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L Bergmann

Publications and source records attributed to L Bergmann.

At least 73 records · Page 4Linked to original sources
PubMed1997

The Wilms' tumor gene is expressed in a subset of CD34+ progenitors and downregulated early in the course of differentiation in vitro.

The Wilms' tumor gene (wt1) is strongly expressed in malignant blasts of acute myeloid leukemia (AML) in approximately 80% of all cases. However, the role of wt1 expression in non malignant hematopoietic cells remains unclear. To characterize the expression of wt1 in differentiating hematopoietic progenitors, we isolated and cultured CD34+ progenitor cells from four healthy bone marrow donors with stem cell factor (SCF) and granulocyte colony stimulating-factor (G-CSF) to induce differentiation into granulocytes. Four different cultures were carried out for 12 days. During culture, wt1 mRNA expression was analyzed by defining its ratio relative to beta-actin using reverse transcriptase polymerase chain reaction (RT-PCR). To monitor the stage of differentiation, expression of cell surface markers and peroxidase was analyzed daily. The initial purity of CD34+ cells ranged between 80% and 90%; after 12 days, the frequency of neutrophil bands and segmented neutrophils was approximately 60%. Using RT-PCR to determine the ratio of wt1 to beta-actin expression, we reproducibly detected maximum expression of wt1 mRNA at day 0 in two cultures and at day 1 in two other CD34+ cell cultures; at both these time points nearly all cells fulfilled the morphological and immunephenotypical criteria of early hematopoietic blast cells. Wt1 expression dropped rapidly at day 1 and 2, respectively, in these two pairs of cultures, and was accompanied by an increase of cells expressing CD33 surface antigen. Our data suggest that wt1 expression is restricted to a subset of CD34+ progenitors and downregulated in later stages of differentiation in vitro.

Antigens, CD34↗
PubMed1996

[Autoimmune diseases of the peripheral cornea. Immunopathology, clinical aspects and therapy].

Noninfectious ulceration of the peripheral cornea remains a major diagnostic and therapeutic challenge. The pathogenesis in most of these disorders is unclear, however, on the basis of systemic connective tissue diseases, autoimmune mechanisms are most likely involved. The peripheral cornea has distinct morphological and immunological characteristics that predispose for inflammatory reactions. Major differences exist regarding humoral and cellular components of the immune system. In the peripheral cornea there is more high-molecular IgM and initial complement component C1 than in the central cornea and may predispose for immune complex formation. The close contact to the conjunctival vasculature provides the basis necessary to generate an immune response. Langerhans cells and macrophages as important antigen presenting and processing cells are present in higher number in the peripheral cornea. Autoimmune diseases that affect the peripheral cornea include collagen vascular diseases and Mooren's ulcer. Although this association is obvious in advanced rheumatoid arthritis more subtle forms of polyarteritis nodosa or systemic lupus erythematosus require careful medical evaluation and workup. Ocular manifestations may present as the initial clinical signs and require careful workup in these potentially lethal disorders.

Antigen-Presenting Cells↗
PubMed1996

Itraconazole for prophylaxis of systemic mycoses in neutropenic patients with haematological malignancies.

The efficacy of oral itraconazole 2 x 200 mg capsules daily for prevention of systemic mycoses was investigated in granulocytopenic patients with haematological malignancies. Of 241 patients, 197 were evaluable for prophylactic efficacy, and 214 for adverse events. Patients with similar characteristics receiving oral amphotericin B as antifungal prophylaxis, observed over 15 months before introduction of itraconazole, served as control group (n = 223). With itraconazole prophylaxis, 13 cases of aspergillosis (9 proven, 1 probable, 3 possible; 7%) and no systemic yeast infection occurred, compared with 14 episodes of aspergillosis (9 proven, 2 probable, 3 possible; 6%) and 3 proven systemic yeast infections (Candida albicans, Candida norvegensis, Trichosporon beigelii) in the historical group. Adverse events were observed in 13% of evaluable patients receiving itraconazole. In four patients with acute lymphoblastic leukaemia receiving itraconazole and vincristine simultaneously, severe vinca alkaloid-induced neurotoxicity occurred. Plasma concentrations of itraconazole and hydroxyitraconazole were measured in 64 patients. After eight days of itraconazole the median drug concentration was adequate (700 ng/mL), but there was a marked individual variation (229-2861 ng/mL). In comparison with a historical group, antifungal prophylaxis with itraconazole reduced the incidence of systemic yeast infections, but the frequency of aspergillosis was similar. However, a general increasing incidence of aspergillus infections at our hospital over the last four years should be considered in the assessment of study results.

