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L3. Trophoblast invasion and spiral artery transformation in pre-eclampsia and fetal growth restriction
Lectures / Pregnancy Hypertension: An International Journal of Women’s Cardiovascular Health 1 (2011) 238–272
promptly treated with acyclovir. Differential diagnosis may be difficult due to the overlap of several clinical and laboratory findings of these syndrome (Table 1). It is important that the clinician make the accurate diagnosis when possible because the management and complications from these syndromes may be different. For example, severe preeclampsia and AFLP are treated by delivery, whereas it is possible to continue pregnancy in those with TTP/HUS, and exacerbation of SLE. This review focuses on diagnosis, management, and counseling of women who develop these syndromes based on results of recent studies. doi:10.1016/j.preghy.2011.08.002
L2. Clinical utility of placental growth factor – