Esther Guetta

Sheba Medical Center · Danek Gertner Instittue of Human Genetics

Research interests

  • Interests
    Human Genetics, Medical Genetics, Genetic Analysis, Genetic Counseling, Gene Expression, Microarray

Publications

  • 5.23
    Impact points
    Automatic retrieval of single microchimeric cells and verification of identity by on-chip multiplex PCR.

    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 diagnosis since it is both imperative and difficult to avoid contaminating the minority of fetal cells with mate... [more] 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 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.
  • Rapid detection of fetal Mendelian disorders: Tay-Sachs disease.

    Esther Guetta, Leah Peleg

    Methods in molecular biology (Clifton, N.J.). 02/2008; 444:147-59.

    Tay-Sachs disease is an autosomal recessive storage disease caused by the impaired activity of the lysosomal enzyme hexosaminidase A. In this fatal disease, the sphingolipid GM2 ganglioside accumulates in the neurons. Due to high carrier rates and the severity of the disease, population screening an... [more] Tay-Sachs disease is an autosomal recessive storage disease caused by the impaired activity of the lysosomal enzyme hexosaminidase A. In this fatal disease, the sphingolipid GM2 ganglioside accumulates in the neurons. Due to high carrier rates and the severity of the disease, population screening and prenatal diagnosis of Tay-Sachs disease are routinely carried out in Israel. Laboratory diagnosis of Tay-Sachs is carried out with biochemical and DNA-based methods in peripheral and umbilical cord blood, amniotic fluid, and chorionic villi samples. The assay of hexosaminidase A (Hex A) activity is carried out with synthetic substrates, 4-methylumbelliferyl-6-sulfo-N-acetyl-beta-glucosaminide (4-MUGS) and 4-methylumbelliferil-N-acetyl-beta-glucosamine (4-MUG), and the DNA-based analysis involves testing for the presence of specific known mutations in the alpha-subunit gene of Hex A. Prenatal diagnosis of Tay-Sachs disease is accomplished within 24-48 h from sampling. The preferred strategy is to simultaneously carry out enzymatic analysis in the amniotic fluid supernatant or in chorionic villi and molecular DNA-based testing in an amniotic fluid cell-pellet or in chorionic villi.
  • 5.39
    Impact points
    Human embryonic stem cell transplantation to repair the infarcted myocardium.

    Jonathan Leor, Sharon Gerecht, Smadar Cohen, Liron Miller, Radka Holbova, Anna Ziskind, Michal Shachar, Micha S Feinberg, Esther Guetta, Joseph Itskovitz-Eldor

    Heart (British Cardiac Society). 10/2007; 93(10):1278-84.

    OBJECTIVE: To test the hypothesis that human embryonic stem cells (hESCs) can be guided to form new myocardium by transplantation into the normal or infarcted heart, and to assess the influence of hESC-derived cardiomyocytes (hESCMs) on cardiac function in a rat model of myocardial infarction (MI). ... [more] OBJECTIVE: To test the hypothesis that human embryonic stem cells (hESCs) can be guided to form new myocardium by transplantation into the normal or infarcted heart, and to assess the influence of hESC-derived cardiomyocytes (hESCMs) on cardiac function in a rat model of myocardial infarction (MI). METHODS: Undifferentiated hESCs (0.5-1x10(6)), human embryoid bodies (hEBs) (4-8 days; 0.5-1x10(6)), 0.1 mm pieces of embryonic stem-derived beating myocardial tissue, and phosphate-buffered saline (control) were injected into the normal or infarcted myocardium of athymic nude rats (n = 58) by direct injection into the muscle or into preimplanted three-dimensional alginate scaffold. By 2-4 weeks after transplantation, heart sections were examined to detect the human cells and differentiation with fluorescent in situ hybridisation, using DNA probes specific for human sex chromosomes and HLA-DR or HLA-ABC immunostaining. RESULTS: Microscopic examination showed transplanted human cells in the normal, and to a lesser extent in the infarcted myocardium (7/7 vs 2/6; p<0.05). The transplanted hESCs and hEBs rarely created new vessels and did not form new myocardium. Transplantation of hESCM tissue into normal heart produced islands of disorganised myofibres, fibrosis and, in a single case, a teratoma. However, transplantation of hESCMs into the infarcted myocardium did prevent post-MI dysfunction and scar thinning. CONCLUSIONS: Undifferentiated hESCs and hEBs are not directed to form new myocardium after transplantation into normal or infarcted heart and may create teratoma. Nevertheless, this study shows that hESC-derived cardiomyocyte transplantation can attenuate post-MI scar thinning and left ventricular dysfunction.
  • 2.38
    Impact points
    Is sperm donor karyotype analysis necessary?

