1
|
Vill K, Sehri M, Müller C, Hannibal I, Huf V, Idriess M, Gerstl L, Bonfert MV, Tacke M, Schroeder AS, Landgraf MN, Müller-Felber W, Blaschek A. Qualitative and quantitative muscle ultrasound in patients with Duchenne muscular dystrophy: Where do sonographic changes begin? Eur J Paediatr Neurol 2020; 28:142-150. [PMID: 32758414 DOI: 10.1016/j.ejpn.2020.06.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 05/19/2020] [Accepted: 06/04/2020] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The number of studies investigating and understanding the disease mechanisms of Duchenne muscular dystrophy (DMD) in human clinical trials have increased substantially over the last decade. Suitable clinical instruments for the measurement of disease progress and drug efficiency are mandatory, but currently not available, especially in the youngest patients. The aim of this study was to detect a reproducible pattern of muscle involvement in early stages potentially preceding evidence of motor regression. MATERIAL AND METHODS A cohort of 25 DMD patients aged 1-6 years at the first presentation were examined at multiple timepoints and compared with age-matched healthy controls. Muscle ultrasound was quantified using computer-analyzed gray scale levels (GSL) and blinded visual rating, using a modified Heckmatt scale. RESULTS Changes in muscle echogenicity in DMD patients occurred very early, clearly preceding motor regression and in some cases, even before the motor plateau phase was reached. Visual rating and GSL identified the earliest changes in the proximal adductor magnus muscle. CONCLUSION Muscle ultrasound can be used as an additional method to assess the disease progression and for decision-making in paucisymptomatic DMD patients. Sonographic changes in the ad-ductor magnus muscle seem to be the first detectable changes with a recognisable pattern.
Collapse
Affiliation(s)
- K Vill
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany.
| | - M Sehri
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - C Müller
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - I Hannibal
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - V Huf
- Department of Radiology, University Medical Center Regensburg, Germany.
| | - M Idriess
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - L Gerstl
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - M V Bonfert
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - M Tacke
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - A S Schroeder
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - M N Landgraf
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - W Müller-Felber
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| | - A Blaschek
- LMU Munich, University Hospital, Dr. von Hauner Children's Hospital, Department of Pediatrics, Disvision of Pediatric Neurology and Developmental Medicine, Munich, Germany
| |
Collapse
|
2
|
Vill K, Blaschek A, Gläser D, Kuhn M, Haack T, Alhaddad B, Wagner M, Kovacs-Nagy R, Tacke M, Gerstl L, Schroeder AS, Borggraefe I, Mueller C, Schlotter-Weigel B, Schoser B, Walter MC, Müller-Felber W. Early-Onset Myopathies: Clinical Findings, Prevalence of Subgroups and Diagnostic Approach in a Single Neuromuscular Referral Center in Germany. J Neuromuscul Dis 2019; 4:315-325. [PMID: 29172004 DOI: 10.3233/jnd-170231] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Early-onset myopathies are a heterogeneous group of neuromuscular diseases with broad clinical, genetic and histopathological overlap. The diagnostic approach has considerably changed since high throughput genetic methods (next generation sequencing, NGS) became available. OBJECTIVE We present diagnostic subgroups in a single neuromuscular referral center and describe an algorithm for the diagnostic work-up. METHODS The diagnostic approach of 98 index patients was retrospectively analysed. In 56 cases targeted sequencing of a known gene was performed, in 44 patients NGS was performed using large muscle specific panels, and in 12 individuals whole exome sequencing (WES) was undertaken. One patient was diagnosed via array CGH. Clinical features of all patients are provided. RESULTS The final diagnosis could be found in 63 out of 98 patients (64%) with molecular genetic analysis. In 55% targeted gene sequencing could establish the genetic diagnosis. However, this rate largely depended on the presence of distinct histological or clinical features. NGS (large myopathy-related panels and WES) revealed genetic diagnosis in 58.5% (52% and 67%, respectively). The genes detected by WES in our cohort of patients were all covered by the panels. Based on our findings we propose an algorithm for a practical diagnostic approach.Prevalences:MTM1- and LAMA2-patients are the two biggest subgroups, followed by SEPN1-, RYR1- and Collagen VI-related diseases. 31% of genetically confirmed cases represents a group with overlap between "congenital myopathies (CM)" and "congenital muscular dystrophies (CMD)". In 36% of the patients a specific genetic diagnosis could not be assigned. CONCLUSIONS A final diagnosis can be confirmed by high throughput genetic analysis in 58.5% of the cases, which is a higher rate than reported in the literature for muscle biopsy and should in many cases be considered as a first diagnostic tool. NGS cannot replace neuromuscular expertise and a close discussion with the geneticists on NGS is mandatory. Targeted candidate gene sequencing still plays a role in selected cases with highly suspicious clinical or histological features. There is a relevant clinical and genetic overlap between the entities CM and CMD.
Collapse
Affiliation(s)
- K Vill
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Center for Neuromuscular Disorders in Childhood. Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Germany
| | - A Blaschek
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Center for Neuromuscular Disorders in Childhood. Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Germany
| | - D Gläser
- genetikum® Center for Human Genetics, Neu-Ulm, Germany
| | - M Kuhn
- genetikum® Center for Human Genetics, Neu-Ulm, Germany
| | - T Haack
- Institute of Human Genetics, Technische Universität München, Munich, Germany.,Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany.,Institute of Human Genetics, University of Tübingen, Germany
| | - B Alhaddad
- Institute of Human Genetics, Technische Universität München, Munich, Germany.,Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - M Wagner
- Institute of Human Genetics, Technische Universität München, Munich, Germany.,Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany.,Institute für Neurogenomik, Helmholtz Zentrum München, Neuherberg, Germany
| | - R Kovacs-Nagy
- Institute of Human Genetics, Technische Universität München, Munich, Germany
| | - M Tacke
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Center for Neuromuscular Disorders in Childhood. Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Germany
| | - L Gerstl
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Center for Neuromuscular Disorders in Childhood. Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Germany
| | - A S Schroeder
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Center for Neuromuscular Disorders in Childhood. Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Germany
| | - I Borggraefe
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Center for Neuromuscular Disorders in Childhood. Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Germany
| | - C Mueller
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Center for Neuromuscular Disorders in Childhood. Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Germany
| | - B Schlotter-Weigel
- Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-Universität, München, Munich, Germany
| | - B Schoser
- Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-Universität, München, Munich, Germany
| | - M C Walter
- Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-Universität, München, Munich, Germany
| | - W Müller-Felber
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Center for Neuromuscular Disorders in Childhood. Dr. von Hauner Children's Hospital, University Hospital, LMU Munich, Germany
| |
Collapse
|
3
|
Tacke M, Neubauer BA, Gerstl L, Roser T, Rémi J, Borggraefe I. [Epilepsy-new diagnostic tools, old drugs? : Therapeutic consequences of epilepsy genetics]. Nervenarzt 2017; 88:1385-1394. [PMID: 28932874 DOI: 10.1007/s00115-017-0427-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Recent advances in the field of epilepsy genetics have led to an increased fraction of patients with epilepsies where the etiology of the disease could be identified. Nevertheless, there is some criticism regarding the use of epilepsy genetics because in many cases the identification of a pathogenetic mutation does not lead to an adaptation of therapy or to an improved prognosis. In addition, the interpretation of genetic results might be complicated due to the considerable numbers of variants of unclear significance. OBJECTIVE This publication presents the arguments in favour of a broad use of genetic investigations for children with epilepsies. Several diseases where a genetic diagnosis does in fact have direct therapeutic consequences are mentioned. In addition, the indirect impact of an established etiology, encompassing the avoidance of unnecessary diagnostic measures, possibility of genetic counselling, and the easing of the psychologic burden for the caregivers, should not be underestimated. CONCLUSION The arguments in favour of broad genetic diagnostics prevail notwithstanding the lack of relevant new developments regarding the therapy.
