Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.11.1.7 (peroxidase)
 65,474 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Integrins are cell surface molecules of importance in a wide variety of cellular functions, including morphogenesis, cell migration and cell matrix interactions. The beta-2 (B2) integrin (leukocyte integrin, CD11/CD18) subfamily comprising three members, each consisting of a shared beta subunit (CD18) non-covalently associated with unique alpha subunits (CD11a, CD11b, CD11c). In the present study, we have analysed the expression pattern of B2 integrins on the surface of human keratinocytes (HKs) in biopsies obtained from healthy volunteers, from positive tuberculin skin tests and from patients with acute urticaria (AU), lichen planus (LP), psoriasis vulgaris (PV), mycosis fungoides (MF) or purpura pigmentosa chronica (PPC). In biopsies obtained from positive tuberculin tests and from the clinically involved skin of patients with LP, PV, MF or PPC, a multifocally occurring, suprabasal peroxidase-positive reaction was observed on the membranes of the HKs when the monoclonal antibodies (MABs) Dako CD11a, Dako-p150, 95 or Dako CD18 were used. In contrast, no specific staining of the HKs was observed with the same MABs in biopsies from healthy volunteers, from patients with AU and in the uninvolved skin specimens obtained from the other patients. The HKs from PV, LP, MF, PPC and AU patients and those from the healthy subjects failed to give a positive reaction when the MAB against CD11b (OKM1) was used. Our present findings provide further evidence that HKs may be actively involved in cell adhesion processes.
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PMID:Expression of beta-2 integrin molecules on human keratinocytes in cytokine-mediated skin diseases. 135 49

This study was designed to investigate whether the expression and functional properties of leukocyte adhesion molecules (LeuCAM; CD11/CD18) are altered in human alveolar macrophages (AM) from smokers. Cells were obtained from 38 smokers (S) and 27 nonsmokers (NS) by bronchoalveolar lavage (BAL). Expression of LeuCAM on freshly isolated cells was studied using a sensitive peroxidase-antiperoxidase method with monoclonal antibodies (mAB) against CD11a, CD11b, CD11c, and CD18. The functional properties of the adhesion molecules were studied by measuring in vitro the binding of AM to the intracellular adhesion molecule-1 (ICAM-1) on human umbilical-vein endothelial cells (HUVEC). The influence of LeuCAM on the increased superoxide anion production (O2-) of smoker AM was quantified after blocking the CD18 molecule by a mAB. Compared with nonsmoker AM, significantly more AM from smokers expressed CD11b (p < 0.001), CD11c (p < 0.001), CD18 (p < 0.001), and CD11a (p < 0.004), whereas there was no difference in the expression of other common epitopes of human macrophages such as CD68, CD71, CD45, HLA-DQ, and HLA-DR. The number of AM expressing CD11a, CD11c, and CD18 showed a correlation to the total number of AM obtained by BAL (p < 0.001). Adherence of AM to HUVEC was higher for smoker than for nonsmoker AM (p < 0.05). The increased binding of smoker AM to endothelial cells could be inhibited by treating the HUVEC with a mAB against ICAM-1. The mAB anti-CD18 reduced O2- release from smoker AM by 42 +/- 5% after 120 min.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Increased number of alveolar macrophages expressing adhesion molecules of the leukocyte adhesion molecule family in smoking subjects. Association with cell-binding ability and superoxide anion production. 823 87

A novel human myeloid cell line, designated HSM-1, has been established from the pleural effusion of a patient with granulocytic sarcoma (GS) who had been followed as having primary myelofibrosis for 10 years. When he was diagnosed as having granulocytic sarcoma in dermal tissues, no evidence of malignant transformation into leukaemia was found in both the peripheral blood and bone marrow. The established cell line was positive for myeloperoxidase, Sudan black B, Naphthol AS-D chloroacetate esterase. Surface marker analysis revealed that HSM-1 expressed CD4, CD13, CD11a, CD11b, Leu8, CD49b, CD49d, CD49e, CD29 and HLA-DR. To clarify why the unusual myeloid tumours developed in non-haematopoietic tissues, we examined the capability of HSM-1 to bind to skin fibroblast layers. The HSM-1 cells were found to bind to both bone marrow stromal layers and skin fibroblast layers. Among the other myeloid cell lines tested, none was found to bind to skin fibroblast layers. These findings suggest that the GS cell line may be derived from a haematopoietic precursor cell which can bind to skin fibroblasts and is localized in non-haematopoietic tissues resulting in the formation of extramedullary myeloid metaplasia. HSM-1 is a useful tool for analysing the characteristics of granulocytic sarcoma and homing receptors for haematopoietic stem cells.
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PMID:Establishment of a novel granulocytic sarcoma cell line which can adhere to dermal fibroblasts from a patient with granulocytic sarcoma in dermal tissues and myelofibrosis. 141 99

