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V Diehl

Publications and source records attributed to V Diehl.

At least 127 records · Page 7Linked to original sources
PubMed2000

Ki-4(scFv)-ETA', a new recombinant anti-CD30 immunotoxin with highly specific cytotoxic activity against disseminated Hodgkin tumors in SCID mice.

The human lymphocyte activation marker CD30 is highly overexpressed on Hodgkin/Reed-Sternberg cells and represents an ideal target for selective immunotherapy. We used the murine anti-CD30 hybridoma Ki-4 to construct a new recombinant immunotoxin (rIT) for possible clinical use in patients with CD30(+) lymphoma. Hybridoma V genes were polymerase chain reaction-amplified, assembled, cloned, and expressed as a mini-library for display on filamentous phage. Functional Ki-4 scFv obtained by selection of binding phage on the CD30-expressing Hodgkin lymphoma cell line L540cy was inserted into the bacterial expression vector pBM1.1 and fused to a deletion mutant of Pseudomonas exotoxin A (ETA'). Periplasmically expressed Ki-4(scFv)-ETA' demonstrated specific activity against a variety of CD30(+) lymphoma cells as assessed by different in vitro assays. To evaluate in vivo antitumor activity, severe combined immunodeficient mice challenged with human lymphoma cell lines were treated with the immunotoxin. The blood distribution time t(1/2)alpha of Ki-4(scFv)-ETA' was 19 minutes, and its serum elimination time t(1/2)alpha was 193 minutes. A single intravenous injection of 40 microg rIT 1 day after tumor inoculation rendered 90% of the mice tumor free, extending the mean survival time to more than 200 days compared with 38.1 days in the phosphate-buffered saline control group (P <.001). This new rIT is a promising candidate for further clinical evaluation in patients with Hodgkin lymphoma or other CD30(+) malignancies. (Blood. 2000;95:3909-3914)

Animals↗
PubMed2000

[Dangerous tropics].

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Disease Transmission, Infectious↗
PubMed2000

Recombinant anti-CD25 immunotoxin RFT5(SCFV)-ETA' demonstrates successful elimination of disseminated human Hodgkin lymphoma in SCID mice.

Since clinical phase-I/II trials in patients with resistant Hodgkin's lymphoma treated with the chemically linked anti-CD25 ricin-A-chain immunotoxin RFT5-SMPT-dgA indicate promising results for patients with minimal residual disease, we constructed a new immunotoxin by fusing the RFT5 single-chain variable fragment to a deletion mutant of Pseudomonas exotoxin A (ETA'). The recombinant protein was directed into the periplasmic space of E. coli by means of the pET-derived expression vector pBM1.1 and our newly developed expression/purification method. Biologically active RFT5(scFv)-ETA' was isolated by freezing/thawing and purified by immobilized metal-ion affinity and molecular-size-chromatography. RFT5(scFv)-ETA' was subsequently used for the treatment of disseminated human Hodgkin's lymphoma in a SCID-mouse model. The mean survival time (MST) of L540rec-challenged SCID mice was 38.1 days. A single i.v. injection of 40 microg recombinant immunotoxin (rIT) 1 day after tumor inoculation resulted in 100% tumor-free mice, extending the MST to more than 220 days (p < 0.0001). The blood-distribution time T(1/2)alpha was 39.65 min, the serum elimination time T(1/2)alpha, 756.6 min. All animals were assessed for soluble interleukin-2 receptor alpha, which is directly correlated to tumor burden. Soluble CD25 was not detectable in mice treated with the rIT. Our findings, concerning potent anti-tumor effects of a recombinant anti-CD25 immunotoxin against disseminated Hodgkin's lymphoma in SCID mice reported here demonstrate that RFT5(scFv)-ETA' might be suitable for further evaluation against Hodgkin's lymphoma in humans.

Animals↗
PubMed2000

Suppression of the tumorigenic growth of Burkitt's lymphoma cells in immunodeficient mice by cytokine gene transfer using EBV-derived episomal expression vectors.

