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R Handgretinger

Publications and source records attributed to R Handgretinger.

At least 127 records · Page 7Linked to original sources
PubMed1992

Mdr1/P-glycoprotein, topoisomerase, and glutathione-S-transferase pi gene expression in primary and relapsed state adult and childhood leukaemias.

In a variety of adult and childhood leukaemia cell samples collected at different states of the disease, we analysed in a series of sequentially performed slot-blot or Northern-blot hybridisation experiments the expression of genes possibly involved in multiple drug resistance (MDR) (mdr1/P-glycoprotein, DNA topoisomerase II, glutathione-S-transferase pi), and the expression of the DNA topoisomerase I and histone 3.1 genes. Occasionally, P-glycoprotein gene expression was additionally examined by indirect immunocytofluorescence using the monoclonal antibody C219. No significant difference in mdr1/P-glycoprotein mRNA levels between primary and relapsed state acute lymphocytic leukaemias (ALL) was seen on average. Second or third relapses, however, showed a distinct tendency to an elevated expression of this multidrug transporter gene (up to 10-fold) in part well beyond the value seen in the moderately cross-resistant T-lymphoblastoid CCRF-CEM subline CCRF VCR 100. Increased mdr1/P-glycoprotein mRNA levels were also found in relapsed state acute myelogenous leukaemias (AML), and in chronic lymphocytic leukaemias (CLL) treated with chlorambucil and/or prednisone for several years. Topoisomerase I and topoisomerase II mRNA levels were found to be very variable. Whereas in all but one case of CLL topoisomerase II mRNA was not detected by slot-blot hybridizations, strong topoisomerase I and topoisomerase II gene expression levels, frequently exceeding the levels monitored in the CCRF-CEM cell line, were seen in many cell samples of acute leukaemia. If topoisomerase II mRNA was undetectable, expression of topoisomerase I was clearly visible throughout. These observations might be valuable considering the possible treatment with specific topoisomerase I or topoisomerase II inhibitors. Significant positive correlations were found (i) for topoisomerase I and histone 3.1 gene expression levels in general (P less than 0.001), and (ii) in the CLL samples additionally for the expression levels of the mdr1 gene, and the histone 3.1, topoisomerase I, and glutathione-S-transferase pi genes, respectively.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1992

The decidua of early human pregnancy: immunohistochemistry and function of immunocompetent cells.

Like the endometrial stroma, the decidua contains lymphoreticular cells, and these are probably involved in immunological interactions between the conceptus and the mother. Lymphoreticular cells in decidual tissue obtained from 12 patients undergoing therapeutic abortion of an intact pregnancy at 6-10 weeks' gestation were investigated in this study. Immunophenotyping with a broad panel of monoclonal antibodies revealed various subpopulations of lymphoreticular cells. Macrophages (Ki-M6+, Ki-M7+, Ki-M8+, KP1+, MAC 387+ and Ki-M1P+) represented the largest fraction of intradecidual lymphoreticular cells. CD3+ and CD8+ lymphocytes were found in moderate numbers and CD4+ cells in small numbers. The majority of the intradecidual lymphoid cells exhibited an unusual phenotype [CD7+, CD2+, CD56+, triple negative (CD3-, CD4-, CD8)]. The distribution of these unusual lymphocytes mirrored that of the so-called endometrial stromal granulocytes. A few of these stromal granulocytes reacted with the macrophage-associated antibody KP1, but not with Ki-M1P, another macrophage marker. This was confirmed by immuno-electron microscopy. The finding that intradecidual CD3+ lymphocytes express neither the alpha/beta nor the gamma/delta heterodimer of the T cell antigen receptor was unexpected. However, these cells did express the alpha/beta heterodimer after in vitro culture with PHA-P and recombinant exogenous interleukin-2. No stimulated T lymphocytes expressing activation antigens could be detected. B lymphocytes, T and B immune accessory cells and CD15+ granulocytes were found only in small numbers or were absent. Amongst cells expressing NK cell markers, CD57+ and CD16+ cells were found in small to moderate numbers, while CD56+ cells were detected in large numbers.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1991

Increased susceptibility of IFN-gamma-treated neuroblastoma cells to lysis by lymphokine-activated killer cells: participation of ICAM-1 induction on target cells.

