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Biomedical subjects

E Thiel

Publications and source records attributed to E Thiel.

At least 91 records · Page 5Linked to original sources
PubMed2000

Detection of immunoglobulin heavy chain genes rearrangements in B-cell leukemias, lymphomas, multiple myelomas, monoclonal and polyclonal gammopathies.

Polymerase chain reaction (PCR) based assays were found to be a realistic alternative to Southern blot hybridization for the assessment of clonal immunoglobulin heavy chain gene rearrangements. However, a comparison of the different PCR based studies reveals considerable variation in experimental design and marked differences in the reported results. This study compared different single- and double-step PCR assays relying on various FR3, FR2, FR1 and JH based primers for the detection of B cell clonality in acute lymphoblastic leukemias (ALL), non-Hodgkin's-lymphoma (NHL), multiple myeloma (MM), monoclonal gammopathies of unknown significance (MGUS) and three polyclonal gammopathies (PG). The highest monoclonality rate was observed using seminested CDR-III region amplification. This method achieved a monoclonal product in 6 of 13 pro-B ALL 21 of 29 c-ALL, 7 of 8 pre-B-ALL, 18 of 21 B-ALL, 14 of 17 B-NHL (intermediate or high grade) with bone marrow involvement, 0 of 9 B-NHL without bone marrow involvement, 9 of 9 low grade B-NHL (immunocytoma and including chronic lymphocytic leucemia), 13 of 19 MM, 2 of 9 MGUS, and 0 of 3 PG. Additional monoclonality was detected with nested CDR I PCR in 1 pro-B-ALL, 1 c-ALL, and 2 MM. CDR III IgH PCR has been confirmed as an efficient method for determining clonality in B-cell neoplasias. Some additional monoclonal products can be seen with CDR I-based PCR. Detection of monoclonality depends on the maturation grade of the neoplastic B-cell population.

Bone Marrow Cells↗
PubMed2000

Analysis of Wilms tumor gene (WT1) expression in acute leukemia patients with special reference to the differential diagnosis between eosinophilic leukemia and idiopathic hypereosinophilic syndromes.

Continuous Wilms' tumor gene (WT1) expression is a typical feature of leukemic blasts in AML, ALL, and blast crisis CML patients. It is easily detectable by a variety of RT-PCR protocols, which differ mainly in their sensitivity. The nuclear WT1 protein can be found in blasts of approximately 50-60% of acute leukemia patients at diagnosis. Conversely, WT1 is only transiently expressed in normal hemopoiesis. Early CD34+ hemopoietic progenitors express WT1, whereas no WT1 mRNA transcripts can be found in mature blood cells and differentiation-induced committed CD34- progenitors. As a powerful complementary diagnostic tool, testing for WT1 expression can be helpful to discriminate between eosinophilic leukemia (EoL) patients and patients with idiopathic hypereosinophilic syndromes. Conflicting data about the usefulness of testing for WT1 expression to monitor minimal residual disease (MRD) in treated leukemia patients will be discussed. Finally, research strategies to circumvent shortcomings in detecting leukemia-associated WT1 expression will be outlined.

Acute Disease↗
PubMed1999

Differential effects of a stem cell factor-immunoglobulin fusion protein on malignant and normal hematopoietic cells.

We genetically connected the extracellular domain of human stem cell factor to the Fc-portion of human IgG1. The chimeric recombinant stem cell factor IgG1 fusion protein (rSCF-IgG1) had an apparent approximately Mr 190,000 and consisted of three identical covalently linked subunits. It specifically bound to c-kit and the high affinity Fc gamma receptor, respectively. Liquid phase rSCF-IgG1 was, on a molar basis, about eight times more potent than native human rSCF in stimulating the proliferation of c-kit-positive leukemic cell lines and of nonmalignant CD34-positive hematopoietic progenitor cells. Although the effective dose conferring half maximum of [methyl-3H]thymidine uptake by liquid phase and solid phase-bound rSCF-IgG1 were comparable, the plateau level of [methyl-3H]thymidine uptake by malignant cells was decreased by the latter, whereas proliferation of nonmalignant progenitor cells was supported. Liquid phase rSCF-IgG1 had a 2-fold increased potential to maintain primitive nonmalignant progenitor cells in stroma-free long-term culture compared with rSCF. Liquid phase rSCF-IgG1 caused enhanced and prolonged receptor phosphorylation and a more rapid down modulation of c-kit. Our data support the concept that solid phase-attachment of rSCF-IgG1 is sufficient for alteration of biological function and that rSCF-IgG1 partially blocks SCF-stimulated malignant cell growth while supporting normal progenitor cells.