Administration, Oral↗
PubMed1996

Peripheral T-cell lymphomas respond well to vincristine, adriamycin, cyclophosphamide, prednisone and etoposide (VACPE) and have a similar outcome as high-grade B-cell lymphomas.

Peripheral T-cell lymphomas (PTCL) represent a heterogeneous group of T-cell malignancies including subentities with favourable (large cell anaplastic) or unfavourable (pleomorphic) prognosis. The clinical outcome of PTCL has been controversially discussed, but a worse prognosis than high-grade B-cell Non-Hodgkin's lymphomas (NHL) has been postulated by most authors. In this report we summarize the results of a prospective comparative study investigating the therapy outcome of 27 patients (pts) with PTCL and 55 pts. with high grade B-cell NHL and give an overview of therapy studies in PTCL. The histological subtypes were 14 pleomorphic, 8 large-cell anaplastic (Ki-1+), 2 angioimmunoblastic (AILD) and 3 other PTCL. In three patients the PTCL was associated with non-tropical sprue (11%). Nineteen patients presented with an advanced stage of disease (stage III and IV, 70%), 17 (63%) pts. had B-symptoms. The patients were treated with vincristine 2 mg d1, adriamycin 25 mg/m2 d1-3, cyclophosphamide 800 mg/m2 d1, prednisone 60 mg/m2 d1-7 and etoposide 120 mg/m2 d1-3 (VACPE). In 77% of pts. with PTCL and 84% of patients with high-grade B-cell NHL a complete remission (CR) was achieved. 75% of the complete responders with PTCL and 70% with B-NHL are still in ongoing CR. The subgroup of large-cell anaplastic attained a CR in 88%. The median observation time is 44 months (1(+)-77+). The probability of 1-, 3- and 5-year overall and disease-free survival for the T-cell group were 76%, 54%, 48% and 76%, 62%, 62%, respectively according to Kaplan-Meier. There was no significant difference regarding the remission rate, the overall-, event-free or disease-free survival compared to high-grade B-cell lymphomas. In conclusion, the VACPE regimen is an effective and feasible regimen in the management of PTCL achieving complete remissions in a large proportion of patients.

Adolescent↗
PubMed1996

Specular microscopy: from speculative to spectacular microscopy.

The evolution of confocal microscopy for in vivo qualitative analysis of the cornea seems to follow a path similar to that followed by specular microscopy after its reintroduction almost 20 years ago. The purpose of this report is to present the evolution of our own research data, starting with speculation concerning the attribution of morphological features and finishing with cell-to-cell correlation with special techniques. We present representative clinical but mainly experimental data from relocation studies using flat preparation, especially developed sequential vital staining techniques, and scanning electron microscopy as compared with specular microscopy. Starting from speculative attribution of the observed morphological features, we were capable of classifying morphological data on the endothelium and the surrounding structures into preendothelial, endothelial, retroendothelial, and non-endothelial features. Specular microscopy allows the detailed study of cellular and even intracellular structures and is probably one of the most spectacular ways of doing noninvasive in vivo microscopy in humans.

Endothelium, Corneal↗
PubMed1995

Lactate dehydrogenase-release assay: a reliable, nonradioactive technique for analysis of cytotoxic lymphocyte-mediated lytic activity against blasts from acute myelocytic leukemia.

