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Biomedical subjects

H Zwierzina

Publications and source records attributed to H Zwierzina.

At least 19 recordsLinked to original sources

Cloning and genomic characterization of LST1: a new gene in the human TNF region.

The leucocyte specific transcript - 1 (LST1) represents the human homolog of the mouse B144 transcript, encoded within the tumor necrosis factor (TNF) region of the human major histocompatibility complex class III interval. The gene is localized about 4 kilobases upstream of the lymphotoxin beta gene. It spans a polymorphic genomic region encompassing the microsatellites TNFd and TNFe in intron 3 and a polymorphic Pvu II restriction site 260 base pairs downstream of the polyadenylation signal. Isolation of a full-length cDNA clone revealed that LST1 codes for IFN-gamma-inducible 800 nt transcripts, which are present in lymphoid tissues, T cells, macrophages, and histiocyte cell lines. The cDNA contains three long open reading frames (ORF) with the most likely ORF encoding a transmembrane protein. Its close linkage to the TNF genes and pattern of expression point toward a possible role for LST1 in the immune response.

Amino Acid Sequence

Clinical importance of P-glycoprotein-related resistance in leukemia and myelodysplastic syndromes--first experience with their reversal.

P-glycoprotein (P-gp) expression in mononuclear bone marrow cells was analyzed in 119 patients, including 60 with chronic myelogenous leukemia (CML), 48 with myelodysplastic syndromes (MDS), and 11 with acute myelogenous leukemia (AML). For P-gp measurement an immunocytological method using monoclonal antibodies C219, 4E3, and MRK 16 and the reverse transcription-polymerase chain reaction technique were applied. According to our results obtained in healthy volunteers using the immunocytological method, the limit for P-gp overexpression was set at > or = 10% P-gp-positive mononuclear bone marrow cells and at > or = 30% P-gp-positive mononuclear peripheral blood cells. All 42 CML patients in chronic phase had normal P-gp expression. P-gp overexpression was demonstrated in four of six patients in accelerated myelogenous blast cell phase and in four of 12 CML-BC patients. Of eight CML patients in blast crisis (BC) with normal P-gp expression, partial remission was achieved in three and minor response in five after prednisone/vindesine therapy. All four of the 12 CML-BC patients with P-gp overexpression did not respond to this therapy. Normal P-gp expression was seen in 41 (85.4%) of 48 untreated MDS patients. While P-gp overexpression did not develop during therapy in any of the myelodysplastic syndrome patients treated with low-dose ara-C alone, four of eight treated with low-dose ara-C plus GM-CSF and four of 11 treated with low-dose ara-C and IL-3 developed P-gp overexpression after therapy. Furthermore, 11 AML patients at primary diagnosis, including five AML patients with P-gp overexpression, who were treated with idarubicin, vepesid, and cytarabine V (ara-C) showed a complete remission. Additionally, one daunorubicin-cytarabine-pretreated refractory AML patient was treated with the oral form of the P-gp modulator drug dexniguldipine and achieved complete remission for a duration of 7 months. Our results suggest that in CML patients in BC, P-gp expression influences outcome after therapy. Further more, studies in a larger series of patients are necessary to prove the efficacy and toxicity of idarubicin/vepesid and cytardbine--or dexniguldipine-containing--therapy in relation to P-gp expression of AML patients.

ATP Binding Cassette Transporter, Subfamily B, Mem

Clinical significance of urinary cyclic guanosine monophosphate in diagnosis of heart failure.

We measured concentrations of guanosine 3',5'-monophosphate (cGMP) in plasma and urine of healthy subjects and patients with congestive heart failure, renal impairment, neoplastic disease, and hepatic cirrhosis. There was no correlation between cGMP concentrations in urine and in plasma. In all patients except those with renal impairment, urinary cGMP concentrations were significantly higher than in healthy persons. Only patients with heart failure or renal impairment showed significantly increased plasma cGMP concentrations. In contrast, cGMP in urine does not relate to the clinically assessed severity of heart failure (New York Heart Association functional classes). Determination of cGMP in plasma results in higher sensitivity and specificity for diagnosing heart failure than measurement of cGMP in urine.

Adult

A randomized phase II study of low-dose cytosine arabinoside (LD-AraC) plus granulocyte-macrophage colony-stimulating factor (rhGM-CSF) in myelodysplastic syndromes (MDS) with a high risk of developing leukemia. EORTC Leukemia Cooperative Group.