Epstein-Barr virus (EBV)-based expression vectors were tested for cytokine gene transfer-mediated induction of an immune response against human lymphoma cells. These vectors express the EBV latent gene EBNA 1 and carry the EBV latent origin of replication (ori P) for episomal replication in transfected cells. In addition, 3 human immunoglobulin light chain enhancer elements augment expression in B-cells. The suitability of these vectors for expression of cytokine genes in human lymphoma cells in vitro has been demonstrated. In order to extend these experiments in vivo, highly tumorigenic Burkitt's lymphoma (BL) cells were transfected with different cytokine genes of human and murine origin cloned into the EBNA 1/ori P vectors. Tumorigenicity of the transfectants was measured after inoculation into nude mice. No effect on tumorigenicity was observed after hIL 6 transfection and an inconsistent effect after hTNFalpha transfection. In contrast, complete suppression of tumor outgrowth occurred in hIL 10 transfectants. This tumor suppressive effect, however, was restricted to the IL 10 transfectants themselves and not directed against non-transfected cells. By comparison, mIL 4 transfected BL cells also were non-tumorigenic. However, co-inoculation of mIL 4 transfected and non transfected cells resulted in suppression of the tumorigenicity of the non-transfected cells. Thus, highly tumorigenic BL cells in nude mice are sensitive to immune effector mechanisms triggered by cytokine expression. In this experimental model, EBNA 1/ori P expression vectors are a suitable tool for cytokine gene transfer mediated induction of an anti-lymphoma immune response of the host.

Animals↗
PubMed2000

[Thrombotic thrombocytopenic purpura (Moschkowitz-syndrome) caused by ticlopidine].

BACKGROUND: Only in a few case reports the thrombotic thrombocytopenic purpura was related to ticlopidine with a controversial discussion about this association. CASE REPORT: In a 57-year-old female patient, who was admitted with fluctuating central neurological abnormalities and generalized purpura, was made the diagnosis of a thrombotic thrombocytopenic purpura (TTP, Moschcowitz' syndrome). On admission there were a distinct anemia and thrombocytopenia. Corresponding to the hemolysis the laboratory findings showed raised reticulocytes and elevated LDH with > 900 U/l. The peripheral blood smear showed an enrichment of fragmented red cells (15%) and the bone marrow indicated a hyperplastic erythrocytopoesis and a left shift in megakaryocytopoesis. An increase of eosinophilic granulocytes and the tissue basophilic cells directed to a possible allergic phenomenon of the underlying disease. Until 3 weeks before admission she had been on ticlopidine after a left heart catheter with stenting the left coronary artery 6 weeks earlier. Beside taking of acetylsalicylacid and thyroid hormone there was no other regular medication. An early treatment with fresh frozen plasma and plasmapheresis with plasma exchange with fresh frozen plasma led directly to an elevation of thrombocytes and a normalization of hemolytic parameters. CONCLUSION: This case demonstrates the possible relationship between thrombotic thrombocytopenic purpura and the administration of ticlopidine.

Female↗
PubMed2000

Tissue eosinophilia correlates strongly with poor prognosis in nodular sclerosing Hodgkin's disease, allowing for known prognostic factors.

Although eosinophilic granulocytes are frequently observed in lymphatic tissue of Hodgkin's patients, no substantial data reveal the prognostic role, if any, of tissue eosinophilia. Thus, eosinophilia was analyzed histologically in 1511 diagnostic biopsy specimens of patients treated under protocol therapy of the German Hodgkin's Lymphoma Study Group between 1988 and 1994. Prominent eosinophilia was seen in 38% of cases, which differed among the histologic types of Hodgkin's disease (HD): none in lymphocyte predominant, 14% in lymphocyte rich classical, 40% in nodular sclerosis grade 1 (NS-1), 55% in nodular sclerosis grade 2, 43% in mixed cellularity (MC), and 54% in lymphocyte depleted. In a multivariate analysis, tissue eosinophilia proved to be the strongest prognostic factor for freedom from treatment failure (P <. 001) and overall survival (P <.001) in a stage-stratified model. Among NS-1 patients, the effect was highly significant. In MC, no significant effect of eosinophilia on survival could be demonstrated. Eosinophils secrete CD30 ligand that is capable of binding to CD30 positive HD cells. The activation of TRAF2, followed by NF-kappaB, which occurs on CD30L/CD30 binding, may explain the neoplastic proliferation and apoptosis protection of HD cells. TRAF2 is also activated by EBV-LMP expression, which is detectable in the majority of MC but not NS cases. In addition to the possibility that eosinophils are only passive indicators for other unknown prognostic determinants, it may be concluded that the positive clinical outcome of eosinophilia-negative NS cases could be due to lower NF-kappaB activity. (Blood. 2000;95:1207-1213)