rTNF alpha facilitates highly reproducible adherence of polymorphonuclear leukocyte (PMN) to fibrinogen-coated surfaces in a concentration- and time-dependent manner. The adhesion was maximal with 1.0 nM rTNF alpha within 40-50 min at 37 degrees C. A monoclonal antibody (1B4) directed toward the beta 2-chain of the integrin receptor for fibrinogen (CD11b, CD18) completely inhibited the rTNF alpha induced adhesion. TNF alpha caused a time-dependent secretion of the granule markers gelatinase and lactoferrin but no liberation of myeloperoxidase and minimal production of A alpha(1-21), a specific cleavage product of fibrinogen generated by elastase, as markers for the azurophilic granule. PMN adhered to fibrinogen in the presence of rTNF alpha could be further stimulated with cytochalasin B and N-formyl-methionyl-leucyl-phenylalanine (FMLP) to release azurophilic granule markers as measured by increasing MPO activity and A alpha(1-21) production over time. Thus the rTNF alpha-facilitated adherence of PMN to a fibrinogen matrix provides a system for partial activation of PMN resulting in release of markers of specific and tertiary but not azurophilic granules. Moreover, these conditions should provide an opportunity to define more clearly the signal transduction processes involved in azurophilic granule release.
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PMID:rTNF alpha facilitates human polymorphonuclear leukocyte adherence to fibrinogen matrices with mobilization of specific and tertiary but not azurophilic granule markers. 164 33

We describe a form of acute myeloid leukaemia (AML), designated AML-MO, with minimal myeloid differentiation, not included previously in the FAB classification. AML-MO cannot be diagnosed on morphological grounds alone as the blast cells are large and agranular, sometimes resembling L2 or, rarely, L1 lymphoblasts, and should be identified by the following features: negative myeloperoxidase (MPO) and Sudan Black B reaction (or positive in less than 3% of blasts), negative B and T lineage markers and expression of myeloid antigens recognized by at least one monoclonal antibody, CD13 or CD33. Other myeloid markers are also often positive and these include CD11b and the enzyme MPO demonstrated by immunocytochemistry and/or electron microscopy analysis. The findings in a group of 10 cases satisfying the criteria for AML-MO are described. AML-MO represents 2-3% of all cases of AML and 1-1.5% of all acute leukaemias. Its clinical and biological significance is not yet apparent but its identification in a larger number of cases may achieve this aim.
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PMID:Proposal for the recognition of minimally differentiated acute myeloid leukaemia (AML-MO) 139 Feb 28

Leukemic cell lines such as HL-60, U937, and KG-1 provide an excellent model for studying human myeloid differentiation. These cells can be induced to differentiate from their immature state to form cells resembling more morphologically and functionally mature monocytes, macrophages, and granulocytes. During differentiation, expression of gene products such as myeloperoxidase and the integrin cell surface antigen CD11b is decreased or increased, respectively. Thus, these cell lines constitute an excellent model system in which to study the regulation of such differentially expressed genes. However, these myeloid cell lines are refractory to transfection by calcium phosphate or diethylaminoethyl (DEAE) dextran. Here we have optimized the transient transfection of myeloid cell lines using electroporation and the firefly luciferase reporter gene driven by viral promoters. The luciferase assay is extremely sensitive; transcription that is not detectable by Northern blot or run-on assays can be measured with this system. The system can be used in combination with the inducing agent 12-o-tetradecanoylphorbol-13-acetate (TPA), thus allowing analysis of developmentally regulated genes in these cells. Preliminary results suggest that this system can be applied to study the promoter for the myeloid specific gene, CD11b.
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PMID:Optimization of transient transfection into human myeloid cell lines using a luciferase reporter gene. 165 5

We investigated the origin of leukemic progenitors in a case of the simultaneous occurrence of myelomonocytic leukemia and multiple myeloma (IgG-kappa). At presentation, myeloperoxidase and nonspecific esterase-positive myelomonocytic cells had proliferated up to 12.2 x 10(9)/liter in the peripheral blood. Bone marrow cell differentials revealed the coexistence of myelomonocytic cells (30%) and atypical plasmacytoid cells (26%). Myelomonocytic cells in peripheral blood expressed both myeloid antigens (CD11b, CD13, CD14, CD15, CD33) and T/B-lymphoid antigens (CD2, CD4, CD5, CD7, CD10, PCA-1). Bone marrow mononuclear cells (BMMC) could be divided into PCA-1 strongly positive and PCA-1 weakly positive populations, which were considered to represent myeloma cells and myelomonocytic cells, respectively; the former were CD2-positive (CD2+), CD14-, and CD15-, whereas the latter were CD2+, CD14+, and CD15+. Immunohistochemical analysis revealed that, in addition to plasmacytoid cells, a minority of myelomonocytic cells showed a positive reaction for IgG staining, and production of IgG was observed in the culture supernatant of CD14+ myelomonocytic cells in peripheral blood. Southern blot analysis revealed the presence of two identical rearrangement bands of immunoglobulin heavy chain gene in both BMMC containing myeloma cells and myelomonocytic cells and CD14+ myelomonocytic cells in peripheral blood. In a long-term methylcellulose assay, peripheral blood mononuclear cells produced large compact colonies consisting of macrophages and IgG+ plasmacytoid cells (M phi/P colonies), while BMMC produced a different type of colonies consisting of CD14+ myelomonoblasts, macrophages, and IgG+ plasma cells (Mb/M phi/P colonies) in addition to M phi/P colonies. Recloning experiments showed that primary Mb/M phi/P colonies gave rise to both secondary M phi/P and Mb/M phi/P colonies. These observations strongly suggest that common leukemic progenitors provide both myeloma and myelomonocytic leukemia cells, and the mechanism of "lineage infidelity" is probably involved in the development of their "bilineal" differentiation.
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PMID:Simultaneous occurrence of myelomonocytic leukemia and multiple myeloma: involvement of common leukemic progenitors and their developmental abnormality of "lineage infidelity". 165 17