Collapse
Affiliation(s)
- M Tacke
- Abteilung für Pädiatrische Neurologie und Entwicklungsneurologie, LMU Zentrum - iSPZ Hauner, Sektion für Pädiatrische Epileptologie, Kinderklinik und Kinderpoliklinik im Dr. von Haunerschen Kinderspital, Universität München, Lindwurmstr. 4, 80337, München, Deutschland
| | - B A Neubauer
- Abteilung für Neuropädiatrie, Sozialpädiatrie und Epileptologie, Universitätskinderklinik, Universität Gießen-Marburg, Gießen, Deutschland
| | - L Gerstl
- Abteilung für Pädiatrische Neurologie und Entwicklungsneurologie, LMU Zentrum - iSPZ Hauner, Sektion für Pädiatrische Epileptologie, Kinderklinik und Kinderpoliklinik im Dr. von Haunerschen Kinderspital, Universität München, Lindwurmstr. 4, 80337, München, Deutschland
| | - T Roser
- Abteilung für Pädiatrische Neurologie und Entwicklungsneurologie, LMU Zentrum - iSPZ Hauner, Sektion für Pädiatrische Epileptologie, Kinderklinik und Kinderpoliklinik im Dr. von Haunerschen Kinderspital, Universität München, Lindwurmstr. 4, 80337, München, Deutschland
| | - J Rémi
- Neurologische Klinik und Poliklinik & Deutsches Schwindel- und Gleichgewichtszentrum (DSGZ), Campus Großhadern, Klinikum der Universität München, München, Deutschland.,Interdisziplinäres Epilepsiezentrum am Campus Großhadern und im Dr. von Haunerschen Kinderspital, Klinikum der Universität München, München, Deutschland
| | - I Borggraefe
- Abteilung für Pädiatrische Neurologie und Entwicklungsneurologie, LMU Zentrum - iSPZ Hauner, Sektion für Pädiatrische Epileptologie, Kinderklinik und Kinderpoliklinik im Dr. von Haunerschen Kinderspital, Universität München, Lindwurmstr. 4, 80337, München, Deutschland. .,Interdisziplinäres Epilepsiezentrum am Campus Großhadern und im Dr. von Haunerschen Kinderspital, Klinikum der Universität München, München, Deutschland.
| |
Collapse
|
4
|
Abstract
Benzyl-substituted metallocarbene compounds synthesised by our group and others during the past 5 years give a new perspective on their activity as antibiotic and antitumoral drugs. N-heterocyclic carbenes containing an imidazole core were functionalised and their transition metal complexes (M = Ag, Au, Cu, Ru) have shown promising antibacterial as well as anticancer activity in vitro and in vivo. IC50 values in the nanomolar region or antibacterial activity comparable to conventional antibiotics lead the way towards novel drug candidates.
Collapse
Affiliation(s)
- F Hackenberg
- University College Dublin, Belfield, Dublin 4, Ireland.
| | | |
Collapse
|
5
|
Fulster S, Tacke M, Sandek A, Ebner N, Tschope C, Doehner W, Anker SD, von Haehling S. Muscle wasting in patients with chronic heart failure: results from the studies investigating co-morbidities aggravating heart failure (SICA-HF). Eur Heart J 2012. [DOI: 10.1093/eurheartj/ehs381] [Citation(s) in RCA: 381] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
|
6
|
Kater L, Claffey J, Hogan M, Jesse P, Kater B, Strauß S, Tacke M, Prokop A. The role of the intrinsic FAS pathway in Titanocene Y apoptosis: The mechanism of overcoming multiple drug resistance in malignant leukemia cells. Toxicol In Vitro 2012; 26:119-24. [DOI: 10.1016/j.tiv.2011.09.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Revised: 09/12/2011] [Accepted: 09/14/2011] [Indexed: 12/22/2022]
|
7
|
Dennemärker J, Lohmüller T, Mayerle J, Tacke M, Lerch MM, Coussens LM, Peters C, Reinheckel T. Deficiency for the cysteine protease cathepsin L promotes tumor progression in mouse epidermis. Oncogene 2009; 29:1611-21. [PMID: 20023699 DOI: 10.1038/onc.2009.466] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
To define a functional role for the endosomal/lysosomal cysteine protease cathepsin L (Ctsl) during squamous carcinogenesis, we generated mice harboring a constitutive Ctsl deficiency in addition to epithelial expression of the human papillomavirus type 16 oncogenes (human cytokeratin 14 (K14)-HPV16). We found enhanced tumor progression and metastasis in the absence of Ctsl. As tumor progression in K14-HPV16 mice is dependent on inflammation and angiogenesis, we examined immune cell infiltration and vascularization without finding any effect of the Ctsl genotype. In contrast, keratinocyte-specific transgenic expression of cathepsin V, the human orthologue of mouse Ctsl, in otherwise Ctsl-deficient K14-HPV16 mice restored the phenotype observed in the control HPV16 skin. To better understand this phenotype at the molecular level, we measured several oncogenic signal transduction pathways in primary keratinocytes on stimulation with keratinocyte-conditioned cell culture medium. We found increased activation of protein kinase B/Akt and mitogen-activated protein kinase pathways in protease-deficient cells, especially if treated with media conditioned by Ctsl-deficient keratinocytes. Similarly, the level of active GTP-Ras was increased in Ctsl-deficient epidermis. We conclude that Ctsl is critical for the termination of growth factor signaling in the endosomal/lysosomal compartment of keratinocytes and, therefore, functions as an anti-tumor protease.
