Molecular characterization of CD34+ human hematopoietic progenitor cells.
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Antigens, CD↗
Biomedical subjects
H Strobl
Publications and source records attributed to H Strobl.
Pilomatrixoma of the cheek: report of case.
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Cheek↗
Flow cytometric analysis of intracellular CD68 molecule expression in normal and malignant haemopoiesis.
CD68 molecules are heavily glycosylated lysosomal membrane constituents of unknown function with strong expression in monocytes and macrophages. Using flow cytometry, we quantified expression levels of CD68 molecules in normal and malignant haemopoietic cells. CD68 molecules are intensely expressed in the cytoplasm and weakly on the surface of mature CD14+ monocytes. CD68 expression seems to start very early during granulomonopoietic differentiation. Virtually all myeloperoxidase (MPO)+ bone marrow cells coexpress CD68 and similar proportions of CD34+ progenitor cells weakly express CD68 or MPO molecules. During further differentiation, CD68 expression is strongly up-regulated in early MPO+ precursor cells which lack lactoferrin (LF) and CD14 molecules. Compared to these, more mature MPO+LF+ bone marrow and peripheral blood granulocytes express considerable lower levels of CD68. In-line with this broad expression, all investigated acute myeloid leukaemia (AML) cases, classified as FAB M1-M5, were CD68 positive, and compared to normal CD34+ bone marrow cells. CD34+ AML blast cells expressed increased levels. CD68 expression is, however, not restricted to cells of myeloid origin, because a subset (40 +/- 15%, n = 6) of CD19+ peripheral blood B-lymphocytes and 50% of B-ALL are also weakly positive. In contrast, normal CD3+ lymphocytes lack (< 3%, n = 6) CD68 and only low proportions (6 +/- 3%, n = 6) of CD56+ NK cells are CD68+. Also, all investigated T-ALL cases (n = 6) lacked CD68.
Acute Disease↗
B lymphocytes with latent EBV infection appearing in long-term bone marrow cultures (HLTBMCs) from haematological patients induce lysis of stromal microenvironment.
Human long-term bone marrow cultures (HLTBMCs) are a valuable in vitro model for studying the role of the haemopoietic microenvironment. Here we report the spontaneous appearance of EBV-positive B cells in 6/40 HLTBMCs from patients with various haematological diseases after 3-5 months of culture. After subcultivation of these cells, a novel type of cell line could be characterized, which displayed surface markers and morphological features typical for EBV transformed B-cell lines. As the deproteinized and ultrafiltrated culture supernatants of these cell lines were found to contain an agent with stroma toxic properties, they were termed SSB lines (stroma-toxic-agent-secreting B-cell lines). This agent also exhibited a colony-inhibitory activity on in vitro myelopoiesis and erythropoiesis. These properties are typical for the two polyamines spermine and spermidine which were detected at elevated levels in the culture supernatants of SSB lines. The hypothesis that latent presence of EBV in bone marrow may induce an increased synthesis of spermine and spermidine, which are known to be associated with malignant haematological diseases and bone marrow aplasia, is discussed.
B-Lymphocytes↗
[Phenotypic characterization of human hematopoietic stem cells].
Mature hematopoietic cells of all lineages are derived from committed progenitor cells, which in turn are thought to originate from pluripotential stem cells. On the basis of in vitro clonogenic assay systems, different stages within this progenitor or stem cell compartment have been identified. Using cell separation techniques, it has been shown that all in vitro clonogenic cells are included in the minor population of bone marrow or peripheral blood cells expressing the CD34 molecule. CD34 positive cells have further been subdivided into subsets of clonogenic cells by their coexpression of certain characteristic molecules. Based on these immunophenotypic features, it has been shown that most immature multipotential clonogenic cells may be separated from the majority of already lineage committed colony forming cells. Additionally, within the committed progenitor compartment, molecules have been described allowing the specific identification of the earliest stages of granulomonocytic, erythroid or lymphoid cell differentiation. Apart from these lineage or differentiation stage specific molecules, CD34+ cells express a number of molecules that are supposed to function as cytoadhesion structures or cytokine receptors enabling these cells to interact with their stroma microenvironment.