In a randomized phase II study, patients with myelodysplastic syndromes (MDS) with 10-30% blasts in the bone marrow and hematopoietic failure were treated with low-dose Ara C (2 x 10 mg/m2 subcutaneously (s.c.) days 1-14) and rhGM-CSF (fully glycosylated, Sandoz/Schering-Plough, 2 x 150 micrograms protein/day s.c.) given either following Ara C (days 15-21) or simultaneously (days 8-14) for 1-5 cycles. 108 patients with a median age of 65 years, range 17-80 years and refractory anemia with an excess of blasts (RAEB, n = 54), RAEB with transformation (RAEBt, n = 50) or with chronic myelomonocytic leukemia (CMML, n = 4) were evaluable. Complete remission was achieved in 15 cases (14%), 11 had a partial response (10%), and 16 a minor response (15%). Stable disease was reached in 35 cases (32%). There were 16 cases of toxic death (15%), progression occurred in 15 patients (14%). No differences existed between the two treatment arms with respect to response and duration of response. Prognostic factors for poor response included the presence of cytogenetic abnormalities and a history of previous blood transfusions. Major adverse events during treatment were hemorrhage (55%), infections (54%), and fever associated with GM-CSF administration (40%). The overall response rate ws 39%, median duration was 12.5 months from start of treatment which allowed responding patients to lead good quality life without further therapy. The question whether the combination is indeed superior to LD-Ara C alone is not settled but will be evaluated in an ongoing clinical trial.

Acute Disease

Practical aspects of cytokine therapy.

Biological therapy with cytokines and growth factors represents a completely new approach in cancer therapy and forces us to adapt our research procedures originally tailored to cytotoxic agents. The lack of reliable predictive in vitro systems or animal models for biological agents and the fact that promising candidates must proceed rapidly to the clinic implies that a drug's therapeutic potential can only be assessed following careful studies in man. Consequently, the effectiveness of clinical trials must be improved by closely relating them to research programs utilizing material from cytokine-treated patients. In clinical practice, patients with low tumor burden may profit most from therapy with immunomodulators, which requires minimally effective doses rather than maximally tolerated dosages. Hemopoiesis can be influenced either by hemopoietic growth factors or by negative regulators, which may prevent stem cell damage during chemotherapy. According to the principles of autocrine growth mechanisms, resting malignant cells may be triggered into cell cycle by their growth factor(s), thus becoming more sensitive to chemotherapy. When discussing the fascinating aspects of the cytokine network, we must be aware that we are only beginning to understand the mechanisms of biological therapy and that close cooperation among preclinical and clinical scientists is required for its rational development.

Animals

Recombinant human interleukin-8 restores function in neutrophils from patients with myelodysplastic syndromes without stimulating myeloid progenitor cells.

Prognosis in myelodysplastic syndrome (MDS) is not only correlated closely with blast cell count in bone marrow and chromosomal abnormalities but also correlated with decreased leucocyte count and function leading to acquisition of lethal infections. Recently, clinical trials in MDS have focused on the application of haemopoietic growth factors such as G-CSF or GM-CSF, which have proven to increase neutrophil count and function. However, these cytokines carry the risk of stimulating the malignant clone, particularly in patients with increased blast cell count. Therefore, investigation of cytokines which are able to stimulate neutrophil function without the potential risk of stimulating haemopoietic progenitor cells may be relevant for MDS. As the stimulatory effect of interleukin-8 on neutrophil function is well known, we investigated whether recombinant human IL-8 is also able to improve the function of neutrophils gained from patients with MDS. Using three different techniques--the E. coli killing assay (8 patients), the production of reactive oxygen as determined by cytochrome c reduction (7 patients) and chemiluminescence (8 patients)--a significant stimulation of neutrophil function at a concentration of 10 nm IL-8 was found in all test systems. No correlation with FAB classification was evident. On the other hand, IL-8 only mildly stimulated growth of myeloid progenitor cells in bone marrow culture of healthy individuals and MDS patients. This minimal stimulation was blocked by a neutralizing antibody directed against GM-CSF, suggesting an indirect effect of IL-8 via secondary GM-CSF release. Thus, IL-8 is able in vitro to repair the functional abnormalities of neutrophils from patients with MDS but has only a marginal influence on myeloid progenitor cells.

Blood Bactericidal Activity

A randomized phase-I/II multicenter study of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy for patients with myelodysplastic syndromes and a relatively low risk of acute leukemia. EORTC Leukemia Cooperative Group.

