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)

Inflammatory lesions of the hypophysis include lymphocytic hypophysitis, pituitary abscess, and granulomatous inflammation, with or without specific infections (i.e., sarcoidosis, mycobacteria). These lesions are known to mimic pituitary neoplasms. We report the clinical and pathologic findings in three patients who underwent transsphenoidal resection for presumed pituitary adenoma. Two were women aged 30 years (one with a 5-month history of headache, the other with a 1-year history of menstrual irregularity) and one was a 12-year-old girl with headache, nausea, and diabetes insipidus. Preoperative endocrinologic studies showed increased prolactin in one patient and normal serum thyroid stimulating hormone and prolactin levels in another. By magnetic resonance imaging (MRI), the first case had a 1.2-cm mass with increased signal on T1 and isointensity on T2, ring enhancement after gadolinium, and lateral deviation of the pituitary stalk. The second patient had a 1.1-cm "cystic" mass seen during magnetic resonance imaging with adjacent bony changes seen during computed tomography. In the third, computed tomography showed a hypodense pituitary mass that enlarged during 1-month observation. At surgery, abnormal soft tissue surrounded liquefied material in the anterior pituitary in all cases. Histologic studies showed fragments of intact normal anterior pituitary with preserved vascular and reticulin network and regions of anterior pituitary infiltrated by foamy histiocytes. Other fragments resembled granulation tissue, and some consisted of acellular debris. Histiocytes were immunoreactive for the macrophage marker CD68 and negative for S-100 and CD1a. Ultrastructurally, the normal adenohypophysis was permeated by lipid-laden macrophages. There were no well-formed granulomas or giant cells, hemosiderin, acid-fast bacilli, or fungi. Serial sections and keratin immunostains failed to identify an epithelial cyst lining or keratin among the debris. We propose the term "xanthomatous hypophysitis" for this lesion.
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PMID:Xanthomatous hypophysitis. 963 Jan 81

Lymph nodes contain nonlymphoid accessory cells including follicular dendritic cells (FDCs), interdigitating dendritic cells (IDCs) and fibroblastic reticular cells (FBRCs). Neoplasms derived from FDCs are uncommon, and those of IDC origin are even more rare. We report the clinicopathologic features of 11 reticulum cell neoplasms, including 2 of FBRC origin. There were seven male patients and four female patients ranging in age from 13 to 73 years. All cases involved lymph nodes (cervical or supraclavicular-6 cases), (abdominal--2 cases), epitrochlear (1 case); two had more than one site of involvement (cervical lymph node and mediastinum--1 case, cervical and abdominal lymph nodes--1 case). One case of FDC tumor had concomitant Castleman's disease, plasma cell variant. Each neoplasm showed similar histology with oval-to-spindle-shaped cells in a storiform or fascicular pattern. Based on immunophenotypic findings, the neoplasms were classified as FDC (five cases), IDC (two cases), FBRC (three cases), and reticulum cell neoplasm, not otherwise specified (one case). The FDC tumors showed immunoreactivity for CD21 or CD35, vimentin, and CD68. The IDC tumors showed strong positivity for S-100 protein and variable positivity for CD68 and CD1a. The cases derived from FBRCs were positive for vimentin, desmin, and smooth-muscle actin. The neoplasm classified as reticulum cell neoplasm, not otherwise specified had similar morphologic features but showed only equivocal positivity for CD68 and vimentin. Follow-up was available for 9 of 11 (82%) cases with a mean of 3.5 years. Four of five patients with FDC tumors were alive with disease when last seen; the fifth is alive and well with no evidence of disease at 4-year follow-up. One patient with IDC tumor had a recurrence in a different nodal site. Two patients with FBRC tumor were disease free at follow-up of 2 years and 8 years, respectively. The patient with reticulum cell neoplasm, not otherwise specified, was alive and disease free 8 years after diagnosis.
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PMID:Reticulum cell neoplasms of lymph nodes: a clinicopathologic study of 11 cases with recognition of a new subtype derived from fibroblastic reticular cells. 973 36