Collapse
Affiliation(s)
- J Dennemärker
- Institute for Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Krauss A, Rau A, Tacke M, Nill S, Oelfke U. Real-time Tumor Position Monitoring and Dynamic Dose Adaptation: Geometric and Dosimetric Accuracy of an Integrated Tracking System. Int J Radiat Oncol Biol Phys 2009. [DOI: 10.1016/j.ijrobp.2009.07.187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
9
|
Oelfke U, Tacke M, Kraus A, Nill S. Sci-Wed PM: Delivery-06: Management of Intra-Fraction Organ Motion: First Performance Evaluation of an Experimental Dynamic Tumor Tracking System. Med Phys 2009. [DOI: 10.1118/1.3244098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
10
|
Genova-Kalou P, Barkina T, Ignatova D, Toshev A, Tacke M. Inhibition of Herpes Simplex Virus Type 1 Infection by Some Selected Antitumor Titanium(III)-Based Coordination Compounds. BIOTECHNOL BIOTEC EQ 2009. [DOI: 10.1080/13102818.2009.10818474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
|
11
|
Dowling C, Cuffe S, Tacke M, Fitzpatrick J, Watson W. 493 POSTER Manipulating prostate cancer cell susceptibility to docetaxel and novel titanocene analogues induced apoptosis. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)72427-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
12
|
Cuffe S, Dowling C, Gill C, Tacke M, Fitzpatrick J, Carty M, Watson R. Novel titanocene analogues induce apoptosis in prostate cancer epithelial cells by initiating a DNA damage response. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)71286-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
|
13
|
Tacke M, Nill S, Oelfke U. SU-EE-A1-05: A Real-Time Feedback Control Algorithm to Compensate 2D Target Motion with a Dynamic Multileaf Collimator. Med Phys 2008. [DOI: 10.1118/1.2961378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
14
|
Tacke M, Hogan M, Claffey J, Pampillon C. Synthesis and Cytotoxicity Studies of New Morpholino-Functionalised and N-Heteroaryl-Substituted Titanocene Anticancer Drugs. Med Chem 2008; 4:91-9. [DOI: 10.2174/157340608783789202] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
15
|
Bühler P, Wolf P, Gierschner D, Schaber I, Katzenwadel A, Schultze-Seemann W, Wetterauer U, Tacke M, Swamy M, Schamel WWA, Elsässer-Beile U. A bispecific diabody directed against prostate-specific membrane antigen and CD3 induces T-cell mediated lysis of prostate cancer cells. Cancer Immunol Immunother 2007; 57:43-52. [PMID: 17579857 PMCID: PMC2755730 DOI: 10.1007/s00262-007-0348-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Accepted: 05/23/2007] [Indexed: 12/03/2022]
Abstract
Background Although cancer of the prostate is one of the most commonly diagnosed cancers in men, no curative treatment currently exists after its progression beyond resectable boundaries. Therefore, new agents for targeted treatment strategies are needed. Cross-linking of tumor antigens with T-cell associated antigens by bispecific monoclonal antibodies have been shown to increase antigen-specific cytotoxicity in T-cells. Since the prostate-specific membrane antigen (PSMA) represents an excellent tumor target, immunotherapy with bispecific diabodies could be a promising novel treatment option for prostate cancer. Methods A heterodimeric diabody specific for human PSMA and the T-cell antigen CD3 was constructed from the DNA of anti-CD3 and anti-PSMA single chain Fv fragments (scFv). It was expressed in E. coli using a vector containing a bicistronic operon for co-secretion of the hybrid scFv VHCD3-VLPSMA and VHPSMA-VLCD3. The resulting PSMAxCD3 diabody was purified from the periplasmic extract by immobilized metal affinity chromatography (IMAC). The binding properties were tested on PSMA-expressing prostate cancer cells and PSMA-negative cell lines as well as on Jurkat cells by flow cytometry. For in vitro functional analysis, a cell viability test (WST) was used. For in vivo evaluation the diabody was applied together with human peripheral blood lymphocytes (PBL) in a C4-2 xenograft-SCID mouse model. Results By Blue Native gel electrophoresis, it could be shown that the PSMAxCD3 diabody is mainly a tetramer. Specific binding both to CD3-expressing Jurkat cells and PSMA-expressing C4-2 cells was shown by flow cytometry. In vitro, the diabody proved to be a potent agent for retargeting PBL to lyze C4-2 prostate cancer cells. Treatment of SCID mice inoculated with C4-2 tumor xenografts with the diabody and PBL efficiently inhibited tumor growth. Conclusions The PSMAxCD3 diabody bears the potential for facilitating immunotherapy of prostate cancer and for the elimination of minimal residual disease.
Collapse
Affiliation(s)
- P. Bühler
- Department of Urology, Experimental Urology, University of Freiburg, Breisacher Str. 117, 79106 Freiburg, Germany
- Faculty of Biology, University of Freiburg, Schänzle Str. 1, 79104 Freiburg, Germany
| | - P. Wolf
- Department of Urology, Experimental Urology, University of Freiburg, Breisacher Str. 117, 79106 Freiburg, Germany
| | - D. Gierschner
- Department of Urology, Experimental Urology, University of Freiburg, Breisacher Str. 117, 79106 Freiburg, Germany
| | - I. Schaber
- Department of Urology, Experimental Urology, University of Freiburg, Breisacher Str. 117, 79106 Freiburg, Germany
| | - A. Katzenwadel
- Department of Urology, Experimental Urology, University of Freiburg, Breisacher Str. 117, 79106 Freiburg, Germany
| | - W. Schultze-Seemann
- Department of Urology, Experimental Urology, University of Freiburg, Breisacher Str. 117, 79106 Freiburg, Germany
| | - U. Wetterauer
- Department of Urology, Experimental Urology, University of Freiburg, Breisacher Str. 117, 79106 Freiburg, Germany
| | - M. Tacke
- Institute of Molecular Medicine and Cell Research, University of Freiburg, Stefan-Meier-Strasse 17, 79106 Freiburg, Germany
| | - M. Swamy
- Department of Molecular Immunology, Max-Planck-Institute for Immunobiology and University of Freiburg, Biologie III, Stübeweg 51, 79108 Freiburg, Germany
| | - W. W. A. Schamel
- Department of Molecular Immunology, Max-Planck-Institute for Immunobiology and University of Freiburg, Biologie III, Stübeweg 51, 79108 Freiburg, Germany
| | - U. Elsässer-Beile
- Department of Urology, Experimental Urology, University of Freiburg, Breisacher Str. 117, 79106 Freiburg, Germany
| |
Collapse
|
16
|
O'Connor K, Gill C, Tacke M, Rehmann FJK, Strohfeldt K, Sweeney N, Fitzpatrick JM, Watson RWG. Novel titanocene anti-cancer drugs and their effect on apoptosis and the apoptotic pathway in prostate cancer cells. Apoptosis 2006; 11:1205-14. [PMID: 16699961 DOI: 10.1007/s10495-006-6796-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Advanced prostate cancer is not curable by current treatment strategies indicating a significant need for new chemotherapeutic options. Highly substituted ansa-titanocene compounds have shown promising cytotoxic activity in a range of cancers. The objectives of this study are to examine the effects of these titanocene compounds on prostate cancer cells. Prostate cell lines were treated with three novel titanocene compounds and compared to titanocene dichloride and cisplatin. Percent apoptosis, viability and cell cycle were assessed using propidium iodide DNA incorporation with flow cytometry. Cytochrome C was assessed by western blotting of mitochondrial and cytoplasmic fractions. Apoptosis Inducing Factor was assessed by confocal microscopy. These novel compounds induced more apoptosis compared to cisplatin in a dose dependent manner. Compound Y had the most significant effect on cell cycle and apoptosis. Despite the release of cytochrome C from the mitochondrial fraction there was no inhibition of apoptosis with the pan caspase inhibitor, ZVAD-FMK. AIF was shown to translocate from the cytosol to the nucleus mediating a caspase independent cell death. Bcl-2 over expressing PC-3 cells, which were resistant to cisplatin induced apoptosis, underwent apoptosis following treatment with all the titanocene compounds. This study demonstrates possible mechanisms by which these novel titanocene compounds can mediate their apoptotic effect in vitro. The fact that they can induce more apoptosis than cisplatin in advanced cancer cell lines would confer an advantage over cisplatin. They represent exciting new agents with future potential for the treatment of advanced prostate cancer.