Treatment of patients in remission of acute myelocytic leukemia using immunotherapy with interleukin 2 is a new approach to prolonging remission duration in this disease. As an important mechanism for the pathophysiology of eradication of residual myelocytic blast populations, activation of cytotoxic effector lymphocytes has frequently been discussed. However, the associated immunological research has been complicated to some extent, because in conventional chromium 51-release assays, blast cells frequently fail to incorporate sufficient amounts of 51Cr and/or spontaneously release high amounts of 51Cr. Recently, we established a culture system which promotes the outgrowth of cytotoxic T lymphocytes in bone marrow-derived mononuclear cells cultured in IL-2. To study cytotoxicity and the responsible mechanisms of the obtained T-cell lines and clones, we modified a previously described cytotoxicity assay, based on the release of lactate dehydrogenase (LDH-release assay) for use in cryopreserved blasts obtained from the bone marrow of patients with acute myelocytic leukemia. Using this assay, we were able to detect cytotoxicity of IL-2-activated peripheral blood lymphocytes from three healthy controls against a number of blast samples obtained from the bone marrow of patients with AML (up to more than 40% lysis at an effector target cell ratio of 20:1). However, a minority of AML blasts seem to be resistant to lysis by IL-2-activated lymphocytes. In bone marrow-derived T-cell lines from patients with AML we detected lytic activity against autologous blasts in three of seven cases tested by LDH release, ranging from 29 to 63% at an effector target ratio of 10:1. Additionally, T-cell clones with different phenotypes were established which were able to mediate cytotoxicity against autologous blast cells. Thus, cytotoxicity against freshly isolated blasts from patients with acute myelocytic leukemia can be analyzed reliably, reproducibly, and without the use of isotopes by the LDH-release assay.

Blast Crisis↗
PubMed1995

Bone marrow-derived T-cell clones obtained from untreated acute myelocytic leukemia exhibit blast directed autologous cytotoxicity.

The eradication of minimal residual blast populations by activation of autologous cytotoxic cells with interleukin 2 (IL-2) is a new promising tool in the treatment of acute myelocytic leukemia (AML). However, the immunological effector cells are not yet clearly defined. The present study was designed to investigate the presence of cytotoxic precursor cells in active AML and to identify phenotypical and functional characteristics of autologous anti-leukemic cytotoxic effector cells. For this purpose, mononuclear cells (MNC) containing at least 70% leukemic blasts were isolated from bone marrow of untreated AML and cultured in the presence of 3000 IU/ml recombinant IL-2 (rIL-2) for 6-8 weeks. Under these conditions, T-cells were selected in the bone marrow cultures and overgrew the leukemic blasts. The resulting T-cell populations were cloned by limiting dilution and the clones obtained were characterized for their phenotypical and functional patterns. Totally, cloning resulted in 68 clones and a few cell lines. The clonality was verified by RT PCR analysis of TCR V beta gene expression. All clones obtained stained positive for CD2, CD3, DR and CD56. The vast majority (68%) of T-cell clones/lines was CD4+, a few clones expressed CD8 (19%) or CD4 and CD8, and four clones were of TCR gamma delta origin. Seven of 15 clones tested, including three CD4+, two CD8+ and two TCR gamma delta(+)-clones were found to be cytotoxic against autologous leukemic blast cells. All except one clone expressed oncolytic activities against allogeneic blasts too. One of the TCR gamma delta(+)-clones demonstrated NK activity by lysis of K562 targets. The majority of the T-cell-clones released IL-2, IL-8, TNF-alpha, GM-CSF but only a few IFN gamma and expressed high levels of mRNA for IL-2, TGF-beta and IL-10. None of the clones was found to produce IL-3, IL-4, IL-7 and TNF-beta. The data provide evidence of the existence of T-cell precursors in untreated AML bone marrow differentiating to cytotoxic cells with activity against autologous and allogeneic AML blast cells.

Bone Marrow Cells↗
PubMed1995

AML blasts variably express interleukin 2 receptor alpha, beta or gamma chains without measurable effects on proliferation, cytokine message expression or surface expression of adhesion molecules upon stimulation with interleukin 2.

Preliminary clinical studies including interleukin 2 (IL-2) in chemotherapy strategies for treatment of acute myeloblastic leukemia (AML) suggest that IL-2 may improve the disease-free survival of the patients. Because of reports showing interleukin 2 receptor expression on AML blasts, it is important to know whether IL-2 may directly influence these leukemic cells. In initial studies using flow cytometry to analyze surface expression of interleukin 2 receptors (IL-2R), we found expression of the IL-2R alpha chain on blast cells in 26% and of the IL-2R beta-chain in 81% of the patients. To confirm these results at the transcriptional level, we studied the expression of RNA of the IL-2R alpha, beta, and gamma chains by RT-PCR in the bone marrow of 38 newly diagnosed patients with AML and in three AML-derived cell lines. RNA of the alpha chain was detectable in 11/38 patients, the beta chain in 10/38 patients and the gamma chain in 30/38 patients with AML. Blast cells obtained from colonies growing in semisolid media expressed mRNA for IL-2R. RNA for all three IL-2R chains was expressed in lines KG1, HEL 92.1.7 and K562. In comparison with unstimulated cell lines, incubation of the three lines with various amounts of IL-2 over 3 and 14 days did not increase their growth or change message expression of IL-2R, IL-10, and TGF-beta and surface expression of the adhesion molecules CD 11, CD 18, CD 29 and CD 54. In conclusion, despite expression of IL-2 receptors, AML blasts do not respond to IL-2 by proliferation, message expression for various cytokine genes and surface expression of cellular adhesion molecules.