Antigens, CD↗
[Corrective movement of a palatal impacted canine tooth: methodology and outcome of a combined oral surgery/orthodontic procedure].
In 24 patients, 31 palatal impacted maxillary canines were brought in position using the same surgical and orthodontic concept. After temporal surgical exposure a little silver chain was attached at the crown of the canine, the mucoperiostal flap was repositioned, and the canine was moved into its position by innovative orthodontic treatment means. The combined method is described intensively. With respect to the applied technique the results indicate that according to the criteria of periodontal status, vitality, bone support, root resorption and occlusion no differences exist to free erupted canines despite a mean orthodontic correction of 36.7 degrees.
Cuspid↗
Flow cytometric analysis of cell-surface and intracellular antigens in leukemia diagnosis.
New technology allows highly sensitive flow cytometric detection and quantitative analysis of intracellular antigens in normal and malignant hemopoietic cells. With this technology, the earliest stages of myeloid and lymphoid differentiation can easily and reliably be identified using antibodies directed against (pro-)myeloperoxidase/MPO, CD22 and CD3 antigens, respectively. Particularly for the analysis of undifferentiated acute myeloblastic leukemia (AML) cells, the immunological demonstration of intracellular MPO or its enzymatically inactive proforms is highly relevant, since other myeloid marker molecules such as CD33, CD13, or CDw65 are either not restricted to the granulomonocytic lineage or appear later in differentiation. By combining MPO staining with staining for lactoferrin (LF), undifferentiated cells can be distinguished from the granulomonocytic maturation compartment in bone marrow, since LF is selectively expressed from the myelocyte stage of differentiation onward. The list of informative intracellular antigens to be used in leukemia cell analysis will certainly expand in the near future. One candidate, intracellular CD68, has already been tested by us, and results are presented. Also dealt within this article are surface marker molecules not (as yet) widely used in leukemia cell analysis but with the potential to provide important additional information. Among them are the surface structures CD15, CD15s, CDw65, CD79a (MB-1), CD79b (B29), CD87 (uPA-R), and CD117 (c-kit).
Antigens, CD↗
Synergistic growth inhibitory and differentiating effects of trimidox and tiazofurin in human promyelocytic leukemia HL-60 cells.
Increased ribonucleotide reductase (RR) activity has been linked with malignant transformation and tumor cell growth. Therefore, this enzyme is considered to be an excellent target for cancer chemotherapy. We have examined the effects of a newly patented RR inhibitor, trimidox (3,4,5-trihydroxybenzohydroxamidoxime). Trimidox inhibited the growth of human promyelocytic leukemia HL-60 cells with an IC50 of 35 mumol/L. Incubation of HL-60 cells with 50 mumol/L trimidox for 24 hours decreased deoxyguanosine triphosphate (dGTP) and deoxycytidine triphosphate (dCTP) pools to 24% and 39% of control values, respectively. Incubation of HL-60 cells with 20 to 80 mumol/L trimidox even up to a period of 4 days did not alter the distribution of cells in different phases of cell cycle. Sequential incubation of HL-60 cells with trimidox (25 mumol/L) for 24 hours and then with 10 mumol/L tiazofurin (an inhibitor of inosine monophosphate dehydrogenase) for 4 days produced synergistic growth inhibitory activity, and the cell number decreased to 16% of untreated controls. When differentiation-linked cell surface marker expressions were determined in cells treated with trimidox and tiazofurin, a significantly increased fluorescence intensity was observed for the CD 11b (2.9-fold). CD 33 (1.9-fold), and HLA-D cell surface antigens. Expression of the transferrin receptor (CD71) increased 7.3-fold in cells treated with both agents, compared with untreated controls. Our results suggest that trimidox in combination with tiazofurin might be useful in the treatment of leukemia.
Benzamidines↗
Peripheral blood hematopoietic progenitor cells of cytokine-stimulated healthy donors as an alternative for allogeneic transplantation.
