Wolfgang Walcher

Publications of Wolfgang Walcher

• Measurement of cell death by oxidative stress in three-dimensional spheroids from trophoblast and in fragments of decidua tissue.

  Authors: Regine-Susanne Theuerkauf, Helmut Ahammer, Monika Siwetz, Christine Helige, Gottfried Dohr, Wolfgang Walcher, José Ramón Palacio, Paz Martinez, Peter Sedlmayr

  Journal of reproductive immunology. 03/2010; 85(1):63-70.

  We report a new morphometric method for measurement of the amount of cell death in three-dimensional multicellular spheroids of the trophoblast-like cell line AC1-M59 and of cultured pieces ofWe report a new morphometric method for measurement of the amount of cell death in three-dimensional multicellular spheroids of the trophoblast-like cell line AC1-M59 and of cultured pieces of decidua tissue (decidua spheroids) in response to a cytotoxic agent. The viability of the spheroids was assessed by adding propidium iodide to the culture medium at the end of the toxic treatment. On fluorescence and brightfield images of serial cryosections the areas of propidium iodide fluorescence and the entire corresponding spheroids were measured by applying digital image processing and ratiometrical quantification. As an example, we evaluated the cytotoxic effect of hydrogen peroxide on both types of spheroids. The relative potency of hydrogen peroxide to induce tissue damage was assessed quantitatively for determination of the minimal concentration that leads to an increase in cytotoxicity. The method presented suggests general applicability for in vitro determination of toxicity against tissues.

• Automatic retrieval of single microchimeric cells and verification of identity by on-chip multiplex PCR.

  Authors: Thomas Kroneis, Liat Gutstein-Abo, Kristina Kofler, Michaele Hartmann, Petra Hartmann, Marianna Alunni-Fabbroni, Wolfgang Walcher, Gottfried Dohr, Erwin Petek, Esther Guetta, Peter Sedlmayr

  Journal of cellular and molecular medicine. 06/2009;

  ABSTRACT The analysis of rare cells is not an easy task. This is especially true when cells representing a fetal microchimerism are to be utilized for the purpose of non-invasive prenatal diagnosisABSTRACT The analysis of rare cells is not an easy task. This is especially true when cells representing a fetal microchimerism are to be utilized for the purpose of non-invasive prenatal diagnosis since it is both imperative and difficult to avoid contaminating the minority of fetal cells with maternal ones. Under these conditions, even highly specific biochemical markers are not perfectly reliable. We have developed a method to verify the genomic identity of rare cells that combines automatic screening for enriched target cells (based on immunofluorescence labelling) with isolation of single candidate microchimeric cells (by laser microdissection and subsequent laser-catapulting) and low-volume on-chip multiplex PCR for DNA fingerprint analysis. The power of the method was tested by using samples containing mixed cells of related and non-related individuals. Single cell DNA fingerprinting was successful in 74% of the cells analyzed (55/74) with a PCR efficiency of 59.2% (860/1452) for heterozygous loci. The identification of cells by means of DNA profiling was achieved in 100% (12/12) of non-related cells in artificial mixtures and in 86% (37/43) of cells sharing a haploid set of chromosomes and was performed on cells enriched from blood and cells isolated from tissue. We suggest DNA profiling as a standard for the identification of microchimerism on a single cell basis.

• Adolescent primiparas: changes in obstetrical risk between 1983-1987 and 1999-2005.

  Authors: Willibald Zeck, Wolfgang Walcher, Karl Tamussino, Uwe Lang

  The journal of obstetrics and gynaecology research. 05/2008; 34(2):195-8.

  AIMS: Teenage pregnancies have always been considered at increased risk for obstetric complications. Deliveries in adolescent primiparas in the 5-year time periods 1983-1987 and 1999-2005 wereAIMS: Teenage pregnancies have always been considered at increased risk for obstetric complications. Deliveries in adolescent primiparas in the 5-year time periods 1983-1987 and 1999-2005 were compared against each other, the general population and against primiparas aged 20-29 years in order to reveal trends and differences in obstetric outcome. METHODS: A total of 186 primiparas delivering at an age of 17 or less between October 1999 and October 2005 were compared with 353 adolescent primiparas delivered between 1983 and 1987. Type of delivery and complications such as low birthweight, pre-eclampsia, breech presentation and third stage complications were studied. RESULTS: The percentage of adolescents in the overall obstetric population decreased. The cesarean section rate remained the same in the adolescents while increasing in the general population. Rates of low birthweight and operative vaginal delivery increased in the adolescent group and overall. Third stage complications (abnormally adherent or incomplete placentas) decreased in both groups. There were no intrauterine fetal deaths in adolescent pregnancies in either time period. Other obstetric variables were unchanged in the adolescent as well as in the general population between 1999 and 2005. When comparing the adolescents' outcome with the outcome of the 20-29-year-old primiparas between 1999 and 2005, it was noted that the rates of abstracted obstetric variables were higher in the population of the 20-29-year-olds. CONCLUSIONS: The obstetric outcome of adolescent pregnancies has remained favorable over the last 18 years. We do not consider adolescence as an obstetrical risk. We suggest that adolescent pregnancy is more a public health issue than a clinical problem.

• External cephalic version in singleton pregnancies at term: a retrospective analysis.

