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R Handgretinger

Publications and source records attributed to R Handgretinger.

144 records · Page 8Linked to original sources
PubMed1989

Bone marrow transplantation in children with neuroblastoma.

Neuroblastoma is the third most frequent malignant tumor in childhood. One-third of the patients over one year of age at the time of diagnosis suffer from the disseminated form (stage IV). Despite highly aggressive chemotherapy survival rates are poor. One hundred and eighty-seven patients with neuroblastoma stage IV have been treated according to the German protocol NB 85. The probability of disease free survival is only 15% after 70 months. Treatment strategy in our protocol includes autologous and allogeneic bone marrow transplantation (BMT) for patients with stage IV (and greater than 1 year old). Twenty-two patients were grafted (7 allogeneic and 15 autologous). The conditioning regimen consisted mainly of high-dose melphalan (180 mg/m2) and total body irradiation (TBI) (3.4 Gy). Survival rates are discussed in the context of the chemotherapy protocol. Our own experience with autologous BMT is poor, despite of different purging methods. For this reason we decided to focus on allogeneic BMT. We have grafted five patients within the last 3 years. Three of them are alive and well, on died from veno-occlusive disease 70 days after BMT, and the remaining patient, grafted from a syngeneic donor, died from relapsing tumor. The main problem in neuroblastoma stage IV is resistance to chemotherapy. Intensification of the conditioning regimen or double autografting leads to a rate of toxic deaths close to 20% (Zucker, EBMT 1987) which is not tolerable. New improvements in the conditioning regimen have to be found to increase the effect of BMT.

Bone Marrow Transplantation↗
PubMed1989

Interferon-gamma upregulates the susceptibility of human neuroblastoma cells to interleukin-2-activated natural killer cells.

The influence of interferon-gamma on the susceptibility of neuroblastoma cells in cell-mediated killing was investigated. Neuroblastoma cells were only weakly susceptible targets for peripheral mononuclear cells. However, enrichment of natural killer (NK) cells or activation of NK cells with interleukin-2 resulted in a considerable increase of neuroblastoma cell lysis. Pretreatment of neuroblastoma targets with interferon-gamma additionally increased the susceptibility to enriched NK cells as well as to interleukin-2-activated NK cells. The conjugate formation between enriched NK cells and the neuroblastoma targets was not affected by the pretreatment of the targets with interferon-gamma. Concomitantly, treatment of the neuroblastoma targets with interferon-gamma resulted in a strong induction of otherwise poorly expressed major histocompatibility complex (MHC) class I antigen expression. These results suggest that the increased expression of MHC class I antigens on target cells is not always correlated with decreased sensitivity for NK cells but can also be followed by an increased susceptibility for NK cells.

Antigens, Neoplasm↗
PubMed1987

Mediation of human NK-activity by components in extracts of Viscum album.

Viscum album extracts (Iscador) were investigated for their potency to influence NK cytotoxicity in vitro. In vitro short term cytotoxicity assays (4 h) with human peripheral mononuclear cells (PMNC) and human K 562 tumor cells showed a drastic enhancement of NK cytotoxicity in the presence of V. album extracts. The presence of the V. album components during tumor cell lysis was essential since preincubation of PMNC with V. album extract followed by thorough washing did not lead to enhancement of NK cytotoxicity. One responding effector cell was identified as a member of the large granular lymphocyte (LGL) family carrying both Leu 7 and Leu 11 surface markers. Furthermore, monocytes depleted of LGL, but not differentiated macrophages, showed a weak enhancement of their cytolytic activity in the presence of V. album extract. Fractionation of V. album extracts revealed two active fractions one (C1) with about 3-4000 D and the other (C2) less than 1000 D. Both components enhanced NK cytotoxicity of LGL (Leu 7+, Leu 11+) as well as of monocytes showing enhancing effects also against moderately NK-sensitive tumor cell lines.

Adjuvants, Immunologic↗
PubMedDate not supplied

Effects of granulocytes on human neuroblastoma cells measured by chemiluminescence and chromium-51 release assay.

