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T Sauerbruch

Publications and source records attributed to T Sauerbruch.

At least 91 records · Page 5Linked to original sources
PubMed2002

Acute transient encephalopathy after paclitaxel infusion: report of three cases.

Paclitaxel (Taxol) is a diterpene plant product and antineoplastic agent that promotes the assembly of microtubules as well as stabilizing their formation by preventing depolymerization. Myelosuppression was found to be dose-limiting, but peripheral neurotoxicity is also a well known side-effect. Central nervous system toxicity is rare, probably because paclitaxel does not cross the blood-brain barrier. We observed three patients who presented with acute encephalopathy within 6 h after infusion of paclitaxel at normal doses. All patients had received prior whole brain irradiation (WBI) and one patient had prior brain metastasectomy. Computer tomography and magnetic resonance imaging showed no evidence of cerebral metastases. An effect from other organ toxicities was excluded in all patients. All recovered spontaneously within 4-6 h. From this we can conclude that paclitaxel can cause severe acute transient encephalopathy, which may occur more frequently after prior WBI and/or surgery due to alteration of small vessel function.

Aged↗
PubMed2001

Clostridium difficile infection in patients with neutropenia.

Clostridium difficile is the most important cause of nosocomial infectious diarrhea. The importance of C. difficile-associated diarrhea (CDAD) has been poorly investigated in patients with neutropenia who have hematologic malignancies. A retrospective chart review of all patients treated in the leukemia ward of a university medical center during 1991-2000 determined that 875 courses of myelosuppressive chemotherapy were administered. CDAD occurred in 7.0% of all cycles. In 8.2% of the patients, severe enterocolitis developed. Two patients died while they had diarrhea. However, in no patient was C. difficile infection clinically considered to be the primary cause of death. The response rate to oral metronidazole was 90.9%. These data indicate that C. difficile infection is not rare and should be suspected whenever a hospitalized patient with neutropenia develops diarrhea. Oral metronidazole can be recommended as initial drug of choice for treatment of patients with neutropenia who have hematologic malignancies and CDAD.

Adolescent↗
PubMed2001

Therapeutic vaccination against metastatic carcinoma by expression-modulated and immunomodified autologous tumor cells: a first clinical phase I/II trial.

Therapeutic vaccination of tumor patients with cytokine gene-transfected tumor cells leads to tumor regression in animal models but has so far not resulted in significant clinical benefit. We and others demonstrated that tumor cells transfected to mediate overexpression of a cytokine gene activate immunologic effector cells for an improved proliferation rate and significantly higher antitumoral cytotoxic activity. Here, we performed a pilot study of therapeutic vaccination in patients with metastatic disease. Autologous tumor cells were simultaneously transfected with novel minimalistic, immunogenically defined, gene expression constructs (MIDGE) for overexpression of the two cytokines interleukin 7 (IL-7) and GM-CSF and newly designed double stem-loop immunomodulating oligodeoxyribonucleotides (d-SLIM) as a Th1-promoting and NK cell-stimulating adjuvant. Transfection was performed ex vivo by ballistomagnetic gene transfer. Patients received four subcutaneous injections of at least 1 x 10(6) of their expression-modulated and immunomodified autologous tumor cells. Ten patients have been enrolled in the study protocol. In all patients no adverse effects could be detected. IL-7 and interferon gamma levels were elevated in the serum of the patients after treatment. Interestingly, cytotoxicity of patient-derived PBLs increased significantly during treatment. All 10 patients had progressive disease when entering our protocol. One complete, one partial, and one mixed response with progression of abdominal metastases and regression of lung metastases were observed. Two patients showed a stable disease after treatment and five patients remained in progressive disease. Our observations confirm the capability of autologous expression-modified and immunomodulated tumor cell vaccines to stimulate a strong immune response in patients with metastatic cancer even in the presence of a large tumor burden.

Aged↗
PubMed2001

Intrahepatic MxA expression is correlated with interferon-alpha expression in chronic and fulminant hepatitis.