Adolescent↗
PubMed2000

Clonal deleterious mutations in the IkappaBalpha gene in the malignant cells in Hodgkin's lymphoma.

Members of the nuclear factor (NF)-kappaB family of transcription factors play a crucial role in cellular activation, immune responses, and oncogenesis. In most cells, they are kept inactive in the cytosol by complex formation with members of the inhibitor of NF-kappaB (IkappaB) family, whose degradation activates NF-kappaB in response to diverse stimuli. In Hodgkin's lymphoma (HL), high constitutive nuclear activity of NF-kappaB is characteristic of the malignant Hodgkin and Reed-Sternberg (H/RS) cells, which occur at low number in a background of nonneoplastic inflammatory cells. In single H/RS cells micromanipulated from histological sections of HL, we detect clonal deleterious somatic mutations in the IkappaBalpha gene in two of three Epstein-Barr virus (EBV)-negative cases but not in two EBV-positive cases (in which a viral oncogene may account for NF-kappaB activation). There was no evidence for IkappaBalpha mutations in two non-HL entities or in normal germinal center B cells. This study establishes deleterious IkappaBalpha mutations as the first recurrent genetic defect found in H/RS cells, indicating a role of IkappaBalpha defects in the pathogenesis of HL and implying that IkappaBalpha is a tumor suppressor gene.

Adult↗
PubMed2000

Congenital dyserythropoietic anemia type III associated with congenital atrioseptal defect has led to severe cardiac problems in a 32-year-old patient.

We report the case of a 32-year-old woman who was admitted at hospital because of ortho-dyspnea, arrhythmia, and paleness. Clinical examination showed continuous arrhythmia, systolic heart murmur, enlargement of spleen and liver, and pathologic hematological parameters, thus indicating an intravasal hemolysis (elevated HBDH, bilirubin, and reticulocytes; reduced hemoglobin and haptoglobin levels), and bone-marrow-smears showed a typical cytomorphology of CDA III. The patient's diagnosis was heart failure caused by mitral valve insufficiency due to congenital atrioseptal defect associated with congenital dyserythropoietic anemia type III (CDA III).

Adult↗
PubMed2000

Increase of anti-inflammatory cytokines in patients with esophageal cancer after perioperative treatment with G-CSF.

Granulocyte colony-stimulating factor (G-CSF) has been shown to effectively stimulate granulopoiesis, in both neutropenic and in non-neutropenic patients. Recently, other effects of G-CSF on the immune system have attracted interest in treating non-neutropenic patients with a high risk of severe infection. In this phase II trial, we measured the effects of G-CSF on the serum cytokine levels in patients with esophageal cancer undergoing esophagectomy. Twenty subsequent patients (study group, 19 evaluable) received G-CSF (rhG-CSF, Filgrastim) at standard doses (300 microg or 480 microg) subcutaneously 2 days before and up to 7 days after surgery. G-CSF was well tolerated. Leukocytes increased from 7600/microl at study entry (day -2) to a maximum of 45 100/microl (day 6). In the study patients, we found a highly significant (P<0.001) postoperative increase of G-CSF, IL-1ra, sTNFRp55 and sTNFRp75 as compared with the baseline level. In contrast, IL-8 levels were decreased by a factor of 6.8; there were no changes in the very low TNF-alpha levels. The comparison of the study group with a control group of 21 cancer patients undergoing major surgery who were not treated with G-CSF showed significant differences in the serum levels of G-CSF, sTNFRp55, sTNFRp75, and IL-1ra, respectively. There was no infection in the study group up to 10 days after surgery as compared with 29.9% in a historical control group (P=0.008). Thus, the induction of anti-inflammatory cytokines and the downregulation of pro-inflammatory cytokines by G-CSF might be a promising adjuvant treatment of infectious complications in patients undergoing esophagectomy.