Langerhans cell histiocytosis (LCH) is a disease with a broad spectrum of clinical presentations. All of the variants have in common the proliferation of cells which are morphologically, biochemically, and immunophenotypically indistinguishable from Langerhans cells. A retrospective study of three elderly patients revealed the unique presentation of cutaneous Langerhans cell histiocytosis limited to the genitalia. These cases produced a diagnostic challenge because of their unusual clinical presentation and their morphological similarity to certain other entities, including extramammary Paget's disease and malignant melanoma, which may also show S-100-positive atypical cells. All three cases showed infiltrates of histiocytic-appearing cells with folded nuclei and moderate amounts of cytoplasm which involved the epidermis, dermis, or both. Immunoperoxidase studies using antibody to S-100, CD1a and CD68 in each case showed positive staining.
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PMID:Cutaneous Langerhans cell histiocytosis of the genitalia in the elderly: a report of three cases. 976 22

We have studied the ability of the cryopreservation and culture techniques to reduce the antigenicity of human parathyroid tissue by suppressing HLA DR bearing cells. Antigenicity was studied with an immunoperoxidase technique applied on frozen sections. Antibody against HLA DR, CD1a, CD3, CD22, CD45RA, CD68 and H et Y antigens were used. In fresh parathyroid tissue, endothelial cells, histiocytes and interstitial dendritic cells expressed HLA DR antigens. Antigenicity of cryopreserved tissue were not altered. In cultured tissue, interstitial HLA DR bearing cells have disappeared but antigenicity of endothelial cells were not modified.
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PMID:[Antigenicity of fresh, cryopreserved, or liquid-medium-preserved human parathyroid adenomas]. 976 91

We describe the morphologic, immunohistologic, and genotypic characteristics of 13 cases of true histiocytic lymphomas. Six cases presented with primary gastrointestinal involvement, five with lymphadenopathy, the other sites involved being the bone marrow and the skin. The neoplastic cells displayed large abundant eosinophilic cytoplasm, occasionally vacuolated with folded or bizarre-shaped nuclei with prominent nucleoli. Mitotic figures were numerous. Multinucleated cells were common. The pattern of growth was usually diffuse and noncohesive. Spindle cell sarcoma-like areas were evident in five cases, with a prominent foam cell component in four cases. All cases expressed histiocyte-associated markers (CD68, lysozyme, alpha-1-antitrypsin), CD45 or CD45RO, and were negative for CD1a, epithelial, and B- and T-cell lineage-specific markers. Reactivity for S-100 was observed in a variable proportion of cells in 11 cases. The proliferation fraction varied from 3 to 88%. Genotypic analysis for T-cell receptor or immunoglobulin gene rearrangement demonstrated a germline configuration in all cases. We demonstrate that true histiocytic lymphoma is a rare distinctive pathologic entity that may be defined by immunohistochemical criteria and that recognition among histiocytic disorders is important for clinical and prognosis reasons.
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PMID:True histiocytic lymphoma: a morphologic, immunohistochemical, and molecular genetic study of 13 cases. 980 31

In the defense against Mycobacterium leprae, macrophages play an essential part in the mechanism of bacterial lysis but require the presence of cytokines such as interleukin 2 and gamma interferon from lymphocytes in order to effectively kill the organisms in any number. While there have been many studies of the lymphocytes in lesions of leprosy, less attention has been given to the immunohistochemical characterization of the macrophage populations. In this study, the cutaneous lesions of 69 patients with leprosy (42 lepromatous, 5 mid-borderline, and 22 tuberculoid) were evaluated by immunohistochemistry for the expression of S100 protein, CD1a, CD68, muramidase, HLA-DR, and Factor 13a. The macrophages from lesions of polar, subpolar, and borderline lepromatous leprosy patients expressed S100 protein intensely and constantly. In contrast, the lesions of polar and subpolar tuberculoid leprosy had very few cells that were immunoreactive for S100 protein ('S100+') in the granulomas in the dermis. The macrophages in all lesions were reactive for CD68 and muramidase. In paraffin sections, macrophages of lepromatous lesions failed to stain for HLA-DR, whereas in tuberculoid lesions, they were strongly positive for HLA-DR. Three patients with histoid leprosy (relapse lesions) had lesions that were strongly positive for Factor 13a and were negative for S100 protein ('S100-'). Given the possible chemotactic and migration inhibition effects of the calcium-binding proteins of the S100 family, these data suggest a possibly important role for S100 protein in the accumulation of macrophages in lepromatous leprosy, and also reveal infection of Factor 13a + dermal dendritic cells in histoid leprosy.
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PMID:Multibacillary leprosy: lesions with macrophages positive for S100 protein and dendritic cells positive for Factor 13a. 987 Jun 71