We investigated whether polymorphonuclear leukocytes (PMN) are able to kill human neuroblastoma cells either directly or if coated with antibody MAb 14.18 that recognizes ganglioside GD2 present on the cell surface of most neuroblastoma cells. Neuroblastoma cells could not be destroyed directly, whereas in the antibody-dependent reaction (ADCC-reaction) they were easily eliminated. In order to answer the question whether reactive oxygen intermediates are involved in this process, chemiluminescence measurements were performed. Compared to the signals that could be measured using opsonized zymosan as stimulus, only weak CL-signals could be registered during the ADCC reaction. Pretreatment of PMN with granulocyte-macrophage colony stimulating factor (GM-CSF) enhanced the CL-signals, catalase and SOD reduced it; however, cell killing was only slightly influenced in the presence of catalase and superoxide dismutase. These data suggested that reactive oxygen compounds do not play a prominent role in the killing process. Definitive evidence for this suggestion could be obtained using PMN from a patient with chronic granulomatous disease (CGD): MAb 14.18 coated neuroblastoma cells could be killed effectively, but no CL-signal could be registered, either in the ADCC-reaction or using opsonized zymosan as stimulus.

Catalase↗
PubMedDate not supplied

Isolation and phenotypic characterization of CD117-positive cells.

Mononuclear cells derived from cord blood were stained using the CD1 17-specific, fluorochrome-labeled monoclonal mouse antibody 95C3. Additional staining was performed using an isotype-specific rat-anti-mouse antibody, labeled with supermagnetic microparticles. Target cells were enriched by the technique of magnetic cell separation, MACS. The resulting cell population contained 96.5% (+/-1.7% S.D.) CD1 17-expressing cells (n = 12) with different levels of CD117 antigen expression. Using flow cytometry, two cell populations differing in size were found. A majority (93%) of cells with high forward scatter revealed a phenotype positive for CD117 and CD34. Isolated cells revealed a high fraction of hematopoietic progenitors (16%). The technique presented allows for an alternative approach of stem cell enrichment and might be useful in autologous transplantation of cells with hematopoietic properties.

Antigens, CD34↗
PubMedDate not supplied

Infants with stage 4 neuroblastoma: the impact of the chimeric anti-GD2-antibody ch14.18 consolidation therapy.

BACKGROUND: Antibody treatment is considered tolerable and potentially effective in the therapy of neuroblastoma. We have analyzed the clinical data of infants < 1 year with stage 4 neuroblastoma with regard to the consolidation treatment. PATIENTS AND METHODS: Infants < 1 year with stage 4 neuroblastoma who completed initial treatment (6-8 chemotherapy cycles followed either by 4 cycles low dose oral chemotherapy or high dose chemotherapy with stem cell transplantation) without event were eligible for this trial. Consolidation therapy consisted of 6 cycles of antibody ch14.18 (20 mg/m(2) x d ch14.18 for 5 days every 2 months) or 12 months oral maintenance chemotherapy (MT). RESULTS: Of 59 evaluable patients, 31 received a total of 159 ch14.18 cycles, 16 received MT instead, and 12 had no further treatment. Fever (47 % of cycles), abnormal CRP without infection (25 %), rash (23 %), cough (16 %), and pain (8 %) were the main side effects. Univariate analysis found no difference in event free survival (3-year-EFS 80.5 +/- 7.1 %, 87.5 +/- 8.3 %, and 75.0 +/- 12.5 % for patients treated with antibody ch14.18, MT, and no further therapy, p = 0.433) and overall survival (3-year-OS 90.1 +/- 5.4 %, 93.8 +/- 6.0 %, and 91.7 +/- 8.0 % for patients treated with antibody ch14.18, MT, and no further therapy, p = 0.931). Multivariate analysis failed to demonstrate an advantage of antibody treatment. CONCLUSION: The outcome of infants with stage 4 neuroblastoma is good. Consolidation treatment with ch14.18 was tolerable but associated with fever, elevated CRP, rash, cough, and pain as side effects. Compared to oral maintenance chemotherapy and no consolidation treatment, ch14.18 treatment had no impact on the patients' outcome which confirms the results found in children > 1 year.

Administration, Oral↗
PubMedDate not supplied

A comparison between three graft manipulation methods for haploidentical stem cell transplantation in pediatric patients: preliminary results of a pilot study.