Adenocarcinoma↗
PubMed2000

Ribosomal RNA of Nosema algerae and phylogenetic relationship to other microsporidia.

Microsporidia are intracellular parasites that are common in invertebrates. Taxonomic classification is mostly restricted to morphologic and physiologic data. Limited data are available about taxonomic classification using DNA-sequence data for analysis. We examined the small-subunit (SSU) rDNA, the intergenic spacer (ITS) region, and a part of the large-subunit (LSU) rDNA of Nosema algerae, a parasite of mosquitoes, taken from a laboratory colony of Anopheles stephensi. Target gene amplifications were done by polymerase chain reaction (PCR) and, after cloning, DNA fragments were sequenced. The SSU-rDNA sequence obtained was aligned with several other microsporidian SSU-rDNA sequences available from the GenBank or EMBL data bases and was analyzed by different methods. On the basis of the results of our phylogenetic analysis, we suggest that our N. algerae isolate is not closely related to other microsporidia belonging to the genus Nosema.

Animals↗
PubMed2000

Taxonomic position of the human intestinal protozoan parasite Isospora belli as based on ribosomal RNA sequences.

The taxonomic positions of Isospora belli and other members of the genus Isospora are controversial. We determined the small-subunit ribosomal RNA of I. belli and used this sequence in combination with other coccidian RNA sequences for analysis of the taxonomic position of I. belli. The phylogenetic trees we obtained provide molecular evidence for three clades within a monophyletic group that represents the suborder Eimeriina. The clade containing I. belli consists of tissue-cyst-forming coccidia (Toxoplasma and Neospora) and members of the genus Isospora (I. ohioensis, I. suis, I. belli). The second clade, representing a sister clade of that containing the Isospora species, contains members of the genus Sarcocystis. The third one consists of members of the family Eimeriidae, including Eimeria and Cyclospora species. This shows that although I. belli as well as other members of the genus Isospora belong to the suborder Eimeriina, the family to which they belong is not Eimeriidae but rather Sarcocystidae. We suggest that the genus Isospora should be removed from the family Eimeriidae and placed into the family Sarcocystidae within the suborder Eimeriina.

Animals↗
PubMed2000

Fatal thrombotic thrombocytopenic purpura as a rare complication following allogeneic stem cell transplantation.

Thrombotic thrombocytopenic purpura (TTP) is a rare disease which, together with hemolytic uremic syndrome, is subsumed under thrombotic microangiopathy. After stem cell transplantation (SCT), this syndrome represents a possibly fatal complication with a higher incidence in allogeneic SCT than in autologous SCT. Although plasmapheresis offers an encouraging treatment modality in classic TTP, this seems less effective in bone marrow transplant-associated microangiopathy. This is probably due to a different etiology. We present a case of transplant-associated TTP with a fatal outcome despite multiple courses of plasmapheresis.

Fatal Outcome↗
PubMed2000

How to restrict liver biopsy to high-risk patients in early-stage Hodgkin's disease. German Hodgkin's Lymphoma Study Group.

Liver biopsy is an invasive diagnostic method for detecting liver involvement (LI) in Hodgkin's disease (HD). The aim of this retrospective study was to determine and evaluate a method for restricting liver biopsy to a subset of patients. Between 1988 and 1994, a total of 2,016 patients with HD were treated within the HD4-6 study protocol of the German Hodgkin's Lymphoma Study Group (GHSG). We investigated the predictive power of abdominal ultrasound (US) and computed tomography (CT), as well as of various clinical factors related to LI, using univariate and multivariate methods. LI occurred in 4.9% of all patients (99/2,016) and in 3.0% of those who, if LI were disregarded, would have been included in clinical stages I and II. In multivariate analysis the presence of LI was significantly associated with splenic involvement or infradiaphragmatic involvement, absence of mediastinal involvement, serum alkaline phosphatase (SAP) level over 230 units/l, and age over 40 years. We used these factors to define a risk score for LI. LI is very rare in patients who would otherwise be in clinical stages I or II, but knowledge of LI is important because it has therapeutic consequences. With our risk score, liver biopsy is indicated for approximately one quarter of these patients otherwise in clinical stages I or II.