We have investigated the effect of interferon-gamma (IFN-gamma) treatment of neuroblastoma cells on the susceptibility to lysis by lymphokine-activated killer (LAK) cells and examined the participation of cell-adhesion molecules on the target cells in LAK cell lysis. Untreated neuroblastoma cells expressed lymphocyte-function-associated antigen 3 (LFA-3) and neural-cell-adhesion molecule (NCAM), but did not express MHC-class-I, MHC-class-II, or intercellular-adhesion molecule I (ICAM-I). IFN-gamma treatment of neuroblastoma cells induced the expression of MHC-class-I and ICAM-I antigens, but did not affect the expression of MHC-class-II, LFA-3, and NCAM. This was accompanied by an increased susceptibility to lysis by LAK cells. Anti-ICAM-I antibody inhibited partially the increased sensitivity of IFN-gamma-treated neuroblastoma cells to LAK cell lysis, and blocked completely the increase in binding of LAK cells observed after IFN-gamma treatment of the target cells. These results suggest that the increased LAK sensitivity of IFN-gamma-treated neuroblastoma cells is partially attributable to the induction of ICAM-I on neuroblastoma cells and indicate that post-binding events also play a role in the increased sensitivity to LAK cell lysis observed after IFN-gamma treatment.

Cell Adhesion Molecules↗
PubMed1991

Effect of a chimeric anti-ganglioside GD2 antibody on cell-mediated lysis of human neuroblastoma cells.

An anti-GD2 ganglioside human/mouse chimeric monoclonal antibody, ch14.18, like its murine counterpart, 14.G2a, was shown to bind to human neuroblastoma cells. This chimeric antibody proved to be more effective than 14.G2a in mediating the lysis of neuroblastoma cells with human effector cells, such as granulocytes and natural killer cells within the peripheral blood mononuclear cell population. A comparison of these two effector cell populations isolated from the same donor revealed granulocytes to be more effective than peripheral blood mononuclear cells in lysing neuroblastoma cells, which were coated with monoclonal antibody ch14.18. Addition of recombinant human granulocyte-macrophage colony-stimulatory factor increased ch14.18-mediated lysis of neuroblastoma cells by granulocytes but not by peripheral blood mononuclear cells. In fact, granulocytes were effective in mediating lysis of neuroblastoma cells coated with ch14.18 irrespective of whether they were obtained from normal adults or from neuroblastoma patients.

Animals↗
PubMed1991

Cytogenetic and molecular characterization of a newly established neuroblastoma cell line LS.

A new human neuroblastoma cell line (LS) that originated from an abdominal tumor of a 16-month-old girl is presented; it was classified, according to Evans, as being stage III. Morphological (dense-core particles) and biochemical characteristics (dopamine-beta-hydroxylase, acetylcholinesterase, neuron-specific-enolase) confirmed the diagnosis. In addition to a slightly variable modal chromosome number of 48 or 49 (because of marker-chromosomes and autosomal trisomies), cytogenetic analysis revealed two constantly appearing chromosomes with homogeneously stained regions (HSR's). The karyotype remained constant over 50 passages in vitro [49,XX, -12, +der5, + 17, + mar1, + mar2]. Double minutes were a rare phenomenon and appeared only in a few metaphases. In situ hybridization showed that some of the HSR's consisted of amplified N-myc copies. The distribution of the N-myc copies according to in situ hybridization signals along the HSR's was compared with the data of Southern and Northern blotting analyses.

Abdominal Neoplasms↗
PubMed1991

Application of the murine anti-Gd-2 antibody 14.Gd-2a for diagnosis and therapy of neuroblastoma.