Transplantation of hematopoietic stem cells from mismatched related donors makes a potential donor available for every child in need of stem cell transplantation. Here, we compare three different graft manipulation methods in patients with leukemias and lymphomas: positive selection of stem cells with either CD34 (n = 39) or CD133-coated magnetic microbeads (n = 14) and a new strategy which depletes T- and B-cells through the use of CD3- and CD19-coated microbeads (n = 11). Median purity of stem cells was comparable after CD34 (+)-selection and CD133 (+)-selection, whereas stem cells were only slightly enriched after CD3 (+)/CD19 (+)-depletion (97.5 %, 93.4 % and 1.02 %). Indirect depletion of T-cells by positive selection resulted in 1 x 10 (4) (median) residual CD3 (+)-cells/kg (0.7-3 x 10 (4)). Patients with CD3/CD19-depleted grafts received 3.2 x 10 (4) (median) (0.7-16 x 10 (4)) residual T-cells/kg. Those grafts also comprised NK-cells (median number: 86 x 10 (6)/kg), dendritic cells and monocytes/granulocytes. Primary engraftment of the stem cell products was comparable after CD34- and CD133-selection (85 and 72 %). In the CD3/CD19 group, 91 % had a primary engraftment. After reconditioning, all patients (64/64) were finally engrafted. Patients with CD34-selected or CD133-selected grafts had similar incidences of a GvHD II-IV (3 and 7 %), whereas a GvHD was slightly increased in patients receiving CD3/CD19-depleted cells (27 %). Reconstitution of CD3 (+) T-cells was faster in the CD3/CD19 group than in the CD34 or CD133 group. These preliminary results indicate, that CD3/CD19-selected grafts may be advantageous regarding engraftment and immunoreconstitution. Since effector cell with potential antileukemic activity are cotransfused, such grafts may be suited in particular for patients with insufficient remission.

AC133 Antigen↗
PubMedDate not supplied

Adenoviral infections after transplantation of positive selected stem cells from haploidentical donors in children: an update.

UNLABELLED: We present updated results of stem cell transplantation with highly purified stem cells from haploidentical parental donors and infection with human adenovirus (HAdV) post stem cell transplantation (SCT). Survival post SCT is primarily determined by relapse, infections and far less by GvHD or other transplant related mortality. During the immune reconstitution the host is at significant risk for severe viral infections. HAdV infection is especially in children an important complication post SCT, with significant morbidity and mortality despite new antiviral treatment strategies. Although control of infection seems to require T-cells, the characterization of HAdV-specific T-cells post SCT has not been introduced in surveillance and treatment decisions. METHODS: Therefore we evaluated the impact of HAdV-infections on the survival between 1995 and 2004 (n = 63) and studied the occurrence of adenovirus-specific T-cells in children with (n = 9) and without (n = 9) HAdV-infection post allogeneic SCT and in healthy donors (n = 53). After stimulation ex-vivo with HAdV-antigen IFN-gamma secreting T-cells were analyzed by flowcytometry and defined as HAdV-specific T-cells. RESULTS: Until day 180 post SCT the cumulative incidence of all lethal viral infections (HAdV n = 5, cytomegalovirus n = 3, herpes simplex virus n = 1) was 16 % for the whole cohort of patients. Cumulative incidence of HAdV-associated mortality was 8.5 %. Cumulative incidence of all lethal viral infections could be now reduced from 16 % to 8 % in conjunction with new surveillance- and therapeutic-strategies. Children with HAdV-associated mortality all had no specific T-cells, although reconstitution of absolute lymphocyte counts exceeded 300/microl within 30 days post transplant. Patients who cleared HAdV infection had normal frequencies of HAdV-specific T-cells until day 200 post SCT. CONCLUSION: In summary adenovirus specific T-cell reconstitution should be monitored in patients after SCT to limit the use of anti viral chemotherapy and help to identify those patients that would benefit from new therapeutic strategies like adoptive transfer of virus specific T-cells.

Adenovirus Infections, Human↗
PubMedDate not supplied

Haploidentical stem cell transplantation in patients with pediatric solid tumors: preliminary results of a pilot study and analysis of graft versus tumor effects.