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Adult↗
Signaling and induction of enhanced cytoadhesiveness via the hematopoietic progenitor cell surface molecule CD34.
The transmembrane glycoprotein CD34 shows a highly restricted expression on a crucial subset of hematopoietic cells. We show here that engagement of particular determinants of CD34 can lead to signal transduction and to enhanced adhesiveness of CD34+ hematopoietic cells. Monoclonal antibodies (MoAbs) directed against O-sialoglycoprotease-sensitive epitopes of CD34 (QBEND10, ICH3, BI.3C5, MY10) but not MoAbs against O-sialoglycoprotease-resistant epitopes (9F2, 8G12) induce actin polymerization in KG-1a and KG-1 cells and strongly enhanced cytoadhesiveness. The capacity to induce adhesion requires cellular energy, divalent cations, and intact cytoskeleton but not de novo protein synthesis. The observed cytoadhesion seems at least in part to be caused by a concomitant activation of the beta 2 integrin cytoadhesion pathway. It can be significantly inhibited with lymphocyte function-associated antigen-1 and intercelluar adhesion molecule-1 antibodies. Protein kinase inhibition analyses suggest that the pathways initiated by engagement of the CD34 molecule with certain CD34 MoAbs involves protein tyrosine kinases but that protein kinase C is not critically involved.
Antibodies, Monoclonal↗
Granulocytic sarcoma of the prostate as the first manifestation of a late relapse of acute myelogenous leukemia.
We describe a 68-year-old patient who developed granulocytic sarcoma of the prostate 9 years after complete remission following successful treatment of acute myelogenous leukemia (FAB, M2). PCR analysis of bone marrow samples in first remission and at the time of relapse detected an AML1/ETO rearrangement typical for AMLs with t (8;21). The CD56 antigen was not expressed on the leukemic cells. Systemic chemotherapy led to a short-lasting regression of the tumor, but the patient subsequently developed overt bone marrow relapse and died during chemotherapy. While granulocytic sarcoma as a primary manifestation of AML is well known, as the first manifestation of relapse it appears to be very uncommon.
Aged↗
Modulation of pyrogen-induced upregulation of endothelial cell adhesion molecules (CAMs) by interleukin-4: transcriptional mechanisms and CAM-shedding.
The pyrogens interleukin 1 (IL-1), tumor necrosis factor (TNF), and bacterial lipopolysaccharides (LPS) are known to increase endothelial cell (EC) adhesiveness for leukocytes by stimulating surface expression of various adhesion molecules. IL-4, a product of activated T-cells, was shown to affect pyrogen-mediated regulation of EC adhesion molecule surface expression. In the present study, we investigated the effect of IL-4 on pyrogen-induced upregulation of the cell adhesion molecules (CAMs) ICAM-1 (intercellular cell adhesion molecule-1), ELAM-1 (endothelial leucocyte adhesion molecule-1), and VCAM-1 (vascular cell adhesion molecule-1) in cultured human umbilical vein EC (HUVEC). Surface expression of adhesion molecules was quantified by flow cytometry, HUVEC mRNA content was estimated by Northern blot analysis, and ICAM-1 antigen in conditioned media was measured by ELISA. Incubation of HUVEC with IL-1 (100 U/ml), TNF (500 U/ml), and LPS (10 micrograms/ml) caused significant increase in ICAM-1, ELAM-1, and VCAM-1 surface expression; IL-1 caused about an eightfold increase in ICAM-1 expression, about a 13-fold increase in ELAM-1 surface expression, and about a fourfold increase in VCAM-1 expression. Coincubation of pyrogens with IL-4 (500 U/ml) differentially influenced their proadhesive effects on the HUVEC surface. In the presence of IL-4, IL-1-induced ICAM-1 upregulation was reduced, ELAM-1 upregulation was not significantly influenced by IL-4, and induction of VCAM-1 was enhanced by IL-4.(ABSTRACT TRUNCATED AT 250 WORDS)
Base Sequence↗
[Reconstructive procedures for improving the facial contour].
