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Biomedical subjects

W D Ludwig

Publications and source records attributed to W D Ludwig.

231 records · Page 13Linked to original sources

Use of monoclonal antibodies as a diagnostic tool in human leukemia. I. Acute myeloid leukemia and acute phase of chronic myeloid leukemia.

Various monoclonal antibodies (mAbs) detecting certain different epitopes on myeloid cells (VIMD5, D5 D6, OKM1, Leu-M3, VIEG4, OKIa 1) have been used in combination with conventional markers (antihuman myeloid hetero-antiserum, FcIgG-receptors, C3d-receptors) to further define the phenotypic heterogeneity of myeloid leukemia. Subsequent leukemic samples from previously untreated patients with acute myeloid leukemia (AML) (51 adults, 24 children) and from nine adult patients in the acute phase of chronic myeloid leukemia (CML-BC) were studied. It was possible to demonstrate quantitative differences in the expression of antigens on the various leukemia subtypes which could be exploited for diagnosis. Furthermore our results revealed that there is a very close correlation between the different surface phenotypes and the types morphologically assessed according to FAB-criteria.

Adult↗

Expanded T gamma cell populations with the morphology of large granular lymphocytes -- I. Immunological, clinical and morphological characterization.

Lymphocytes from two patients with T gamma cell proliferations displaying the morphology of large granular lymphocytes (LGL) were characterized in terms of cell marker phenotyping and immunologic functions. In both patients, the lymphocytes were positive for E-R, HuTLA, OKT5, OKT8, OKT11, OKM1, VEP13, Leu1, Leu2a, Lyt2 and Lyt3 and were negative for Tmu, Tar, SIg, BA1, BA2, EM-R, C3d-R, C3b-R, OKT6, OKT9, Leu3a, OKIa1 and TdT. In addition, investigations for T411, T811 and M522 in patient 1 yielded positive results. There were differences in the phenotype of the two patients with regard to the reactions with OKT3, OKT10 and VEP10. While, in patient 1, OKT3 was very pronounced and OKT10 and VEP10 were completely negative, OKT10 and VEP10 were very pronounced in patient 2, whereas OKT3 was positive only in a very small percentage of cells. Though the lymphocytes in both patients were potent effectors of NK and K functions (patient 2 more strongly than patient 1) and a noticeably reduced mitogen response was shown to PHA, Con A and zinc, patient 1 showed a distinct suppression of allogenic and autologous B cell response to transformation into ISC, coinciding with the clinical observation of a hypogammaglobulinemia; neither B cell suppression nor dysgammaglobulinemia was seen in patient 2. The results are discussed with regard to other comparable T gamma proliferations reported in the literature.

Aged↗

Rapid cellular regulation of D-glucose transport in cultured neural cells.

Previous studies have revealed two different kinds of regulation of glucose utilization in cell lines derived from the nervous system (Keller et al., 1981). We found glucose metabolism of C-6 glioma cells to be limited and regulated by membrane transport. In contrast, glucose utilization of C-1300 neuroblastoma (N2A) cells was limited by the known regulatory enzymes of the Embden-Meyerhof pathway. Under the given experimental conditions the "membrane-limited" C-6 glioma cells were characterized by periodically changing glucose transport rates and very low intracellular glucose concentrations, which remained constant in spite of widely differing transport rates. These findings suggest the close functional coupling between transport and phosphorylation required for the regulation of glucose transport by cellular metabolic needs.

Animals↗

[Classification of AML by morphologic, immunologic and cytogenetic criteria. Review with reference to subtypes in the AML-BFM-87 study].

The current FAB classification of acute myelogenous leukemia (AML) by morphologic, immunologic and cytogenetic features is described and the incidence of subtypes and variant forms of AML in study AML-BFM-87 is given. In general, lymphoblastic or myeloid blast populations can be identified by morphologic, cytochemical and immunologic parameters, while immunophenotyping facilitates diagnosis in biphenotypic leukemia. Furthermore, the AML subtypes M0 and M7 (defined in 1985 and 1991) can only be ascertained by the presence of lineage-associated markers. Whereas chromosome aberrations provide an insight into the neoplastic process and assure diagnosis. Thus, next to morphologic findings, immunologic and cytogenetic studies are essential for a definite diagnosis of AML.

Antineoplastic Combined Chemotherapy Protocols↗

[Definition of malignant histiocytosis and large cell anaplastic (Ki-1) lymphoma in children].

