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Biomedical subjects

A Lindemann

Publications and source records attributed to A Lindemann.

At least 109 records · Page 6Linked to original sources
PubMed1990

Differential regulation of interleukin-6 expression in human fibroblasts by tumor necrosis factor-alpha and lymphotoxin.

The treatment of human diploid fibroblasts with tumor necrosis factor (TNF)-alpha and with lymphotoxin (LT) is associated with induction of interleukin-6 (IL-6) transcripts with TNF-alpha being 10-fold more potent than LT. Here we report on the TNF-alpha/LT-induced signaling mechanisms responsible for the regulation of IL-6 gene expression in these cells. Run-on assays demonstrated that both TNF-alpha and LT increase IL-6 mRNA levels by transcriptional activation of this gene. Stability studies of IL-6 transcripts in fibroblasts showed that TNF-alpha delayed IL-6 mRNA decay but not LT. The induction of IL-6 transcripts by TNF-alpha and LT was not inhibited by the isoquinoline sulfonamide derivative H7. Similarly, depletion of protein kinase C (PKC) by 12-O-tetradecanoyl-phorbol 13-acetate (TPA) did not change the ability of TNF-alpha and LT to induce IL-6 transcripts, demonstrating that stimulation by these agents may not be mediated by activation of PKC. Stimulation of IL-6 transcripts in fibroblasts did also not require new protein synthesis as exposure to the protein synthesis inhibitor cycloheximide (CHX) enhanced accumulation of IL-6 mRNA in the presence or absence of TNF-alpha or LT.

Cells, Cultured↗
PubMed1990

Effects of recombinant human interleukin-3 in patients with normal hematopoiesis and in patients with bone marrow failure.

In a phase I/II study, 19 patients with advanced tumors but normal hematopoiesis and nine patients with bone marrow failure and prolonged severe cytopenias were treated with recombinant human interleukin-3 (rhIL-3) to assess the toxicity and biological effects of this multipotential hematopoietic growth factor. Doses ranging from 30 micrograms/m2 to 500 micrograms/m2 were administered as subcutaneous bolus injection daily for 15 days. A dose-dependent increase in platelet counts ranging from 1.3-fold at 60 micrograms/m2 to 1.9-fold at 250 micrograms/m2 was induced by rhIL-3 in 15 of 18 evaluable patients with normal hematopoiesis. An increase in reticulocyte counts was observed in 14 patients. The blood leukocyte counts dose dependently increased 1.4- to 3.0-fold. In patients with bone marrow failure, platelet counts increased by a mean of sixfold (range, 1.3-fold to 14.3-fold) in five of eight evaluable patients. Reticulocyte counts increased 4.4-fold in six patients, and neutrophil counts increased by a mean of 3.1-fold in all eight patients. Platelet transfusions could be discontinued after treatment with rhIL-3 in two of three transfusion-dependent patients. Only mild side effects, mainly fever, headache, and flushing, were observed. These results indicate that rhIL-3 functions as a multilineage hematopoietin in vivo in patients with normal bone marrow function and in patients with secondary bone marrow failure.

Adult↗
PubMed1990

Effects of recombinant human interleukin-3 in patients with myelodysplastic syndromes.

In a phase I-II study, nine patients with myelodysplastic syndromes and concomitant severe transfusion-dependent cytopenias were treated with recombinant human interleukin-3 (rhIL-3) to improve hematopoietic function. Doses of rhIL-3 ranged from 250 micrograms/m2 to 500 micrograms/m2 and were given as daily subcutaneous bolus injections for 15 days. Blood leucocyte counts increased 1.3- to 3.6-fold in all nine patients, including neutrophils, eosinophils, lymphocytes, basophils, and monocytes. The mean absolute neutrophil counts increased from 1,350/microL (range, 150 to 2,420) to 2,660/microL (range, 300 to 9,380) (P less than .05) immediately after the end of rhIL-3 therapy and to a maximum count of 4,096/microL (range, 350 to 10,820) (P less than .01). Platelet responses were seen in two of four profoundly thrombocytopenic patients, resulting in discontinuation of platelet transfusion. The requirements for red blood cell transfusion temporarily improved in one patient. Stimulation of plasma cells was evident by a significant increase in serum IgM and IgA levels. Mild side effects (fever, headache, local erythema, and bone pain) were observed in some patients, while transient thrombocytopenia developed in two patients. Disease progression with an increase in blast cells was seen in one patient. These results suggest that rhIL-3 is effective in stimulating hematopoiesis of all lineages in patients with myelodysplastic syndromes and may produce at least short-term hematologic improvement.