Collapse
Affiliation(s)
- K O'Connor
- UCD School of Medicine and Medical Sciences, Mater Misericordiae University Hospital, University College Dublin, Belfield, Dublin 4, Ireland
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Salouero J, Sánchez-Doblado F, Leal A, Linares R, Arráns R, Leidenberger S, Schulze C, Szegedi M, Tacke M. 328 Leakage evaluation as a function of the tip angle for a non tongue and groove multileaf collimator using Monte Carlo simulation. Radiother Oncol 2005. [DOI: 10.1016/s0167-8140(05)81304-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
18
|
Tacke M, Szymanowski H, Schulze C, Nuss S, Wehrwein E, Leidenberger S, Oelfke U. SU-FF-T-294: Monte Carlo Simulations of the Dosimetric Characteristics of a New Multileaf Collimator. Med Phys 2005. [DOI: 10.1118/1.1998023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
19
|
|
20
|
Vogt F, Tacke M, Jakusch M, Mizaikoff B. Erratum to “A UV spectroscopic method for monitoring aromatic hydrocarbons dissolved in water” [Analytica Chimica Acta 422 (2000) 187–198]. Anal Chim Acta 2001. [DOI: 10.1016/s0003-2670(00)01260-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
21
|
Tacke M, Fox S, Cuffe L, Dunne J, Hartl F, Mahabiersing T. A study of the reduction of substituted fulvenes using spectro-electrochemistry and ab initio theory. J Mol Struct 2001. [DOI: 10.1016/s0022-2860(00)00710-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
22
|
|
23
|
Heuft HG, Berg T, Schreier E, Künkel U, Tacke M, Schwella N, Hopf U, Salama A, Huhn D. Epidemiological and clinical aspects of hepatitis G virus infection in blood donors and immunocompromised recipients of HGV-contaminated blood. Vox Sang 2000; 74:161-7. [PMID: 9595643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND OBJECTIVES The infectiousness and clinical relevance of the newly discovered blood-borne Flaviviridae-like agent, termed hepatitis G virus (HGV), are not well understood. MATERIALS AND METHODS Twenty-three transfusion recipients of two HGV-affected long-term blood donors were studied for HGV genome and antibodies to the putative envelope 2 glycoprotein (anti-E2) of HGV. Nine recipients had nonhematological disorders and 14 suffered from severe hematological diseases and 7 of them received allogeneic bone marrow or blood stem cell transplantation. The molecular epidemiology of the observed HGV infection was studied by direct sequencing of parts of the 5'-noncoding region, NS3, and NS5 region of HGV in the 2 long-term donors and in their 6 recipients who became HGV RNA positive. Additionally, 549 individuals-homologous (n = 254) and autologous blood donors (n = 202), and medical staff (n = 89)--were investigated for the presence of HGV RNA. RESULTS HGV RNA in serum was found in 15 of the 23 (65%) transfusion recipients with known exposure of HGV-contaminated blood. Seven of the remaining 8 recipients showed only an anti-E2 response, indicating previous HGV infection with spontaneous clearance of the virus. In one recipient neither HGV RNA nor anti-E2 could be detected. Molecular evidence for HGV transmission by the 2 donors was found in 3 of the 6 recipients studied. The alanine aminotransferase levels were not significantly different in the HGV RNA positive and negative recipients, and none of the 23 recipients developed posttransfusion hepatitis. Persistent HGV infection was observed especially in recipients with severe hematological disorders or in those in whom intensive immunosuppressive treatment was necessary. Of the 549 individuals studied, 10 (1.8%) were healthy carriers of HGV RNA. CONCLUSION The persistence of transfusion-acquired HGV infection is not associated with acute or chronic hepatitis, but may be influenced by the recipient's underlying disease.
Collapse
MESH Headings
- Adult
- Alanine Transaminase/blood
- Base Sequence
- Blood Donors
- Blood Transfusion, Autologous
- Female
- Flaviviridae/genetics
- Flaviviridae/isolation & purification
- Germany/epidemiology
- Health Personnel
- Hematologic Neoplasms/blood
- Hematologic Neoplasms/complications
- Hepatitis Antibodies/blood
- Hepatitis, Viral, Human/blood
- Hepatitis, Viral, Human/epidemiology
- Hepatitis, Viral, Human/prevention & control
- Hepatitis, Viral, Human/transmission
- Humans
- Immunocompromised Host
- Male
- Middle Aged
- Molecular Sequence Data
- Prevalence
- RNA, Viral/blood
- Sequence Alignment
- Sequence Homology, Nucleic Acid
- Transfusion Reaction
- Viral Envelope Proteins/immunology
Collapse
Affiliation(s)
- H G Heuft
- Virchow-Clinic, Department of Internal Medicine, Hematology/Oncology, Humboldt University, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Meincke H, Ebling DG, Heinze J, Tacke M, Böttner H. A photoelectrochemical study of anodic oxides on lead selenide surfaces in alkaline solutions. ACTA ACUST UNITED AC 1999. [DOI: 10.1007/s002160051461] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
25
|
Ross RS, Viazov S, Da Villa G, Schmitt U, Tacke M, Ofenloch-Haehnle B, Roggendorf M. Antibodies to the E2 protein of GB virus C/hepatitis G virus: low prevalence in Asian countries. Zentralbl Bakteriol 1998; 288:415-9. [PMID: 9861685 DOI: 10.1016/s0934-8840(98)80017-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
Abstract
Epidemiological investigations of GB virus C (GBV-C)/hepatitis G virus (HGV), an infectious agent discovered in 1995/1996, are facilitated by a recently developed immunoassay for the detection of antibodies to the viral envelope 2 protein (anti-E2). We used this assay to establish GBV-C/HGV prevalence in seven European, African, and Asian countries. A total of 1579 serum samples from healthy adults lacking prior exposure to known parenteral risk factors was screened. Anti-E2 positivity ranged from 13.6% (Italy) to 7.7% (Mauritius) in the European and African countries investigated. Anti-E2 prevalence was exceedingly low in the Philippines and Sri Lanka. This observation might be attributable to socio-economical and demographic factors.
Collapse
Affiliation(s)
- R S Ross
- Institute of Virology, University of Essen, Germany.
| | | | | | | | | | | | | |
Collapse
|
26
|
Tanaka E, Kiyosawa K, Shimoda K, Hino K, Tacke M, Schmolke S, Engel AM, Hess G. Evolution of hepatitis G virus infection and antibody response to envelope protein in patients with transfusion-associated non-A, non-B hepatitis. J Viral Hepat 1998; 5:153-9. [PMID: 9658367 DOI: 10.1046/j.1365-2893.1998.00095.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
The clinical significance and course of acute hepatitis G virus (HGV) infection were studied by measuring HGV RNA and antibody to HGV envelope protein E2 (HGV-E2 antibody). A total of 59 patients with transfusion-associated non-A, non-B hepatitis, who were followed-up for more than 1 year, were selected retrospectively. HGV RNA was measured by reverse transcriptase (RT) and nested polymerase chain reaction (PCR) was performed, using primer sets, in the 5'-non-coding region of the HGV genome. HGV-E2 antibody was measured by enzyme-linked immunosorbent assay (ELISA) using recombinant E2 protein. Of the 59 patients, 51 (86%) were infected with hepatitis C virus (HCV) and 12 (20%) were infected with HGV; 11 of the 12 with HGV infection were also infected with HCV. HGV viraemia was cleared during the follow-up period in seven of the 12 patients with HGV infection. All these seven patients seroconverted for HGV-E2 antibody just before or just after the clearance of HGV viraemia. In contrast, all five patients without clearance of HGV viraemia were negative for HGV-E2 antibody (P = 0.0013). Of seven patients with continuous HGV viraemia at 1 year from the onset of acute hepatitis, four with HCV RNA showed chronic elevation of alanine aminotransferase (ALT) but three without HCV RNA did not. The severity of acute hepatitis was similar between patients with both HGV and HCV infections and in those with HCV infection alone. The majority of patients with HGV infection cleared the virus during long-term follow-up. Appearance of HGV-E2 antibody was associated with the clearance of HGV viraemia. An abnormal ALT level was noted to depend on HCV infection but not on HGV infection in both the acute and chronic phases of transfusion-associated hepatitis.