    Ruth Weissenberg, Talia Litmanovitz, Michal Dekel, Ayala Aviram-Goldring, Igael Madgar, Michal Berkenstadt, Esther Guetta

    Reproductive biomedicine online. 07/2007; 14(6):724-6.

    A case study involving four female patients inseminated with sperm samples from the same donor is reported. Routine amniocentesis of one of the patients revealed that the fetus is a carrier of a balanced reciprocal translocation, 46,XY,t(1;10)(q12;q11.2), which was subsequently detected in the donor... [more] A case study involving four female patients inseminated with sperm samples from the same donor is reported. Routine amniocentesis of one of the patients revealed that the fetus is a carrier of a balanced reciprocal translocation, 46,XY,t(1;10)(q12;q11.2), which was subsequently detected in the donor. Counselled amniocentesis in the three remaining patients led to the detection of an additional translocation carrier fetus. All four pregnancies resulted in live births. Fluorescence in-situ hybridization was applied to identify normal, balanced or imbalanced sperm cells of the donor. Accordingly, routine karyotype analysis of sperm donors was introduced, and is now recommended in the authors' unit.
  • 1.71
    Impact points
    Noninvasive detection of fetal sex: the laboratory diagnostician's view.

    Esther Guetta

    Prenatal diagnosis. 08/2006; 26(7):635-6.

    Toward the end of the twentieth century it was discovered that cell-free fetal DNA sequences could be detected in maternal blood plasma. Initially, Y-chromosome sequences originating from male fetuses were targeted in cell-free DNA extracted from maternal plasma in order to demonstrate proof of this... [more] Toward the end of the twentieth century it was discovered that cell-free fetal DNA sequences could be detected in maternal blood plasma. Initially, Y-chromosome sequences originating from male fetuses were targeted in cell-free DNA extracted from maternal plasma in order to demonstrate proof of this concept towards the development of noninvasive prenatal diagnosis methods. Clinical application of this approach is now possible. Fetal sex can be detected through a procedure that is noninvasive with respect to the fetus. Specifically, the presence of Y-chromosome sequences in maternal blood plasma indicates that the fetus is male, whereas lack of a signal will indicate that the fetus is female. Fetal sex can be detected very early, from at least the 7th week of pregnancy (and even earlier, according to several studies), about two months before this information is available through ultrasound scanning.Although the controversial issue of fetal sexing is not new, it is expected that with the availability of an accurate noninvasive test, public interest will rise. It is therefore imperative that an authorized committee of experts in each country generates an official policy regarding application of the test.
  • 7.75
    Impact points
    Human umbilical cord blood-derived CD133+ cells enhance function and repair of the infarcted myocardium.

    Jonathan Leor, Esther Guetta, Micha S Feinberg, Hanan Galski, Iris Bar, Radka Holbova, Liron Miller, Parvin Zarin, David Castel, Israel M Barbash, Arnon Nagler

    Stem cells (Dayton, Ohio). 04/2006; 24(3):772-80.