Erdheim-Chester disease is a clinicopathologic entity defined by a characteristic pattern of symmetric osteosclerosis caused by an infiltrate of mononuclear cells that include prominent numbers of foamy histiocytes. About half of patients have extraskeletal manifestations, including involvement of the hypothalamus/posterior pituitary, orbit, retroperitoneum, skin, lung, and heart. Pulmonary involvement is an uncommon but important manifestation of Erdheim-Chester disease because it causes significant morbidity and mortality. A review of the Mayo Clinic files produced four patients with confirmed Erdheim-Chester disease in whom lung biopsy had been performed. One additional patient was included from the University of Pittsburgh. Four patients were women. The mean age was 53.6 years (range 25-70 years). All patients had bilateral and symmetric sclerotic bone lesions characteristic of Erdheim-Chester disease, although in three the skeletal abnormalities were discovered only after lung biopsy. Four patients had dyspnea, and one also had a dry cough. One patient died 17 months after diagnosis. Chest radiographs showed diffuse interstitial infiltrates in all patients, with an upper zone predominance in three. Thoracic computed tomography (CT) scans showed thickening of the visceral pleura and interlobular septa with patchy associated fine reticular and centrilobular opacities and ground glass attenuation. Lung biopsy specimens showed an infiltrate of foamy histiocytes, lymphocytes, and scattered Touton giant cells with associated fibrosis in a striking lymphatic distribution. The infiltrate involved visceral pleura, interlobular septa, and bronchovascular bundles. Immunohistochemical stains were positive for CD68 in all cases and S-100 protein in four cases. Stains for CD1a were consistently negative. Ultrastructural studies in one case showed no Birbeck granules. Although in bone the histologic features of Erdheim-Chester disease may overlap with Langerhans' cell histiocytosis, its expression in the lung is distinct. Lung involvement in Erdheim-Chester disease has emerged as a unique radiographic and histologic entity.
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PMID:Erdheim-Chester disease: clinical, radiologic, and histopathologic findings in five patients with interstitial lung disease. 988

Myxomatous tissue is a characteristic component of human coronary artery lesions, found more often in restenotic lesions. It represents a bulky accumulation of stellate-shaped cells of unknown histogenesis that are embedded in a loose stroma. We analyzed 64 atherectomy specimens containing substantial amounts of myxomatous tissue by using immunohistochemistry, in situ hybridization, and electron microscopy techniques. Stellate cells represented a heterogeneous population, sharing features of smooth muscle cells (SMCs), macrophages, as well as antigen-presenting dendritic cells. Like quiescent medial SMCs, the stellate cells in all specimens expressed high levels of SM alpha-actin message and protein and showed heterogeneity with respect to heavy-chain myosin, SM22, desmin, and vimentin. Ultrastructurally, stellate cells resembled SMCs, with some peculiarities that distinguish them from both differentiated and dedifferentiated SMCs. In contrast to quiescent SMCs, the stellate cells expressed high levels of acidic fibroblast growth factor mRNA and protein similar to cells of monocyte/macrophage lineage. However, stellate cells did not express the marker of mature macrophages, HAM56, and were heterogeneous with respect to CD68. Moreover, unlike SMCs, the stellate cells bore some of the major phenotypic markers of dendritic cells: they were S100-positive and showed various reactivity with respect to CD1a and human leukocyte antigen (HLA)-DR. Invasion of myxomatous tissue with CD45RO-positive T lymphocytes was correlated with strong expression of CD1a in these specimens. Stellate cells also expressed a pericyte marker, high-molecular-weight melanoma-associated antigen. We conclude that stellate cells of myxomatous tissue represent a specific phenotype of mesenchymal cells (possibly pericytes), which is activated to express some markers of antigen-presenting cells. These findings suggest involvement of the stellate cells in a local immune response.
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PMID:Studies on the histogenesis of myxomatous tissue of human coronary lesions. 988 70