Interferon-alpha (IFN-alpha) has potent pro-inflammatory and anti-viral functions. It exerts its effects by inducing intracellular proteins such as MxA. To analyse the role of intrahepatic interferon activation, IFN-alpha and MxA expression was studied by immunohistochemistry in explant livers of 20 patients with fulminant hepatic failure (FHF), 41 patients with chronic liver disease (CLD), and ten normal controls (NCs). In NCs only small numbers of Kupffer cells, but no hepatocytes, showed IFN-alpha and MxA expression. In contrast, significantly enhanced numbers of IFN-alpha- and MxA-positive Kupffer cells, along with small numbers of MxA-positive and larger numbers of IFN-alpha-positive lymphocytes, were found in CLD and in FHF. MxA protein was also expressed on hepatocytes and bile ducts in the vicinity of IFN-alpha-positive inflammatory infiltrates (hepatocytes: NCs: 0%, CLD: 8%, FHF: 68%; bile ducts: NCs: 19%, CLD: 46%, FHF: 83%). A significant correlation was found between the numbers of IFN-alpha- and MxA-positive cells (r=0.67, p<0.001). Thus, large amounts of IFN-alpha are released in the livers of patients with FHF, which is likely to contribute to immune-mediated liver cell damage. Intrahepatic MxA expression corresponds to IFN-alpha produced particularly by infiltrating inflammatory cells, rather than by hepatocytes themselves.

Antiviral Agents↗
PubMed2001

Resistance of pancreatic carcinoma cells is reversed by coculturing NK-like T cells with dendritic cells pulsed with tumor-derived RNA and CA 19-9.

Immunization with defined tumor antigens is limited to the small number of cancers in which specific tumor antigens have been defined but insufficient tumor material is available to produce an antitumor vaccine. In this study, we investigated whether pulsing dendritic cells (DC) using a liposomal transfer technique with a pancreatic tumor cell line-derived RNA can effectively activate NK-like T cells and tumor immunity. Pulsed DC were cocultured with NK-like T cells, i.e., CD3+CD56+ cells, as immunologic effector cells. Target cells resistant to NK-like T-cell-mediated lysis were used. Total tumor-derived RNA transfected into DC was found to completely reverse tumor cell resistance. Total tumor RNA transfection (30 microg) was found to be superior to poly(A)(+) RNA transfection (5 microg) in inducing NK-like T lymphocytes. Interestingly, additional pulsing of DC with the CA 19-9 peptide in a CA 19-9-positive cell line further increased the sensitivity of pancreas carcinoma cells to NK-like T cells. Treatment of tumor RNA with RNase completely blocked the effect of RNA-transfected DC on NK-like T cells, suggesting that intact tumor-derived RNA is needed for reversal of tumor cell resistance. In conclusion, coculture of NK-like T cells with DC transfected with pancreatic tumor cell line-derived RNA reverses pancreatic tumor cell resistance by directly triggering NK-like T lymphocytes.

CA-19-9 Antigen↗
PubMed2001

A novel minimal-size vector (MIDGE) improves transgene expression in colon carcinoma cells and avoids transfection of undesired DNA.

Viral and plasmid vectors may cause unwanted immunological side effects resulting from the expression of nontherapeutic genes contained in their sequence. Furthermore, replication-defective viral vectors carry the potential risk of recombination with wild-type viruses or activation of oncogenes. A new vector type for minimalistic, immunologically defined gene expression (MIDGE) may overcome these problems. MIDGE is a minimal-size gene transfer unit containing the expression cassette, including promoter, gene, and RNA-stabilizing sequence, flanked by two short hairpin oligonucleotide sequences. The resulting vector is a small, linear, covalently closed, dumbbell-shaped molecule. DNA not encoding the desired gene is reduced to a minimum. Here, we transfected colon carcinoma cell lines using cationic lipid, cationic polymer, and electroporation with several MIDGE vectors and corresponding plasmids containing transgenes encoding enhanced green fluorescent protein (eGFP) and human interleukin-2 (hIL-2). Transfection efficiency as measured qualitatively and quantitatively with eGFP was found to be comparable for both vector types. However, hIL-2 secretion and eGFP expression were approximately two- to fourfold higher in most cells transfected with these transgenes using MIDGE vectors compared to the plasmid control. This report demonstrates the advantages of this new vector type and its prospects for ex vivo gene therapy studies.

Cations↗
PubMed2001

Littoral cell angioma as a rare cause of splenomegaly.

A 58-year-old, otherwise healthy man presented with a sudden onset of watery diarrhea. A pseudomembranous colitis due to antibiotics was identified as the cause of the diarrhea. Enlargement of the spleen was detected during the evaluation. The enlarged, plump spleen (20 cm long, 7.1 cm wide) had multiple nodules that differed in size from 1 to 8 cm. Neither clinical nor other symptoms of an underlying malignant disease could be detected. Because the signs were of little diagnostic value we arranged a splenectomy, which showed a littoral cell angioma (LCA) to be the cause of splenomegaly. In addition to the case report, we have reviewed the literature, clinical manifestations, differential diagnosis, special gross and microscopic pathological findings, and the location of this benign vessel tumor in the pathology of the spleen.