Pediatric patients with relapsed metastatic tumors have a poor prognosis and new treatment strategies are warranted. We present preliminary results of a pilot study, evaluating the feasibility and toxicity of transplantation of haploidentical T and B cell depleted grafts with high numbers of NK cells. 6 patients with relapsed metastatic neuroblastomas (n = 4), rhabdomyosarcoma (n = 1) or Ewing's sarcoma (n = 1) after previous autologous transplantation received CD3/CD19 depleted grafts from mismatched family donors with a median number of 16 x 10 (6)/kg stem cells, 167 x 10 (6)/kg Natural Killer cells and only 5.4 x 10 (4)/kg residual T cells. A melphalan-based, reduced intensity conditioning was used. Despite pretransplant chemotherapy, patients entered transplantation with significant tumor burden. Primary engraftment occurred in 6/6 patients. One patient had secondary graft failure. Hematopoietic recovery was rapid (ANC > 0.5 x 10 (9)/L: 11 days (9-12); independence from platelet substitution: 8 days (7-11)). Four patients had acute GvHD grade II, limited chronic GvHD was observed in 2 patients. No transplant-related mortality and only low toxicity occurred. Four patients died from progression, two patients are alive. Overall median survival time is 6 months (2-11) to date. Analysis of posttransplant NK cell function revealed stable cytotoxic activity against K562 targets, whereas activity against neuroblastoma targets was low. Stimulation with cytokines and use of appropriate antibodies clearly enhanced specific lysis in vitro. In summary, these preliminary results indicate the feasibility and low toxicity even in intensively pre-treated patients with neuroblastomas/sarcomas. This approach may form the basis for posttransplant immunomodulation and other therapeutic strategies. Further experience is warranted to evaluate the method.

Acute Disease↗
PubMedDate not supplied

[The role of interferons in neuroblastoma. 1: Antiproliferative effects].

Antiproliferative effects of interferon alpha, beta and gamma were investigated on several human neuroblastoma cell lines using the soft agar colony forming assay and the MTT-test. Investigations were carried out in order to prove whether there is any relationship between antiproliferative effects, inhibition of N-myc expression and the 2-5A system. Growth of neuroblastoma cells was inhibited by all three kinds of interferons in a concentration-dependent manner, however, rather high concentrations were necessary in some cell lines. Expression of N-myc oncogen was not inhibited by interferon-beta and no relationship between antiproliferative effects and the 2-5A system was observed. A vector containing a small N-myc fragment in antisense direction was constructed and transferred into the interferon insensitive human neuroblastoma cell line LS. After transformation, LS cells became sensitive to interferon beta: Proliferation as well as N-myc expression were inhibited and these processes are most probably associated with activation of the 2-5A system.

2',5'-Oligoadenylate Synthetase↗
PubMedDate not supplied

[The role of interferons in neuroblastoma. 2: Immunomodulatory effects].

The role of Interferon-gamma (IFN-gamma) in the immunotherapy of neuroblastoma was investigated. In vitro experiments showed that IFN-gamma augments the cytotoxicity of Natural Killer (NK) cells and of interleukin 2 (IL-2)-activated NK (LAK) cells against neuroblastoma target cells. Incubation of the neuroblastoma cells with IFN-gamma resulted in an increased susceptibility of these target cells to NK and LAK cells. Additionally, the IFN-gamma-treated neuroblastoma cells showed an increased susceptibility to the antibody-dependent cellular cytotoxicity (ADCC). In patients who have been treated with continuous infusions of IL-2, IL-2-induced secretion of IFN-gamma was detected by measuring the elevation of the 2-5 A synthetase activity in peripheral mononuclear cells or the 2-5 A oligoadenylates in the serum, although IFN-gamma itself was not detectable. From these results we conclude that IFN-gamma may play an important role in the immunotherapy of neuroblastoma in combination with IL-2 and/or with monoclonal antibodies.

Antibody-Dependent Cell Cytotoxicity↗
PubMedDate not supplied

[Indications for autologous bone marrow transplantation in pediatric oncology. Results of the 5th meeting of experts of the Kind-Philipp Foundation, Riesensburg, November 1988].

