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)

To better define the clinical and pathologic features of interdigitating dendritic cell sarcoma (IDCS), we report 4 cases, including the first reported in the tonsil. There were 2 male and 2 female patients (mean age, 70 years). Sites of tumor included 1 case each in the right cervical lymph node, left axillary lymph node, right tonsil, and right inguinal lymph node. Histologically, all showed diffuse effacement of the lymphoid tissue by pleomorphic round to spindled cells with convoluted nuclei and abundant eosinophilic cytoplasm. All were immunoreactive for S-100, CD68, lysozyme, and vimentin. CD45 was positive in 3 cases and CD1a in 1 case. Fascin was positive in 3 cases. Other immunostains, including CD3, CD20, CD21, CD30, actin, cytokeratin, and HMB-45, were negative. Ultrastructurally, the tumor cells were elongated and showed indented nuclei, variable numbers of lysosomes, and interdigitating cytoplasmic processes. Follow-up was available for all cases. One patient died of widespread disease 2 months after diagnosis. One was alive with metastatic lung disease at 12 months. Two patients were disease free at 5 and 9 months.
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PMID:Interdigitating dendritic cell sarcoma. A report of four cases and review of the literature. 1129 8

Interdigitating dendritic cell sarcoma is an extremely rare neoplasm that mainly occurs in the lymph nodes. We report a case of interdigitating dendritic cell sarcoma arising from the spleen, a previously unreported site for interdigitating dendritic cell sarcoma. An 87-year-old woman, visiting Ashigara Hospital with complaints of palpitation and dyspnea, was found to have pancytopenia and low proteinemia. Abdominal ultrasonography and CT scanning demonstrated severe splenomegaly with heterogeneous enhancement. She received a splenectomy under the clinical diagnosis of a splenic tumor. Grossly, the spleen was markedly enlarged, with confluent massive nodules. Microscopically, the normal architecture was effaced with diffuse proliferation of large pleomorphic cells arrayed in a somewhat sheet-like pattern. Erythrophagocytosis was commonly observed. Immunohistochemical studies showed that the tumor cells were positive for S-100 protein, fascin, vimentin, and CD68, but uniformly negative for CD45, B- and T-cell markers, CD1a, CD30, complement receptors, CD34, Factor VIII, HMB-45, and lysozyme. Ultrastructurally, the tumor cells possessed complex interdigitating cytoplasmic dendritic processes. Birbeck granules were absent. Based on these findings, the present case was diagnosed as interdigitating dendritic cell sarcoma. The patient died of multiple liver metastases 3 months postoperatively.
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PMID:Interdigitating dendritic cell sarcoma of the spleen: report of a case with a review of the literature. 1191 34

Langerhans cell histiocytosis (LCH) is a clonal disorder believed to be derivedfrom cells of the dendritic system. Fascin, a 55-kd actin-bundling protein, represents a highly selective marker for dendritic cells of lymphoid tissues and peripheral blood and is involved in the formation of dendritic processes in maturing epidermal Langerhans cells. Since lesional cells of LCH may represent Langerhans cells arrested at an early stage of activation, immunohistochemical expression offascin in epidermal Langerhans cells and in the lesional cells of 34 cases of LCH was evaluated in paraffin sections using an immunoalkaline phosphatase technique. Though epidermal Langerhans cells were nonreactive for fascin, lesional cells in all LCH cases exhibited immunoreactivityforfascin, CD1a, and S-100 protein. Variation in staining intensity was observed in some cases, possibly reflecting differences in cell maturation or activation. Involved tissues included bone, soft tissue, lymph node, thyroid, orbit, and extradural cranial tissue. Immunoreactivity of lesional cells of LCH for fascin supports their derivation from cells of the dendritic system and represents another alteration in the phenotype of Langerhans cells that is associated with maturation, migration, culture, or clonal expansion.
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PMID:Langerhans cell histiocytosis immunohistochemical expression of fascin, a dendritic cell marker. 1221 75