Adult↗
PubMed1990

Inducible production of interleukin-6 by human polymorphonuclear neutrophils: role of granulocyte-macrophage colony-stimulating factor and tumor necrosis factor-alpha.

The recent demonstration of the ability of human polymorphonuclear neutrophils (PMN) to secrete various cytokines in response to the granulocyte activator granulocyte-macrophage colony-stimulating factor (GM-CSF) but not to other cytokines, has led to the identification of PMN as biosynthetically active cells. In this study we have investigated the ability of PMN to secrete interleukin-6 (IL-6), a molecule known to be involved in inflammatory reactions. Using RNA blotting analysis and bioassays, we show that PMN could be induced to synthesize transcripts specific for IL-6, indistinguishable in size from IL-6 mRNA produced by activated human macrophages. Consequently, PMN released IL-6-like activity into their culture supernatants that could be neutralized by monospecific anti-IL-6 antibody. Interleukin-6 secretion by PMN, however, required previous stimulation with GM-CSF or tumor necrosis factor-alpha (TNF-alpha), whereas other cytokines, including interleukin-3 (IL-3), granulocyte-CSF (G-CSF), macrophage-CSF (M-CSF), interferon gamma (IFN-gamma), and lymphotoxin (LT), failed to induce IL-6 mRNA accumulation and protein secretion by PMN. Similar to GM-CSF and TNF-alpha, other compounds, including the inhibitor of protein synthesis cyclohexemide (CHX), endotoxin (Escherichia coli-derived lipopolysaccharide), and phorbol myristate acetate (PMA) (but not the chemoattractant N-formyl-methionyl-leucyl-phenylalanine [FMLP]), induced detectable levels of IL-6 transcripts in PMN.

Blotting, Northern↗
PubMed1990

Synthesis of granulocyte colony-stimulating factor and its requirement for terminal divisions in chronic myelogenous leukemia.

In this paper we demonstrate that maturing neoplastic cells from patients with chronic myelogenous leukemia (CML) constitutively produce G-CSF and are also receptive for this molecule. G-CSF functions as an autocrine growth factor in stable phase CML, and thus is responsible for divisions of maturing leukemic cells leading to an expansion of the compartment of mature cells. This observation is well in line with in vivo features of CML in stable phase, i.e., the hyperplasia of the mature granulocyte compartment. In acute blastic phase of CML expression of the G-CSF gene seems to be less common and not related to autonomous blast growth.

Antigens, CD↗
PubMed1990

Cytokine-stimulation of prostaglandin synthesis from endogenous and exogenous arachidonic acids in polymorphonuclear leukocytes involving activation and new synthesis of cyclooxygenase.

Peripheral blood-derived human polymorphonuclear leukocytes (PMNL) can be induced to synthesize prostaglandin E2 (PGE2) from endogenous and exogenous arachidonic acid (AA) when exposed to agents such as human recombinant (hr) granulocyte-macrophage (GM) colony-stimulating factor (CSF), hr tumor necrosis factor-alpha, hr granulocyte (G)-CSF, lipopolysaccharide and the chemoattractant N-formyl-methionyl-leucyl-phenylalanine. Treatment of PMNL with hr macrophage (M)-CSF and interleukin 3, however, did not result in detectable PGE2 synthesis. Cytokines stimulated PGE2 production during two distinct time intervals, an early peak of PGE2 that was detectable at 20 min and a late one detectable after 4 h. Inhibition of protein synthesis by cycloheximide (CHX) had virtually no effect on the early increase of PGE2 but prevented the late increase. Late addition of CHX to cultures after stimulation with hr GM-CSF at 4 h resulted in decline of PGE2 synthesis from exogenous arachidonic acid. Treatment of PMNL with GM-CSF had direct effects on cyclooxygenase (COx). PMNL depleted from COx by acetyl salicylic acid (ASA) recovered to synthesize PGE2 following exposure to GM-CSF. Recovery from COx inhibition by ASA could be prevented by CHX.