In November 1988 experts from Europe and the United States of America have met at the Reisensburg near Ulm. The aim of this meeting was to discuss the value of autologous bone marrow transplantation for children with various malignant diseases. The paper summerizes the results of the different sessions. In this way the value of this therapeutic procedure at present time is defined. This is meant as help for those pediatricians who treat children with malignant diseases.

Bone Marrow Transplantation↗
PubMedDate not supplied

Human gammadelta T lymphocytes exert natural and IL-2-induced cytotoxicity to neuroblastoma cells.

Human gammadelta T lymphocytes play an important role in nonadaptive reactions to infection and early tumor defense. This is the first report that freshly isolated, native gammadelta T cells of some healthy donors can kill human neuroblastoma cells to varying degrees. Their killing ability was increased and maintained during expansion and cultivation with interleukin-2 (IL-2; 400 IU/mL) for as long as 30 days (100% specific lysis at an effector-to-target cell (E:T) ratio of 20:1). gammadelta T lymphocytes without this spontaneous killing ability gained a specific cytolytic activity of 81% +/- 10.4% SD after stimulation with IL-2 for 24 hours. gammadelta cells were isolated from peripheral blood by positive enrichment (using a magnetic cell sorting system; purity, 95.2% +/- 3.2% SD, n = 21). High natural cytotoxic activity against human neuroblastoma cell lines (>50% specific lysis at an E:T ratio of 20:1) was exhibited by one of 11 donors, whereas two of 11 showed medium cytotoxicity (30% to 50% specific lysis). Eight of 11 donors showed very slight or no lytic activity against human neuroblastoma cells (<30% specific lysis). gammadelta T cells were also cytotoxic against Daudi (32.7% specific lysis at an E:T ratio of 20:1), Raji (10.3%), Colo 205 (23.1%), A 204 (54%), K 562 (100%), and SK-N-MC (100%) cells. Isolated gammadelta T cells were grown in Iscove modified Dulbecco medium with IL-2 (400 IU/mL). Increased cell proliferation (38.5% to 182%) was induced with phytohemagglutinin, IL-15, Clodronat, OKT3, or various combinations of these. Results of cold target inhibition assays suggest a natural killer-like activity of the gammadelta T-cell killing mechanism. Peptidase or papain render neuroblastoma cells unsusceptible to gammadelta T-cell killing, suggesting the involvement of antigen peptide(s) in the process of neuroblastoma cell killing. Treatment with acid phosphatase reduced specific lysis by 66.5% +/- 34.1% SD, which suggests a binding to phosphorylated neuroblastoma cell-surface structures in the killing mechanism of gammadelta T cells. Heat shock did not affect the extent of neuroblastoma killing by gammadelta cells. Recognition of neuroblastoma cells by gammadelta cytotoxic T lymphocytes is negatively regulated by major histocompatibility complex I receptors. Evidence for natural and inducible cell cytotoxicity of gammadelta T cells against human neuroblastoma cells, easy propagation, purification, and missing alloreactivity in mixed lymphocytes cultures indicates a role for this subpopulation of T lymphocytes in adoptive immunotherapy.

Adult↗
PubMedDate not supplied

Expression analysis of multidrug resistance associated genes in neuroblastomas.

In a series of 40 neuroblastomas we analyzed the relative mRNA levels of the MDR associated genes encoding MDR1/P-glycoprotein (MDR1), multidrug resistance associated protein (MRP), lung cancer resistance related protein (LRP) and topoisomerase IIalpha (TOPO IIalpha) by cDNA-PCR. Cyclin A (CYCA) was included to examine cellular proliferation activity. MYCN gene expression was analyzed as it was recently shown to be associated with enhanced MRP gene expression in neuroblastomas. We found that tumors with MYCN gene amplification exhibit significantly increased MYCN and MRP gene expression levels. Tumors with an allelic loss of the chromosomal 1p region showed significant (P<0.05) lower MDR1 gene expression (MDR1: 50+/-29, n=4) than tumors without (MDR1: 117+/-81, P<0.05, n=36). Moreover, significant positive correlations were found for MYCN/TOPO IIalpha (P<0.0001), MYCN/CYCA (P<0.05), TOPO IIalpha/CYCA (P<0.01), MRP/CYCA (P<0.0001) and MRP/LRP (P<0.05). Our results give evidence that MDR in neuroblastomas might be caused by multiple resistance factors and that a higher proliferation rate of neuroblastoma cells possibly based on altered MYCN gene expression is associated with enhanced MRP, CYCA and TOPO IIalpha gene expression.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMedDate not supplied

