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H H Wacker

Publications and source records attributed to H H Wacker.

At least 37 records · Page 2Linked to original sources
PubMed1996

Monoclonal antibodies Ki-S3 and Ki-S5 yield new data on the 'Ki-67' proteins.

The monoclonal antibody (mab) Ki-67 has been used for about 10 years, mainly in tissue sections, to monitor proliferating cells, but so far only very little is known about the proteins it recognizes. The new mabs Ki-S3 and Ki-S5 detect proliferating cells in frozen and paraffin-embedded tissues. They recognize proteins with the same molecular mass as Ki-67 in Western blot and for the first time also in immunoprecipitation experiments. With these mabs we were able to enrich and purify the Ki-67 proteins. Protein sequencing of four peptides of the digested proteins corresponded to the cDNA-deduced amino acid sequence already published for the Ki-67 proteins. Since we were able to immunoprecipitate the Ki-67 proteins, we performed various immunoprecipitation experiments to obtain more information about the nature of these proteins. After radiolabelling L428 cells with [35S]-methionine we were able to immunoprecipitate the Ki-67 proteins after only 5 min of labelling time. In turnover experiments the Ki-67 proteins could not be detected 3 h after the end of labelling. These data indicate a half-life of the Ki-67 proteins of about 90 min. Labelling experiments with [32P]-orthophosphate revealed that the Ki-67 proteins are phosphorylated. After dephosphorylation was blocked with okadaic acid or cell growth was arrested by means of Colcemid, the phosphorylation of the Ki-67 proteins was greatly increased, indicating that the Ki-67 proteins are phosphorylated via serine and threonine, and that the phosphorylation of the Ki-67 proteins increases in cycling cells. Labelling experiments with [3H]-mannose and [3H]-glucose revealed that the protein is weakly N-glycosylated.

Amino Acid Sequence↗
PubMed1996

Cutaneous monoblastic leukemia as a first sign of relapse six years after autologous bone marrow transplantation for acute leukemia.

A patient with acute monoblastic leukemia (AML, M5A) was treated successfully in December 1987. In 1993 after 6 years in complete remission, she presented with an intracutaneous nodular mass on her right upper arm which was resected in toto and shown to be undifferentiated monoblastic leukemia. Two further chloroma lesions were excised in July 1994 and March 1995 respectively. Bone marrow cytology and histology always showed a continuing complete remission with no evidence of leukemia relapse. In July 1995 she presented with a disseminated skin infiltrate and a relapse with 80% monoblasts in the bone marrow. After one course of chemotherapy (Idarubicin/Ara-C), a second complete remission was achieved and her leukemic skin infiltrate disappeared completely. This case illustrates that chloromas of the skin can occur as late as 6 years after treatment for AML and also emphasizes that the occurrence of a chloroma does not necessarily mean immediate leukemia relapse. It also stresses that a second complete remission can be achieved with standard AML-induction therapy despite widespread leukemic skin infiltrates in such patients.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

[Clonal B-cell reactions and prelymphoma in autoimmune diseases].

With the establishment of the MALT concept in immunology it became obvious that B cells play an important role in the autoimmune diseases of the MALT. We immunophenotyped the intraepithelial B cells occurring in Hashimoto's disease, Sjögren's syndrome and Helicobacter pylori-associated gastritis and looked for clonal T-cell receptor gamma chains (TCR-gamma) and immunoglobulin heavy chains (JH). Immunophenotypically, we identified predominantly monocytoid B cells as the effector cells in the salivary glands of patients with Sjögren's syndrome, whereas in the thyroid and stomach the effector cells were marginal zone cells. Polyclonal rearrangements were found in 11/25 patients with Sjögren's syndrome, 23/40 patients with Hashimoto's disease and 19/24 patients with gastritis. Accordingly, 14 of the patients with Sjögren's syndrome, 17 of the patients with Hashimoto's disease and 5 of the patients with gastritis showed monoclonal rearrangements. Immunohistochemically, all patients with clonal rearrangements were found to have lymphoepithelial lesions. In these patients a transition to a low grade MALT lymphoma could be diagnosed. From these results we can conclude that in these two autoimmune diseases clonal rearrangements must be considered at least potentially malignant and that intraepithelial B cells should probably be considered the promoters of autoimmune diseases and of the development of primary extranodal B-cell lymphomas.