Hemangioma↗
PubMed2001

Natural cytotoxicity and antibody-dependent cellular cytotoxicity (ADCC) is not impaired in patients suffering from chronic hepatitis C.

BACKGROUND/AIMS: Recent observations suggest that natural killer (NK) cell activity might be impaired in chronic hepatitis C. However, to date antibody-dependent cellular cytotoxicity (ADCC) has not been studied in chronic hepatitis C in detail. METHODS: Therefore, we investigated spontaneous and cytokine-induced (interleukin-2 and interferon-gamma) natural cytotoxicity and ADCC in 29 patients suffering from chronic hepatitis C and 19 healthy controls. Cytotoxicity was determined with a flow-cytometric assay, which can also assess monocyte cytotoxicity. As target cells we used the colorectal tumor cell line HT29 and the lymphoma cell line Raji. RESULTS: We found no significant differences with respect to spontaneous cytotoxicity (HCV versus healthy controls (32 vs. 46%) and 17-1A specific ADCC (59 vs. 48%), even if isolated monocytes or NK cells were studied. Preincubation and stimulation of effector cells with cytokines increased both natural cytotoxicity and ADCC by 20-30%. However, natural cytotoxicity and ADCC after stimulation did not differ between the two groups. CONCLUSIONS: Our data obtained with a long-term cytotoxicity assay do not reveal impaired cytolytic capacity of the innate immune system in chronic hepatitis C, even when isolated monocytes and NK cells were studied as effector cells.

Adult↗
PubMed2001

Transfection of dendritic cells (DCs) with the CIITA gene: increase in immunostimulatory activity of DCs.

Dendritic cells (DCs) are the major antigen-presenting cells. They are able to present tumor antigens to immunologic effector cells. MHC class II molecules on DC surfaces play an important role in priming effector cells against tumor cells and their antigens. The transactivator CIITA (MHC class II transactivator) is a non-DNA-binding transactivator, which regulates the expression of MHC class II, HLA-DM, and invariant chain and behaves as a master controller of constitutive and inducible MHC class II gene activation. Here, we transfected DCs with the CIITA gene using a novel transfection technique. The vector system consisted of a plasmid bound to an adenovirus via poly-L-lysine, which is covalently bound to a UV-irradiated adenovirus. After transfection, expression of MHC class II on DCs increased from 27% to 75% on day 2 after transfection. Transfected DCs were co-cultured with immunologic effector cells. Cytotoxicity of effector cells against tumor cells increased after co-culture with transfected DCs to 63% compared to 15% with effector cells co-cultured with irrelevantly transfected DCs (P=.037). This effect was dependent on the timing and period of co-culture. In conclusion, transfection of DCs led to an increase in antitumoral immunostimulatory capacity of DCs. We can further conclude that DCs could be efficiently transfected with the CIITA gene. Transfection of DCs led to an increase in antitumoral immunostimulatory capacity of DCs and may have a major impact on immunotherapeutic protocols for patients with cancer.

Adenoviridae↗
PubMed2001

Influence of cytokines, monoclonal antibodies and chemotherapeutic drugs on epithelial cell adhesion molecule (EpCAM) and LewisY antigen expression.

MoAbs against tumour-associated antigens (TAA) may be useful for the treatment of colorectal cancer. Since an increased expression of TAA may lead to enhanced antibody-dependent cellular cytotoxicity we examined whether the cytokines IL-2, IL-4, IL-6, IL-10, IL-12, interferon-alpha (IFN-alpha), IFN-gamma, granulocyte-macrophage colony-stimulating factor, macrophage colony-stimulating factor and tumour necrosis factor-alpha can influence EpCAM and LewisY expression on the surface of the colorectal carcinoma cell lines HT29, LoVo and SW480. We found that only IFN-alpha increased significantly whereas IL-4 decreased both EpCAM and LewisY expression. IFN-gamma significantly increased LewisY expression only. When tumour cells were treated with MoAb, the LewisY-specific MoAb BR55-2 down-regulated LewisY antigen expression, whereas MoAb 17-1A, which binds to EpCAM, up-regulated this TAA after 3 days of culture. The cytokines IFN-alpha or IFN-gamma combined with MoAb 17-1A enhanced further slightly the expression of EpCAM. In additional experiments with chemotherapeutic drugs commonly used for the treatment of colorectal cancer, we found that 5-fluorouracil, mitomycin-C and oxaliplatin up-regulated EpCAM and LewisY antigen expression. Raltitrexed enhanced LewisY and down-regulated EpCAM expression, whereas CPT-11 had no influence at all. The highest expression for EpCAM on HT29 cells was achieved by the combination of IFN-alpha, 5-fluorouracil and MoAb 17-1A. Our results may be useful for defining combinations of biological and chemotherapeutic drugs for the treatment of colorectal cancer. Further trials should evaluate to what extent these combinations enhance antibody-dependent cellular cytotoxicity.