    The use of adult stem cells for myocardial tissue repair might be limited in elderly and sick people because their cells are depleted and exhausted. The present study was conducted to explore the potential of human umbilical cord blood (UCB) CD133+ progenitor cells for myocardial tissue repair in a ... [more] The use of adult stem cells for myocardial tissue repair might be limited in elderly and sick people because their cells are depleted and exhausted. The present study was conducted to explore the potential of human umbilical cord blood (UCB) CD133+ progenitor cells for myocardial tissue repair in a model of extensive myocardial infarction (MI). CD133+ progenitor cells were isolated from newborn UCB. Cells (1.2-2 x 10(6)) or saline (control) was infused intravenously 7 days after permanent coronary artery ligation in athymic nude rats. Left ventricular (LV) function was assessed before and 1 month after infusion by echocardiography. Tracking of human cells was performed by fluorescent in situ hybridization for human X and Y chromosomes or by immunostaining for HLA-DR or HLA-ABC. One month after delivery, LV fractional shortening improved by 42 +/- 17% in cell-treated hearts and decreased by 39 +/- 10% in controls (p = .001). Anterior wall thickness decreased significantly in controls but not in treated hearts. Microscopic examination revealed that the UCB cells were able to migrate, colonize, and survive in the infarcted myocardium. Human cells were identified near vessel walls and LV cavity and were occasionally incorporated into endothelial cells in six of nine cell-treated animals but not in controls. Scar tissue from cell-treated animals was significantly populated with autologous myofibroblasts as indicated by colocalization of HLA-DR and alpha-smooth muscle actin staining. In conclusion, the present work suggests that, after MI, intravenous delivery of human UCB-derived CD133+ cells can produce functional recovery by preventing scar thinning and LV systolic dilatation.
  • 3.97
    Impact points
    Embryonic karyotype in recurrent miscarriage with parental karyotypic aberrations.

    Howard Carp, Esther Guetta, Haya Dorf, David Soriano, Gad Barkai, Eyal Schiff

    Fertility and sterility. 03/2006; 85(2):446-50.

    OBJECTIVE: To assesses chromosomal aberrations in the abortus in recurrent miscarriage, in the presence of parental chromosomal aberrations. DESIGN: Retrospective comparative cohort study. SETTING: Tertiary referral unit in university hospital. PATIENT(S): One thousand one hundred eight patients wit... [more] OBJECTIVE: To assesses chromosomal aberrations in the abortus in recurrent miscarriage, in the presence of parental chromosomal aberrations. DESIGN: Retrospective comparative cohort study. SETTING: Tertiary referral unit in university hospital. PATIENT(S): One thousand one hundred eight patients with 3-16 miscarriages before 20 weeks gestation; 113 patients with and 995 without chromosomal aberrations. INTERVENTION(S): Karyotyping by standard G-banding techniques of both parents, and of 205 abortuses collected at curettage. MAIN OUTCOME MEASURE(S): The incidence of the euploidic and aneuploidic abortuses according to the parental karyotype. RESULT(S): Two hundred three abortuses were successfully karyotyped. In 164 embryos of patients with no parental chromosomal aberrations, 23.2% (38/164) had chromosome aberrations. Of the 39 abortuses karyotyped in patients with chromosomal aberrations, 17 had normal karyotypes, 8 had balanced translocations, 2 had inversions identical to the parents, and 12 (30.8%) had abnormal karyotypes. This difference is not statistically significant (odd ratio 1.47, 95% confidence interval 0.63-3.39). Only 4 of the 39 karyotyped abortuses had an unbalanced translocation. CONCLUSION(S): Parental karyotyping was not particularly predictive of a subsequent miscarriage as a result of chromosomal aberrations as 43.5% of abortuses were euploidic, and the parental aberration was only passed on to the abortus in 10% of cases.
  • 3.28
    Impact points
    Chromosomal abnormalities and birth defects among couples with colchicine treated familial Mediterranean fever.

    Michal Berkenstadt, Boaz Weisz, Howard Cuckle, Michal Di-Castro, Esther Guetta, Gad Barkai

    American journal of obstetrics and gynecology. 11/2005; 193(4):1513-6.

    OBJECTIVE: To determine whether colchicine prescribed for familial Mediterranean fever is teratogenic. STUDY DESIGN: Reproductive histories were analyzed from 326 couples referred for prenatal diagnosis because 1 partner was affected. Numbers of chromosomal abnormalities and birth defects were compa... [more] OBJECTIVE: To determine whether colchicine prescribed for familial Mediterranean fever is teratogenic. STUDY DESIGN: Reproductive histories were analyzed from 326 couples referred for prenatal diagnosis because 1 partner was affected. Numbers of chromosomal abnormalities and birth defects were compared with numbers expected from published rates. RESULTS: There were 901 pregnancies, and amniocentesis had been performed in 566, all but 3 conceived while taking colchicine. Seven numerical chromosomal abnormalities were found, not statistically significantly greater than the 4.99 expected from maternal age and gestation of diagnosis (P = .24): unbalanced structural abnormalities were 6, compared with 3.22 expected (P = .11). There were 7 birth defects, a considerably lower rate than reported in local malformation registers. CONCLUSION: The current policy of routine amniocentesis in pregnancies of couples taking colchicine should not be changed until sufficient data accumulates to establish whether the higher number of chromosomal anomalies in this group is significant.
  • 2.37
    Impact points
    Trophoblasts isolated from the maternal circulation: in vitro expansion and potential application in non-invasive prenatal diagnosis.

