PubMed Health⌕ Search

Biomedical subjects

R Handgretinger

Publications and source records attributed to R Handgretinger.

At least 109 records · Page 6Linked to original sources
PubMed1994

Drug-induced changes in the expression of MDR-associated genes: investigations on cultured cell lines and chemotherapeutically treated leukemias.

The induced expression of multiple drug resistance (MDR)-associated genes as a direct response of tumor cells to antineoplastic drugs could be an important factor influencing the success of cancer chemotherapy. We investigated the effects of such compounds on mdr1/P-glycoprotein (P-gp) gene expression and drug sensitivities in the T-lymphoblastoid human cell line CCRF-CEM and MDR sublines. Thereby, we observed that actinomycin D or adriamycin administered at sublethal concentrations induced increases of mdr1 mRNA levels and resistance within 72 h. Furthermore, on leukemia cell samples collected before and after chemotherapy we checked by a complementary DNA polymerase chain reaction (cDNA-PCR) approach for similar alterations in the relative expression levels of the MDR-associated genes (a) mdr1/P-gp (b) mrp (MDR related protein), and (c) the topoisomerase II isoforms alpha and beta. We found a concomitant increase in mdr1 and mrp gene expression combined with a decreased expression of topoisomerase II alpha in the course of the second relapse of an acute lymphoblastic leukemia (ALL). This points to the emergence of at least three different MDR mechanisms in this type of leukemia unresponsive to chemotherapy. A chronic myeloid leukemia (CML) in blast crisis, however, showed combined increases in mdr1 (about 20-fold) and mrp (about four fold) gene expression after intense but unsuccessful chemotherapy over a 6-month period. Our results indicate the occurrence of induced resistance in vitro and in vivo and suggest a contribution of the newly identified ATP-binding cassette (ABC) transporter MRP in MDR.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1994

Chemotactic activity of substances derived from antibody-loaded tumor cells on granulocytes.

Chemotactic activity of granulocytes attracted by tumor cells loaded either with anti-ganglioside monoclonal antibodies (mAb) or with antibody-glucose oxidase conjugates (mAb-GO) was investigated. The melanoma cell line SK-Mel-28 which expresses the ganglioside GD3 at high density as well as the neuroectodermal cell line SK-N-LO which expresses GD2 were used for the experiments. In the presence of 50% human AB-serum, antibody-loaded tumor cells induced chemotactic activity on granulocytes, probably due to the generation of C3a/C5a which could be detected in serum incubated with anti-GD3 loaded SK-Mel-28 cells. Both compounds could also be detected in vivo in the plasma of patients suffering from neuroblastoma during therapy with anti-GD2 antibodies. In another set of experiments mAb-GO conjugates generating high amounts of H2O2 in the presence of glucose were bound to these tumor cells. A significant lipid peroxidation could be observed in the simultaneous presence of iron and ascorbate. The lipid peroxidation products were measured as thiobarbituric acid-reactive substances (TBARS) and were also shown to induce chemotactic effects on granulocytes.

ABO Blood-Group System↗
PubMed1994

Activation of cellular cytotoxicity and complement-mediated lysis of melanoma and neuroblastoma cells in vitro by murine antiganglioside antibodies MB 3.6 and 14.G2a.

Mouse monoclonal antibodies against tumour-associated gangliosides GD2 (14.G2a) and GD3 (MB 3.6) were tested to mediate antibody-dependent cellular cytotoxicity (ADCC) with various effector cells or complement-dependent cytolysis (CDC). We also evaluated the immunomodulating potential of interferons in combination with cellular cytotoxicity. Using effector:target (E/T) ratios of 40:1, ADCC with effector cells such as granulocytes or mononuclear blood cells was not detectable against melanoma cell lines GR, SK-MEL-28 and G-361 which preferentially express GD3 and bind antibody MB 3.6. Neuroblastoma cell line SK-N-LO, which was used for comparative purposes, mainly expressed GD2 and the tumour cells were killed effectively after labelling with antibody 14.G2a. Granulocytes did not show significant killing of melanoma cells by ADCC, but neuroblastoma cells were killed very efficiently. Peripheral blood mononuclear cells (PBMC) also failed to kill melanoma cells. Interferon-beta slightly stimulated PBMC and increased killing of neuroblastoma cells, but no additive effects with ADCC were detectable. Incubation of target cells with interferons produced no significant differences in susceptibility of the target cells to interferon-activated PBMC cytotoxicity. Despite the lack of effectiveness in mediating cellular cytotoxicity, GD3 antibody MB 3.6 showed strong complement-dependent cytolysis in the presence of human plasma. There were remarkable differences in individual activity and different susceptibility of the melanoma cell lines. We assume that CDC may have more activity against melanoma cells than cytotoxicity associated with various effector cells.