  Authors: Willibald Zeck, Wolfgang Walcher, Uwe Lang

  Gynecologic and obstetric investigation. 02/2008; 66(1):18-21.

  BACKGROUND/AIMS: The outcomes of external cephalic versions (ECV) performed at the University Hospital Graz in Austria were analyzed to determine to what extent the cesarean section rate can beBACKGROUND/AIMS: The outcomes of external cephalic versions (ECV) performed at the University Hospital Graz in Austria were analyzed to determine to what extent the cesarean section rate can be reduced by an ECV program. METHODS: All women who were admitted to the hospital with breech presentation at 37 weeks or later and underwent an attempt of ECV between 2002 and 2004 were recorded and retrospectively analyzed. RESULTS: Of 136 cases 51% were successful. Among these, the cesarean section rate was 13%. The cesarean section rate among all not successful cases was 82%. Of the successful cases which remained in cephalic presentation 92% were delivered vaginally and 5 were delivered by cesarean section. The cesarean section rate (8%) was slightly higher than in fetuses with cephalic presentation observed at the onset of contractions in 2004 (5.9%). No maternal or fetal complications or side effects occurred. CONCLUSION: Successful ECV beyond 37 weeks of gestation significantly decreases the cesarean section rate. ECV reduces the cesarean section rate among breech positions and decreases the risks related to breech delivery, when correctly performed and adequately monitored. ECV reduces higher costs connected with cesarean section.

• Expression of functional Fas ligand in choriocarcinoma.

  Authors: Astrid Hammer, Michaele Hartmann, Peter Sedlmayr, Wolfgang Walcher, Gaby Kohnen, Gottfried Dohr

  American journal of reproductive immunology (New York, N.Y. : 1989). 11/2002; 48(4):226-34.

  PROBLEM: In the course of pregnancy, fetal trophoblast cells and in that of choriocarcinoma-etiology, trophoblast derived tumor cells, invade the uterine mucosa without causing rejection by decidualPROBLEM: In the course of pregnancy, fetal trophoblast cells and in that of choriocarcinoma-etiology, trophoblast derived tumor cells, invade the uterine mucosa without causing rejection by decidual leukocytes. Fas ligand (FasL, CD95L, APO-IL), a central regulator of the immune system, has been implicated in the maintenance of immune privileged sites, such as the eye, the testis and the pregnant uterus by inducing apoptosis in activated infiltrating leukocytes. In normal pregnancy FasL, which is expressed by trophoblast cells, appears to contribute to the immune privilege of the pregnant uterus. As choriocarcinoma derives from trophoblast we wanted to assess the expression of FasL in this tissue. METHOD OF STUDY: Immunohistochemistry, immunofluorescence, TUNEL-assay, Western blotting, coculture experiments and flourescence-associated cell sorter-analysis were the techniques used. RESULTS: Expression of FasL was found on cells of choriocarcinoma in paraffin sections in situ and on three choriocarcinoma cell lines such as JEG-3, JAR and BeWo. These results were confirmed by Western blotting. In coculture experiments choriocarcinoma cells induced apoptosis in a Jurkat cell line - sensitive to FasL mediated killing. However, when the Jurkat cells were pre-incubated with a Fas-blocking monoclonal antibody, apoptosis was abolished to a great extent. CONCLUSION: Our findings show that choriocarcinoma cells express FasL and this aforementioned molecule is biologically active. We assume that FasL expression on choriocarcinoma cells may contribute to control of anti-tumor responses by inducing apoptosis in activated Fas bearing leukocytes.

• Absence of HLA-G expression in macrophages of human decidua.

  Authors: Peter Sedlmayr, Pedro Morales, Silvia Trummer, Karin Wascher, Dagmar Azzola, Astrid Blaschitz, Astrid Hammer, Wolfgang Walcher, Reinhold Wintersteiger, Gottfried Dohr

  American journal of reproductive immunology (New York, N.Y. : 1989). 09/2002; 48(2):96-102.

  PROBLEM: Macrophages - together with natural killer (NK) cells - constitute the majority of bone marrow derived infiltrating cells in the decidua. As interferon-gamma (IFN-gamma), a cytokine producedPROBLEM: Macrophages - together with natural killer (NK) cells - constitute the majority of bone marrow derived infiltrating cells in the decidua. As interferon-gamma (IFN-gamma), a cytokine produced by NK cells, has been reported to induce expression of human leukocyte antigen (HLA-G) in monocytic cells, suggesting expression of HLA-G on decidua macrophages potentially stimulated by IFN-gamma, the question arises whether decidua macrophages in normal pregnancy express HLA-G. METHOD OF STUDY: The study was based on immunohistochemistry and flow cytometry. In order to exclude that potentially elusive soluble HLA-G was not detected by immunohistochemistry, we performed in addition RT-PCR of flow-sorted decidua macrophages. RESULTS: Our findings indicate that HLA-G is not present on macrophages of first trimester or term decidua in either membrane-bound or soluble form. Transcripts for soluble HLA-G1 and -G2 were not detected. CONCLUSIONS: We exclude a role of HLA-G on the surface of decidua macrophages or of soluble HLA-G1 or -G2 as a secretory product of decidua macrophages with regard to interaction with HLA-G receptors present in or outside the decidua.