From 1986 to 1992 in the Department of Oral and Maxillofacial Surgery in Innsbruck, in 102 patients with a congenital or acquired deformity of the face, 128 augmentations with Hydroxylapatite granules (in 36 cases) or with Ethylenoxid-sterilised lyophilised cartilage (in 92 cases) have been performed. Hydroxylapatite granules, filled in a Vicryl-tube and implanted subperiosteal solely, proved to be at well tolerated material and consistently in form. In different areas of the face implanted Ethylenoxid-sterilised lyophilised cartilage showed no loss of substance up to now.
Cartilage↗
Monocytes do not make mast cells when cultured in the presence of SCF. Characterization of the circulating mast cell progenitor as a c-kit+, CD34+, Ly-, CD14-, CD17-, colony-forming cell.
Mast cells (MC3) belong to the hemopoietic system and arise from hemopoietic precursor cells. Human MC progenitors can be detected in the bone marrow as well as in the peripheral blood (pb) and are responsive to the mast cell growth factor SCF, the ligand of the c-kit tyrosine kinase receptor. However, little is known about the subsets of cells that become committed to and differentiate into mature human MC. In this study, the identity of the circulating MC progenitor, previously felt to be a monocyte (Mo) or basophil (Ba), was investigated. For this purpose, CD14+ pb monocytes, CD17+ pb basophils and CD34+ cord blood cells were purified to homogeneity (> 95%) from mononuclear cells (normal adult donors, n = 17, cord blood, n = 2) by counter-flow centrifugation followed by cell sorting with mAb. In the presence of rhSCF, MC developed in long term suspension culture from pure CD34+ cells but not from pure Mo, pure Ba, or Ly (MC-tryptase levels on day 42: CD14+ Mo: 3.7 +/- 0.8 vs CD17+ Ba: 3.2 +/- 0.5 vs Ly: 2.0 +/- 1.5 vs control: 196.5 +/- 92.5 ng/ml, p < 0.001). Depletion of CD34+ cells from MNC resulted in a loss of MC in long term suspension culture, whereas depletion of either Mo, Ba, or Ly did not. In methyl-cellulose cultures in the presence of rhSCF, MC and tryptase could be detected in pure (CFU-mast) and mixed (CFU-myeloid/mast) MC colonies. Together, MC do not originate from circulating Mo, Ba, or Ly. The circulating MC progenitor is a CD34+, c-kit+, Ly-, CD14-, CD17- colony-forming cell. This is the first definitive demonstration that mast cells are replenished directly from early hemopoietic progenitors and thus form a unique cell lineage within the hemopoietic system.
Antigens, CD↗
Myeloperoxidase expression in CD34+ normal human hematopoietic cells.
Bone marrow (BM), adult peripheral blood (aPB), and umbilical cord blood (CB) samples contain small proportions of CD34+ cells that include virtually all hematopoietic progenitor cells. Myeloperoxidase (MPO) is considered to be selectively expressed in cells committed to granulomonocytic differentiation. Using flow cytometry and an antibody against MPO, we studied at which stage of normal hematopoietic differentiation CD34+ cells being to express MPO. We consistently observed a characteristic MPO/CD34 staining pattern and found that 35% +/- 9% of CD34+ BM cells express MPO. The MPO+ CD34+ subset and the CD33+ CD34+ subset were of similar size and overlapped considerably. MPO+ CD34+ cells expressed high levels of HLA-D molecules, were weakly CD71/transferrin receptor positive to negative, were CD45RA+ and lacked the CD45RO isoform of the leukocyte common antigen. Additionally, MPO+ CD34+ cells were on average larger in size than MPO- CD34+ cells. Virtually identical phenotypic features have previously been described for in vitro colony-forming granulomonocytic progenitor cells. In vitro clonogenic assays performed with MPO-enriched and MPO-depleted fractions of CD34+ BM cells performed by us also suggest, but do not formally prove, that at least a portion of MPO+ CD34+ cells have in vitro cluster (10 to 50 cells/colony) or colony-forming unit granulocyte-macrophage (> or = 50 cells/colony) forming capacity. CD34+ cells from CB and aPB resembled CD34+ BM cells in that considerable proportions of them coexpressed CD33. However, in contrast to BM, CD34+ cells from CB and aPB samples lacked significant MPO expression and, in line with this, the majority of them (CB, 59% +/- 7%; aPB, 66% +/- 5%) coexpressed CD45RO.