Autoimmune Diseases↗
PubMed1995

Temperature gradient gel electrophoresis for analysis of clonal evolution in non-Hodgkin's lymphoma of the thyroid.

To analyze the transition of an autoimmune disease into a mucosa-associated lymphoid tissue-non-Hodgkin's lymphoma (MALT-NHL), we investigated a total of 27 cases of clinically diagnosed autoimmune thyroiditis with lymphoid hyperplasia. Three cases of thyroid hyperplasia served as controls. Monoclonal B cells were detected by studying rearrangement patterns of the hypervariable CDR III regions within the immunoglobulin heavy chain gene locus and the T-cell receptor gamma chain gene (TCRG). We used a seminested polymerase chain reaction (PCR) to demonstrate immunoglobulin rearrangements and a multiplex PCR for TCRG rearrangements. The PCR products were analyzed by temperature gradient gel electrophoresis to expand mixtures of homo- and hetero-duplices within heterogeneous populations of B cells. With this approach we found monoclonality in 14 of the 27 cases of Hashimoto's disease. In a reinvestigation we discovered additional histological and immunohistochemical features of MALT-NHL in 17 cases. The 14 cases of thyroiditis with clonally expanded B cells clearly demonstrate the transition from autoimmune disease to non-Hodgkin's lymphoma.

B-Lymphocytes↗
PubMed1995

[Castleman's disease: evaluation of 338 cases].

PURPOSE: To evaluate a large group of patients with Castleman's tumours (Castleman's disease = MC) with regard to age, sex and tumour localisation. PATIENTS AND METHODS: 338 cases of MC were evaluated. All cases were registered by the Lymphknotenregister of the German Society of Pathology, Kiel. RESULTS: 292 MC of the hyaline vascular type (MC-HV) and 46 of the plasma cell type (MC-PC) were found, 259 (76.6%) in nodal and 79 (23.4%) in extranodal localisation. Main nodal localisation were the neck (25.5%) and the axilla (12.8%). The mediastinum was involved in only 6.2%. There was a slight preference of female (56%) compared to male (44%). Patients with MC-PC (mean age: 50 +/- 16.9 years) were significantly older (p < 0.001) than patients with MC-HV (mean age: 39 +/- 18.9 years). CONCLUSIONS: The main localisation of MC is the neck. MC-HV is more common than MC-PC. There is a slight preference for women. Mean age of patients with MC-PC is approximate 10 years higher than for MC-HV.

Adolescent↗
PubMed1995

CD26 expression in leprosy and other granulomatous diseases correlates with the production of interferon-gamma.

BACKGROUND: Leprosy represents a spectrum of clinical manifestations that reflect the immune response to antigens of Mycobacterium leprae. The tuberculoid form of leprosy, which is characterized by an organized development of granulomas, has recently been correlated with a Th1-like immune response. The lepromatous form of leprosy, with a characteristic lack of cellular immunity, has been correlated with a Th2-like immune response to mycobacterial antigens. Dipeptidylpeptidase IV (CD26) is an ectopeptidase that is expressed in various tissues; in the hemopoietic system, it is predominantly expressed by T cells. EXPERIMENTAL DESIGN: We stained frozen sections of skin biopsies obtained from patients with different forms of leprosy, sarcoidosis, and Piringer's lymphadenitis. Sections were stained for interferon-gamma (IFN-gamma) and CD26 with the alkaline phosphatase anti-alkaline phosphatase technique and in two-color stainings by immunofluorescence. RESULTS: We found strong signals for IFN-gamma and for CD26 in all investigated cases of tuberculoid leprosy. In contrast, in all biopsies taken from patients with lepromatous leprosy, we found no or very weak signals for these antigens. By immunofluorescence double-labeling, we could show that IFN-gamma and CD26 were expressed by the identical cell population. We confirmed this correlation of CD26 expression and IFN-gamma production in other granulomatous inflammatory reactions such as sarcoidosis and Piringer's lymphadenitis. CONCLUSIONS: From our results, we conclude that a high expression of CD26 may be suggestive of Th1-like immune reactions.