Cells belonging to the mononuclear phagocytic system may give rise to a wide variety of proliferative disorders. These neoplastic or reactive diseases of monocytes, histiocytes and macrophages are still poorly understood, both from a biological, clinical and pathological point of view. In 1984 a new type of non-Hodgkin's lymphomas has been described, which recently was termed large cell anaplastic lymphoma (LCAL). Since both "true" malignant histiocytosis (MH) and LCAL display some clinico-pathological similarities, we reevaluated eleven children with the primary diagnosis of MH, who entered the multicentric therapy study DAL-HX 83. On the basis of the typical morphology LCAL and not MH has been diagnosed in all cases. The Ki-1 (CD 30) positive tumor cells of LCAL can display different phenotypes, either T-lymphoid, B-lymphoid, histiocytic or neither of them (O-phenotype). Therefore we investigated the lineage specificity of tumor cells in 15 paediatric patients with LCAL. Tumor cells of histiocytic origin could be demonstrated in only one of them. In 7 patients the neoplastic cells were of T cell and in the remaining 7 cases of non T/non B cell (O) phenotypes, confirming the extreme rarity of MH in children. It is our opinion that MH and LCAL seem to be different diseases not only nosologically but also clinico-pathologically. In the multicentric therapy studies NHL-BFM 81 and NHL-BFM 83 the frequency of LCAL in childhood is compared to all other subentities at 3%.

Adolescent↗

[Incidence, clinical markers and prognostic significance of immunologic subtypes of acute lymphoblastic leukemia (ALL) in children: experiences of the ALL-BFM 83 and 86 studies].

In the therapy studies ALL-BFM 83 and 86, immunophenotyping of ALL by monoclonal antibodies was performed in a total of 1162 protocol patients (ALL-BFM 83 n = 578; ALL-BFM 86 n = 584). Both studies yielded similar results with respect to the incidence of immunological subtypes: CD10-negative pre-pre-B ALL (ALL-BFM 83: 3.6%; ALL-BFM 86: 5.3%), common ALL (80.1%; 77.9%), B-ALL (1.9%; 2.8%), pre-T/T-ALL (13.9%; 13.5%). Leukemic cells of 3 patients in the ALL-BFM 83 study lacked lymphoid and myeloid antigens (acute unclassifiable leukemia, 0.5%), and 3 patients in the ALL-BFM 86 study exhibited different blast populations with expression of either myeloid or lymphoid features (acute mixed-lineage leukemia, 0.5%). Coexpression of myeloid antigens (CD13 and/or CD33 and/or CDw65) on lymphoblasts (My-positive ALL) was identified in 35 of the 570 (6.1%) protocol patients prospectively analyzed in the ALL-BFM 86 study. The following associations were observed between the immunological subtype and the clinical risk factors: median age (years)-pre-pre-B 3.0, common 4.3, B- 7.9, pre-T/T-ALL 8.5 (pre-pre-B, common vs. pre-T/T-ALL p = 0.05); median leukocyte counts (x 10(9)/l)-pre-pre-B 80, common 9.1, B- 12.3, pre-T/T-ALL 68.1 (common, B- vs. pre-pre-B, pre-T/T-ALL p less than 0.05). The prognostic relevance of the immunophenotype was evaluated on the basis of the therapeutic results obtained in the ALL-BFM 83 study. A significant difference in the remission rate was only recognizable between patients with common ALL (99.1%) and those with pre-T/T-ALL (93.7%, p less than 0.001). After a median follow-up of 54 months, the probability of event-free survival is 71% for pre-pre-B ALL, 67% for common ALL, 56% for pre-T/T-ALL and 27% for B-ALL (common vs. B-, pre-T/T-ALL p less than 0.001), the prognosis in patients with pre-pre-B and common ALL being markedly influenced by the initial leukocyte counts and the age.

Antigens, CD↗

[The role of CD95 (APO-1/Fas) mutations in lymphoproliferative and malignant lymphatic diseases].

CD95 (APO-1/Fas)-mediated apoptosis plays a major role in normal lymphocyte regulation. CD95 mutations cause a benign autoimmune lymphoproliferation syndrome (ALPS) in mice and humans. CD95 is mutated in some de novo T-lineage acute lymphoblastic leukemia of childhood and these mutations might be of biological significance. The resistance toward CD95-mediated apoptosis observed in most B-lineage ALL is not caused by mutations of CD95. CD95 mutations have been associated with Hodgkin's and Non-Hodgkin's lymphoma and have been described in multiple myeloma. The relevance of CD95 mutations for chemoresistance of ALL requires further study.

Animals↗

[Acute myeloid leukemia in children with Down syndrome].