Collapse
MESH Headings
- Acute Disease
- Adult
- Antigens, Viral/immunology
- Female
- Flaviviridae/genetics
- Flaviviridae/immunology
- Follow-Up Studies
- Hepacivirus
- Hepatitis Antibodies/blood
- Hepatitis Antibodies/immunology
- Hepatitis C/physiopathology
- Hepatitis C Antibodies/blood
- Hepatitis, Viral, Human/blood
- Hepatitis, Viral, Human/epidemiology
- Hepatitis, Viral, Human/immunology
- Hepatitis, Viral, Human/physiopathology
- Humans
- Male
- Middle Aged
- Prevalence
- RNA, Viral/blood
- Transfusion Reaction
- Viral Envelope Proteins/immunology
Collapse
Affiliation(s)
- E Tanaka
- Second Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto, Japan
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Schmolke S, Tacke M, Schmitt U, Engel AM, Ofenloch-Haehnle B. Identification of hepatitis G virus particles in human serum by E2-specific monoclonal antibodies generated by DNA immunization. J Virol 1998; 72:4541-5. [PMID: 9557757 PMCID: PMC109705 DOI: 10.1128/jvi.72.5.4541-4545.1998] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In order to elucidate the structure and morphology of hepatitis G virus (HGV), a recently isolated flavivirus, we generated a panel of eight monoclonal antibodies (MAbs) against the putative second envelope protein (E2) following DNA immunization. The MAbs were shown to be specific for four different epitopes on recombinant E2. MAb Mc6 was the only antibody able to detect the linear epitope LTGGFYEPL. In addition, Mc6 was able to immunoprecipitate viral particles in human blood samples as detected by reverse transcription-PCR amplification of HGV RNA. This precipitation could be competed by addition of saturating amounts of the linear peptide or abolished by addition of Nonidet P-40. We conclude that, albeit lacking the N-terminal sequence of a functional core protein, HGV builds classical viral particles displaying E2 envelope protein on their outer surfaces.
Collapse
Affiliation(s)
- S Schmolke
- Boehringer Mannheim GmbH, R&D Infectious Diseases, Penzberg, Germany
| | | | | | | | | |
Collapse
|
28
|
Heuft HG, Berg T, Schreier E, Kunkel U, Tacke M, Schwella N, Hopf U, Salama A, Huhn D. Epidemiological and Clinical Aspects of Hepatitis G Virus Infection in Blood Donors and Immunocompromised Recipients of HGV-Contaminated Blood. Vox Sang 1998. [DOI: 10.1046/j.1423-0410.1998.7430161.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
29
|
Ross RS, Viazov S, Schmitt U, Schmolke S, Tacke M, Ofenloch-Haehnle B, Holtmann M, Müller N, Da Villa G, Yoshida CF, Oliveira JM, Szabo A, Paladi N, Kruppenbacher JP, Philipp T, Roggendorf M. Distinct prevalence of antibodies to the E2 protein of GB virus C/hepatitis G virus in different parts of the world. J Med Virol 1998; 54:103-6. [PMID: 9496367 DOI: 10.1002/(sici)1096-9071(199802)54:2<103::aid-jmv6>3.0.co;2-a] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Since the identification of the new human virus, GB virus C (GBV-C)/hepatitis G-virus (HGV), in 1995/1996, reverse transcription polymerase chain reaction remained the sole available diagnostic tool for GBV-C/HGV infection. Recently, a serologic test based on the detection of antibodies to the putative envelope protein 2 (anti-E2) has been introduced. We used this assay for a seroepidemiological survey including 3,314 healthy individuals from different parts of the world, 123 patients from Germany who were suspected to have an increased risk of acquiring GBV-C/HGV infection, 128 multiple organ donors, and 90 GBV-C/HGV RNA positive persons. In European countries, anti-E2 seropositivity ranged from 10.9% (Germany) to 15.3% (Austria). In South Africa (20.3%) and Brazil (19.5%), even higher anti-E2 prevalence rates were recorded. In Asian countries like Bhutan (3.9%), Malaysia (6.3%), and the Philippines (2.7%), anti-E2 positivity was significantly lower. GBV-C/HGV anti-E2 prevalence in potential "risk groups," i.e., patients on hemodialysis and renal transplant recipients, did not vary significantly from anti-E2 seroprevalence in German blood donors. Anti-E2 and GBV-C/HGV RNA were found to be mutually exclusive, confirming the notion that anti-E2 has to be considered as a marker of past infection.
Collapse
Affiliation(s)
- R S Ross
- Institute of Virology, University of Essen, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Tanaka E, Tacke M, Kobayashi M, Nakatsuji Y, Kiyosawa K, Schmolke S, Engel AM, Hess G, Alter HJ. Past and present hepatitis G virus infections in areas where hepatitis C is highly endemic and those where it is not endemic. J Clin Microbiol 1998; 36:110-4. [PMID: 9431931 PMCID: PMC124818 DOI: 10.1128/jcm.36.1.110-114.1998] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/1997] [Accepted: 10/08/1997] [Indexed: 02/05/2023] Open
Abstract
We reported previously on an area in Japan where over 30% of the inhabitants were positive for hepatitis C virus (HCV) antibody. In the present study, clinical features of hepatitis G virus (HGV) infection in this area of high endemicity were compared to those in an area where HCV is not endemic. A total of 400 individuals were selected randomly from those who were medically screened for liver disease in 1993; 200 were from the high-endemicity area, and the other 200 were from the no-endemicity area. HGV RNA was measured by reverse transcription and PCR with primers in the 5' noncoding region. Antibody to HGV envelope protein E2 was measured by an enzyme-linked immunosorbent assay. Prevalence of any HGV marker in the high-endemicity area (32%) was significantly (P < 0.0001) higher than that in the no-endemicity area (6%); similar differences, 32% versus 3% (P < 0.0001), had been observed for HCV markers (HCV RNA and HCV antibody). In areas of both high and no endemicity, HCV markers were significantly more prevalent in individuals with any HGV marker than in those without HGV markers, and age-specific prevalence of HGV markers was distributed similarly to that of any HCV marker. Among possible routes of HGV transmission that were analyzed, folk medicine was significant in the high-endemicity area, but blood transfusion was the major route in the no-endemicity area. The rate of accompanying viremia in HGV infection (15%) was significantly lower than that in HCV infection (78%) (P < 0.0001). In conclusion, HGV infection was highly prevalent in the area of high HCV endemicity and was closely associated with HCV infection. HGV seemed to be transmitted via the practice of folk medicine as well as blood transfusion. HGV resulted in a chronic carrier state less frequently than did HCV.
Collapse
Affiliation(s)
- E Tanaka
- Second Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Tacke M, Schmolke S, Schlueter V, Sauleda S, Esteban JI, Tanaka E, Kiyosawa K, Alter HJ, Schmitt U, Hess G, Ofenloch-Haehnle B, Engel AM. Humoral immune response to the E2 protein of hepatitis G virus is associated with long-term recovery from infection and reveals a high frequency of hepatitis G virus exposure among healthy blood donors. Hepatology 1997; 26:1626-33. [PMID: 9398008 DOI: 10.1002/hep.510260635] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The second envelope protein (E2) of the hepatitis G virus (HGV) was expressed in Chinese hamster ovary (CHO) cells and showed a molecular weight of approximately 60 to 70 kd, with 15 to 25 kd of the size contributed by N-linked glycosylation. An enzyme-linked immunosorbent assay (ELISA) using HGV-E2 was developed to test for antibodies to this protein (anti-E2) in human sera. High sensitivity was achieved by developing monoclonal antibodies (mAbs) to HGV-E2, which were used as capture antibodies in the ELISA. Our studies revealed that 16% of healthy Spanish blood donors were exposed to HGV, indicating that additional routes of viral transmission besides parenteral exposure might exist. An even higher prevalence of exposure to HGV (52%-73%) was found in several groups at risk of parenteral exposure to infectious agents, i.e., intravenous drug users, transfusion history, hemophiliacs, and hepatitis C virus (HCV)-positive patients. Most anti-E2-positive patients were HGV-RNA-negative and vice versa, indicating an inverse correlation of these two viral markers. A panel of 16 posttransfusion patients followed for up to 16 years revealed that patients who develop an anti-E2 response become HGV-RNA-negative, while patients who do not develop anti-E2 are persistently infected. Immunity to HGV seems to be long-lasting, because circulating antibody to E2 could still be detected 14 years after seroconversion. Sequence comparisons showed that E2 is highly conserved among isolates collected worldwide, indicating that immune escape variants are not common in HGV infections. This reflects on a molecular level why HGV infections usually are cleared spontaneously by the host. However, possible mechanisms of HGV persistence, as found in some patients, remain to be elucidated.