Animals↗
PubMed1999

[Treatment of adult acute lymphoblastic leukemia].

In patients with adult ALL, substantial progress has been made in the past 20 years. At present a cure rate of 30-40% can be achieved and varies in defined subgroups between 10-51%. ALL does not represent an uniform disease but is formed by biologic subentities, which differ in their natural history, clinical presentation and prognosis. A comprehensive diagnostic examination, including morphology, cytochemistry, immunology, cytogenetic and molecular genetic analysis is a precondition for prognostic assessment and therapeutic stratification. The basic principle of ALL treatment is a combination chemotherapy with sequential administration of induction, consolidation and maintenance therapy. Bone marrow transplantation has become an important part of the treatment strategy and is performed in patients with high risk. In the subgroup of T-ALL a significant progress has been made in the last years with survival rates of 40-50%. In B-ALL the results have been greatly improved to 48-51% by introduction of a specific treatment strategy. However, the results (about 30%) stagnate for the total group of B-lineage-ALL (common ALL, pre-B-ALL, pro-B-ALL). Patients with B-lineage-ALL can be subdivided in a high and low risk group according to the presence of risk factors (age, white blood cell count, time to achieve a complete remission, pro-B-ALL and the translocations t[4;11], t[9;22]). The outcome of the subgroup of adult pro-B-ALL has been substantially improved (50%). An increase of treatment results (20%) appears in outlines for patients above 50 years. The Ph/bcr-abl positive ALL has in spite of improved complete remission rates (60-70%) consistently unfavourable survival rates (10%).

Adult↗
PubMed1999

Elevated serum thymidine kinase levels identify a subgroup at high risk of disease progression in early, nonsmoldering chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) shows a remarkably heterogeneous clinical outcome; survival ranges from several months in advanced stages to more than 10 years in early stages. The Binet and Rai staging systems distinguish three major prognostic subgroups, but do not accurately predict the individual risk of disease progression in early CLL (Binet stage A or Rai stage 0 to II). Because most newly diagnosed CLL patients present with early disease, it seems desirable to search for additional prognostic factors to identify early CLL patients at high risk of rapid progression. It has been shown that elevated serum thymidine kinase (s-TK) levels predict disease progression in CLL. Therefore, this study aimed to assess the prognostic value of s-TK in 122 previously untreated patients with Binet stage A CLL (mean age +/- SD, 58.7 +/- 8.5 years). In univariate analyses, 18 of the 22 parameters investigated predicted progression-free survival (PFS). In a stepwise multiple regression analysis, only three parameters provided independent prognostic information on PFS: s-TK greater than 7.1 U/L; presence of lymphadenopathy; and white blood cell (WBC) count greater than 75, 000/microL. When added to the classification of smoldering versus nonsmoldering CLL, s-TK levels separated two groups within the group of nonsmoldering stage A patients: patients with s-TK values greater than 7.1 U/L had a median PFS of 8 months, whereas patients with s-TK values </= 7.1 U/L expected a much longer PFS (49 months; P <. 001), similar to smoldering CLL (42 months). The results demonstrate that s-TK is a prognostic parameter that adds independent prognostic information to the definitions of smoldering and nonsmoldering CLL in Binet stage A.

Adult↗
PubMed1999

Induction of tyrosinase-reactive T cells by treatment with dacarbazine, cisplatin, interferon-alpha +/- interleukin-2 in patients with metastatic melanoma.

We have shown the presence of tyrosinase-reactive T cells in the peripheral blood of melanoma patients, who had been in remission after treatment with IL-2-containing regimens. In this consecutive study, we analyzed the T-cell response to various peptides derived from tyrosinase in serial blood samples obtained from 7 stage-IV melanoma patients before, during and following treatment. All patients were treated within a randomized trial (EORTC 18951) with cisplatin (CDDP), dacarbazine (DTIC), interferon-alpha (IFN-alpha) +/- interleukin-2 (IL-2). Using an ELISPOT assay detecting peptide-specific IFN-gamma release, we measured the T-cell response to 4 different HLA class I-binding peptide epitopes derived from tyrosinase containing an HLA-A2.1-, HLA-A24- or HLA-B44-binding motif in peripheral-blood mononuclear cells (PBMC). In one patient, tyrosinase-reactive T cells were detected before therapy. In 4 out of 7 patients, tyrosinase-reactive T cells against both HLA-A2.1-binding peptides and the B44-binding peptide became detectable at frequencies of up to 30 in 5 x 10(5) lymphocytes following treatment. These patients received CDDP, DTIC and IFN-alpha, 2 of them without IL-2 and 2 with IL-2, resulting in one complete remission and 3 partial remissions. Two patients relapsed 8 and 9 months after treatment. At the time of relapse, no T cells reactive with tyrosinase were detectable. Our results show that high frequencies of tyrosinase-reactive T cells in the peripheral blood of melanoma patients can be induced by chemotherapy in combination with IFN-alpha, regardless of concomitant IL-2 administration.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Culturing human umbilical cord blood: a comparison of mononuclear vs CD34+ selected cells.

We compared UCB mononuclear cells (MNC) with CD34+ selected cells in a serum-free static culture system. Cell number proliferation of MNCs was inferior to CD34+ selected cells. MNCs, however, showed a substantial increase from 0.94% CD34+ cells on day 0 to 5.8% on day 7, whereas in the CD34+ selected samples the CD34+ cell content declined continously from 62.2% on day 0 to 27.7% on day 7. The number of CFU-GM increased during culture of both cell fractions. Here, only the MNCs showed a substantial increase in clonogenicity on day 7 and day 14 to 11.1- and 4.1-fold input, respectively. This expansion of the CD34+ progenitor cell pool in the MNCs fraction was at least in part attributable to T cells, since the physical abrogation of T cells blocked this effect. Refeeding and reseeding of cells on day 7 had stimulating effects especially on the CD34+ cells, where cell number proliferation increased from 16.3-fold without to 58.1-fold on day 14. Also, we could find sporadic chromosomal aberrations in four of 100 metaphases examined after 7-20 days of ex vivo expansion. The significance of this observation needs to be clarified in a larger series.

Antigens, CD34↗
PubMed1999

CD82 (KAI1), a member of the tetraspan family, is expressed on early haemopoietic progenitor cells and up-regulated in distinct human leukaemias.

CD82 (KAI1) is a member of the tetraspan transmembrane protein family which has been cloned from lymphoblastoid variant cell lines. However, a role for CD82 in early normal and malignant haemopoiesis has not yet been characterized. We studied the CD82 expression in 33 normal donor samples and 98 leukaemias by fluorescence activated cell sorting (FACS) and reverse transcriptase polymerase chain reaction (RT-PCR). We demonstrated that CD82 was moderately expressed in the vast majority of normal granulocytes and monocytes. In contrast, only about one third of the peripheral blood lymphocytes were weakly CD82 positive (CD82+). Interestingly, judgement of the CD82 transcription and expression in various leukaemias revealed that CD82 was overexpressed in chronic myeloid leukaemia (CML) patients in accelerated or blastic phase (CML-AP/BP) as well as in acute myeloid leukaemia (AML) and chronic lymphocytic leukaemia (CLL) patients. Analysis of AML patients with CD34+/CD82+ blasts prompted us to expand our studies on haemopoietic CD34+ progenitor cells. Intriguingly, 84-95% of the CD34+ cells isolated from healthy bone marrow, cord blood or peripheral blood were highly CD82+. CD82 was abundantly expressed on primitive as well as on committed haemopoietic progenitor cells. After in vitro induction of myeloid differentiation in CD34+ peripheral blood progenitor cells (PBPC), the expression of CD82 decreased to levels similar to those found on peripheral blood granulocytes. These observations suggest for the first time a role for CD82 in normal and malignant haemopoiesis.

