Angela Köninger

CD133 allows elaborated discrimination and quantification of haematopoietic progenitor subsets in human haematopoietic stem cell transplants

The success of haematopoietic stem cell (HSC) transplantation largely depends on numbers of transplanted HSCs, which reside in the CD34+ populations of bone marrow (BM), peripheral blood stem cells (PBSC) and umbilical cord blood (UCB). More specifically HSCs reside in the CD38low/− subpopulation, which cannot be objectively discriminated from mature CD34+ CD38+ progenitors. Thus, better marker combinations for the quantification of more primitive haematopoietic stem and progenitor cells in transplants are required. Recently, by combining CD34 and CD133 we could clearly distinguish CD133+ CD34+ multipotent and lympho‐myeloid from CD133low CD34+ erythro‐myeloid progenitors in UCB samples. To qualify the assessment of CD133 for routine quality control of adult HSC sources, we analysed the developmental potentials of CD133+ and CD133low subpopulations in BM and PBSC. Similar to UCB, CD133 expression objectively discriminated functionally distinct subpopulations in adult HSC sources. By implementing anti‐CD45RA staining, which separates multipotent (CD133+ CD34+ CD45RA−) from lympho‐myeloid (CD133+ CD34+ CD45RA+) progenitor fractions, UCB was found to contain 2–3 times higher multipotent progenitor frequencies than BM and PBSC. To test for the consistency of CD133 expression, we compared CD133+ CD34+ contents of 128 UCB samples with maternal and obstetrical factors and obtained similar correlations to related studies focusing on CD34+ cell contents. In conclusion, implementation of anti‐CD133 staining into existing routine panels will improve the quality control analyses for HSC transplants.

Predictive markers for the FSH sensitivity of women with polycystic ovarian syndrome

STUDY QUESTION Do parameters which are involved in pathogenesis of polycystic ovarian syndrome (PCOS) predict the dosage of recombinant FSH required to achieve monofollicular development for ovulation induction? SUMMARY ANSWER Anti-Mullerian hormone (AMH) appeared to be an independent predictor of the required dosage of FSH to achieve monofollicular development for ovulation induction in a study sample of clomiphene-resistant PCOS patients. WHAT IS KNOWN ALREADY AMH plays a key role in the pathogenesis of PCOS. This is the first study that has evaluated the association between AMH and the required FSH dosage to achieve the development of a large follicle of at least 18 mm, in the presence of additional predictors of ovarian responsiveness. In the few studies to date which have evaluated predictors of ovarian responsiveness in PCOS patients, fasting insulin has been shown to be a significant predictor. STUDY DESIGN, SIZE, DURATION A total of 48 infertile PCOS patients aged 18-43 years were enrolled in this prospective, observational study between 2009 and 2013. Study participants received between one and six cycles of ovarian stimulation with recombinant FSH using a step-up protocol. The mean total FSH dosage per cycle for reaching a monofollicular development for ovulation induction was evaluated to investigate its association with AMH, LH, FSH, LH/FSH-ratio, sex hormone-binding globulin (SHBG), androstendione, testosterone, free testosterone index, antral follicle count, ovarian volume, body mass index (BMI) and the age of patients. PARTICIPANTS/MATERIALS, SETTING, METHODS We used AMH-Gen-II ELISA (Beckman Coulter, Immunotech, Webster, TX, USA) for the assessment of AMH levels. Crude and multiple linear regression models were fitted to explore potential predictors of the required FSH dosage. MAIN RESULTS AND THE ROLE OF CHANCE An interquartile range (IQR) increase in AMH was associated with a 51.4% [95% confidence interval (CI): 24.7-79.0%; P = 0.0003] increase in the mean total FSH dosage per cycle (in IU) in a crude regression model, corresponding to a 7.2% increase in the mean total FSH dosage per cycle per ng/ml AMH. Adjustment for BMI augmented the effect of AMH, with a 58.3% (95% CI: 33.2-84.2%; P = 1.8 × 10(-5)) increase in FSH dosage per IQR AMH (corresponding to an 8.2% increase per ng/ml AMH) and a 46.2% (95% CI: 16.5-76.6%; P = 0.003) increase per IQR BMI (corresponding to a 3.7% increase per kg/m(2)). AMH was the only independent variable for which the effect on FSH dosage was statistically significant in the crude regression model as well as after adjustment for other promising predictors. The association of BMI with FSH dosage was statistically significant while adjusted for AMH, but not in the crude model. LIMITATIONS, REASONS FOR CAUTION The impact of metabolic parameters such as insulin resistance on the reported association between AMH and FSH dosage was not assessed. WIDER IMPLICATIONS OF THE FINDINGS Knowledge about the predictors of ovarian sensitivity to FSH can facilitate a physicians decision-making in providing the optimal infertility therapy for PCOS patients. STUDY FUNDING/COMPETING INTERESTS Funding was provided by the University Hospital of Essen.