Base Sequence↗
PubMed1995

Recombinant human granulocyte-macrophage colony-stimulating factor after combined chemotherapy in high-grade non-Hodgkin's lymphoma--a randomised pilot study.

High-grade non-Hodgkin's lymphomas (NHL) can potentially be cured with combination chemotherapy, although the optimum schedules still have to be defined. Clinical trials with intensive chemotherapy are predominantly limited by myelosuppression. Here, haematopoetic growth factors open up the possibility of reducing chemotherapy-associated toxicities. In this randomised pilot study, we investigated the effects of a recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) following combined chemotherapy with vincristine, doxorubicin, cyclophosphamide, prednisone and etoposide (VACPE). A total of 35 patients with high-grade NHLs were randomised to receive either rhGM-CSF or placebo during the first two chemotherapy cycles and rhGM-CSF for all following cycles. rhGM-CSF was administered at a dosage of 5 micrograms/kg for 10 days or until neutrophils were > 1/nl following chemotherapy. The analyses revealed a significant reduction of neutropenia and duration of neutropenia in the rhGM-CSF group. Adverse events were rare and generally mild apart from one anaphylactoid reaction. No effects of rhGM-CSF were observed concerning the platelet nadir or duration of thrombocytopenia. The benefit of rhGM-CSF for response induction and survival via rhGM-CSF-supported dose intensification remains to be determined.

Adolescent↗
PubMed1995

Vincristine, doxorubicin, cyclophosphamide, prednisone and etoposide (VACPE) in high-grade non-Hodgkin's lymphoma--a multicenter phase II study.

BACKGROUND: Patients with high-grade non-Hodgkin's lymphoma (NHL) can potentially be cured by intensive chemotherapy. However, many patients still die of their disease, which underscores the need to define patient groups with different long-term prognoses and for more effective and possibly risk-adapted treatment approaches. PATIENTS AND METHODS: In this phase II study we investigated the feasibility and efficacy of a polychemotherapy consisting of 2 mg vincristine (V) on day 1, 25 mg/m2 doxorubicin (A) days 1-3, 800 mg cyclophosphamide (C) day 1, 60 mg/m2 prednisone (P) days 1-7 and 120 mg/m2 etoposide (E) days 1-3. This cycle (VACPE) was repeated on day 22 for up to 5 cycles in stages I-III and 6 cycles in stage IV, respectively, followed by consolidating radiotherapy in 38/73 patients. A total of 75 patients with high-grade NHLs according to the Kiel classification were eligible, and 73 patients are evaluable for response. The predominant histological subtypes were centroblastic, pleomorphic T-cell and large-cell anaplastic lymphomas, 60% of the patients presented with stage III/IV, 55% with a poor performance status (ECOG > or = 2), 53% with B symptoms and 60% with a LDH level >200 U/l. RESULTS: 57/73 patients achieved CR (78%), and the overall response rate (CR-PR) was 95%. The median observation time is 40 months (10+-74+). The 1-, 3- and 5-year overall survivals for the entire VACPE group were 79%, 64% and 61%, respectively. Forty-one patients are in ongoing CR with a continuous complete remission rate (CCR) of 67%. Fourteen of the 16 patients who relapsed (88%) did so within the first 24 months. The predicted 1-, 3- and 5-year DFS for those patients who achieved CR is 83%, 67% and 67%, respectively. The early mortality was 3/73 (4.1%). In patients with reduced performance status the overall survival (OS) (ECOG > or = 2) was significantly reduced, with a predicted 1-, 3- and 5-year survival of 62%, 49% and 49% versus 100%, 84% and 77% in patients with favorable performance status, respectively (p = 0.001). The predicted overall survival in stages III/IV is worse than in early stages with a 1-, 3- and 5-year probability of 73%, 52% and 52% versus 90%, 86% and 78%, respectively (p = 0.02). Comparison of patient groups with cumulative risk factors shows a significant decrease in overall survival. Especially in patients with 0-2 risk factors versus those presenting with >2 risk factors, there is a significantly better 3- and 5-year survival (p = 0.002). In contrast to overall survival, there were no differences between the listed risk groups concerning the disease-free survival of complete responders. CONCLUSION: In conclusion, the VACPE regime is feasible and effective in high-grade NHLs and may also be administered on an outpatient basis. Despite encouraging data, however, a prospective randomized trial is warranted to define a possible superiority to standard CHOP. However, this regimen may be the basis for further randomized and risk adapted innovative approaches for high-grade NHLs.