Antigens, CD↗
PubMed1999

Carboxypeptidase G2 rescue in a 79 year-old patient with cranial lymphoma after high-dose methotrexate induced acute renal failure.

A 79 year-old female patient presented with immunoblastic B-cell lymphoma of the ethmoidal sinuses and destruction of the anterior cranial fossa. After 3 cycles of high-dose methorexate (HD-MTX) MTX serum level remained elevated and creatinine serum levels raised. The patient received Carboxypeptidase G2 (CPG2) intravenously. Within one hour the MTX serum level decreased to <1 micromol/l as determined by high pressure liquid chromatography (HPLC). The patient recovered without significant toxicity and attained a long lasting ongoing (>14 months) complete remission. In this case we were able to demonstrate that rescue from HD-MT nephrotoxicity by CPG2 is also safe and effective in patients with advanced age with impaired renal function. With the help of CPG2, sufficient and potentially curative therapy with HD-MTX may also be provided to patients with a high risk of renal failure.

Acute Kidney Injury↗
PubMed1999

In the queue for coronary artery bypass grafting: patients' perceptions of risk and 'maximal acceptable waiting time'.

OBJECTIVES: To elicit patients' maximal acceptable waiting times (MAWT) for non-urgent coronary artery bypass grafting (CABG), and to determine if MAWT is related to prior expectations of waiting times, symptom burden, expected relief, or perceived risks of myocardial infarction while waiting. METHODS: Seventy-two patients on an elective CABG waiting list chose between two hypothetical but plausible options: a 1-month wait with 2% risk of surgical mortality, and a 6-month wait with 1% risk of surgical mortality. Waiting time in the 6-month option was varied up if respondents chose the 6-month/lower risk option, and down if they chose the 1-month/higher risk option, until the MAWT switch point was reached. Patients also reported their expected waiting time, perceived risks of myocardial infarction while waiting, current function, expected functional improvement and the value of that improvement. RESULTS: Only 17 (24%) patients chose the 6-month/1% risk option, while 55 (76%) chose the 1-month/2% risk option. The median MAWT was 2 months; scores ranged from 1 to 12 months (with two outliers). Many perceived high cumulative risks of myocardial infarction if waiting for 1 (upper quartile, > or = 1.45%) or 6 (upper quartile, > or = 10%) months. However, MAWT scores were related only to expected waiting time (r = 0.47; P < 0.0001). CONCLUSIONS: Most patients reject waiting 6 months for elective CABG, even if offered along with a halving in surgical mortality (from 2% to 1%). Intolerance for further delay seems to be determined primarily by patients' attachment to their scheduled surgical dates. Many also have severely inflated perceptions of their risk of myocardial infarction in the queue. These results suggest a need for interventions to modify patients' inaccurate risk perceptions, particularly if a scheduled surgical date must be deferred.

Adult↗
PubMed1999

Expression of the C-kit receptor (CD117) is a feature of almost all subtypes of de novo acute myeloblastic leukemia (AML), including cytogenetically good-risk AML, and lacks prognostic significance.