Serum concentrations of afamin are elevated in patients with polycystic ovary syndrome

Oxidative stress seems to be present in patients with polycystic ovary syndrome (PCOS). The aim of this study was to evaluate the correlation between characteristics of PCOS and serum concentrations of afamin, a novel binding protein for the antioxidant vitamin E. A total of 85 patients with PCOS and 76 control subjects were investigated in a pilot cross-sectional study design between 2009 and 2013 in the University Hospital of Essen, Germany. Patients with PCOS were diagnosed according to the Rotterdam ESHRE/ASRM-sponsored PCOS Consensus Workshop Group. Afamin and diagnostic parameters of PCOS were determined at early follicular phase. Afamin concentrations were significantly higher in patients with PCOS than in controls (odds ratio (OR) for a 10 mg/ml increase in afamin=1.3, 95% CI=1.08–1.58). This difference vanished in a model adjusting for age, BMI, free testosterone index (FTI), and sex hormone-binding globulin (SHBG) (OR=1.05, 95% CI=0.80–1.38). In patients with PCOS, afamin correlated significantly with homeostatic model assessment-insulin resistance (HOMA-IR), fasting glucose, BMI, FTI, and SHBG (P<0.001), but in a multivariate linear model, only HOMA-IR remained significantly associated with afamin (P=0.001). No correlation was observed between afamin and androgens, LH, FSH, LH/FSH ratio, antral follicle count, ovarian volume, or anti-Müllerian hormone. In conclusion, elevated afamin values may indicate a state of oxidative stress and inflammation, strongly associated with IR and offering an indicator of impaired glucose tolerance in patients with PCOS irrespective of obesity.

Imatinib – eine mögliche Therapieoption beim Zervixkarzinom: Ergebnisse einer präklinischen Phase-I-Studie