Adolescent↗
PubMed1995

The Wilms' tumor gene is frequently expressed in acute myeloblastic leukemias and may provide a marker for residual blast cells detectable by PCR.

BACKGROUND: The tumor suppressor gene wt-1 was isolated by cytogenetic deletion analysis of patients with Wilms' tumor (wt-1). This gene encodes for a zinc finger DNA-binding protein with transcription-repressing properties. During normal ontogenesis it is expressed in a time- and tissue-dependent manner mainly in the kidneys and gonads. Recently, the expression of wt-1 in acute leukemias (AL) was reported. Here we investigated the prognostic potential of wt-1 mRNA expression during the course of the disease using the PCR technique. PATIENTS AND METHODS: Blast cells from 83 patients with newly diagnosed AML and 20 AML patients during follow-up in complete remission were analyzed for wt-1 mRNA expression. Peripheral blood mononuclear cells (PBMNC) and bone marrow (BM) from healthy persons (n = 13) and sorted CD34-positive cells from normal donors (n = 4) were used as negative controls. RESULTS: Wt-1-specific m-RNA was detectable in 67/83 (81%) patients with AML. Normal donors did not express wt-1 m-RNA but in 1/4 sorted CD34+ cell samples a weak amplified product was observed. After achieving cytological CR 14/20 studied patients lost wt-1 expression. In 7/8 patients in morphological CR the reappearance of wt-1 expression preceded relapse of the disease, in 1/8 patients wt-1 remained positive in CR. Response to therapy, disease-free survival, overall survival and FAB-subtype did not correlate with wt-1 m-RNA expression in newly diagnosed AML before therapy. CONCLUSIONS: In the majority of acute leukemias wt-1 is expressed and probably blast cell-associated, at least in levels detectable by PCR. Wt-1 mRNA was detectable in bone marrow cells of AML patients in clinical CR. The results strongly suggest that the persistence or reappearance of wt-1 predicts relapse of the disease prior to morphological relapse.

Adult↗
PubMed1995

Interleukin-2 bolus infusion as late consolidation therapy in 2nd remission of acute myeloblastic leukemia.

The activation of autologous cytotoxic cells by interleukin-2 (IL-2) may be a promising tool for elimination of minimal residual blast populations in patients with acute myelocytic leukemia (AML) to prolong disease-free survival. Here, we report the results of a phase II study using IL-2 for consolidation therapy in patients with second remission of de novo AML. All patients in 1st relapse of AML received a uniform induction therapy consisting of intermediate high-dose AraC (iHDAraC) 2 x 600 mg/m2 d1-4 and VP-16 100 mg/m2 d1-7. Patients achieving 2nd remission were treated with 4 cycles recombinant IL-2 (rIL-2) 9 x 10(6) IU/m2 administered on d1-5 and 8-12/cycle as 1h infusion every six weeks. In 37/66 (56%) evaluable patients, complete remission (CR) was achieved. So far, 21/37 patients (4 after additional autologous bone marrow transplantation (ABMT) received rIL-2 consolidation. Three patients are too early for evaluation, 4 received allogeneic BMT, 6 relapsed before IL-2 was scheduled and 4 refused treatment with rIL-2. The median disease-free survival (DFS) was 11 (4-49+) months. Up to now, in 5/21 (24%) patients the duration of 2nd remission exceeded that of 1st remission 7/21 (33%) are in ongoing 2nd remission (7+ to 49+ months). The side effects of rIL-2 were generally moderate and manageable. Only in two patients, previously treated with ABMT, severe side effects occurred; septicaemia and pneumonia in one patient and desquamative erythrodermia in the second one. In accordance with other studies rebound lymphocytosis with a marked increase of CD56(+)-cells and release of secondary cytokines such as TNF-alpha, IFN-gamma and IL-6 was observed. The schedule is feasible and the data suggest a possible benefit for DFS, which, however has to be confirmed by randomized trials.