Because of conflicting reports on the prognosis of patients with c-kit receptor positive AML and lacking correlations with cytogenetic analyses, we prospectively evaluated the c-kit receptor expression in 917 AML patients (750 adult patients; 167 children) using flow cytometry and compared the results to the immunophenotype, morphological and cytogenetic findings as well as clinical outcome. Expression of the c-kit receptor was present in 63% of all AML investigated. Among these an immature immunophenotype was more frequent and 30% had a CD34+/CD15- and 37% a CD34+/CD14- phenotype, whereas only 9% and 10% showed these phenotypes in the c-kit receptor negative group, respectively. C-kit receptor expression ranged average in M0 and M1 subtypes (69% versus 70%) but was less pronounced among M5 subtypes (21%). Results of karyotyping were available in 280 patients. C-kit receptor expression occurred in 37 of 42 (88%) patients with favorable cytogenetic abnormalities such as t(8;21), t(15;17) or inv(16) which exceeded the expression rate in patients with intermediate risk, poor risk or other abnormalities. Information about the clinical outcome was available in 228 patients treated according to the protocols of two German multicenter trials (AML-BFM, AMLCG). We found no difference of CR-rate or event-free survival (EFS) in adults with or without c-kit receptor expression. Children with c-kit receptor negative AML had a lower CR-rate and EFS, but also a lower median age and a higher frequency of M5 subtype as compared to children with c-kit receptor expression. In conclusion, analysis of c-kit receptor expression may help to identify phenotypically immature AML but fails to identify myeloid differentiation of leukemic blasts in approximately one third of patients. We found no evidence of an adverse prognosis in AML patients with c-kit receptor expression. Analysis for c-kit receptor expression does not appear to add information to established prognostic parameters in AML.

Adolescent↗
PubMed1999

Efficacy and safety of simultaneous immunomagnetic CD34+ cell selection and breast cancer cell purging in peripheral blood progenitor cell samples used for hematopoietic rescue after high-dose therapy.

We have established a new simultaneous positive/negative selection procedure using the Baxter Isolex 300i system. We tested its tumor cell (TC) purging efficacy by tumor contamination tests ex vivo and its safety in a group of 17 breast cancer (BC) patients by measuring hematopoietic recovery after high-dose (HD) therapy and autologous stem cell rescue with the selected cells. Tumor contamination tests resulted in a TC depletion of 4.1-6.0 log steps. The CD34+ cell yield in this experimental setting was 38.9-91.5%, and the CD34+ cell purity was 86.0-96.0%. In a group of 17 BC patients (5 high-risk adjuvant, > or = 10 lymph nodes positive, and 12 metastatic), we processed leukapheresis products (LPs) by simultaneous positive/negative selection. In these clinical samples, the mean CD34+ cell yield was 56.2% (range, 14.0-80.1%), and the CD34+ cell purity was 94.5% (range, 69.0-99.8%). Additionally, we screened samples of the patients' LPs before and after the purging procedure for contaminating TC by immunocytochemistry. In 15 of 17 tested cases, TCs were detectable prior to the purging procedure. After the procedure, we could not detect residual TCs in 16 of 17 cases. In one case, we found a highly reduced number of TCs. Furthermore, we evaluated the times for hematopoietic reconstitution in a group of five BC patients in the high-risk adjuvant situation who underwent HD chemotherapy and hematopoietic rescue with positive/negative selected stem cells and compared it with our own data from 10 BC patients who, after identical HD therapy, received only positively selected CD34+ cells and 14 patients who, after identical HD therapy, received autografts purged by incubation with toxic ether lipids (ET-18-OCH3). In all groups, a leukocyte count of >2000 cells/microl was reached at day +10. A platelet count of > 50,000 cells/microl was reached at day +12 in the ET-18-OCH3 group and at day +14 in the other two groups. Furthermore, 12 patients with metastatic disease rescued with positive/negative selected stem cells after HD therapy also showed fast and comparable hematopoietic recovery. The new simultaneous immunomagnetic positive/negative selection using a closed system is effective and safe. Processing LPs leads to a similar CD34+ cell yield, a higher TC depletion compared to standard CD34+ cell selection, and no delay in hematopoietic recovery.

Antigens, CD34↗
PubMed1998

[Clubbed fingers and arthralgia as a reversible paraneoplastic syndrome (Pierre-Marie-Bamberger syndrome) in non-small-cell bronchial carcinoma].