BACKGROUND In the last few years, the therapy of cervical carcinoma has progressed substantially due to the use of simultaneous platinum- containing radiochemotherapy. However, there are no data which evaluate an individualized treatment adapted to tumor biology, in spite of the fact that patients show remarkably different responses to chemotherapy. Therefore this preclinical phase I study aims at finding therapeutic alternatives to the current cytostatic drugs to treat cervical carcinoma. MATERIAL AND METHODS In a tumor chemosensitivity assay, 8 drugs were tested on freshly isolated tumor cells of 16 patients [carbo- and cisplatin, topotecan, paclitaxel as well as the 2 tyrosine kinase inhibitors imatinib (Glivec) and gefitinib (Iressa (R) ) and the 2 monoclonal antibodies cetuximab (Erbitux) and trastuzumab (Herceptin (R) )]. RESULTS Overall the test was evaluable for 16 specimens (100%). Ten of 15 tumor samples (66.6%) were sensitive to imatinib. A sensitive therapeutic response could be demonstrated in all tested FIGO stages. An interindividual comparison could establish sensitivity to cetuximab in 12.5% of cases, to gefitinib in 6.25%, to trastuzumab in 6.6%, to cisplatin in 13.3%, to carboplatin in 7.6%, to paclitaxel in 93.8% and to topotecan in 25%. CONCLUSION Imatinib seems to be an efficacious therapeutic option for patients with cervical carcinoma, independently of tumor subtype.BACKGROUND: In the last few years, the therapy of cervical carcinoma has progressed substantially due to the use of simultaneous platinum- containing radiochemotherapy. However, there are no data which evaluate an individualized treatment adapted to tumor biology, in spite of the fact that patients show remarkably different responses to chemotherapy. Therefore this preclinical phase I study aims at finding therapeutic alternatives to the current cytostatic drugs to treat cervical carcinoma. MATERIAL AND METHODS: In a tumor chemosensitivity assay, 8 drugs were tested on freshly isolated tumor cells of 16 patients [carbo- and cisplatin, topotecan, paclitaxel as well as the 2 tyrosine kinase inhibitors imatinib (Glivec) and gefitinib (Iressa (R) ) and the 2 monoclonal antibodies cetuximab (Erbitux) and trastuzumab (Herceptin (R) )]. RESULTS: Overall the test was evaluable for 16 specimens (100%). Ten of 15 tumor samples (66.6%) were sensitive to imatinib. A sensitive therapeutic response could be demonstrated in all tested FIGO stages. An interindividual comparison could establish sensitivity to cetuximab in 12.5% of cases, to gefitinib in 6.25%, to trastuzumab in 6.6%, to cisplatin in 13.3%, to carboplatin in 7.6%, to paclitaxel in 93.8% and to topotecan in 25%. CONCLUSION: Imatinib seems to be an efficacious therapeutic option for patients with cervical carcinoma, independently of tumor subtype.

Impact of maternal serum levels of Visfatin, AFP, PAPP-A, sFlt-1 and PlGF at 11–13 weeks gestation on small for gestational age births

Abstract Objective: Investigating potential value of maternal serum Visfatin, sFlt-1, PlGF, AFP, PAPP-A levels at first trimester for prediction of small for gestational age (SGA) at birth. Methods: Measurements were performed in 20 SGA and 65 control cases. Logistic regression analysis adjusted for age and weeks of pregnancy at data collection was performed to estimate odds ratios (OR), 95% confidence intervals (95% CI) and p values separately for each potential predictor. A multiple regression model was used to assess the impact of all the promising predictors adjusted for each other. Receiver operating characteristic (ROC) analysis was used to indicate the ability to discriminate between SGA cases and controls. Results: There was an association of serum PlGF levels (OR 0.53 per interquartile range [IQR] increase in PlGF; 95% CI 0.24–1.16), sFlt-1/PlGF ratio (OR 1.42 per IQR increase in sFlt-1/PlGF; 95% CI 1.03–1.96), serum Visfatin levels (OR 0.31 per IQR increase in Visfatin; 95% CI 0.10–0.95) and smoking (OR 4.24; 95% CI 1.10–16.37) with SGA at birth. Conclusions: Associations between SGA and lower PlGF, Visfatin levels as well as increased sFlt-1/PlGF ratio and smoking status were detected which may contribute to predict SGA.

Changes in the Blood Serum Levels of the Costimulatory Soluble B7-H4 Molecule in Pregnant Women During the Peripartal Phase.

B7‐H4, a transmembrane protein that negatively regulates T lymphocytes, seems to play a role in the suppression of the im\mune response at the maternal–fetal interface. The aim of this study was to compare the blood serum concentration levels of soluble B7‐H4 (sB7‐H4) prepartal and postpartal in both women who experienced spontaneous onset of labor and those who underwent elective cesarian section.