Conjunctival lymphoid follicles (CLFs), present in normal individuals, undergo hyperplasia upon conjunctival infection by a specific array of pathogens; infection-associated enlargement of draining preauricular lymph nodes suggests that conjunctival follicles participate in the afferent limb of acquired immune responses for the ocular surface. The present study was performed to delineate the structural and lymphoid anatomy of CLFs in the baboon (Papio anubis), a non-human primate conjunctival model with close similarity to the human. Conjunctiva from both eyes, along with mesenteric lymph node, spleen, tonsil, and ileum controls were harvested from ten baboons at necropsy, and studied by histochemical and immunohistochemical methods. Baboon conjunctival follicles were identified as dense oval collections of leukocytes in the substantia propria with infiltration into a thinned overlying conjunctival epithelium. Goblet cells were universally absent, the overlying mucin layer was attenuated, and the follicle-associated epithelium (FAE) demonstrated comparatively diminished alkaline phosphatase expression. The basement membrane overlying each follicle appeared discontinuous. CD4-positive T lymphocytes were distributed in parafollicular areas and to a lesser degree in follicle germinal centers. B lymphocytes formed the predominant cell in follicles, and also heavily infiltrated the FAE. B cell IgM expression was prominent in germinal centers, while IgD staining occurred in a horseshoe-shaped distribution in the follicle mantle zone. Although B cell IgA expression was noted in the non-follicular conjunctiva, IgA expression was inconspicuous within conjunctival follicles. S-100- and CD1a-positive dendritic cells were found in FAE, while fascin-positive mature dendritic cells appeared in the deeper areas of each follicle. CD68-positive macrophages were dispersed throughout the follicles. CD35-positive follicular dendritic cells were observed only in germinal centers. CLFs appear highly organized consistent with a role in the adaptive immune response to conjunctival pathogens.
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PMID:Structural and cellular architecture of conjunctival lymphoid follicles in the baboon (Papio anubis). 1274 51

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

There is a burgeoning literature on the contrasting role of intratumoral dendritic cells (DCs) and tumor-associated macrophages, making reliable identification of both cell types in clinical and experimental tissue sections important. However, because these cell types are closely related and share several differentiation antigens, their absolute distinction in tissue sections is difficult. We differentiated DCs and macrophages from monocytes in vitro, prepared cytospins and paraffin-embedded sections of the various cell populations, and tested a variety of antibodies that purportedly recognize monocytes and DCs for their capacity to react and distinguish cells after conventional formalin fixation. Cultured DCs but not macrophages were detected by fascin, DC-LAMP, and CD83 with a predictable increase in staining that paralleled their maturation. Staining by CD1a was found on immature DCs but was weak and absent on mature DCs and macrophages, respectively. CD14 and CD163 were characteristic for macrophages and absent on DCs. CD68, HLA-DR, and S100 did not discriminate between DCs and macrophages. We conclude that antigens such as HLA-DR and S100 are not in themselves sufficient for identification of DCs in formalin-fixed tissue sections, but that additional macrophage-specific (CD14, CD163) and DC-specific (CD1a, CD83, fascin, DC-LAMP) antigens should be used to distinguish cell types from each other and to provide information on their state of maturation.
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PMID:A basis for distinguishing cultured dendritic cells and macrophages in cytospins and fixed sections. 1571 17

In the adventitia of large arteries, dendritic cells are located between nerve fibers, some of which contain substance P. The aim of the present study was to examine whether neurokinin 1 receptor (NK-1R) was expressed by dendritic cells in the arterial wall. Parallel sections of aortic and carotid artery segments were immunostained with anti-NK-1R and cell-type-specific antibodies. Dendritic cells in the arterial wall expressed NK-1R, albeit at a low level. Other cells, which intensely expressed NK-1R, were located along the border between the media and adventitia. They did not co-express any dendritic cell markers, including fascin, CD1a, S100, or Lag-antigen, and were negative for CD68, CD3, and mast cell tryptase. These NK-1R(+) cells were laser-capture microdissected and studied by means of electron-microscopic analysis. The microdissected cells were in direct contact with nerve endings, and their ultrastructure was typical of the interstitial cells of Cajal present in the gastrointestinal tract. Further systematic electron-microscopic analysis revealed that the cells displaying the features typical of interstitial cells of Cajal were a basic element of the human arterial wall architectonics. Arterial interstitial cells of Cajal were negative for c-kit but they expressed vasoactive intestinal peptide receptor 1 (VIPR1). Destructive alterations of contacts between arterial interstitial cells of Cajal and nerve endings were observed in arterial segments with atherosclerotic lesions. The functional significance of the arterial interstitial cells of Cajal and their possible involvement in atherosclerosis and other vascular diseases need clarification.
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PMID:Subset of cells immunopositive for neurokinin-1 receptor identified as arterial interstitial cells of Cajal in human large arteries. 1590 5