Forty-four children, aged between 0.4 and 16.2 years (median 2.0 years) with Down's syndrome and acute myelogenous leukemia (AML) including subacute megakaryoblastic leukemia (M7) were diagnosed between 1980 and 1986 (group 1, n = 16) or between 1987 and 1992 (group 2, n = 28). The leukemic blasts from Down's syndrome patients often proved difficult to classify. In group 1 the most frequent diagnoses were FAB M5 (6 pts.), M6 (3 pts.), in 3 patients the morphological diagnosis of M7 can retrospectively be assumed. In group 2, 15 of 28 patients were classified as M7, in 3 patients based on morphology alone, and in the other 12 patients confirmed by immunophenotyping or biopsy. The other children in group 2 were classified as: FAB M0 (3 pts.), M1 (1 pt.), M4 (2 pts.), M5 (2 pts.), M6 (4 pts.), M6/M7 (1 pt.). Initially, the latter and 10 of the patients with M7 presented with < 30% of blasts in the bone marrow. Karyotyping in 12 of 13 children frequently revealed numeric abnormalities, particularly trisomies involving chromosomes 8 (n = 6), 11 (n = 3), 21 (n = 3) and 14 (n = 1) in addition to the constitutional + 21c. Six patients in group 1 received no specific treatment, while 10 children were treated according to the protocols AML-BFM-78 or -83. Four of them are still alive for more than 5 years, two others died from infections in remission after 1.0 and 3.8 years. Fourteen of the 28 patients in group 2 did not receive any chemotherapy (10 with M7), and subsequently died.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Concept and interim result of the ALL-BFM 90 therapy study in treatment of acute lymphoblastic leukemia in children and adolescents: the significance of initial therapy response in blood and bone marrow].

In the ongoing trial ALL-BFM 90 for the treatment of childhood non-B cell acute lymphoblastic leukemia (ALL) 1468 unselected patients (pts) were enrolled from 84 centers in Germany and Switzerland from 4/90 to 12/93. Based on the results of the previous trial ALL/NHL-BFM 86 this treatment program focused especially on therapy modifications for average (MRG) and high risk (HRG) pts, on the evaluation of therapy response for prognosis, and on the identification of high risk pts by molecular genetics. For average risk pts consolidation therapy was intensified by the addition of L-asparaginase (L-ASP) on a randomized basis. In HRG induction and consolidation therapy was modified by introduction of early intensification elements that had proved to be effective in relapsed pts. This patient group was randomized for the evaluation of the effects of G-CSF administered in the intervals between the intensification elements. Distribution of the 1376 eligible pts into the three treatment arms SRG (standard risk), MRG, and HRG was as expected (17 pts not yet assigned): 385 pts (28.0%), 834 pts (60.6%), and 140 pts (10.2%), respectively. Treatment consisted of the 8-drug induction (Protocol I), consolidation (Protocol M), reinduction (Protocol II), and maintenance therapy (total therapy duration 24 months). The drug doses and combinations were only slightly modified compared to the previous study ALL-BFM 86 with the exception of the randomized L-ASP containing arm MRG-2 (Protocol M-A) and group HRG. Preventive cranial irradiation was reduced to 12 Gy and applied to MRG and HRG pts only. As in study ALL-BFM 86, the initial response to a 7-day exposure to prednisone and to the first intrathecal injection of MTX at diagnosis was evaluated at day 8 of treatment with regard to blast count in peripheral blood (PB). In addition, pts were now investigated for the presence of blasts in the bone marrow (BM) at day 15 of treatment to compare the prognostic power of both response parameters. Identification of translocation t(9; 22) and/or BCR-ABL rearrangement characterized a small subgroup of pts that were not detected by poor initial therapy response. These pts were enrolled in HRG for more intensive treatment including allogeneic bone marrow transplantation (BMT). After a median observation time of 22 months, the overall probability for event-free survival (p-EFS) is 82 +/- 2%. 11 pts (0.8%) died before complete remission (CR) was achieved, 15 pts (1.1%) died while in CR for reasons other than relapse.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

[NHL-BFM 90 therapy study in treatment of malignant non-Hodgkin's lymphomas in children and adolescents. Part 1: Classification and allocation to strategic therapy groups. BIF study group].

One of the goals of the study NHL-BFM 90 was to investigate the distribution and prognosis of the different subtypes of Non-Hodgkin's Lymphoma (NHL) in children and adolescents according to histological, cytomorphological and immunological characteristics. From 4/1990 to 12/1992, 346 patients (pts) (84 females, 262 males) were enrolled (median age: 9.1 years; range: 0.8-17.9 years). Histology was available from 290 pts (84%), cytomorphology from 155 (44%), and immunophenotyping from 245 (70%). Cases with L1 oder L2 cytomorphology according to the French-American-British Classification were classified as lymphoblastic lymphoma and those with L3 cytomorphology as Burkitt-Type lymphoma or acute B-cell leukemia (B-ALL) if a histological classification was not available. By means of the combined analysis of all three diagnostic criterias the classification of the NHL according to the updated Kiel-classification was possible in 312 cases: 49% were classified as Burkitt-type-lymphoma (incl. B-ALL), 22% als lymphoblastic lymphoma, 10% as large cell anaplastic lymphoma (LCAL), 6% as centroblastic lymphoma, only few cases were classified as NHL of other subtypes, 3 pts (1%) suffered from low grade malignant lymphomas, and in 34 pts (10%) the NHL was not further classified. Patients were stratified according to NHL-subentities in 3 branches (Non-B-NHL, B-NHL, LCAL) of different treatment modalities. The estimated probability of a 3-year event free survival (pEFS) was 88 +/- 2% for the whole group (follow up 7 to 40 months, median 23 months) while pEFS of different subtypes was: lymphoblastic lymphoma: 91 +/- 4%; Burkitt-type-lymphoma/B-ALL: 90 +/- 2%; centroblastic lymphoma: 94 +/- 6%, LCAL: 88 +/- 6%. We conclude that the stratification of treatment modalities in study NHL-BFM 90 according to biological entities provided patients of different NHL-subtypes an equal chance to survive event free. The efficacy of the treatment strategy for rare subtypes, however, is not evaluable yet.