Adult↗
PubMed1995

Clinical experience with fludarabine and its immunosuppressive effects in pretreated chronic lymphocytic leukemias and low-grade lymphomas.

Fludarabine monophosphate (FAMP) is a new adenine nucleoside analogue with a promising efficacy in B-cell chronic lymphocytic leukemia (B-CLL) and low-grade non-Hodgkin lymphomas (NHLs). Here, the clinical experience and side effects with FAMP are reported in 77 patients with pretreated CLL (59 B-CLL, 2 T-CLL) and low-grade NHLs (9 immunocytic lymphomas including 5 Waldenström's macroglobulinaemia, 2 centrocytic (cc) and 5 centroblastic-centrocytic (cb-cc) NHLs). 70/77 patients are evaluable for response. All except 8 patients were pretreated with one to four different regimens and had progressive disease. FAMP was administered at a dosage of 25 mg/m2 daily for 5 days as 30 minute infusion every fifth week. Partial (PR) or complete remission (CR) was achieved in 38/56 (68%) and 3/56 (5%) of evaluable patients with CLL, respectively. In 7/8 (1 x CR, 6 x PR) evaluable patients with immunocytic lymphoma and in 3/6 (3 x PR) patients with cc or cb-cc lymphoma remissions were obtained. The probability of progression-free survival was 66% and the event-free survival was 25% and 22% at 12 and 18 months. The median progression-free survival until relapse or death, however, was only 7 months (2-20+). Major toxic effects included infections in 22 patients (grade 3 and 4 WHO), granulocytopenia (mainly grade 3) and nausea in 8 patients (mainly grade 1). 19/22 patients were in PR at the time of occurrence of infectious complications. Meanwhile, 14 patients died due to septicaemia, pneumonia or other infections. Nine patients developed severe septicaemia, 4 patients had pneumocystis carinii or aspergillus pneumonias. The high infection rate may not only be due to hypogammaglobulinaemia and granulocytopenia induced by FAMP but also to a remarkable decrease of CD4+ cells from a median of 2479 to 241 CD4+ cells/microliters after 6 cycles of FAMP. In one case a tumor lysis syndrome was observed. No CNS toxicity was noted. It is concluded that FAMP is effective even in patients with advanced CLL and low-grade NHLs refractory to multiple chemotherapy regimens. However, FAMP has a marked suppressive effect on granulocytes and T-lymphocytes, predominantly CD4+ lymphocytes.

Adult↗
PubMed1995

Characterization of the mononuclear cell infiltrate in the glomerulus of rats with glomerulonephritis.

Bone marrow-derived inflammatory cells contribute to glomerular damage in experimental glomerulonephritis. The time sequential appearance and the pattern of inflammatory cells in the diseased glomerulus is, however, unclear. We therefore characterized the inflammatory cell infiltrate in a model of unilateral in situ immune complex glomerulonephritis. The cellular infiltrate was specific for the diseased kidney and independent of changes in peripheral blood or spleen. We found an influx of leukocyte common antigen (LCa)-positive and ED1-positive (monocytes/macrophages) cells in isolated glomeruli as early as 24 h after induction of the disease. Lymphocytes of the CD4-, CD8- and CD20-positive phenotypes were present in diseased glomeruli at Day 10. Complement depletion prevented the influx of monocytes/macrophages at 24 h in the glomerulus, which indicates that complement activation is important for the glomerular cell infiltrate at this early time point. The results demonstrate that the inflammatory cell infiltrate is regulated in situ at the glomerular level and not accompanied by similar changes in peripheral blood and spleen cells.

Animals↗
PubMed1995

The inhibition of lymphokine-activated killer cells in acute myeloblastic leukemia is mediated by transforming growth factor-beta 1.