The Use of Plasma Exchange in a Very Early-onset and Life Threatening, Hemolysis, Elevated Liver Enzymes, and Low Platelet (HELLP) Syndrome: A Case Report

Background: HELLP syndrome is a life threatening pregnancy and early postpartum complication. Very early presentation (before the 21st pregnancy week) is rare and represents an extremely difficult situation for patients and physicians. Supportive therapy (magnesium sulfate, antihypertensive drugs and corticosteroids) may be useful to prolong pregnancy; till now the removing of placenta is the only effective therapeutic option. Plasmapheresis may represent a new and efficacious therapeutic option. Case description: The article reports on a case of very-early onset HELLP Syndrome at the 18th (17+5) week of gestation. It was a challenging clinical and therapeutic case. Since the fetus did not show any signs of growth retardation or pathological Doppler findings, indicating a good fetal prognosis, we used plasmapheresis as an ultima ratio to prolong pregnancy. With plasmapheresis, the pregnancy was prolonged for 20 days. Unfortunately the deterioration of the clinical situation required delivery in the 21st (20+4) gestational week. Conclusion: Plasmapheresis allows prolongation of pregnancy with early onset, life threatening HELLPSyndrome.

Oxygen Sensitivity of Placental Trophoblast Connexins 43 and 46: A Role in Preeclampsia?

Several gap junction connexins have been shown to be essential for appropriate placental development and function. It is known that the expression and distribution of connexins change in response to environmental oxygen levels. The placenta develops under various oxygen levels, beginning at a low oxygen tension of approximately 2% and increasing to a tension of 8% after the onset of the uteroplacental circulation. Moreover, it has been shown that during preeclampsia (PE) placentas are subjected to chronic hypoxia. Therefore, we investigated oxygen sensitivity of placental connexins 43 and 46. Using the trophoblast cell line Jar, we demonstrated that the expression of connexin43 increased during acute hypoxia but decreased during chronic hypoxia. Chronic hypoxia resulted in the translocation of connexin43 from the membrane to the cytoplasm and in a reduction in its communication properties. In contrast, the expression of connexin46 was down‐regulated during chronic hypoxia and was translocated from perinuclear areas to the cell membrane. Hypoxia‐inducible factor (HIF) knockdown showed that the translocation of connexin43 but not that of connexin46 was HIF‐2α dependent and was mediated by phosphoinositide 3‐kinase. The up‐regulation of connexin43 in combination with the down‐regulation of connexin46 was confirmed in placental explants cultivated under low oxygen and in placentas with early‐onset PE. Taken together, in Jar cells, placental connexins 43 and 46 are regulated during periods of low oxygen in opposite manners. The oxygen sensing of connexins in the trophoblast may play a role in physiological and pathophysiological oxygen conditions and thus may contribute to PE. J. Cell. Biochem. 116: 2924–2937, 2015.

Follistatin during pregnancy and its potential role as an ovarian suppressing agent

OBJECTIVE Ovarian quiescence is a common condition during pregnancy. In vitro, follistatin, an antagonist of follicle-stimulating hormone, blocks follicular development at early stages, and its serum levels increase during pregnancy. A possible surrogate biomarker of ovarian arrest during pregnancy is a decrease in anti-mullerian hormone (AMH) levels followed by an increase in these levels on the second day after labor. The purpose of this study was to determine whether follistatin could act as an ovarian-suppressing agent during pregnancy. Follistatin levels and AMH levels were determined at various stages of pregnancy and postpartum. STUDY DESIGN The follistatin and AMH levels of 69 patients were retrospectively determined with the AMH Gen II ELISA and with the Human Follistatin Quantikine ELISA Kit. For 49 patients, samples were available from various trimesters for cross-sectional analysis; for the other 20, samples were available longitudinally from day one before labor and then daily on days 1 through 4 after labor. Statistical significance was determined with linear regression, the Friedman rank sum test and the Wilcoxon-Nemenyi-McDonald-Thompson post hoc test. RESULTS The behavior of follistatin levels was exactly opposite that of AMH levels: Follistatin levels increased significantly during pregnancy and on the first day after parturition but declined afterwards, whereas AMH levels decreased significantly during pregnancy and increased after labor. CONCLUSION Follistatin can induce ovarian arrest during pregnancy.

Serum concentrations of soluble B7-H4 in early pregnancy are elevated in women with preterm premature rupture of fetal membranes

To determine the association between maternal soluble B7‐H4 (sB7‐H4) and the preterm premature rupture of the amniotic membranes (pPROM), the blood serum concentration levels of sB7‐H4 were studied.