    Esther Guetta, Liat Gutstein-Abo, Gad Barkai

    The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society. 04/2005; 53(3):337-9.

    Prenatal diagnosis based on rare fetal cells in maternal blood is currently not a feasible option. An effort was made to improve cell yields by targeting trophoblast cells. After sorting, the HLA-G-positive cell fraction was analyzed directly or after culture. In situ hybridization technology was ap... [more] Prenatal diagnosis based on rare fetal cells in maternal blood is currently not a feasible option. An effort was made to improve cell yields by targeting trophoblast cells. After sorting, the HLA-G-positive cell fraction was analyzed directly or after culture. In situ hybridization technology was applied to prove fetal cell source in samples from women carrying a male fetus and to predict gender in samples without previous knowledge of fetal sex. In vitro culture led to a significant increase in fetal cells and accurate gender prediction in 93% of these samples. This approach might be useful for non-invasive prenatal diagnosis.
  • 2.20
    Impact points
    Human umbilical cord blood cells: a new alternative for myocardial repair?

    J Leor, E Guetta, P Chouraqui, V Guetta, A Nagler

    Cytotherapy. 02/2005; 7(3):251-7.

    Cell therapy for myocardial disease is a rapidly progressive field. However, present strategies of cell transplantation into the infarcted myocardium have limitations from practical points of view. One of the biggest challenges is to achieve a sufficient number of suitable cells. Umbilical cord bloo... [more] Cell therapy for myocardial disease is a rapidly progressive field. However, present strategies of cell transplantation into the infarcted myocardium have limitations from practical points of view. One of the biggest challenges is to achieve a sufficient number of suitable cells. Umbilical cord blood (UCB), an unlimited source of stem/progenitor cells that could be used for transplantation into the injured heart, is readily available. The aim of our review is to describe the potential and prospect of UCB as a new supplier of cells for myocardial repair. The use of UCB stem cells might be of importance to elderly and sick people in whom the availability of autologous stem cells is limited.
  • 4.15
    Impact points
    Analysis of fetal blood cells in the maternal circulation: challenges, ongoing efforts, and potential solutions.

    Esther Guetta, Michal J Simchen, Keren Mammon-Daviko, Daphna Gordon, Ayala Aviram-Goldring, Nurit Rauchbach, Gad Barkai

    Stem cells and development. 03/2004; 13(1):93-9.

    The invasive procedures amniocentesis and chorionic villus sampling (CVS) are routinely applied in pregnancies at risk for fetal abnormalities and the results obtained are the gold standard for prenatal diagnosis. Because these methods of fetal cell procurement involve a 0.5-2% risk for fetal loss, ... [more] The invasive procedures amniocentesis and chorionic villus sampling (CVS) are routinely applied in pregnancies at risk for fetal abnormalities and the results obtained are the gold standard for prenatal diagnosis. Because these methods of fetal cell procurement involve a 0.5-2% risk for fetal loss, they are recommended mainly in cases at high risk for fetal genetic or cytogenetic abnormalities. The development of a reproducible, reliable, noninvasive method based on retrieval of rare fetal cells from the maternal circulation will render testing feasible for the general population. Despite intensive investigation, a satisfactory, clinically acceptable method has not yet emerged. Several cell types have been targeted to this end, mostly nucleated red blood cells (NRBC), CD34+ hematopoietic progenitors, and trophoblasts. Although these cell types have been unequivocally proven to be present in the maternal circulation, each bears a significant disadvantage, rendering their application in clinical testing currently impossible: NRBC cannot be expanded in culture, thereby ruling out metaphase chromosome analysis, an essential component of prenatal diagnosis. CD34+ cells do posses the potential for in vitro proliferation, however, they have been found to persist in the maternal circulation after delivery, thereby complicating diagnosis in consecutive pregnancies. Trophoblasts are not consistently detected in the maternal circulation. Moreover, due to the lack of a definitive fetal cell marker and a reliable sorting method, foolproof fetal cell identification of any of these cell types is not possible. This report outlines the obstacles that impede development of a method for noninvasive fetal cell sampling for prenatal genetic diagnosis, along with a description of our efforts to analyze simultaneously two fetal blood cell types, NRBC and CD34+ cells in maternal blood during pregnancy, and the problems encountered. This work and that of others lead us to suggest potential future directions to help develop this important technique.
  • 14.82
    Impact points
    Systemic delivery of bone marrow-derived mesenchymal stem cells to the infarcted myocardium: feasibility, cell migration, and body distribution.