Collapse
Affiliation(s)
- M Tacke
- Boehringer Mannheim GmbH, R & D Infectious Diseases, Penzberg, Germany
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Stark K, Meyer CG, Tacke M, Schwarz A, Braun C, Huzly D, Engel AM, May J, Bienzle U. Hepatitis G virus RNA and hepatitis G virus antibodies in renal transplant recipients: prevalence and risk factors. Transplantation 1997; 64:608-12. [PMID: 9293874 DOI: 10.1097/00007890-199708270-00011] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Hepatitis G virus (HGV/GBV-C) RNA indicating current infection has been frequently isolated from the sera of transplant recipients and other multitransfused individuals. Lifetime exposure to the virus, however, is unknown. We carried out a study to determine the prevalence and risk factors of HGV antibodies and of HGV RNA among renal transplant recipients, and to investigate possible associations between HGV RNA and immunosuppressive treatment. METHODS HGV RNA was detected by reverse transcriptase-polymerase chain reaction, and HGV antibodies (anti-E2) by a newly developed immunoassay. To assess risk factors for HGV exposure, univariate and multivariate analysis was performed. RESULTS Of the 221 patients, 14% were HGV RNA positive and 40% had HGV antibodies. Both HGV RNA and anti-HGV were present in only two individuals. Thus, the overall HGV exposure prevalence was 53%. It increased significantly with the number of blood transfusions. In logistic regression, the adjusted HGV exposure prevalence odds ratio was 5.7 (95% confidence interval [CI]: 2.2-15) among patients with > or =10 transfusions (baseline: no transfusions). Other independent risk factors were a longer duration of hemodialysis and a longer time interval since transplantation. HGV viremia was not associated with the type of immunosuppressive treatment. Alanine aminotransferase levels were not significantly increased among HGV RNA-positive patients. CONCLUSIONS Much higher proportions of renal transplant recipients were exposed to HGV than is suggested by HGV RNA detection alone. The majority of infected individuals apparently eliminate the virus over time. Contaminated blood transfusions have to be regarded as a main risk factor for HGV infection.
Collapse
Affiliation(s)
- K Stark
- Institute of Tropical Medicine, Berlin, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Tacke M, Schmolke S, Schlueter V, Kiyosawa K, Stark K, Ofenloch BH, Hess G, Engel A. Antibodies to hepatitis G virus E2 protein (HGV-E2) indicate recovery from HGV infections. Immunol Lett 1997. [DOI: 10.1016/s0165-2478(97)86194-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
34
|
Abstract
BACKGROUND A flavivirus designated hepatitis G virus (HGV) has been isolated from the serum of patients with non-A-E hepatitis. Hitherto, the presence of HGV RNA in serum has been detected with the reverse transcription-polymerase chain reaction (RT-PCR) amplification method. We have now developed an immunoassay for antibodies against an HGV protein. METHODS Recombinant HGV envelope protein E2 was used as antigen in an ELISA. 80 blood donors, 99 intravenous-drug users, and 11 patients with acute post-transfusion hepatitis were tested for antibodies to E2. The HGV-RNA status was assessed by RT-PCR. FINDINGS Anti-E2 seroprevalence was 9% among the blood donors and 41% among the drug users; HGV-RNA prevalence was 2.5% and 38%, respectively. Whereas anti-E2 prevalence increased with the duration of drug use, HGV-RNA prevalence declined in parallel. In each group, the presence of anti-E2 and HGV RNA was almost mutually exclusive: none of the blood donors and only 4% of the drug users were positive for both markers at the same time. Of the 11 post-transfusion patients--who were all HGV-RNA positive and anti-E2 negative at the onset of disease--four developed antibodies to E2 during the following year, and two of the four subsequently became HGV-RNA negative. INTERPRETATION We conclude that a humoral immune response to E2 is associated with loss of detectable HGV viraemia. Thus, E2-specific antibodies might serve as a useful marker for diagnosing recovery from HGV infections. The immunoassay we describe should facilitate investigation of suspected infections and may be helpful in the elucidation of the clinical significance of HGV.
Collapse
Affiliation(s)
- M Tacke
- Boehringer Mannheim GmbH, Penzberg, Germany
| | | | | | | | | | | | | |
Collapse
|
35
|
Tacke M, Hanke G, Hanke T, Hünig T. CD28-mediated induction of proliferation in resting T cells in vitro and in vivo without engagement of the T cell receptor: evidence for functionally distinct forms of CD28. Eur J Immunol 1997; 27:239-47. [PMID: 9022025 DOI: 10.1002/eji.1830270136] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
JJ316 and JJ319 are rat CD28-specific monoclonal antibodies (mAb) of the gamma1 kappa isotype with identical co-stimulatory potency. At a concentration 100-1000-fold higher than that required for co-stimulation, JJ316, but not JJ319 induces massive proliferation of all T cell subsets in vitro without T cell receptor (TCR) triggering. "Direct" stimulation by JJ316 is fully blocked by JJ319, indicating that it is not due to cross-reactivity of JJ316 with the TCR complex or other activating receptors. JJ316 binds much more slowly to primary T cells than JJ319, whereas both antibodies bind with similar kinetics to CD28-transfected L-929 cells, suggesting that JJ316 binding to T cells requires redistribution or a conformational change of CD28. In vivo, JJ316 but not JJ319 induces rapid and transient proliferation of most CD4 T cells and, indirectly, of B cells. These data show that TCR engagement is not an absolute prerequisite either in vitro or in vivo for the induction of T cell proliferation through CD28 and suggest that mAb JJ316 is able to stimulate resting T cells directly by recruiting CD28 molecules from an inactive to an active form.
Collapse
Affiliation(s)
- M Tacke
- Institute for Virology and Immunobiology, University of Würzburg, Germany
| | | | | | | |
Collapse
|
36
|
Tacke M, Engel AM, Schlüter V, Schmolke S, Ofenloch-Haehnle B. Diagnosis of hepatitis G virus infections. Journal of Microbiological Methods 1996. [DOI: 10.1016/0167-7012(96)83738-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
37
|
Tacke M, Clark GJ, Dallman MJ, Hünig T. Cellular distribution and costimulatory function of rat CD28. Regulated expression during thymocyte maturation and induction of cyclosporin A sensitivity of costimulated T cell responses by phorbol ester. The Journal of Immunology 1995. [DOI: 10.4049/jimmunol.154.10.5121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Abstract
CD28 has been identified in man and mouse as a potent costimulatory receptor on T cells. We have generated a mAb, called JJ319, to rat CD28 and show that it is expressed on virtually all peripheral rat alpha beta and on most gamma delta T cells, and on about half of NK cells. In contrast to the mouse but as in humans, most immature CD4+8+TCRlow thymocytes express little or no CD28, whereas CD28 expression is high on TCRintermediate and TCRhigh cells. mAb JJ319 very effectively costimulates T cell proliferation and IL-2 secretion by resting rat T cells. In contrast to results obtained in mice and humans, phorbol ester did not synergize in T cell activation with CD28-specific mAb but even induced sensitivity to cyclosporin A in T cell cultures that were optimally costimulated by mAbs to the TCR and to CD28. This result points to a novel effect of protein kinase activation by phorbol ester on signal transduction by TCR plus CD28 costimulation which only becomes apparent if, as in the rat, the TCR-mediated signal cannot be replaced by phorbol ester.