Dipeptidyl Peptidase 4↗
PubMed1994

Antidisialoganglioside ricin A-chain immunotoxins show potent antitumor effects in vitro and in a disseminated human neuroblastoma severe combined immunodeficiency mouse model.

Several monoclonal antibodies (mAbs) were screened on different neuroblastoma cell lines to evaluate ricin A-chain immunotoxins for possible use against human neuroblastoma. Four mAbs were identified that exhibited high antitumor activity against neuroblastoma cell lines as measured in an indirect cytotoxicity assay. These mAbs, including 14G2a (antidisialoganglioside), ch14.18 (a humanized switch variant), BW704 (antidisialoganglioside), and chCE7 (anti-glycoprotein of M(r) 190,000), were subsequently linked via the bivalent linker N-succinimidyloxycarbonyl-alpha-methyl-alpha-(2-piridyldithio++ +)toluene to deglycosylated ricin A chain. The most potent immunotoxin, 14G2a.dgA, inhibited the protein synthesis of neuroblastoma cell lines IMR5 and NMB by 50% at concentrations of 6 x 10(-12) M. To test the antitumor efficacy of these immunotoxins in vivo, we developed a disseminated human neuroblastoma model in severe combined immunodeficiency mice. Treatment of tumor-bearing mice with 14G2a.dgA 12 days after tumor challenge resulted in a significant prolongation of survival as compared with phosphate-buffered saline-treated controls (16.8 versus 6.5 weeks). We conclude that ricin A-chain immunotoxins might be of potential use in the treatment of human neuroblastoma.

Animals↗
PubMed1994

DNA content and the proliferation marker Ki-67 as prognostic indicators in renal cell carcinoma.

Patients suffering from renal cell carcinoma have a generally poor prognosis. Even cases that are clinically in comparable stages can, however, take quite different courses. The basic prognostic factors, histological grade and TNM stage do not do justice to the heterogeneous biological behavior of this tumor entity. In this study, the possible prognostic indicators, DNA content and proliferation rate, assessed with Ki-67, were compared with the histological grade and the TNM stage. Though there was no correlation between the proliferation rate (Ki-67) and the two, there was a significant correlation between DNA content and both histological grade and TNM stage.

Aneuploidy↗
PubMed1994

Follicular dendritic cells in non-Hodgkin's lymphomas.

Follicular dendritic cells (FDC) are restricted to the B-cell regions of secondary lymphoid tissue and to non-Hodgkin's lymphomas derived from the follicular center or the mantle zone. With their cytoplasmic ramifications they form a dense network which contains the B-lymphocytes. In situ, FDC are only detectable at the ultrastructural level or when stained with anti FDC-reagents. On the surface of their dendritic extensions they express transferrin receptors (CD71), the B-cell epitope CD20, class II antigens, the myelomonocytic molecule CD14, the glycoprotein gp50 (CD40), and several receptors for components of the complement system (CD11b, CD21, CD35). Subsequent to an antigen challenge, FDC trap and retain immune-complexes for a long period of time. In vitro FDC and neoplastic lymphocytes spontaneously form small cellular aggregates. This adhesion is mediated by the LFA-1-alpha/beta = ICAM-1, the VLA-4 = VCAM-1, and the ICAM-1 = C3bi- receptor ligand pathways on B-cells and on FDC, respectively. The loss of LFA-1- alpha/beta and ICAM-1 molecules may enable neoplastic lymphocytes to detach from FDC. The monoclonal B-cells now invade new compartments. In vitro, FDC have the capacity to activate resting B-cells and to save them from dying by apoptosis. Signals involved in this activation include cell-surface immunoglobulin and CD40. Immunocytochemistry and autoradiography with single cell suspensions of neoplastic B cells suggest that FDC also provide signals leading to the continued stimulation of lymphoma lymphocytes. During the early stage of HIV infection lymph nodes show an immense follicular hyperplasia, with a massive increase of the dendritic network of FDC. In the later stage of the disease, the continuous involution of the germinal centers is associated with a progressive destruction of FDC.

