lack of well-substantiated, specific markers for these cells. A critical literature review suggests the following molecules may potentially serve as such markers: CK7, FcaR (CD89), S100, CD1a, CD21, CD23, sialyl Lewis A, and cathepsin E. Normal ileum, appendix and colorectum were studied using paraffin-embedded, formalin-fixed tissue and immunohistochemistry for these 8 markers. Cathepsin E immunohistochemistry was also performed on cases of colorectal adenocarcinoma, colorectal adenoma, colorectal hyperplastic/metaplastic polyp, lymphocytic colitis, collagenous colitis, pseudomembranous colitis and active ulcerative colitis. Of the 8 markers tested, only cathepsin E appeared to be specific to follicle associated epithelium (expressed by cells with and without M cell morphology) and follicular crypt epithelium; this specificity was limited to the colorectum. Focal epithelial expression of cathepsin E was seen in adenocarcinoma, adenoma, hyperplastic/metaplastic polyp, ulcerative colitis and pseudomembranous colitis. In conclusion, cathepsin E is a specific marker of normal colorectal follicle associated epithelium and follicular crypt epithelium though is not specific to M cells within these compartments. None of the other 7 markers studied is exclusively expressed by human M cells.
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PMID:An immunohistochemical study and review of potential markers of human intestinal M cells. 1277 11

Langerhans cell histiocytosis (LCH) is a neoplastic proliferation of Langerhans cells that occurs in a range of nodal and extranodal sites. Scattered reports of LCH within the thymus exist, typically among children within the setting of multifocal, multisystem disease. Rare cases of isolated LCH involving the thymus have occurred in adult patients with myasthenia gravis. We report a case of unifocal LCH involving the thymus in a middle-aged woman with a history of a resected leiomyosarcoma but no evidence of myasthenia gravis. Computed tomographic scans revealed an anterior mediastinal mass, which was excised and measured 9.0 cm. Histologic and immunophenotypic findings (CD1a, S100, and Fascin positive and CD68 negative) were consistent with LCH. To our knowledge, this is the first example of LCH occurring in a patient with a history of soft tissue sarcoma and one of the rare reported examples of LCH presenting as a large isolated lesion in the thymus of a nonmyasthenic adult.
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PMID:Langerhans cell histiocytosis involving the thymus. A case report and review of the literature. 1282 60


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