Arachidonic Acid↗
PubMed1990

Effect of granulocyte-macrophage colony-stimulating factor on neutropenia and related morbidity induced by myelotoxic chemotherapy.

A phase Ib/II clinical study was undertaken to assess the efficacy of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) to attenuate neutropenia and associated morbidity caused by high-dose anticancer chemotherapy administered in the presence or absence of autologous bone marrow support. We treated 22 patients with various solid tumors and lymphoid neoplasias with a single daily subcutaneous dose of GM-CSF (250 micrograms/m2) 48 h after a second cycle of highly myelotoxic chemotherapy for a period of 10 days and compared intraindividually neutropenia-related clinical and laboratory variables with data obtained from the same patients having previously received a first neutropenia-inducing cycle of identical chemotherapy in the absence of GM-CSF. We show that GM-CSF is active in neutropenic patients by significantly increasing the neutrophil nadir, reducing the time of relevant neutropenia, and reducing the duration of the patient's hospital stay and necessity for parenteral antibiotics. No significant toxicity was encountered with subcutaneous GM-CSF treatment.

Agranulocytosis↗
PubMed1990

MACOP-B chemotherapy for the treatment of high grade and intermediate grade non Hodgkin's lymphoma.

Between Nov. 1985 and Nov. 1988, sixty-three patients with high grade malignant (hg) and intermediate grade malignant (img) Non Hodgkin's Lymphoma (NHL) were treated with MACOP-B (methotrexate, doxorubicin, cyclophosphamide, vincristine, prednisone and bleomycin). Thirty-seven patients received MACOP-B as an upfront treatment modality, whereas twenty-six patients had relapsed disease and received MACOP-B as a salvage protocol. Four weeks after termination of therapy, 75% of patients with de novo NHL and 72% of the patients with relapsed NHL were in complete remission (CR). In the group of newly diagnosed NHL, 22% achieved partial remission (PR) and 3% no change (NC), whereas in the group with relapsed disease 14% had PR and 14% had progressive disease (PD). At a medium follow-up of 12 months (range 1 month to 33 months), 74% of patients with de novo NHL continued to be in CR whereas the continuous CR rate in patients with relapsed disease was 35%. Overall survival after 30 months of observation for the patient group with de novo NHL was 75% and 40% for patients with relapsed NHL. The mean duration for completion of the projected 12 chemotherapy cycles, given in weekly intervals, was 12.9 and 13.5 weeks in upfront or salvage therapy, respectively. With low incidence of major toxicities, application of drugs on an outpatient basis, and high efficacy, MACOP-B shows substantial advantages for therapy of de novo and relapsed NHL.

Adult↗
PubMed1990

Erythropoietin prevents chemotherapy-induced anemia: case report.

A thirty-seven year old male patient with heavily pretreated metastatic testicular carcinoma received escalating doses of recombinant human erythropoietin (EPO) before and throughout chemotherapy. Whereas previous chemotherapy regimens repeatedly caused anemic situations in this patient (hemoglobin (HB) 7.0 g/dl requiring multiple transfusions of red blood cells), EPO given as an i.v. bolus injection at escalating doses of 150 to 300 U/kg body weight (BW) twice/week, starting two weeks prior to the identical myelosuppressive treatment protocol, maintained HB at levels above 8.8 g/dl and thus obviated the need for erythrocyte transfusion. EPO was discontinued after 9 weeks of administration when the patient had achieved a hematocrit (HCT) of 41.1% and a HB of 12.7 g/dl. However, erythropoiesis continued to recover for the next 7 weeks reaching a HCT of 42.4% and a HB of 14.3 g/dl, although the next identical chemotherapy cycle had been given within this period. Along with the rise in HB, ferrokinetics changed significantly as measured by serum ferritin, which was reduced to one third at the end of EPO therapy after only 9 weeks (from 979 ng/ml to 320 ng/ml). No side effects due to EPO administration occurred. These data provide first evidence for efficacy of EPO in chemotherapy-induced anemia and may open new avenues for its clinical application.

Adult↗
PubMed1990

Interferon alfa-2c in chronic myelogenous leukemia (CML): hematologic, cytogenetic and molecular-genetic response of patients with chronic phase CML previously resistant to therapy with interferon gamma.