Adolescent↗

Susceptibility of human leukemia to allogeneic and autologous lymphokine-activated killer cell activity: analysis of 252 samples.

The present study investigated the susceptibility of human leukemia cells to allogeneic lymphocytes with lymphokine-activated killer (LAK) activity from normal donors and autologous LAK activity from patients in complete remission. LAK activity was generated from peripheral-blood mononuclear cells cultured for 6 days with 1,000 U/ml recombinant interleukin-2 (IL-2). Cytotoxicity was evaluated using a standard 4-hour chromium release assay. Susceptibility of leukemic cells to LAK was defined on the basis of the mean Cr release in 52 samples of normal bone marrow cells. Using allogeneic LAK, we examined leukemic cells from bone marrow or peripheral blood of 252 patients [102 with acute myeloid leukemia (AML), 99 with acute lymphoblastic leukemia (ALL), 13 with chronic myelogenous leukemia in blast crisis (CML-BC) and 38 with chronic leukemias of various types]. A significant lysis could be detected in 62% of all leukemias tested (in 68% of AML, 60% ALL, 92% CML-BC, 39% chronic leukemias). The mean chromium release (effector-to-target cell ratio 50:1) was 28.8 +/- 13.5% for LAK-sensitive leukemias versus 5.2 +/- 3.2% for resistant leukemias. We observed a distinct susceptibility of various leukemia subtypes. LAK cytotoxicity against autologous leukemia cells was examined in 40 leukemia patients in complete remission (24 AML, 16 ALL). 63% of the patients developed a significant cytotoxicity against their autologous leukemia cells. Regarding mean Cr releases, the efficiency of allogeneic LAK activity of normal donors did not differ significantly from that of autologous LAK activity of patients in complete remission against the same leukemic target cells. Analysis of our data revealed that examinations with allogeneic LAK activity make it possible to predict whether patients will develop significant in vitro killing of their autologous leukemia cells during complete remission. These results may be of particular importance in determining which patients could benefit from immunologic therapy modalities and in scheduling immunotherapy. Further clinical studies are necessary to ascertain the clinical significance of therapeutic approaches with IL-2 or adoptive cellular immunotherapy combined with IL-2 for treatment of human leukemia.

Acute Disease↗

MR imaging of pregnancy in bicornuate uterus.

We report a case of incarcerated bicornuate pregnancy diagnosed by magnetic resonance. In this unusual case both CT and sonography suggested an abdominal pregnancy. Magnetic resonance may be a valuable adjunct to sonography in the management of the complicated pregnancy in spite of nonvisualization of the fetal parts due to fetal movement.

Adult↗

Expression of the stem cell factor receptor C-KIT (CD117) in acute leukemias.

BACKGROUND AND OBJECTIVE: The receptor for stem cell factor (CD117) is the gene product of the c-kit proto-ontogene. Together with its ligand, the stem cell factor (SCF), it plays an important role in hematopoiesis. In this study, we review the cellular distribution of CD117 in normal hematopoiesis and in hematopoietic malignancies focusing on the differential expression in subtypes of acute leukemias. EVIDENCE AND INFORMATION SOURCES: This review is based on a literature search in the Medline database, personal publications and results obtained as a reference laboratory of the German AML-BFM, AMLCG and ALL multi-center therapy studies. STATE OF THE ART AND PERSPECTIVES: Membrane expression of CD117 can be found on leukemic blasts from approximately 60% of adult and childhood AML patients, often associated with an immature immunophenotype (CD34). Moreover, AML with t(8;21) are frequently CD117 positive. Despite earlier reports, most recent studies have not been able to demonstrate any significant prognostic impact of CD117 expression in either childhood or adult AML. A small proportion of T-lineage ALL (9%), mainly consisting of immature pro-T/pre-T-ALL, is CD117 positive. CD117 expression is rare in B-cell-precursor-ALL and occurs in less than 3% of cases. CD117 in combination with other antigens might facilitate the immunologic characterization of acute leukemias, especially those of myeloid and early T-cell origin.

Acute Disease↗