    Israel M Barbash, Pierre Chouraqui, Jack Baron, Micha S Feinberg, Sharon Etzion, Ariel Tessone, Liron Miller, Esther Guetta, Dov Zipori, Laurence H Kedes, Robert A Kloner, Jonathan Leor

    Circulation. 09/2003; 108(7):863-8.

    BACKGROUND: Systemic delivery of bone marrow-derived mesenchymal stem cells (BM-MSCs) is an attractive approach for myocardial repair. We aimed to test this strategy in a rat model after myocardial infarction (MI). METHODS AND RESULTS: BM-MSCs were obtained from rat bone marrow, expanded in vitro to... [more] BACKGROUND: Systemic delivery of bone marrow-derived mesenchymal stem cells (BM-MSCs) is an attractive approach for myocardial repair. We aimed to test this strategy in a rat model after myocardial infarction (MI). METHODS AND RESULTS: BM-MSCs were obtained from rat bone marrow, expanded in vitro to a purity of >50%, and labeled with 99mTc exametazime, fluorescent dye, LacZ marker gene, or bromodeoxyuridine. Rats were subjected to MI by transient coronary artery occlusion or to sham MI. 99mTc-labeled cells (4x10(6)) were transfused into the left ventricular cavity of MI rats either at 2 or 10 to 14 days after MI and were compared with sham-MI rats or MI rats treated with intravenous infusion. Gamma camera imaging and isolated organ counting 4 hours after intravenous infusion revealed uptake of the 99mTc-labeled cells mainly in the lungs, with significantly smaller amounts in the liver, heart, and spleen. Delivery by left ventricular cavity infusion resulted in drastically lower lung uptake, better uptake in the heart, and specifically higher uptake in infarcted compared with sham-MI hearts. Histological examination at 1 week after infusion identified labeled cells either in the infarcted or border zone but not in remote viable myocardium or sham-MI hearts. Labeled cells were also identified in the lung, liver, spleen, and bone marrow. CONCLUSIONS: Systemic intravenous delivery of BM-MSCs to rats after MI, although feasible, is limited by entrapment of the donor cells in the lungs. Direct left ventricular cavity infusion enhances migration and colonization of the cells preferentially to the ischemic myocardium.
  • 14.82
    Impact points
    Cellular cardiomyoplasty of cardiac fibroblasts by adenoviral delivery of MyoD ex vivo: an unlimited source of cells for myocardial repair.

    Sharon Etzion, Israel M Barbash, Micha S Feinberg, Parvin Zarin, Liron Miller, Esther Guetta, Radka Holbova, Robert A Kloner, Laurence H Kedes, Jonathan Leor

    Circulation. 10/2002; 106(12 Suppl 1):I125-30.

    BACKGROUND: The muscle-specific MyoD family of transcription factors function as master genes that are able to prompt myogenesis in a variety of cells. The purpose of our study was to determine whether MyoD could induce primary cardiac fibroblasts, isolated from infarcted myocardium or pericardium, ... [more] BACKGROUND: The muscle-specific MyoD family of transcription factors function as master genes that are able to prompt myogenesis in a variety of cells. The purpose of our study was to determine whether MyoD could induce primary cardiac fibroblasts, isolated from infarcted myocardium or pericardium, to undergo myogenic conversion in a clinically relevant approach. METHODS AND RESULTS: Primary rat fibroblasts from 7-day-old infarcted myocardium or normal pericardium were transfected by an E1/E3-deleted adenoviral vector carrying both a human MyoD cDNA driven by a CMV promoter and a green fluorescent protein (GFP) reporter gene driven by a second CMV promoter. Expression of MyoD caused myogenic differentiation of cultured fibroblasts, as defined by elongation and fusion into multinucleated myotubes, typical cross striation as identified by electron microscopy, and positive immunostaining for sarcomeric actin, fast myosin heavy chain (MHC), and actinin. The myogenic cells (1.5x10(6)) were transplanted into the infarcted myocardium 7 days after coronary artery occlusion. By 1 month after transplantation, the converted fibroblasts gave rise to a cluster of myogenic cells that in a few hearts occupied a large part of the scar with positive immunostaining for the myogenic proteins fast-MHC and sarcomeric actin. A few cells expressed the gap junction protein connexin 43 in a disorganized manner. There was no positive staining in the control hearts treated with injections of untreated fibroblasts or culture medium. CONCLUSIONS: Our work shows that it is possible to exploit the unique capacity of MyoD to activate myogenesis in fibroblasts ex vivo and to create a vast source of autologous myogenic cells for transplantation.
  • 5.80
    Impact points
    Effect of cytomegalovirus immediate early gene products on endothelial cell gene activity.