HISTORY AND CLINICAL FINDINGS: During chemotherapy for a non-small-cell bronchial carcinoma with metastasis to the right femur (previously locally excised), a 34-year-old man suddenly developed severe, lasting joint pain in the ankle, knee, elbow and wrist without signs of increased warmth or swelling of these joints. At the time of diagnosis clubbed fingers had been noted. INVESTIGATIONS: Radiography of the hands showed bilateral periosteal hyperostoses. Computed tomography of the thorax revealed tumor progression. DIAGNOSIS, TREATMENT AND COURSE: The triad of clubbed fingers, periosteal hyperostoses and arthralgia/arthritis with the pulmonary findings established the diagnosis of hypertrophic pulmonary osteoarthritis (HPO; Marie-Bamberger syndrome). Initially there had merely been the signs of the much more frequent incomplete form with only the clubbed fingers, the complete form developing with progression of the disease during chemotherapy, joint pains dominating the symptoms. After right upper lobectomy (primary adenocarcinoma) the joint pains ceased and the finger clubbing regressed. CONCLUSIONS: Only 10% of non-small-cell bronchial carcinomas are associated with HPO. Conversely, such a tumor is found in 90% of HPO of recent onset and should therefore be sought of when searching for the primary tumor. The signs of HPO are reversible if the underlying disease is adequately treated.

Adult↗
PubMed1998

Immunophenotypic and genotypic features, clinical characteristics, and treatment outcome of adult pro-B acute lymphoblastic leukemia: results of the German multicenter trials GMALL 03/87 and 04/89.

In contrast to childhood acute lymphoblastic leukemia (ALL), the cell-biological features, clinical characteristics, and treatment outcome of CD10(-) pro-B ALL have not yet been determined in larger series of adult patients. Therefore, we studied 57 adult patients with newly diagnosed pro-B ALL (median age, 30 years) enrolled in two consecutive German multicenter ALL studies (03/87 and 04/89). Extensive immunophenotypic characterization of leukemic blasts could be performed on all patients, whereas adequate cytogenetic data were available in 33 cases and molecular studies in 18 cases, using reverse transcription-polymerase chain reaction to detect MLL-AF-4 transcripts. Twenty-two patients demonstrated a t(4;11)(q21;q23) and/or MLL-AF-4 rearrangements, and 6 patients had other structural abnormalities, including a t(9;22)(q34;q11) (N = 2). Nine patients had a normal karyotype. Patients with 11q23 abnormalities tended to be younger (median age, 29 years) and were characterized by male predominance (64%), hyperleukocytosis (median leukocyte count, 168 x 10(9)/L), and a frequent coexpression of CD65s (64%) as compared with patients with other cytogenetic abnormalities or a normal karyotype. Twelve of 16 (75%) pro-B ALL patients in study 03/87 and 30 of 41 (73%) in study 04/89 achieved a complete remission (CR). Sixteen of 30 patients in study 04/89 remain in continuous CR (CCR) in contrast to only 2 of 12 patients in study 03/87. Interestingly, all 7 patients treated with high-dose cytarabine and mitoxantrone as consolidation in study 04/89 remain alive and leukemia-free. One patient in study 03/87 and 8 in study 04/89 underwent autologous (N = 2) or allogeneic (N = 7) bone marrow transplantation (BMT). The median remission duration was 420 days for patients in study 03/87 and has not yet been reached in study 04/89. The median survival time of all pro-B ALL patients was 571 days in study 03/87 and 747 days in study 04/89. Among the 22 patients with a t(4;11) and/or MLL-AF-4 rearrangements, 17 achieved a CR and 8 are still in CCR, of whom 4 underwent an allogeneic BMT. Remission duration and overall survival did not differ significantly between pro-B ALL patients with 11q23 abnormalities and those with a normal karyotype or other structural abnormalities. These data indicate that intensification of postremission treatment may improve the prognosis of adult pro-B ALL, including patients with a t(4;11).

Adolescent↗