Alpha- and gamma-interferons have been shown to actively suppress hematopoiesis in patients in the chronic phase of chronic myelogenous leukemia in vitro and in vivo. Since both interferons act through different receptors on their hematopoietic target cells, they are expected to be capable of independently inhibiting abnormal blood cell development in patients with chronic myelogenous leukemia. We have utilized recombinant human interferon alfa-2c to treat 11 patients with Philadelphia chromosome positive chronic myelogenous leukemia in chronic phase, who were resistant to previous interferon gamma therapy. Ten of the patients were evaluable for hematologic, cytogenetic and molecular-genetic response following interferon alfa-2c therapy for 6 to 30 months. In 5 patients, IFN alfa-2c treatment failed due to lack of hematologic response. A complete hematologic or partial hematologic response was achieved in the remaining 5 patients. Three of these experienced cytogenetic improvement with reappearence of 100% diploid hematopoietic cells and disappearence of c-abl/bcr rearrangement in one patient. In two patients interferon alfa-2c did not prevent transformation of the disease into an accelerated state or blast crisis, respectively. We conclude that recombinant human interferon alfa-2c may also control hematopoiesis in interferon-gamma resistant chronic myelogenous leukemia patients, although the long-term response will need to be elucidated in further studies.

Adult↗
PubMed1990

Effect of granulocyte-macrophage colony-stimulating factor on neutropenia and related morbidity induced by myelotoxic chemotherapy.

PURPOSE: A phase Ib/II clinical study was undertaken to assess the efficacy of recombinant human (rh) granulocyte-macrophage colony-stimulating (GM-CSF) factor in attenuating neutropenia and associated morbidity caused by high-dose anticancer chemotherapy administered in the presence or absence of autologous bone marrow support. PATIENTS AND METHODS: Twenty-two patients with various solid tumors and lymphoid neoplasias were treated with a single daily subcutaneous dose of rh GM-CSF (250 micrograms/m2) 48 hours after receiving a second cycle of highly myelotoxic chemotherapy for a period of 10 days. Within-subject comparisons on neutropenia-related clinical and laboratory variables were made with data obtained from the same patients after they received the first neutropenia-inducing cycle of identical chemotherapy in the absence of GM-CSF. RESULTS: GM-CSF was active in neutropenic patients because it significantly increased the neutrophilic nadir, reduced the time of relevant neutropenia, and reduced the duration of a patient's hospital stay and the necessity for parenteral antibiotics. No significant toxicity was encountered with subcutaneous GM-CSF treatment. CONCLUSION: Although GM-CSF was shown to significantly reduce chemotherapy-associated morbidity in patients receiving myelotoxic cancer chemotherapy, additional studies are needed to assess whether the use of GM-CSF in anticancer chemotherapy will allow an increase in the dosage level, leading to improved response rates and survival among cancer patients.

Adolescent↗
PubMed1990

Interleukin-4 regulates mRNA accumulation of macrophage-colony stimulating factor by fibroblasts: synergism with interleukin-1 beta.

We demonstrate that macrophage-colony stimulating factor (M-CSF) is expressed in human fibroblasts at the mRNA and protein level. Following activation with both interleukin (IL)-1 beta and IL-4, fibroblasts synthesized M-CSF transcripts detectable by Northern blot analysis with peak expression occurring at 8 h and 12 h, respectively. Exposure of fibroblasts to both cytokines resulted in M-CSF protein release at 60 h of c. 500 U/ml (for IL-1 beta) and 1000 U/ml (for IL-4), relative to a control preparation of recombinant human M-CSF in a murine bone marrow colony assay. Both interleukins synergized to enhance M-CSF mRNA accumulation and their ability to induce M-CSF transcripts could be abolished by treatment with specific neutralizing antibodies. These observations provide support for the idea that fibroblasts may control monocyte/macrophage development and function, and that IL-1 beta and IL-4 are involved in the regulation of this process.

Blotting, Northern↗
PubMed1990

Erythropoietin for the treatment of anemia of malignancy associated with neoplastic bone marrow infiltration.