    E Guetta, E M Scarpati, P E DiCorleto

    Cardiovascular research. 07/2001; 50(3):538-46.

    OBJECTIVE: Cytomegalovirus (CMV) infection or reactivation from latency in vascular cells have been shown to contribute to atherosclerosis. CMV-infected endothelial cells (ECs) exhibit enhanced adhesion and procoagulant properties, changes compatible with processes observed in atherogenesis. The maj... [more] OBJECTIVE: Cytomegalovirus (CMV) infection or reactivation from latency in vascular cells have been shown to contribute to atherosclerosis. CMV-infected endothelial cells (ECs) exhibit enhanced adhesion and procoagulant properties, changes compatible with processes observed in atherogenesis. The major immediate early promoter drives immediate early gene transcription. Immediate early (IE) gene products, IE72 and IE84, function as transcription factors and thereby influence expression of cellular genes, in permissive cells as well as in abortive infections, in which viral activity is limited to immediate early expression. ECs have been shown to harbor latent CMV, support abortive CMV infection and, under certain conditions, are permissive to productive viral infection. The objective of this study was to determine whether immediate early expression alone (in the absence of further progression of the virus life-cycle) results in the activation of EC genes associated with atherogenesis. METHODS: The study was conducted in an in vitro transient transfection system in human and bovine vascular ECs, with CMV immediate early gene expression vectors and plasmids containing promoter sequences of adhesion molecule, growth factor and viral promoters driving the transcription of reporter genes. RESULTS: CMV immediate early gene expression resulted in an increase in monocyte adhesion to ECs and in the relative promoter activities of cellular growth factor and adhesion molecule genes. In addition, the viral major immediate early promoter was regulated in EC by thrombin and the immediate early gene products. CONCLUSION: These results infer the possible existence of a positive feedback mechanism in the developing atherosclerotic lesion, in which enhanced immediate early gene expression leads to subsequent activation of EC genes, which might in turn result in further activation of CMV activity.
  • 14.82
    Impact points
    Cytomegalovirus infection of rats increases the neointimal response to vascular injury without consistent evidence of direct infection of the vascular wall.

    Y F Zhou, M Shou, E Guetta, R Guzman, E F Unger, Z X Yu, J Zhang, T Finkel, S E Epstein

    Circulation. 11/1999; 100(14):1569-75.

    BACKGROUND: Previous studies suggest that infection may play a role in restenosis and atherogenesis; cytomegalovirus (CMV) is one of the implicated pathogens. To determine a potential causal role of CMV in these disease processes, we assessed whether CMV infection increases the neointimal response t... [more] BACKGROUND: Previous studies suggest that infection may play a role in restenosis and atherogenesis; cytomegalovirus (CMV) is one of the implicated pathogens. To determine a potential causal role of CMV in these disease processes, we assessed whether CMV infection increases the neointimal response to injury of the rat carotid artery. METHODS AND RESULTS: Carotid injury was performed on 60 rats; immediately thereafter, 30 rats were infected with rat CMV, and the other 30 were mock-infected. Six weeks later, rats were euthanized, and the salivary glands, spleen, and carotid arteries were harvested. CMV infection was associated with significant exacerbation of the neointimal response to injury (neointimal to medial ratio 0.81+/-0. 59 versus 0.31+/-0.38 in CMV-infected versus control rats; P<0.0001). This occurred despite absence of infectious virus from vascular tissues and detection of CMV DNA by polymerase chain reaction in the injured artery only at day 3 after infection. Persistent distant infection, associated with systemic cytokine response, was evidenced by isolation of infectious virus from homogenates of both salivary glands and spleen and by higher serum levels of interleukin (IL)-2 and IL-4 (but not interferon-gamma and tumor necrosis factor-alpha) in infected versus noninfected rats. CONCLUSIONS: CMV infection of immunocompetent adult rats increases the neointimal response to vascular injury, suggesting that CMV may play a causal role in atherosclerosis/restenosis. Importantly, this CMV-induced response occurs even without the presence of virus in the vascular wall, suggesting that inflammatory and immune responses to infection of nonvascular tissues may contribute to the vascular response to injury.
  • 9.21
    Impact points
    Monocytes harboring cytomegalovirus: interactions with endothelial cells, smooth muscle cells, and oxidized low-density lipoprotein. Possible mechanisms for activating virus delivered by monocytes to sites of vascular injury.