Tumor-related sarcoid reactions were analyzed in 14 lymph nodes in comparison with sarcoidosis using immunohistochemical markers to lymphocytes (CD3, CD4, CD8, and CD20), myeloid-related protein (MRP) 8 and MRP14 (S100A8 and S100A9), angiotensin I-converting enzyme (CD143), and mature or immature dendritic cells (S100, HLA-DR, fascin, CD83, and CD1a). We found that solitary epithelioid cell granuloma (ECG) first occur between lymph sinus and T-zone and that multiple ECGs mainly occur within T-zone, whereas confluent types often occupy the whole lymph node except some residual lymphoid follicles. This pattern suggests a continuous spread and growth of ECGs in sarcoid reactions along T-zone, where antigen presentation mainly takes place. Irrespective of granuloma type, a constant invasion of freshly recruited MRP8 + and MRP14 + macrophages was observed. Similar to sarcoidosis, angiotensin I-converting enzyme expression was a constant finding in epithelioid and giant cells, suggesting a common inflammatory pathway. An increasing ratio of CD4 + to CD8 + T lymphocytes (r = 0.789, P = .001) and a decreasing number of S100 + and CD83 + dendritic cells (r = 0.787, P = .001) within ECGs correlated with granuloma growth, whereas CD1a + immature dendritic cells were never observed inside ECGs. Our findings show that sarcoid reactions represent a T-cell-mediated immune response, leading to histological appearance and cell distribution similar to sarcoidosis and other granulomatous conditions, but the mechanism is different from dendritic cell-based tumor vaccination. Furthermore, mature dendritic cells occur inside ECGs especially of early sarcoid reactions but may not be required for the enlargement and further maintenance of ECGs, in contrast to CD4 + lymphocytes.
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PMID:Inflammatory cells in the formation of tumor-related sarcoid reactions. 1594 22

In multiple sclerosis (MS), dendritic cells (DCs) recruited to the central nervous system (CNS) are thought to be involved in the regulation of autoimmune responses directed against myelin antigens. To better understand the role of DCs in CNS inflammation, we performed a detailed immunohistochemical analysis of DC maturation markers and of DC relationship to CNS-infiltrating T cells in autopsy brain tissue of patients with MS. We also investigated the presence of DCs containing myelin debris in MS lesions. Myeloid DC subsets were identified using the following markers: CD1a for immature DCs; DC-SIGN for immature and mature DCs; and fascin, CD83, DC-LAMP, and CCR7 for mature DCs. The most common finding was the presence of cells expressing DC-SIGN and containing myelin components in the perivascular cuffs of early active and chronic (both active and inactive) MS lesions. Perivascular CD1a DCs were detected in active lesions in only one of 10 patients with MS who were examined. Although less numerous than DC-SIGN DCs, cells expressing mature DC markers were consistently detected in the inflamed meninges and perivascular cuffs of most active lesions examined. CCR7 immunostaining was predominantly confined to activated microglia at the lesion edges. Some perivascular DC-SIGN cells were found in close proximity to or contacting rare proliferating lymphocytes, most of which expressed the DC-SIGN ligand ICAM-3 and CD8. These data suggest that DCs recruited and maturing in MS lesions, where self-antigens are made available by continuous myelin destruction, may contribute to the local activation and expansion of presumably pathogenic T cells.
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PMID:Dendritic cells in multiple sclerosis lesions: maturation stage, myelin uptake, and interaction with proliferating T cells. 1646 4

We have established a system for directed differentiation of human embryonic stem (hES) cells into myeloid dendritic cells (DCs). As a first step, we induced hemopoietic differentiation by coculture of hES cells with OP9 stromal cells, and then, expanded myeloid cells with GM-CSF using a feeder-free culture system. Myeloid cells had a CD4+CD11b+CD11c+CD16+CD123(low)HLA-DR- phenotype, expressed myeloperoxidase, and included a population of M-CSFR+ monocyte-lineage committed cells. Further culture of myeloid cells in serum-free medium with GM-CSF and IL-4 generated cells that had typical dendritic morphology; expressed high levels of MHC class I and II molecules, CD1a, CD11c, CD80, CD86, DC-SIGN, and CD40; and were capable of Ag processing, triggering naive T cells in MLR, and presenting Ags to specific T cell clones through the MHC class I pathway. Incubation of DCs with A23187 calcium ionophore for 48 h induced an expression of mature DC markers CD83 and fascin. The combination of GM-CSF with IL-4 provided the best conditions for DC differentiation. DCs obtained with GM-CSF and TNF-alpha coexpressed a high level of CD14, and had low stimulatory capacity in MLR. These data clearly demonstrate that hES cells can be used as a novel and unique source of hemopoietic and DC precursors as well as DCs at different stages of maturation to address essential questions of DC development and biology. In addition, because ES cells can be expanded without limit, they can be seen as a potential scalable source of cells for DC vaccines or DC-mediated induction of immune tolerance.
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PMID:Directed differentiation of human embryonic stem cells into functional dendritic cells through the myeloid pathway. 1649 50


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