Adjuvants, Immunologic↗
PubMed2001

Differentiation of antineutrophil nuclear antibodies in inflammatory bowel and autoimmune liver diseases from antineutrophil cytoplasmic antibodies (p-ANCA) using immunofluorescence microscopy.

Perinuclear antineutrophil cytoplasmic antibodies (p-ANCA) directed against cytoplasmic proteins of neutrophils have been studied extensively in patients with systemic vasculitides. Recent data indicate that antineutrophil antibodies in sera from patients with chronic inflammatory bowel diseases (IBD) or autoimmune liver disorders, currently called 'atypical p-ANCA', recognize a nuclear target antigen, rendering the term 'ANCA' inaccurate. Specific microscopic criteria to distinguish atypical p-ANCA from p-ANCA are lacking. We used planar and confocal laser scanning indirect immunofluorescence microscopy to examine the labelling characteristics of ethanol-, methanol- and formaldehyde-fixed neutrophils by antineutrophil antibodies in 153 serum samples from patients with IBD, autoimmune liver disorders, systemic vasculitides or healthy blood donors. On ethanol- or methanol-fixed neutrophils, multiple intranuclear fluorescent foci together with either a rim-like peripheral nuclear staining ('type A') or a combined cytoplasmic and peripheral nuclear staining ('type B') was noted exclusively with atypical p-ANCA in sera from patients with IBD or autoimmune liver disorders. Intranuclear foci, which probably corresponded to invaginations of the nuclear envelope, were not labelled by p-ANCA from patients with microscopic polyangiitis or cytoplasmic ANCA (c-ANCA) from patients with Wegener's granulomatosis. On formaldehyde-fixed neutrophils, atypical p-ANCA gave a fine rim-like staining of the nuclear periphery, whereas ANCA diffusely labelled the cytoplasm. To distinguish reliably between the patterns produced by atypical p-ANCA or p-ANCA, particularly p-ANCA, careful indirect immunofluorescence microscopy on ethanol- as well as on formaldehyde-fixed neutrophils is necessary, with particular emphasis on the presence of multiple intranuclear fluorescent foci.

Adolescent↗
PubMed2001

Lipidation of T helper sequences from hepatitis C virus core significantly enhances T-cell activity in vitro.

Successful elimination of the hepatitis C virus (HCV) during acute infection has been linked to strong HCV-specific in vitro T-cell proliferation, whereas T cells from patients with chronic hepatitis C respond only weakly to HCV antigens. Lipid-coupled peptides are immunostimulants, which might provide a basis for novel therapeutic strategies against HCV. Therefore, in 20 patients with chronic hepatitis C, we studied whether tri-palmitoyl-S-cysteine-coupled peptides could modify in vitro T-cell proliferation (by [3H]thymidine uptake) in response to virus core and NS4. The lipopeptides corresponded to five immunodominant T helper epitopes of HCV core. Contrary to unmodified peptides, the lipopeptides specifically enhanced [3H]thymidine uptake in response to HCV antigens but not to a non-HCV related control antigen. They increased the frequency of responders (stimulation index, SI > or = 4) to core (13/20 versus 2/20; p = 0.0008) and NS4 (20/20 versus 7/20; p < 0.0001) among our patients with chronic hepatitis C. This immunostimulatory effect was dose-dependent, and was observed specifically with lipopeptides corresponding to the HCV epitopes. Our data demonstrate that the poor in vitro T-cell proliferation of patients with chronic hepatitis C can be improved when T cells are co-stimulated with HCV core-derived T helper lipopeptides, while the same peptides in unlipidated form had no effects. Thus, lipopeptides corresponding to HCV T-cell epitopes may offer novel immunomodulatory strategies against HCV.

Adult↗