Animals↗
PubMed1994

[Technical aspects of autologous bone marrow transplantation].

Autologous bone marrow transplantation has become an established procedure in the treatment of malignancies. Especially in patients with hematological malignant diseases, who have no compatible allogeneic bone marrow donor or in patients with solid tumors, in whom the threshold of irreversible bone marrow toxicity is reached by the intensified chemotherapy, this procedure allows the use of a myeloablative therapy. As stem cell sources, bone marrow (BM), peripheral blood-derived stem cells (PBSC), and umbilical cord blood can be used. The risk of contaminating malignant cells in BM or PBSC can be reduced by an in vitro purging of the stem cells. In principle, two different methods exist: one is the negative depletion of contaminating tumor cells and the other is the positive selection of non-malignant hematopoietic pluripotent stem cells. Which of the purging principles will be most effective can only be answered through clinical studies.

Bone Marrow Purging↗
PubMed1994

[Autologous bone marrow transplantation].

Autologous bone marrow transplantation (ABMT) is a treatment modality increasingly used to treat a growing number of malignancies both in children and in adults. The theoretical rationale is the transfer of dose-action relationship from pharmacological theory to clinical practice. The basic principles, the important indications and the problems of this particular approach are discussed. Normally bone marrow from the iliac crest is used as stem cell source, but the possibilities of the approach become broader by using peripheral blood stem cells (PBSC). This treatment modality and its particular use in neuroblastoma is described demonstrating also the results.

Adult↗
PubMed1994

Distribution of cell adhesion molecules in decidua of early human pregnancy. An immunohistochemical study.

BACKGROUND: The aim of the study was to investigate human decidua for cell adhesion molecules involved in interactions between the various different maternal and fetal cell populations, homing of the unusual intradecidual population of CD56+ lymphocytes, and organization of the decidual extracellular matrix. EXPERIMENTAL DESIGN: First trimester human decidua from normal pregnancies was investigated immunohistochemically with antibodies against integrin subunits (alpha 1-6, alpha L, alpha M, alpha X, alpha IIb, alpha V, beta 1, beta 3, and beta 4), platelet-endothelial cell adhesion molecule, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and L-selectin. RESULTS: Endometrial glands stained for alpha 1, alpha 2, alpha 3, alpha 5, alpha 6, alpha V, beta 1, beta 3, and beta 4, and stromal cells for alpha 1, alpha 3, alpha 5, alpha 6, alpha V, beta 1, beta 3, ICAM-1, and VCAM-1. Endothelium stained for alpha 1, alpha 2, alpha 3, alpha 4, alpha 5, alpha 6, alpha V, alpha IIb, beta 1, beta 3, and beta 4; platelet-endothelial cell adhesion molecule and ICAM-1 also were found on the endothelium of a large number of blood vessels of all types, and VCAM-1 on the endothelium of a moderate number of arterioles and venules, and a few capillaries. Weak staining for E-selectin was seen in a moderate number of arterioles and venules. Large numbers of lymphocytes stained for alpha 4, alpha L, alpha M, alpha X, beta 1, and moderate or small numbers for alpha 1, alpha 3, alpha 5, alpha v, beta 3, platelet-endothelial cell adhesion molecule, ICAM-1, and L-selectin. CONCLUSIONS: Decidual stromal cells, like endometrial glands and endothelium, express integrins that bind basement membrane components. These integrins represent the basis for the formation of the pericellular basement membrane of these cells. They also bind certain glycoproteins that support outgrowth and attachment of the trophoblast in vitro. Vitronectin-binding integrins on endometrial glands, stromal cells, and endothelium may be involved in adhesion of the trophoblast through vitronectin on its surface. From our findings and published data it seems that adhesion of alpha 1 beta 2 (leukocyte function-associated antigen-1) on lymphocytes to ICAM-1 on the endothelium plays the most important role in the migration of CD56+ lymphocytes from the peripheral blood into the decidua. The expression of several beta 1 (VLA) integrins on lymphocytes suggests that these cells are activated, and, like the expression of ICAM-1 and VCAM-1 on stromal cells, probably contributes to their retention in the decidual stroma.

Cell Adhesion Molecules↗
PubMed1994

Differential responses of fetal, neonatal, and adult myelopoietic progenitors to interferon and tumor necrosis factor.