    E Guetta, V Guetta, T Shibutani, S E Epstein

    Circulation research. 08/1997; 81(1):8-16.

    Cytomegalovirus (CMV) infection and its periodic reactivation from latency may contribute to atherogenesis and restenosis. It is unknown how CMV is delivered to the vessel wall and is reactivated. We examined the following hypothesis: CMV, present in monocytes recruited to sites of vascular injury, ... [more] Cytomegalovirus (CMV) infection and its periodic reactivation from latency may contribute to atherogenesis and restenosis. It is unknown how CMV is delivered to the vessel wall and is reactivated. We examined the following hypothesis: CMV, present in monocytes recruited to sites of vascular injury, is activated by endothelial cell (EC) or smooth muscle cell (SMC) contact and by oxidized low-density lipoproteins (oxLDLs). The CMV major immediate-early promoter (MIEP) controls immediate-early (IE) gene expression, and thereby viral replication. To determine whether elements of the vessel wall can activate CMV present in monocytes, we transiently transfected the promonocytic cell line HL-60 with a chloramphenicol acetyltransferase reporter gene construct driven by MIEP. MIEP activity increased 1.7 +/- 0.5-fold (P = .02) when the transfected HL-60 cells were cocultured with ECs, 4.5 +/- 1.5-fold when cocultured with SMCs (P = .03), and 2.0 +/- 0.5-fold (P = .01) when exposed to oxLDL. The combination of oxLDL and EC coculture increased MIEP activity over 7-fold. We also found that freshly isolated human monocytes, infected with endothelium-passaged CMV, were capable of transmitting infectious virus to cocultured ECs or SMCs. CMV-related progression of atherosclerosis or restenosis may, at least in part, involve monocyte delivery of the virus to the site of vascular injury, where the vascular milieu, ie, contact with ECs, SMCs, and oxLDL, can contribute to viral reactivation and/or replication by enhancing CMV IE gene expression. The virus may then infect neighboring ECs or SMCs, initiating a cascade of events predisposing to the development of atherogenesis-related processes.
  • 15.39
    Impact points
    Human cytomegalovirus increases modified low density lipoprotein uptake and scavenger receptor mRNA expression in vascular smooth muscle cells.

    Y F Zhou, E Guetta, Z X Yu, T Finkel, S E Epstein

    The Journal of clinical investigation. 12/1996; 98(9):2129-38.

    Evidence suggests a possible role for human cytomegalovirus (HCMV) in the development of arteriosclerosis. One of the earliest events in plaque formation is the accumulation of lipid-laden foam cells, derived from macrophages and smooth muscle cells (SMCs). The lipid accumulation that occurs depends... [more] Evidence suggests a possible role for human cytomegalovirus (HCMV) in the development of arteriosclerosis. One of the earliest events in plaque formation is the accumulation of lipid-laden foam cells, derived from macrophages and smooth muscle cells (SMCs). The lipid accumulation that occurs depends upon the uptake of oxidized LDL (Ox-LDL), a process in which the scavenger receptor (SR) has been postulated to play an important role. We therefore examined the effects of HCMV on this process. We demonstrate that HCMV infection of human SMCs increases modified LDL uptake and stimulates class A SR gene (SR-A) mRNA expression. In addition, infection of rat SMCs with HCMV, which causes immediate early gene expression (IE72/IE84), but no early or late HCMV gene products and no cytopathic effects, also increases SMC uptake of Ox-LDL and acetylated LDL, with either effect blocked by an excess of either cold Ox-LDL or acetylated-LDL, and by fucoidin, an SR competitor. Cotransfection of an IE72, but not an IE84, expression plasmid and a plasmid containing a Class A SR promoter/reporter gene construct enhances SR promoter activity. Since increased Ox-LDL uptake is believed to play an important role in arteriosclerosis, these results provide a link between HCMV infection and arteriosclerotic plaque formation.
  • 30.76
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  • 14.82
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    Comparative effects of basic fibroblast growth factor and vascular endothelial growth factor on coronary collateral development and the arterial response to injury.