This clinical trial was performed to study the effects of intravenously (IV) administered recombinant human (rh) erythropoietin (EPO) at escalating doses (150, 300, and 450 U/kg, administered as an IV bolus injection, twice weekly, for 6, 4, and 4 weeks, respectively) in five patients with low-grade non-Hodgkin's lymphoma (Ig NHL) and bone marrow involvement and one patient with multiple myeloma (MM). All patients were anemic due to underlying disease. None of the patients had a history of bleeding, hemolysis, renal insufficiency, or other disorders causing anemia in addition to bone marrow infiltrating malignancy. Endogenous EPO serum levels were significantly increased in all patients (74 to 202 mU/mL). Five patients (one MM, four small-cell lymphocytic [SCLC] NHL) showed a dramatic increase of hemoglobin (Hb), hematocrit (Hk) and RBC count becoming obvious on the second EPO dose level. Initial ferritin serum values, which were high mostly due to polytransfusion, were significantly reduced in responding patients. Erythropoiesis of one patient with extensive follicular mixed (fm) NHL did not respond to EPO treatment. Platelet (PLT) count increase (greater than 75% above starting levels) during and following EPO therapy was observed in one patient with MM. Adverse events due to EPO therapy have not been recorded. These findings point out a previously unrecognized capacity of EPO given at pharmacologic doses to stimulate erythropoiesis in patients with anemia due to bone marrow infiltration by neoplastic lymphocytes in spite of enhanced endogenous EPO expression.

Aged↗
PubMed1990

Gamma-interferon interrupts growth stimulation in chronic myelogenous leukemia established by endogenous granulocyte colony-stimulating factor.

We have previously shown that maturing neoplastic cells from patients with stable phase chronic myelogenous leukemia (SP CML) constitutively produce granulocyte colony-stimulating factor (G-CSF) and are also receptive for this molecule. G-CSF functions as an endogenous growth factor in SP CML, and thus is responsible for divisions in maturing leukemic cells leading to an expansion of the compartment of mature cells. In the investigations to be reported below, the effects of various hematopoietic inhibitor molecules on the expression of the G-CSF gene by SP CML bone marrow cells enriched for promyelocytes/myelocytes were examined at the mRNA and protein level. We show that exposure of SP CML bone marrow promyelocytes/myelocytes to recombinant human (rh) interferon (IFN)-gamma but not to rh IFN-alpha, rh tumor necrosis factor (TNF)-alpha, and rh lymphotoxin (LT) leads to downregulation of G-CSF expression and interruption of the G-CSF-mediated endogenous growth stimulation. The action of G-CSF takes place at the posttranscriptional level and involves an acceleration of decay of steady-state levels of G-CSF transcripts in the malignant cell population.

Bone Marrow↗
PubMed1990

[In vitro and in vivo effects of recombinant human interleukin-3 on hematopoietic progenitor cells].

As part of a phase I/II clinical trial with recombinant human Interleukin-3 (rhIL-3), bone marrow and peripheral blood cells from patients treated with rhIL-3 were assessed in vitro for effects on the cycling status and frequencies of erythroid, myelomonocytic and multilineage progenitor cells. Treatment with rhIL-3 induced a pronounced increase in S-phase rate of BFU-E, CFU-GEMM and day 14 CFU-GM. Circulating CFU-GEMM and day 14 CFU-GM were increased on day 7 of therapy whereas circulating BFU-E were reduced in the majority of patients. After i.v. bolus injection of IL-3 an acute effect on the peripheral blood count with neutrophilia and, after an initial nadir, monocytosis was observed. IL-6 serum-levels increased in 5 out of 14 patients after IL-3 administration with concomitant side effects in 2 patients in whom IL-6 levels increased above 75 pg/ml. In the majority of the patients a stimulation of peripheral leukocytes and platelets was observed during the 15 day treatment course. In conclusion rhIL-3 induces a multilineage response in vivo by stimulating proliferation of hemopoietic progenitor cells with a resulting elevation in peripheral blood counts.

Bone Marrow↗
PubMed1990

Granulocyte-macrophage colony-stimulating factor and interleukin-3 induce surface expression of interleukin-2 receptor p55-chain and CD4 by human eosinophils.

In this report it is shown by immunofluorescence analysis, biochemical analysis and mRNA hybridization that human eosinophils express surface CD4 and interleukin-2 receptor (IL-2R) (CD25) when exposed to eosinophil activators granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-3. Although the functional role of eosinophil CD4/CD25 expression has to be elucidated, it will be of interest in further studies to investigate whether in vivo induction of these molecules occurs in association with certain disease processes such as the hypereosinophilic syndrome or in immunological responses during allergic and helminthic parasitic diseases.

Blotting, Northern↗