In acute myeloblastic leukemia (AML), the T cell response and cytotoxic activity are impaired at time of diagnosis due to not-yet-identified soluble immunosuppressing factors. The inhibition of autologous antileukemic immune response by these factors may support immunosurveillance of AML. A well-known inhibitor of lymphokine-activated killer (LAK) cell activity is transforming growth factor-beta 1 (TGF-beta 1). To evaluate the possible significance of TGF-beta 1 for the impaired cytotoxic activity in AML at time of diagnosis, we looked for the TGF-beta 1-specific mRNA, for the production and release of TGF-beta 1, and for its relevance for immunosuppressing activities in AML. In the culture supernatants of 18 investigated AMLs, we detected various amounts of TGF-beta protein. The TGF-beta 1 and TGF-beta 2 protein concentrations were 105 pg/mL (< 50-240 pg/mL) and 32 pg/mL (< 2-91 pg/mL), respectively. In 13 of 15 patients, the leukemic blasts expressed TGF-beta 1 mRNA. To exclude possible interferences with contaminating mononuclear cells (MNC), the data were confirmed by analysis of sorted blast cells and leukemic cell lines. All investigated leukemic cell lines expressed TGF-beta 1 protein and mRNA. The culture supernatants of AMLs inhibited LAK activity strongly in a dose-dependent manner. The inhibition of cytotoxicity could be restored by the addition of neutralizing TGF-beta 1 antibodies. The data suggest TGF-beta 1 to be a relevant factor for the inhibition of cytotoxic activities in AMLs.

Adult↗
PubMed1994

AIDS-free survival and overall survival in HIV infection: the new CDC classification system (1993) for HIV disease and AIDS.

The clinical history of 1538 HIV positive patients was analyzed on the basis of the new CDC classification system of HIV disease and AIDS. This classification system combines three CD4 cell categories (1, 2, and 3) with three clinical categories (A, B, and C) into nine subgroups A1-C3. We examined the overall survival for all subgroups and the AIDS-free survival for subgroups A1-B3. AIDS-free survival for patients in subgroups A1, A2, and B1 was considerably longer than survival in patients from subgroups A3, B2, and B3 (P < 0.0001). According to these findings, the new CDC classification system could be simplified into three stages, stage I and II comprising the above mentioned six subgroups, and stage III comprising clinical AIDS defining categories C1, C2, and C3. These three stages correspond to different periods in the management of HIV positive patients, i.e., period of observation, period of prophylaxis, and period of treatment.

Acquired Immunodeficiency Syndrome↗
PubMed1994

In vivo regulation of transforming growth factor beta 1 transcription by immunotherapy: interleukin-2 impairs interferon-alpha-stimulated increase in steady-state mRNA levels of transforming growth factor beta 1.

Recombinant interleukin-2 (rIL-2) in combination with recombinant interferon alpha (rIFN alpha) has been shown to mediate significant antitumoral effects in some patients with advanced renal cell cancer or malignant melanoma. The therapeutic effects may be partially modulated by secondarily induced cytokines, especially with regard to in vivo lymphocyte activation. To investigate possible negative effects on lymphocyte activation during immunotherapy, we designed a study on transcription of transforming growth factor beta 1 (TGF beta 1), a known inhibitor of lymphocyte function, in patients undergoing treatment with daily alternating administration of rIFN alpha and rIL-2. Here we present data on gene expression of TGF beta 1. Kinetic mRNA studies revealed an increase of TGF beta 1 mRNA in peripheral mononuclear cells 12 h after subcutaneous injection of rIFN alpha. The following intravenous rIL-2 administration significantly decreased the amounts of TGF beta 1-specific mRNA. In contrast to the effect of the first dose, subsequent application of rIFN alpha did not enhance TGF beta gene expression during rIFN alpha/IL-2 therapy. The diminished TGF beta 1 gene expression returned to pretreatment levels 1-7 days after the last rIL-2 administration. When concomitant with a decrease in TGF beta 1 transcripts. Our results indicate a complex regulatory effect on secondarily induced cytokines such as TGF beta 1 by immunotherapeutic approaches. The rIL-2-mediated down-regulation of increased TGF beta 1 steady-state mRNA levels following rIFN alpha may represent a positive immune regulatory effect on cytotoxic cells. Furthermore this effect may modulate proliferation of neoplastic tissues.

Autoradiography↗