Adult↗
Flow cytometric analysis of intracellular myeloperoxidase and lactoferrin in leukemia diagnosis.
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Antigens, CD↗
[Mobilization of circulating hematopoietic stem cells by granulocyte colony stimulating factor after chemotherapy in multiple myeloma].
Due to the relatively low tumour cell contamination of peripheral blood in patients with multiple myeloma, autologous transplantation of circulating stem cells may have theoretical advantages over autologous bone marrow transplantation. In four patients with multiple myeloma who where considered potential candidates for autologous stem cell transplantation G-CSF (600 micrograms/day) was administered following chemotherapy in order to maximally increase the number of circulating progenitor cells during haematopoietic rebound and to facilitate progenitor cell harvest by leukapheresis. In two previously untreated patients the administration of G-CSF following chemotherapy according to the UVA protocol (ultralan, vincristine, adriamycin) greatly increased circulating haematopoietic stem cells from 247 to 7552 CFU-GM/ml in patient 1 and from 173 to 6361 CFU-GM/ml in patient 2, which by far exceeded the increase in progenitor cells following chemotherapy alone, namely only to 594 and 317 CFU-GM/ml in patient 1 and patient 2, respectively. In two repeatedly pretreated patients, the combination of UVA and G-CSF was much less effective. Progenitor cells increased from 144 to 735 CFU-GM/ml in patient 3 and only from 222 to 232 CFU-GM/ml in patient 4. In both cases, however, mobilization of haematopoietic progenitor cells by G-CSF following cyclophosphamide (50 and 70 mg/kg body weight, respectively) led to much higher CFU-GM peak values (5324 in patient 3 and 2245 in patient 4), thus allowing an adequate harvest of mononuclear cells and CD 34+ cell numbers to achieve, in all probability, the prompt and complete reconstitution of haematopoiesis in case of transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)
Antigens, CD↗
Expression of identical E2A/PBX1 fusion transcripts occurs in both pre-B and early pre-B immunological subtypes of childhood acute lymphoblastic leukemia.
The translocation t(1;19)(q23;p13) in pediatric patients with acute lymphoblastic leukemia (ALL) was demonstrated in early reports to result in a consistent fusion between the E2A and PBX1 gene sequences and in the expression of a uniform, chimeric E2A/PBX1 mRNA with transforming potential. More recent observations suggested that cytogenetically identical t(1;19) translocations can result in the transcription of different mRNA species and that expression of the E2A/PBX1 message may be restricted to patients with the t(1;19) who display a pre-B phenotype of ALL. To further assess the correlation between the immunologic subtypes of the disease and specific genetic alterations, we have performed cytogenetic and molecular analyses in 221 children with B-lineage ALL. Expression of the chimeric E2A/PBX1 message was detected in 21 patients. Out of 14 patients, in whom cytoplasmic immunoglobulin (cig) analyses were available, no less than four had a cig- B-cell precursor ALL, whereas 10 displayed a cig+ B-ALL immunophenotype. These findings are at variance with a recent report in which expression of the E2A/PBX1 message was linked exclusively to a subset of patients who displayed a cig+ pre-B-cell precursor phenotype of ALL. In seven cases diagnosed before 1986, cig analyses were not available, and consequently E2A/PBX1 expression could not be correlated to a particular immunological subtype of B-cell precursor ALL. Our results have important implications for the detection of residual disease in pediatric patients where expression of the typical E2A/PBX1 mRNA may occur both in cig+ (pre-B) and cig- (early pre-B) immunologic subtypes of ALL.
Child↗