Immunohistochemistry of acute leukaemias in bone-marrow paraffin sections is commonly thought to be useless because of the poor preservation of many lineage-related markers. The recent development of antibodies against fixative-resistant epitopes and of new antigen retrieval techniques, however, has expanded the possibility of accurately testing routine samples. To assess the relevance of paraffin section phenotyping in lineage determination, 110 examples of acute leukaemia were studied by specific antibodies against CD1a, CD3, CD15, CD20, CD34, CD68, CD79a, TdT, myeloperoxidase, glycophorin A, and factor-VIII-related antigen. The cases included 59 acute myeloid leukaemias, classified according to the FAB cooperative group criteria, 39 precursor B-cell acute lymphoblastic leukaemias (ALLs), seven T-ALLs, and five mixed precursor B-cell/myeloid acute leukaemias. The combination of the markers employed always allowed the identification of the cell lineage (myeloid, lymphoid or mixed) and, in some instances, of phenotypic profiles characteristic of distinct acute leukaemia subtypes. According to the results obtained, bone-marrow biopsy may be regarded as a reliable tool for acute leukaemia diagnosis; this observation is of practical relevance especially for the classification of cases which lack circulating blasts in the peripheral blood or showing dry tap at bone-marrow aspiration.
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PMID:Acute leukaemia immunophenotyping in bone-marrow routine sections. 1023 10

Cutaneous lymphadenoma is an uncommon basaloid epithelial tumor of uncertain histogenesis, most recently classified as a variant of trichoblastoma. Because characteristic immunohistochemical findings have been reported in trichoblastomas, we evaluated the staining patterns of five cutaneous lymphadenomas and compared the results to those of ten trichoblastomas and ten nodular basal cell carcinomas (BCCs), using antibodies to cytokeratin 20 (CK20), bcl-2, and CD34. In addition, because lymphadenomas contain intraepithelial S100-positive putative Langerhans cells, we compared staining of all tumor groups for S100 protein and CD1a. We also attempted to corroborate recent reports of CD30-positive activated lymphocytes in lymphadenomas. We identified CK20-positive Merkel cells in 3/5 lymphadenomas, 7/10 trichoblastomas, and none of the BCCs. Staining for bcl-2 accentuated the peripheral epithelial layer in all lymphadenomas and in 3/10 trichoblastomas, while the remaining trichoblastomas and all BCCs stained diffusely. There was stromal staining with CD34 in two lymphadenoma, 4 trichoblastomas, and 3 BCCs. All lymphadenomas featured numerous intraepithelial S100-positive cells which were also positive for CD1a in three cases tested. In addition, 8/10 trichoblastomas and 2/10 BCCs contained modest numbers of cells labelling for S100 and CD1a. Two of three lymphadenomas contained rare single cells resembling histiocytes faintly positive for CD30, and similar cells labelled for CD68. We conclude that the similar staining patterns of lymphadenomas and trichoblastomas support the classification of lymphadenoma as a variant of trichoblastoma. Staining with CD34 does not reliably distinguish between these tumors and BCCs. Lymphadenomas, trichoblastomas, and BCCs may all contain Langerhans' cells. The relationship between these cells and the striking lymphoid infiltrates seen in lymphadenomas is not clear. In our cases, the CD30-positive cells in lymphadenomas appear to represent histiocytes rather than activated lymphocytes.
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PMID:Immunohistochemical comparison of cutaneous lymphadenoma, trichoblastoma, and basal cell carcinoma: support for classification of lymphadenoma as a variant of trichoblastoma. 1023 76


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