Treatment of neuroblastoma with [131I]metaiodobenzylguanidine: long-term results in 25 patients.

From 1984 to 1990 we have treated altogether 25 children with [131I]metaiodobenzylguanidine (131I-MIBG) for a refractory, relapsed or metastasized neuroblastoma. Three children had stage III and 22 children had stage IV of the disease; at diagnosis their ages were between 4 months and 10 years. Children with stage III disease had at diagnosis a median age of 3.0 years and at treatment 3.8 years. After first-line chemotherapy 2 children had achieved a complete remission (CR), while in 1 child the tumor did not respond (NR) to the initial treatment. At the time of 131I-MIBG treatment 2 children had relapsed and in the other one no further response was achievable. The children were treated by a 13.5 +/- 12.9 mCi/kg BW per course with a mean total dose of 280.7 +/- 243.9 mCi. One child achieved CR by 131I-MIBG alone, while in 2 cases no measurable success was observed. All 3 children were treated additionally by surgery, chemotherapy and bone marrow transplantation (BMT). Two children have died but one is alive and in CR. The 22 children with stage IV disease were treated in two different study groups. In group A, 14 children were studied for side-effects and response to 131I-MIBG. All children were pretreated with standard chemotherapy. Five were treated in relapse, 5 in progression and 3 at a refractory state of the disease; only 1 child was in complete remission when being treated with 131I-MIBG. Group A patients were treated with a mean of 2.4 courses, with 10.3 mCi/kg BW for each course.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Iodobenzylguanidine↗
PubMedDate not supplied

Quantitative assessment of mixed hematopoietic chimerism by polymerase chain reaction after allogeneic BMT.

Patients who develop mixed hematopoietic chimerism (MHC) after allogeneic bone marrow transplantation (allo-BMT) might have an increased risk of relapse or graft failure. In order to identify patients with MHC we established a quantitative polymerase chain reaction (PCR) approach to estimate the individual degree of autologous recovery and investigate the dynamics of MHC posttransplant. Therefore standardized mixed chimeric samples were generated in each individual case by mixing pretransplant recipient and donor DNA at a range of percentages. After amplification the samples were analyzed densitometrically and signal intensities were taken as the basis of individual standard curves. Subsequently posttransplant DNA samples were also analyzed, the intensity of the informative signals were compared to the standard curves and autologous recovery was expressed in percentage related to host DNA. We investigated 40 pediatric patients receiving allo-BMT by this method. 10/40 developed MHC during course of the observation period. Each patient with MHC revealed a certain dynamic. This approach might be helpful when deciding on early intervention and additional treatment to prevent graft failure or relapse.

Bone Marrow Transplantation↗
PubMedDate not supplied

Positive selection of CD56+ lymphocytes by magnetic cell sorting.

A new method for the isolation of CD56+ lymphocytes from peripheral mononuclear blood cells is described. Magnetic microbeads conjugated to goat antimouse antiserum in combination with a murine monoclonal anti-CD56 antibody were coated to the CD56+ target cells. CD56+ cells were then isolated with the use of a magnetic cell sorter. The purity of the CD56+ cells was 98.4 +/- 1% (n = 12) with a recovery of the CD56+ lymphocytes of 57.2 +/- 9% (range 48-77%). The natural killer, activity of the CD56+ lymphocytes as well as the interleukin-2-induced proliferative response were not affected by the isolation procedure or the presence of the magnetic microbeads on the CD56+ cells. The described method might be a useful tool for the further characterization of CD56+ cells and their subsets and can easily be upgraded for clinical use in adoptive immunotherapy with CD56+ lymphocytes.

Adult↗