To assess the effects of GM-CSF in patients with myelodysplasia, a total of 101 patients with refractory anemia (RA), RA with ringed sideroblasts (RARS), and RA with an excess of blasts provided that the percentage of blasts in the bone marrow did not exceed 10% (RAEB) were enrolled in the EORTC Leukemia Cooperative Group study 06885. They were randomized to receive two daily subcutaneous injections of rhGM-CSF (mammalian, glycosylated, Sandoz/Schering-Plough) at a daily dose of either 108 micrograms glycoprotein (group I) or 216 micrograms glycoprotein (group II) for 8 weeks. Response was defined as an increase in Hb (greater than 2.5 g%), neutrophil count (more than 100%), or platelet count (more than 100%) without progression of the disease. After exclusion of 19 patients who did not meet the entry criteria, 82 were evaluated. Fifty-four patients (66%) responded (27 of 42 patients in group I and 27 of 40 in group II). Progressive disease was seen in two patients of group I and in four of group II. Two of the latter developed leukemia. All responses were reflected in the granulocytic series. In two patients platelet numbers also increased. Cytogenetic analysis, successfully performed in 43 cases, showed that 14 of 16 patients with normal karyotypes responded, compared with 14 of 27 patients with abnormal karyotypes (p = 0.008). In some cases GM-CSF was reduced in dose or discontinued prematurely due to side effects so that only 35% of all evaluable patients finished 8 weeks of treatment without a change of dose.

Acute Disease

Treatment of myelodysplastic syndromes (MDS) and high leukaemic risk with low-dose cytosine arabinoside (LD-AraC) plus granulocyte-macrophage colony-stimulating factor (rh GM-CSF). The EORTC Leukaemia Group.

Symptomatic patients with myelodysplastic syndromes (MDS) and 10-30% blasts in the bone marrow were treated with low-dose AraC (2 x 10 mg/m2 subcutaneously (sc) days 1-14) and GM-CSF (fully glycosylated, Sandoz/Schering-Plough, 2 x 150 micrograms protein/day sc) given either subsequently (days 15-21) or simultaneously (days 8-14 and one week rest). Evaluations were carried out after three courses (nine weeks); responding patients could be continued for two further cycles. Eighty-two patients with refractory anaemia and excess of blasts (RAEB), with (RAEBt) or without transformation, were evaluable: 45 RAEB and 37 RAEBt, mean age 64 years (range 17-80 years). A complete remission was achieved in 14 cases (17%), 11 had a good response (13%), and 12 a partial response (15%). Stable disease was found in 21 cases (26%). There were 12 cases of toxic death (15%), progression was noted in eight patients (10%), and death due to disease in three (4%). No difference existed between the two treatment arms with respect to response. Major adverse events during treatment were haemorrhage (25%), infections (23%), and fever with GM-CSF (21%). GM-CSF did not induce leukaemia nor contribute to haemorrhage induced by AraC, but gave rise to an overall response rate of 46% which is high and relatively durable as compared to other treatments in this disease.

Acute Disease

Endogenous serum levels and surface receptor expression of GM-CSF and IL-3 in patients with myelodysplastic syndromes.

The majority of patients suffering from myelodysplastic syndromes (MDS) die of complications due to cytopenia. Clinical trials have demonstrated that in an essential number of MDS patients cytopenia can be ameliorated by exogenously supplied growth factors. We investigated endogenous serum levels of GM-CSF and IL-3 in 15 healthy individuals and 34 patients suffering from MDS. No circulating growth factors were detected in the serum of healthy controls, nor was IL-3 measurable in MDS patients. GM-CSF serum levels, however, were elevated in a significant number of patients (26.5%). Levels did not correlate with FAB classification, leukocyte count or chromosomal abnormalities. No significant differences in GM-CSF or IL-3 receptor expression were detected between healthy individuals and MDS patients. One patient with increased endogenous GM-CSF serum level and normal surface receptor expression responded to exogenously applied GM-CSF. In the light of these results, a functional alteration of growth factor receptors or disturbances of signal transduction pathways must be discussed for MDS.

Adult

Granulocyte-macrophage colony-stimulating factor (GM-CSF) treatment of clozapine-induced agranulocytosis: a case report.

BACKGROUND: Granulocytopenia and agranulocytosis are severe side effects of clozapine therapy. Even if these side effects are detected early and if clozapine is discontinued, patients suffering from agranulocytosis are extremely endangered by infectious diseases for up to 3 to 4 weeks until hematologic recovery. Therefore, any treatment that reduces this critical time span would decrease the risks of clozapine treatment. METHOD: The case of a patient in whom severe agranulocytosis developed after 7 weeks of clozapine treatment is presented. RESULTS: After clozapine discontinuation, treatment with granulocyte-macrophage colony-stimulating factor (GM-CSF), a glycoprotein that has been shown to stimulate the proliferation of precursor cells in the bone marrow and their differentiation into granulocytes and macrophages, was initiated. Under GM-CSF treatment, total granulocyte count rose from 63/cu mm to a value greater than 1500/cu mm within 5 days without complications or major side effects. CONCLUSION: This case report suggests that treatment with GM-CSF may lower the risks associated with clozapine-induced agranulocytosis and therefore may indirectly improve the safety of clozapine therapy.

Adult

Epidermal Langerhans cells in myelodysplastic syndromes are abnormal.