Human fetal liver (FL) and neonatal cord blood (CB) granulocyte-monocyte colony-forming progenitor cells (GM-CFC) are unique in their physiological environment and in certain proliferative and differentiative capacities. Tumor necrosis factor (TNF) and interferon (IFN) may inhibit or stimulate the growth of human bone marrow GM-CFC in vitro. The effects of recombinant human (rh) TNF-alpha, rhIFN-alpha, and rhIFN-tau on recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF)-stimulated clonogenic cultures of day 7 GM-CFC from FL and umbilical CB were compared with rhGM-CSF-stimulated GM-CFC from normal human bone marrow (BM). We demonstrate that, in comparison to BM progenitor cells, GM-CFC from both FL and CB were highly resistant to growth inhibition by all three cytokines. Furthermore, clonogenic growth of progenitors from FL and CB was markedly potentiated by IFN-tau in GM-CSF-stimulated cultures and was stimulated by IFN-tau in the absence of GM-CSF. Depletion of potential accessory cells resulted in a marked stimulatory response of CB cells to TNF-alpha, in the presence of GM-CSF, while it did not alter the responses to IFN. The stimulatory effects of IFN-tau and TNF-alpha may be indirectly mediated, at least in part, through induction of increased GM-CSF production and increased GM-CSF receptor expression by fetal cells. Divergent responses of myelopoietic cells, derived from various hematopoietic compartments, to regulatory actions of cytokines may provide a basis for further understanding the role of the environment in maturation and differentiation of granulocytes and monocytes.

Adult↗
PubMed1993

Mdr1/P-glycoprotein expression in natural killer (NK) cells enriched from peripheral or umbilical cord blood.

The sensitivity to antineoplastic agents of subpopulations of haematopoietic cells during cancer chemotherapy is an open question. The performance of natural killer (NK) cells, possibly assisting the elimination of tumour cells under drug treatment might be of particular interest. We examined the expression of the transmembrane multidrug transporter mdr1/P-glycoprotein in NK-cells (CD56+) enriched from the peripheral blood or the umbilical cord blood from healthy donors by indirect immunocytofluorescence using the monoclonal P-glycoprotein antibody C219 and a polymerase chain reaction (PCR) approach with amplimers specific for the human mdr1 cDNA. As the antibody C219 apparently cross-reacts with the human mdr3 gene product whose functions are as yet unclear we also checked expression of this gene by PCR using mdr3 specific amplimers. Distinct, but rather inhomogeneous mdr1/P-glycoprotein expression was found in NK-cells enriched from the peripheral blood. NK-cells enriched from the umbilical cord blood showed quite strong mdr1 expression levels throughout, exceeding the values found in the moderately multidrug-resistant cell line CCRF VCR 100 which is permanently cultivated in the presence of 100 ng/ml vincristine. Mdr1/P-glycoprotein expression was mirrored by lowered sensitivities of the cultivated NK-cells towards actinomycin D or adriamycin. The drug sensitivity could be modulated by treatment of the cells with the immunosuppressive drug cyclosporin A. Expression of the mdr3 gene was low or absent in all NK-cell samples examined so far.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1993

Expression of an early myelopoietic antigen (CD33) on a subset of human umbilical cord blood-derived natural killer cells.

A new subset of natural killer (NK) cells was identified in human umbilical cord blood. This subset of CD56+/CD3- NK cells co-expressed the CD33 antigen, which is present on early hematopoietic progenitors confined to the myeloid lineage. The percentage of the CD56+/CD33+ cells among the CD56+/CD3- NK cells was 7.9 +/- 6.6% (n = 27) with a range of 1.4-25.5% and a considerable individual variability. Additionally, the majority of freshly isolated CD56+/CD33+ cells co-expressed the CD2 and CD7 antigen, a minor proportion co-expressed the CD8 antigen but essentially all of the cells stained negative for CD16 and CD57. Morphological analysis of the CD56+/CD33+ cells showed the features of large agranular lymphocytes. From some of the samples, the CD56+/CD33+ NK cells were cultivated and expanded in vitro by incubation of the cells with interleukin 2 (IL-2) for up to 50 days. Morphological analysis of the cultured CD56+/CD33+ cells showed the features of large granular lymphocytes (LGL). The IL-2-expanded CD56+/CD33+ NK cells showed only a low cytolytic activity against K562 target cells, whereas most of the NK activity of the expanded cells was contributed by the CD56+/CD33- NK cells.

Antigens, CD↗
PubMed1993

Distribution of cell adhesion molecules on CD56++, CD3-, CD16- large granular lymphocytes and endothelial cells in first-trimester human decidua.