Adolescent↗
PubMed2000

Poor clinical outcome of patients with Hodgkin's disease and elevated interleukin-10 serum levels. Clinical significance of interleukin-10 serum levels for Hodgkin's disease.

Interleukin (IL)-10 is a pleiotropic cytokine with potent inhibitory effects towards T(H)-1 cells. IL-10 inhibits secretion of IL-2 and interferon (IFN)gamma by T cells and downregulates major histocompatibility complex antigens. A variety of tumor cells secrete IL-10, which can inhibit growth of tumor-specific cytotoxic T cells. IL-10 expression has also been detected in B-cell lymphomas and Hodgkin's disease (HD), and it has been suggested that the cytokine is involved in the pathogenesis of these tumors. We analyzed levels of IL-10 in pretreatment sera of 64 patients with HD and healthy controls using a sensitive enzyme-linked immunosorbent assay. Patients with biopsy-proven HD were enrolled in trials of the German Hodgkin Study Group (GHSG). Elevated IL-10 levels were detected in the sera of nine patients with HD (14.1%) (range 4.5-225.6 pg/ml with a mean of 61.5 pg/ml). IL-10 was not detectable in a control population of healthy volunteers (n =90). Multivariate analyses revealed a significant correlation between elevated IL-10 levels and higher age (over 45 years) but not with any other factors defined by the international prognostic factor score. Patients with elevated IL-10 levels had a significantly lower freedom from treatment failure rate as detected in univariate and multivariate tests. Thus, IL-10 may serve as an independent prognostic factor for HD patients.

Adolescent↗
PubMed2000

Perioperative treatment with filgrastim stimulates granulocyte function and reduces infectious complications after esophagectomy.

We investigated the effects of recombinant G-CSF (Filgrastim) on the function of neutrophils and the rate of infectious complications in an open-label, nonrandomized study of patients with esophageal cancer undergoing esophagectomy. In this single-center phase-II trial 20 sequential patients (19 evaluable) received Filgrastim at standard doses (300 microg or 480 microg) subcutaneously for 2 days prior to and up to 7 days after surgery. The phagocytotic activity of neutrophils and the oxidative burst in the study group and in an experimental control group (n=27) were measured on days -2, 2, and 10. Neutrophil function was enhanced in the Filgrastim-treated group by factor 1.2 for phagocytosis (p=0.016) and 1.4 for oxidative burst (p)=0.154). Leukocyte counts increased from 7.6 x 10(9)/l (day -2) to a maximum of 45 x 10(9)/l on day 6. No infection was reported in the study group (mean age 59.7 years; 13 men, seven women) up to 10 days after surgery. In contrast, 23 patients (29.9%) in a historical control group (mean age 56 years; 67 men, ten women) treated at the same center developed infections within the first 10 days (p = 0.008). In addition, no postoperative deaths occurred in the study group, compared with 9.1% in the group of historical controls. Thus, in this study, administration of Filgrastim stimulated neutrophil function in patients undergoing esophagectomy, and it might be effective in reducing infectious complications related to the surgical procedure.

Adult↗
PubMed2000

Detection of Isospora belli by polymerase chain reaction using primers based on small-subunit ribosomal RNA sequences.

The aim of the present study was to use small-subunit (SSU)-rRNA sequences of Isospora belli to design specific primer pairs and a hybridization probe for the detection of Isospora belli in human samples by PCR and Southern blot hybridization. PCR amplification with the primer pairs produced correct DNA fragments with target DNA from samples of Isospora belli-infected patients and from cloned SSU-rRNA of Isospora belli. The nature of the PCR products was confirmed by Southern blot hybridization. No amplification was seen with template DNA extracted from other parasites. Although Isospora belli infections can be easily diagnosed using light microscopy, molecular-based techniques may prove useful as an additional diagnostic tool.

Animals↗