We have tested the sialoganglioside monoclonal antibody Gd-2a for scintigraphic diagnostic and for immunotherapy in children with neuroblastoma stage IV. We could confirm tumor sites with Gd-2a scans in 1/2 children. Doses of 20-60 mg/m2 were administered daily for 5-10 days. 2/2 children with multiple tumor sites showed significant tumor regression. Four children, treated preventively, are still in clinical remission. One child showed tumor progression despite Gd-2a treatment. Adverse effects included itching, rashes, and pain.

Adolescent↗
PubMed1990

Susceptibility of multidrug-resistant human leukemia cell lines to human interleukin 2-activated killer cells.

Considering the possibility to overcome drug resistance by other treatment strategies than chemotherapy we investigated the susceptibility of three independently selected multidrug-resistant sublines of the T-lymphoblastoid leukemic cell line CCRF-CEM to lymphokine-activated killer (LAK) cells. We found that two of the multidrug-resistant sublines were significantly less susceptible targets to LAK cells. A third one, however, was as susceptible as the parental CCRF-CEM cell line. Moreover, a multidrug-resistant subline that reverted to an almost drug-sensitive phenotype was observed to be also revertant for resistance against LAK cells. We found an inverse relationship between the expression of the mdr1 gene (P-glycoprotein) and the susceptibility to LAK cells. Verapamil, a calcium channel blocker, while increasing the drug sensitivity of a multidrug-resistant subline, did not induce a reversal of the suppression of LAK susceptibility. The possibility of enhanced resistance to LAK cells of multidrug-resistant cells should be taken into account when one is looking for therapy strategies to overcome multidrug resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1990

Reduction of N-myc expression by antisense RNA is amplified by interferon: possible involvement of the 2-5A system.

Expression of myc-box genes can be reduced by Interferon (c-myc in Daudi cells) or Retinoic acid (N-myc in neuroblastoma cells). Interferon did not reduce N-myc expression in neuroblastoma cells. However, after transfection of the human neuroblastoma cell line LS with a vector, providing the Cadmium inducible expression of an antisense N-myc transcript, drastic reduction of N-myc RNA was achieved in these cells by incubation with Cadmium and Interferon. Treatment with Cadmium alone resulted in a comparably small reduction of N-myc transcripts in these cells. Interferon alone did not appreciably affect N-myc expression. Reduction of N-myc was accompanied with reduced cell proliferation and morphological differentiation. It is assumed that most of the inhibitory effects observed are mediated by the Interferon inducible 2-5A system.

2',5'-Oligoadenylate Synthetase↗
PubMed1990

Establishment and characterization of a cell line (Wa-2) derived from an extrarenal rhabdoid tumor.

A new human cell line (Wa-2) derived from an extrarenal rhabdoid tumor has been established. The cell line grows as a monolayer consisting of round- and spindle-shaped cells. Injection of cells into nude mice results in the growth of solid tumors within 2 wk of inoculation. These solid tumors have the microscopic appearance similar to that of the original tumor from which the cell line was derived. Moreover, the tumor cells have all the features of rhabdoid tumors, including the intracytoplasmatic hyaline globules, large prominent nucleoli, and inclusion bodies made up of whorls of fibrillary material. Transplanted tumor cells stain positive for vimentin, cytokeratin, actin, and desmin and negative for myoglobin and neuron-specific enolase. Karyotyping of the cell line at different passages and cells derived from the transplant tumors consistently revealed a diploid number of chromosomes with a reciprocal translocation between chromosomes 18 and 22 [t(18;22) (q21;p11.2)]. In fibroblasts derived from the patient, no translocation could be found. Culturing the cells in the presence of 1-beta-D-arabinofuranosylcytosine induces differentiation, characterized by the outgrowth of neuron-like processes and the morphological appearance of cells similar to neuroblasts. Southern blot analysis showed no amplification of the N-myc oncogene. Since no published cell line derived from rhabdoid tumors exists, this cell line should be helpful to further elucidate the biology and histological origin of the malignant rhabdoid tumor.

Animals↗
PubMed1990

In vitro and in vivo effect of interleukin-2 on the 2',5'-oligoadenylate synthetase activity of peripheral mononuclear blood cells.