Collapse
Affiliation(s)
- M Tacke
- Institute for Virology and Immunobiology, University of Würzburg, Germany
| | - G J Clark
- Institute for Virology and Immunobiology, University of Würzburg, Germany
| | - M J Dallman
- Institute for Virology and Immunobiology, University of Würzburg, Germany
| | - T Hünig
- Institute for Virology and Immunobiology, University of Würzburg, Germany
| |
Collapse
|
38
|
Tacke M, Clark GJ, Dallman MJ, Hünig T. Cellular distribution and costimulatory function of rat CD28. Regulated expression during thymocyte maturation and induction of cyclosporin A sensitivity of costimulated T cell responses by phorbol ester. J Immunol 1995; 154:5121-7. [PMID: 7730618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
CD28 has been identified in man and mouse as a potent costimulatory receptor on T cells. We have generated a mAb, called JJ319, to rat CD28 and show that it is expressed on virtually all peripheral rat alpha beta and on most gamma delta T cells, and on about half of NK cells. In contrast to the mouse but as in humans, most immature CD4+8+TCRlow thymocytes express little or no CD28, whereas CD28 expression is high on TCRintermediate and TCRhigh cells. mAb JJ319 very effectively costimulates T cell proliferation and IL-2 secretion by resting rat T cells. In contrast to results obtained in mice and humans, phorbol ester did not synergize in T cell activation with CD28-specific mAb but even induced sensitivity to cyclosporin A in T cell cultures that were optimally costimulated by mAbs to the TCR and to CD28. This result points to a novel effect of protein kinase activation by phorbol ester on signal transduction by TCR plus CD28 costimulation which only becomes apparent if, as in the rat, the TCR-mediated signal cannot be replaced by phorbol ester.
Collapse
Affiliation(s)
- M Tacke
- Institute for Virology and Immunobiology, University of Würzburg, Germany
| | | | | | | |
Collapse
|
39
|
Mitnacht R, Tacke M, Hünig T. Expression of cell interaction molecules by immature rat thymocytes during passage through the CD4+8+ compartment: developmental regulation and induction by T cell receptor engagement of CD2, CD5, CD28, CD11a, CD44 and CD53. Eur J Immunol 1995; 25:328-32. [PMID: 7533082 DOI: 10.1002/eji.1830250204] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Rat thymocytes of the T cell receptorlow (TcRlow) CD4+8+ subset which is the target of repertoire selection are heterogeneous with respect to expression of the cell interaction (CI) molecules CD2, CD5, CD11a/CD18 (LFA-1), CD28 and CD44. We show that this heterogeneity is due to the developmental regulation of these CI molecules during passage through the CD4+8+ compartment, and to up-regulation by TcR engagement. Thus, cohorts of CD4+8+ cells differentiating synchronously in vitro from their direct precursors, the immature CD4-8+ cells, were homogeneous with regard to CI molecule expression. Upon entry into the CD4+8+ compartment, they expressed relatively high levels of CD2 and CD44, and moderate levels of CD5, CD28 and CD11a. CD2, CD28 and CD44 were slightly down-regulated during the following 2 days, whereas CD5 slightly increased and CD11a remained constant. TcR stimulation using immobilized monoclonal antibodies resulted in rapid and dramatic up-regulation of CD2, CD5 and CD28 and, to a lesser extent, of CD11a and CD44. Finally CD53, a triggering structure absent from unstimulated CD4+8+ thymocytes was also rapidly induced by TcR stimulation. Inclusion of interleukin (IL)-2, IL-4, or IL-7 in this in vitro differentiation system did not affect the levels of CI molecules studied. Since the high levels of CI molecules induced by TcR-stimulation correspond to those found in vivo on TcRintermediate thymocytes known to be undergoing repertoire selection, these results suggest that upregulation of CI molecules by TcR engagement provides a mechanism by which thymocytes that have entered the selection process gain preferential access to further interactions with stromal and lymphoid cells in the thymus.
Collapse
Affiliation(s)
- R Mitnacht
- Institut für Virologie und Immunbiologie, Universität Würzburg, Germany
| | | | | |
Collapse
|
40
|
Abstract
Histological sections of formalin fixed, paraffin-embedded tissue comprising 195 specimens of human lung carcinomas were Feulgen stained. The nuclei of the histomorphological images were segmented using an automated image analyzing system, and the attributed minimum spanning trees (MST) were calculated. Features related to the DNA-content of the nuclei (integrated optical density (IOD), IOD-entropy, S-phase related fraction, percentage > 5C, etc.), and structural parameters (minimum distance between tumor cell nuclei, minimum distance between tumor cells and neighboring lymphocytes, MST-entropy, MST-current of entropy (entropiefluss), distance between neighboring proliferating tumor cells, etc.) were measured. The following results were obtained: the measured IOD and MST features showed significant differences between the primary carcinomas and metastatic carcinomas in the intrapulmonary lymph nodes. The survival of patients was remarkably improved if the carcinomas displayed a low S-phase related fraction, a low percentage of tumor cells > 5C, a low number of stem lines, and a low MST-current of entropy.
Collapse
Affiliation(s)
- K Kayser
- Department of Pathology, Thoraxklinik, Heidelberg, FRG
| | | | | | | |
Collapse
|
41
|
Messica A, Greenstein A, Katzir A, Schiessl U, Tacke M. Fiber-optic evanescent wave sensor for gas detection. Opt Lett 1994; 19:1167-1169. [PMID: 19844565 DOI: 10.1364/ol.19.001167] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A novel fiber-optic evanescent wave sensor is presented. The sensor, composed of a lead salt tunable infrared laser and a multimode uncladded silver halide infrared optic fiber, was used for rapid measurement of sulfur hexafluoride pressures at a few-percent detection limit. High-precision detection and identification of a large variety of gases are possible.
Collapse
|
42
|
Kayser K, Liewald F, Kremer K, Tacke M, Storck M, Faber P, Bonomi P. Alteration of integrated optical density and intercellular structure after induction chemotherapy and survival in lung carcinoma patients treated surgically. Anal Quant Cytol Histol 1994; 16:18-24. [PMID: 8011037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Histologic sections of formalin-fixed, paraffin-embedded tissue consisting of 53 surgical specimens, 48 biopsy specimens and 29 intrapulmonary lymph nodes of human non-small cell lung carcinoma were Feulgen stained. The biopsy specimens were obtained before and the surgical specimens after induction chemotherapy (down staging). The integrated optical density (IOD) of tumor cell nuclei was measured using an automated image analysis system, and the attributed minimum spanning trees (MSTs) were computed. The measured features included IOD (DNA content of the nuclei), IOD entropy, S-phase-related fraction (SRF), percentage of tumor cells with an IOD > 5C (P5C), standard deviation of IOD and structural parameters (minimum distance between neighboring tumor cell nuclei, minimum distance between tumor cell nuclei and neighboring lymphocytes, MST entropy, minimum distance between neighboring proliferating tumor cell nuclei, etc.). The measured IOD and MST features showed significant differences in the biopsy specimens as compared to those measured in the surgically excised carcinomas and those growing in the intrapulmonary lymph nodes (lymph node metastases). After down staging, the SRF was significantly diminished, and the percentage of cells with an IOD > 5C increased (P < .05). The survival of patients was remarkably improved if both the carcinomas before and after induction chemotherapy displayed a low SRF, a low number of stemlines and low MST entropy.