The myelodysplastic syndromes (MDS) represent clonal disorders of the hematopoietic stem cell that are associated with quantitative and qualitative disturbances of the peripheral blood cells and a high risk for the transition to overt leukemia. As epidermal Langerhans cells (LC) are bone-marrow-derived cells, we were interested to see whether they are altered in patients with MDS. Epidermal sheets were prepared from biopsies taken from the thighs of nine patients with MDS and five control persons and processed for immunoperoxidase staining of CD1a antigens. The density and morphology of CD1a+ cells (i.e., LC) was evaluated by visual assessment as well as automatic image analysis. The density of LC was reduced in seven of nine patients (range, 30-75% of normal), whereas the morphology of LC appeared to be altered in all MDS patients in that the LC displayed large and bizarre cell bodies with only a few and often abnormally long dendrites. The HLA-DR expression by LC was not altered, as shown by double immunofluorescence staining of CD1a and HLA-DR antigens. Ultrastructurally, LC again appeared enlarged and often presented with bizarre nuclei, yet displayed no other abnormalities. Our findings suggest that LC are abnormal in MDS and might even indicate a more wide-spread involvement of the dendritic cell lineage in this syndrome.

Humans

Detection of soluble IL-2 receptor in the serum of patients with myelodysplastic syndromes: induction under therapy with GM-CSF.

Sera of 15 healthy controls and 33 patients suffering from myelodysplastic syndromes (MDS) were investigated for soluble interleukin-2 receptor (sIL-2R) expression with a cell-free enzyme-linked immunosorbent assay (ELISA) system (T-Cell Sciences; Cambridge, U.S.A.). The upper limit of the assay is indicated with 477 U/ml. According to the FAB classification eight refractory anaemia (RA), 15 refractory anaemia with excess of blasts (RAEB), five refractory anaemia with excess blasts in transformation (RAEBt) and five chronic myelomonocytic leukaemia (CMML) were examined. None of the patients had reported infectious episodes or been under treatment with cytotoxic agents and/or cytokines within the previous 3 months. Significant differences in sIL-2R levels between RA (median 368 U/ml). RAEB (median 675 U/ml) and RAEBt (median 971 U/ml) and between RA and CMML (median 723 U/ml) were detected. Six patients, who had been under treatment with rhGM-CSF for at least 2 weeks, demonstrated a three- to sevenfold increase of sIL-2R expression compared to pretreatment levels. In kinetic evaluation of serum samples for 24 h, the increase of sIL-2R expression begins within 4 h after subcutaneous application of GM-CSF and reaches its maximum after 12 h. Our data cannot suggest whether increased sIL-2R expression is a primary event due to involvement of lymphocytes in the malignant clone or whether it results from secondary alteration of the cytokine network. Application of GM-CSF in MDS may result in improvement of altered lymphocyte function. As GM-CSF induces sIL-2R expression, a down regulation of the immune response caused by neutralization of free IL-2 cannot be excluded.

Adult

[In vitro effects and possible clinical relevance of interleukin 3].

Cytokines are mainly produced by monocytes and lymphocytes and influence a broad spectrum of physiological processes within the hematopoietic and the immune system. Clinical trials have mainly been initiated with a subgroup of cytokines namely the hematopoietic growth factors. Interleukin 3 (IL-3) was recently introduced into phase I and II trials. This factor was also termed "multipoietin" because of its ability to stimulate in vitro the hematopoietic stem cell and thus all three hematopoietic cell lines. The latest in vivo data, however, demonstrate that IL-3 stimulates leukopoiesis and megakaryopoieis with only marginal effects on erythropoiesis. In large clinical trials the therapeutic effect of this factor is investigated in patients with myelodysplastic syndromes. Further indications will be other primary bone marrow failures and aplasia caused by bone marrow transplantation, aggressive chemotherapy and radiation. Potential applications offered by combinations with other cytokines can hardly be foreseen.

Animals

[Hematopoietic growth factors].

Hematopoietic growth factors represent a subgroup of the cytokines and are also called colony-stimulating factors (CSFs) because of their effects in bone marrow culture. These glycoproteins are produced by a large number of cells and serve to transmit signals within the hematopoietic and the immune system either by themselves or by inducing the production and the release of other cytokines. As their genes have been cloned by molecular biology in the last year, these "recombinant" factors can be produced in large amounts for clinical trials. Cytokines make possible completely new therapy concepts by enabling medicine both to intervene in and modulate the body's own physiological processes. Therapy studies conducted with hematopoietic growth factors to date are encouraging and mostly demonstrate only tolerable dose-dependent side effects. In contrast to the maximal tolerable dose usually applied for cytotoxic therapy regimens, this "biological therapy" aims to a minimal effective dose, known e.g. from interferon. The following article will attempt to provide an insight into the first results of clinical trials and in future possibilities in the clinical application of these factors.

Animals