Human decidua exhibits a unique infiltrate of large granular lymphocytes (LGL) with a natural killer (NK) cell phenotype (CD56++, CD16-, CD3-). The mechanisms underlying the binding of circulating LGL to vascular endothelium in the decidua and their migration into the decidual stroma were investigated immunohistochemically in first-trimester decidua with antibodies against endothelial adhesion molecules and their counter-receptors on leukocytes. Decidual and peripheral blood LGL were also investigated by flow cytometry. In the immunohistochemical investigations, moderate to large numbers of lymphoid cells in the decidua were found to express the alpha 4 and alpha L integrin subunits, platelet endothelial cell adhesion molecule (PECAM) and intercellular adhesion molecule-1 (ICAM-1). PECAM and ICAM-1 were found on the endothelium of large numbers of decidual blood vessels of all types. Vascular cell adhesion molecule (VCAM), however, was found on the endothelium of only small to moderate numbers of arterioles and venules and a few capillaries, the latter being the main site of migration of leukocytes into the stroma. Weak staining for endothelial leukocyte adhesion molecule (ELAM) was seen only in a moderate number of blood vessels. Flow cytometry revealed expression of the alpha L integrin subunit by 72 +/- 10% and 97 +/- 3% of decidual and peripheral blood CD56+ LGL, respectively, of the alpha 4 integrin subunit by 85 +/- 7% and 90 +/- 5%, of PECAM by 40 +/- 12% and 30 +/- 15%, and of ICAM-1 by 22 +/- 10% and 1 +/- 1%.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, CD↗
PubMed1992

Case report 756: Chronic multifocal osteomyelitis.

We report the case of a young boy referred to our Department of Nuclear Medicine under the suspicion of a malignant tumor. The leading clinical symptoms were pain in the joints and loss of weight and vitality. Radiographic findings were suggestive of osteogenic sarcoma, but bone scans showed multiple increased tracer depositions along the cortex of femur and tibia, and in the lower and upper jaw. The enrichment pattern was not typical for metastases, but more probably demonstrated the multiple foci of osteomyelitis. This assumption was confirmed by the histological findings, which were diagnosed as primary chronic osteomyelitis. This rare pediatric bone disorder has been described by Giedion et al. The etiology of the disease is unknown, and therapy is discussed controversely in literature.

Child↗
PubMed1992

A phase I study of neuroblastoma with the anti-ganglioside GD2 antibody 14.G2a.

Nine patients with neuroblastoma stage IV were treated with the murine monoclonal antibody 14.G2a, directed against disialoganglioside GD2. The antibody was injected daily for 5-10 days and the total applied dosage ranged between 100 mg/m2 and 400 mg/m2. The peak serum levels of mAb 14.G2a ranged from 28 micrograms/ml to 61 micrograms/ml. Pharmacokinetic data obtained in three patients indicated that the serum elimination of mAb 14.G2a fits a two-compartment model, with an alpha-half-time (t1/2 alpha) between 0.66 h and 1.98 h and a beta-half-time (t1/2 beta) between 30.13 h and 53.33 h. All patients presented with a human anti-(mouse IgG) antibody response either during or shortly after therapy. Eight patients showed a continuous decrease in complement component C4 during therapy, as well as an initial decrease in C3c and an initial increase in C3a, all suggesting an activation of the complement cascade. Side-effects consisted of allergic reactions like pruritus, exanthema, urticaria and of severe pain, predominantly located in the abdomen and lower extremities, which required the use of continuous intravenous morphine. Four patients additionally developed a transient hypertension and one patient experienced a transient nephrotic syndrome. Three patients were treated in an adjuvant setting and are not evaluable for tumor response. Of the remaining six patients, two had a complete remission, two showed a partial remission, and two patients did not respond to treatment.

Antibodies, Anti-Idiotypic↗
PubMed1992

A simple assay for determination of iron release from ferritin in neuroblastoma cells.

A commercially available enzyme immunoassay was used to determine ferritin content and subsequently the loading and release of iron from ferritin in neuroblastoma cells. LS cells were incubated with 59Fe for 24 h, lysed, and the cytoplasmic ferritin was bound to monoclonal antibodies coupled to globules. After determination of the ferritin content the same globules with bound radioactive ferritin were measured in a gamma-counter. To illustrate the applicability of this test system, increased iron loading of cellular ferritin could be demonstrated in cycloheximide-treated cells; furthermore, release of iron was documented after incubation of LS cells with a combination of 6-hydroxydopamine and ascorbate. The assay turned out to be a simple method for determination of changes in 59Fe content of ferritin in neuroblastoma cells.

Ascorbic Acid↗