Collapse
Affiliation(s)
- K Kayser
- Department of Pathology, Thoraxklinik, Heidelberg, Germany
| | | | | | | | | | | | | |
Collapse
|
43
|
Kayser K, Kremer K, Tacke M. [DNA and MST entropy and current of entropy. New parameters of tumor biological characterization]. Zentralbl Pathol 1994; 139:427-31. [PMID: 7512821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The clinical significance of the entropy of the integrated optical density E (IOD) and the corresponding entropiefluss EF (IOD) is discussed as well as the structural entropy E (MST) and its entropiefluss EF (MST). The E (IOD) is based upon the formula given by Stenkvist and Strande. It describes the statistical entropy of the DNA distribution of tumor cell nuclei; the E (MST) is based upon differences in IOD and distance between neighboring tumor cell nuclei and describes the deviation of tumor structure from a "biological constant" structure. The entropiefluss measures the current of entropy or irreversibly created heat which has to be removed through the surface of the tumor. It is a universally valid description of a thermodynamically open system and measures the distance of such a system from its equilibrium stage. The clinical significance of these parameters is tested on 241 specimens of human lung carcinomas and intrapulmonary metastases of extrapulmonary malignancies. The surgical specimens were fixed with buffered formalin. Histological sections cut from paraffin-embedded tissue were FEULGEN stained. The nuclei of the histomorphological images were segmented using an automated image analyzing system, and the attributed minimum spanning trees (MST) were calculated. The following results were obtained: The measured E (IOD) and E (MST) showed significant differences in the primary carcinomas compared to those measured in intrapulmonary lymph node metastases or intrapulmonary metastases. The survival of patients was remarkably improved if the carcinomas displayed a low E (MST), EF (IOD), and EF (MST).
Collapse
Affiliation(s)
- K Kayser
- Abteilung für Pathologie, Thoraxklinik, Heidelberg, Deutschland
| | | | | |
Collapse
|
44
|
Kayser K, Stute H, Tacke M. Minimum spanning tree, integrated optical density and lymph node metastasis in bronchial carcinoma. Anal Cell Pathol 1993; 5:225-34. [PMID: 8363983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Surgical specimens comprising 80 primary lung carcinoma (lobes and lungs) were expanded by insufflation of air into the main bronchi, and fixed with buffered formalin for 24 h. After the usual tissue procedures, 3-4 microns thick histological sections of the tumour mass were Feulgen stained and various nuclear features such as integrated optical density (IOD), area, form factor, etc. were measured using an automated image analysing system (VISIAC). The geometrical centres of the nuclei were defined as vertices and the corresponding minimum spanning tree (MST) was calculated according to the distance between the vertices. The tumour mass was measured by serial sections of the surgical specimens; the lymph node stage was defined according to the rules of the UICC. Non-tumour infiltrated lymph nodes of the same case served as controls for the IOD and MST. The results revealed a DNA index of 1.1-3.0, a malignancy index (Böcking) 0.90-1.08 and a percentage of S-phases 10-23% (confidence limits). Only 19% of the bronchial carcinoma were found to be not aneuploid. Based upon the weighted MST, the distance of neighbouring cells, the IOD of the centre cells and IOD/area of neighbouring cells revealed statistically significant differences between tumours with and without lymph node metastases. The more advanced the lymph node stage, the 'closer' was the 'packing' of the tumour cells.
Collapse
Affiliation(s)
- K Kayser
- Department of Pathology, Thoraxklinik, Heidelberg, Germany
| | | | | |
Collapse
|
45
|
Kayser K, Kremer C, Tacke M. Integrated optical density and entropiefluss (current of entropy) in bronchial carcinoma. In Vivo 1993; 7:387-91. [PMID: 8218984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Histological sections of formalin-fixed, paraffin-embedded bronchial carcinomas comprising 241 surgical specimens (lobes and lungs) were Feulgen stained. The integrated optical density of the nuclei (IOD) and the minimum distance between their centers of gravity (DG) was measured with an automated image analyzing system consisting of a TV camera connected to a personal computer via a frame grapper. Intratumorous lymphocytes served as DNA standard (2C peak), and 300 nuclei were measured at minimum. The entropy of the IOD, the percentage of S-phases (PS) of tumor cells with an IOD > 3C and > 5C, and the 2CV mean standard deviation were measured. According the theory of thermodynamically open systems, the entropiefluss (current of entropy) was defined by the gradient IOD/time through the surface of the tumors which can be approximated by the formula IOD*PS*DG/tumor volume. The following results were obtained: a) IOD of bronchial carcinoma is not associated with tumor size or lymph node infiltration (pT and pN stage). b) The minimum distance between tumor cells decreases with increasing tumor stage and increasing lymph node stage (pT, pN stage). c) The entropiefluss is low in limited and advanced tumor stages, and highest in tumors at moderately progressive tumor stages (pT2, pT3, pN1, pN2). Thus, in accordance with the theory of thermodynamically open systems, the entropiefluss reflects the "biological activity" of bronchial carcinoma.
Collapse
Affiliation(s)
- K Kayser
- Department of Pathology, Thoraxklinik, Heidelberg, Germany
| | | | | |
Collapse
|
46
|
|
47
|
Bunimovich D, Kellner R, Krska R, Mesica A, Paiss I, Schiesl U, Tacke M, Taga K, Katzir A. A system for monitoring & control of processes based on IR fibers and tunable diode lasers. J Mol Struct 1993. [DOI: 10.1016/0022-2860(93)80095-d] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
48
|
Tacke M, Klein C, Stufkens D, Oskam A. Photochemistry of Cp2Ti(CO)2 and Cp2Ti(N3)2 in solid matrices and in solution at low temperatures. J Organomet Chem 1993. [DOI: 10.1016/0022-328x(93)83057-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
49
|
|
50
|
Tacke M, Yang Y, Steup M. Multiplicity of soluble glucan-synthase activity in spinach leaves: Enzyme pattern and intracellular location. Planta 1991; 185:220-226. [PMID: 24186345 DOI: 10.1007/bf00194064] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/1990] [Accepted: 04/15/1991] [Indexed: 06/02/2023]
Abstract
Buffer-extractable proteins from leaves of Spinacia oleracea L. were separated by non-denaturing polyacrylamide gel electrophoresis. Gels were stained for adenosine diphosphoglucose (ADPglucose)-dependent glucan-synthase (GS) activity (EC 2.4.1.21). Three major forms of activity were observed. No staining was detectable when ADPglucose was replaced by an equimolar concentration of either uridine, guanosine or cytosine diphosphoglucose. Two of the three GS forms exhibited both primed and citrate-stimulated unprimed activity whereas one enzyme form was strictly dependent upon the presence of an exogenous glucan. For intracellular localization, mesophyll protoplasts and intact chloroplasts were isolated and their enzyme pattern was compared with that of the leaf extract. Intactness and purity of the chloroplast preparations were ascertained by polarographic measurement of the ferricyanide- or CO2-dependent oxygen evolution, by determination of marker-enzyme activities, and by electrophoretic evaluation of the content of chloroplast- and cytosol-specific glucanphosphorylase forms (EC 2.4.1.1). The three GS forms were present in mesophyll protoplasts. Intact chloroplasts possessed both primer-independent enzyme forms but lacked the primer-dependent one. The latter form was enriched in supernatant fractions of leaf homogenates when the intact chloroplasts had been pelleted by centrifugation. Thus, in spinach-leaf mesophyll cells soluble ADPglucose-dependent GS is located both inside and outside the chloroplast.
Collapse
Affiliation(s)
- M Tacke
- Institut für Botanik der Westfälischen Wilhelms-Universität Münster, Schlossgarten 3, W-4400, Münster, Germany
| | | | | |
Collapse
|