    D F Lazarous, M Shou, M Scheinowitz, E Hodge, V Thirumurti, A N Kitsiou, J A Stiber, A D Lobo, S Hunsberger, E Guetta, S E Epstein, E F Unger

    Circulation. 10/1996; 94(5):1074-82.

    BACKGROUND: We have shown that the angiogenic peptides basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) enhance canine coronary collateral development when administered for > or = 4 weeks. bFGF, a pluripotent mitogen of mesodermally derived cells, could theoreti... [more] BACKGROUND: We have shown that the angiogenic peptides basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) enhance canine coronary collateral development when administered for > or = 4 weeks. bFGF, a pluripotent mitogen of mesodermally derived cells, could theoretically exacerbate neointimal smooth muscle cell hyperplasia, a fundamental component of atherosclerosis. VEGF, an endothelial cell-specific mitogen and vascular permeability factor, could have deleterious effects related to vascular hyperpermeability. The present investigation had two aims: (1) to ascertain whether brief (7-day) systemic arterial treatment with bFGF or VEGF would improve myocardial collateral perfusion and (2) to determine whether these peptides induce neointimal accumulation in vivo. METHODS AND RESULTS: Dogs were subjected to ameroid-induced occlusion of the left circumflex coronary artery and randomized to bFGF 1.74 mg (n = 9), VEGF 0.72 mg (n = 9), or saline (n = 10) as a daily left atrial bolus (days 10 to 16). Additional dogs were randomized to VEGF 0.72 mg (n = 6) or saline (n = 5); however, treatment was delayed by 1 week. Coincident with the institution of treatment, all dogs underwent balloon denudation injury of the iliofemoral artery. bFGF markedly increased maximal collateral flow but did not exacerbate neointimal accumulation. VEGF had no discernible effect on maximal collateral flow, but it exacerbated neointimal thickening after vascular injury. CONCLUSIONS: Short-term treatment with bFGF enhanced collateral development without increasing neointimal accumulation at sites of vascular injury. Although VEGF did not increase collateral development as administered in this study, it significantly exacerbated neointimal accumulation. These data provide support for the clinical investigation of bFGF in selected patients with ischemic heart disease.
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    Selective killing of transformed rat cells by minute virus of mice does not require infectious virus production.

    E Guetta, M Mincberg, S Mousset, C Bertinchamps, J Rommelaere, J Tal

    Journal of virology. 02/1990; 64(1):458-62.

    Fischer rat fibroblasts, naturally resistant to killing by the fibrotropic strain of minute virus of mice [(parvovirus MVM(p)], became sensitive to MVM when transformed by polyomavirus. This sensitization did not involve an increase in the percentage of cells which synthesized viral capsid antigens ... [more] Fischer rat fibroblasts, naturally resistant to killing by the fibrotropic strain of minute virus of mice [(parvovirus MVM(p)], became sensitive to MVM when transformed by polyomavirus. This sensitization did not involve an increase in the percentage of cells which synthesized viral capsid antigens or in the percentage of cells which produced infectious virus. The addition of anti-MVM antiserum to the growth medium of MVM-infected cells had only a small effect on their survival rates, indicating that the majority of the killing effect of MVM occurs in a single cycle of infection. The data indicate that cell killing by MVM is independent of infectious virus production and thus support the notion that the preferential cytolytic effect is affected by viral cytotoxic gene products which accumulate to intolerable levels in transformed cells but not in normal ones. Finally, using cells transformed with polyomavirus and genomic and subgenomic clones of polyomavirus, we showed that the extent of sensitization to killing by MVM depended on the transforming agent used.

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