Antigen Presentation↗
PubMed1994

[Intensification of sensitivity of monoclonality determination of B-cells in autoimmune thyroiditis and low malignancy B-NHL of the MALT type using temperature gradient gel electrophoresis (TGGE)].

Malignant non-Hodgkins lymphoma with primary involvement of the thyroid is a rare disease. Nearly all these lymphomas are of B-cell phenotype, and they represent a broad morphological spectrum of high and low grade entities. We investigated 18 cases of Hashimotos disease and 95 cases of thyroid non-Hodgkins lymphoma including 16 cases of MALT-lymphoma. This type of lymphoma is often hardly distinguishable from reactive lesions, even by immunohistochemistry. Therefore, we introduced a new molecular genetic technique based on the polymerase chain reaction (PCR) combined with temperature-gradient gel electrophoresis to demonstrate monoclonal populations of B cells in a polyclonal background of reactive B lymphocytes. With this approach we found monoclonality in 4 of 18 cases of Hashimotos disease. In our opinion, these 4 cases demonstrate clearly the transition from autoimmune disease into non-Hodgkins lymphoma.

B-Lymphocytes↗
PubMed1994

Altered expression of the retinoblastoma gene product in human high grade non-Hodgkin's lymphomas.

The retinoblastoma gene (RB) is a growth suppressor gene on the human chromosome 13q14. It encodes a 105 kDa phosphoprotein (p105), with DNA-binding capacity. P105 is thought to be involved in cell cycle control. Inactivation of RB is responsible for the development of retinoblastomas and occurs frequently in osteosarcomas and small cell lung cancer. In this study we looked at the RB-structure and expression in cell lines and primary lymphoma samples from patients with high grade non-Hodgkin's lymphoma (NHL). Forty five primary high grade NHL, the B-lymphoblastoid cell line IM-9 and the NHL cell line WSU-NHL were studied for RB structure by Southern blotting and for RB-expression by Northern blotting, Western blotting and immunocytochemistry. In all experiments freshly cryopreserved material was used. Southern and Northern experiments were performed with the 0.9 kb and 3.8 kb RB-cDNA probe. For the detection of p105 two different anti-p105-monoclonal antibodies were used in immunocytochemistry and Western blotting experiments. No RB mRNA and no p105 could be found in IM-9 cells. Twenty six high grade NHL samples (58%) showed no p105 expression. In the subgroup of centroblastic lymphomas 16 out of 21 and in Burkitt's lymphomas five out of eight showed no p105-expression. P105 expression is absent in 58% of high grade NHL, particularly in centroblastic and Burkitt's lymphomas, suggesting that inactivation of RB may play a crucial role in the pathogenesis of high grade NHL.

Blotting, Northern↗
PubMed1993

Determination of the growth fraction in non-Hodgkin's lymphomas by monoclonal antibody Ki-S5 directed against a formalin-resistant epitope of the Ki-67 antigen.

Relevant prognostic information can be added to the histological classification of non-Hodgkin's lymphoma (NHL) by the determination of the growth fraction. In unfixed fresh tissue samples the Ki-67 antigen has proven its utility as an operational marker of proliferative activity in NHL. We have generated a monoclonal antibody directed against a formalin-resistant epitope of the Ki-67 antigen, designated Ki-S5. The immunoreactivity of Ki-S5 is confined to the nuclei of proliferating cells and, unlike Ki-67, no cross-reactivity with cytoplasmic antigens of epithelial cells occurs. In 100 cases of different NHL types, parallel staining of Ki-67 and Ki-S5 antigen yielded almost identical results in fresh tissues and fixed tissues, respectively (P < 0.00001; r = 0.95). In some cases, the Ki-S5 labeling index exceeded that of Ki-67, most probably due to a partial degradation of the epitope recognized by Ki-67 in frozen stored tissue samples. Significant differences in the median Ki-S5 labeling index could be demonstrated between high grade (> 50%) and low grade malignant NHL (< or = 30%), although the proliferative activity varied to a considerable range within identical histological categories (P < 0.001). We conclude that Ki-S5 provides a reliable means to assess proliferation in paraffin-embedded NHL specimens. Retrospective studies relating the proliferative activity to clinical outcome are thus rendered possible using archival routinely processed tissue samples.

Aged↗