The in vitro and in vivo influence of interleukin-2 (IL-2) on 2',5'-oligoadenylate (2-5A) synthetase activity and natural killer (NK) activity of peripheral mononuclear blood cells (PBMCs) was investigated. Incubation of PBMCs in vitro with IL-2 resulted in a considerable secretion of interferon-gamma (IFN-gamma) and in a significant elevation of 2-5A synthetase activity, as well as NK activity. Neutralizing monoclonal anti-IFN-gamma antibodies inhibited the elevation of 2-5A synthetase activity, but not the IL-2-induced augmentation of NK activity. Additionally, 2-5A synthetase and NK activity of PBMCs was measured in a child with neuroblastoma that was treated with recombinant IL-2 by continuous intravenous application. During the treatment, NK activity against the NK-sensitive cell line K 562 and against autologous tumor cells was not augmented. However, a significant increase of 2-5A synthetase activity in PBMCs was observed during IL-2 treatment, whereas there was no detectable serum level of IFN-gamma. We conclude that measuring 2-5A synthetase activity in patients treated with IL-2 may be helpful in monitoring the immunomodulatory effects of IL-2 on immune effector cells.

2',5'-Oligoadenylate Synthetase↗
PubMed1989

Resistance to methotrexate and multidrug resistance in childhood malignancies.

Resistance to drugs, either primary or acquired, is a main problem in cancer chemotherapy. The paper summarizes our results in regard to resistance to methotrexate and multiple drug resistance in human cell lines of pediatric malignancies and in children with resistant cancer. In cell lines as well as in children we could demonstrate amplification of the gene coding for dihydrofolate reductase as a cause for resistance to MTX. Procedures to overcome drug resistance such as treatment with high dose MTX and leucovorin rescue are discussed. The increased expression of the mdrl gene coding for the P-glycoprotein is related to multidrug resistance. This could be shown in cell lines and in children. The expression decreased when the drug, used for induction of resistance, was omitted for a few weeks from the cell culture medium. Readdition of the drug caused a rapid increase of expression. For the first time data in children are presented which demonstrate the amplification of the gene coding for dihydrofolate reductase or increased expression of the mdrl gene as cause of drug resistance. The clinical implications of these findings are discussed.

Adolescent↗
PubMed1989

Lysis of neuroblastoma cells by the ADCC-reaction: granulocytes of patients with chronic granulomatous disease are more effective than those of healthy donors.

Granulocytes from healthy donors lyse human neuroblastoma cells in the ADCC-reaction using antibody MAb 14.18 directed to ganglioside GD2 present on the surface of most neuroblastoma cells. Addition of catalase, superoxide dismutase and azide do not impair this process. Granulocytes from patients with chronic granulomatous disease (CGD) kill neuroblastoma cells even better than those collected from healthy donors. These results indicate that reactive oxygen intermediates (ROI) are not involved in killing of neuroblastoma cells using MAb 14.18, and that granulocytes from patients with CGD may compensate for defects in generation of reactive oxygen intermediates by more effective oxygen-independent killing mechanisms. One patient with CGD was treated with interferon-gamma. During and after treatment, generation of ROI could not be detected and neuroblastoma cell killing was not significantly altered.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1989

In vitro induction of lymphokine-activated killer (LAK) activity in patients with neuroblastoma.

Therapy of disseminated neuroblastoma remains an unsolved problem in pediatric oncology. Therefore, new therapeutic approaches have to be developed for this malignancy. In this paper, we investigated the possibility of the in vitro generation and expansion of lymphokine-activated killer (LAK) cells in patients with disseminated neuroblastoma. Although the patients had very low Natural Killer (NK) activity, it was possible to induce LAK activity in peripheral mononuclear lymphocytes (PMNC) by incubation with Interleukin-2 (IL-2). Moreover, the PMNCs could be expanded up to 50-fold in the presence of Interleukin-2 while maintaining or even increasing their LAK activity. The target cells were neuroblastoma cell lines and, in one case, autologous neuroblastoma cells. Additionally, it was possible to induce LAK cell activity against autologous neuroblastoma cells in bone marrow-derived mononuclear cells.

Bone Marrow↗