Components involved in superoxide anion production (cytochrome b) and in cell adhesion processes (CD11b, CD11c, CD18), two early functional responses of neutrophils during acute inflammation, are intracellularly located in resting human neutrophils. We have found a correlation between secretion of gelatinase and overexpression in the plasma membrane of CD11b, CD11c, CD18 and cytochrome b upon cell activation. Gelatinase and lactoferrin were parallely released after cell activation with different stimuli, but a better correlation between antigen up-regulation and gelatinase release was obtained. Total translocation of the intracellular pool of these mobilizable molecules to plasma membrane was achieved under conditions that induced total degranulation of the gelatinase-rich granule population, whereas 50% and 90% of the lactoferrin-containing secondary granules and peroxidase-containing primary granules, respectively, remained unfused. These results suggest a mechanism by which neutrophil function can be regulated through mobilization of gelatinase-rich granules, which can be considered as a subpopulation of secondary granules.
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PMID:Mobilization of gelatinase-rich granules as a regulatory mechanism of early functional responses in human neutrophils. 167 56

Tissue lesions from eight patients with recurrent oral ulcers (ROU) were subjected to detailed immunohistopathologic studies. In five patients, a specimen of an unaffected area from the opposite site was obtained. The main inflammatory cells in situ were CD3 positive T lymphocytes, with CD4 cells forming approximately half (range 30-60%) and CD8 cells 20% (range 10-30%) of all cells. CD19 positive B lymphocytes formed 5-12% of all cells. Furthermore, 45% (range 15-65%) of all lymphoid cells had signs of previous antigenous contact and had helper/inducer CDw29 type. Suppressor/inducer CD45R cells formed only about 20% (range 7-50%) of all cells. Although this observation suggests involvement of antigen as a causative and/or triggering stimulus, elements of a non-specific inflammatory response were observed as well. Endogenous peroxidase-positive neutrophils were present at the ulcer site, and were occasionally observed intravascularly and in the extracellular matrix in areas characterized by inflammatory mononuclear cell infiltrates. Although the proportion of endogenous peroxidase-positive, recently recruited monocytes was low, CD11b and nonspecific esterase-positive mature tissue macrophages formed about 14% (range 5-35%) of all inflammatory cells in situ, particularly at the periphery of the lymphoid cell infiltrates. Mast cells were also observed in all samples studied, forming 2-5% of inflammatory cells in the richly vascularized connective tissue beneath the basement membrane. In the specimens from clinically unaffected areas, inflammatory cells were rare. Our observations stress the multifaceted nature and participation of multiple effector systems in the local tissue pathogenesis of ROU.
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PMID:Immune-inflammatory cells in recurrent oral ulcers (ROU). 168 77

An increasing number of acute leukemias coexpressed markers normally believed to be restricted to a single lineage have been found recently. This special subgroup of leukemias have drawn a lot of attention because of their biologic and clinical significance. In a study of 100 consecutive de novo ANLL patients diagnosed by FAB criteria, T-cell antigen CD7 was identified on the leukemic blasts of 13 patients, ten of whom had M1 subtype of leukemia, myeloblastic leukemia without maturation. All the patients showed positive staining with myeloperoxidase and expressed myeloid markers CD13 and/or CD33, but lacked CD11b, a marker of more mature myeloid cells. Combined staining with myeloperoxidase and CD7 of the cells from four patients revealed coexpression of both markers on the same cells. None of the patients expressed the two other T-cell antigens CD2 or CD5. All ten patients who had DNA analysis showed germline configuration of TCR beta and gamma chain genes. One patient had chromosomal translocation involving 11q23, t(11; 19) (q23; p13), which is the site frequently associated with both myeloid and lymphoid malignancies. The clinical implications of this subgroup of patients need further study on more patients, and need longer follow-up.
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PMID:A subset of acute nonlymphocytic leukemia with expression of surface antigen CD7--morphologic, cytochemical, immunocytochemical and T cell receptor gene analysis on 13 patients. 169 99


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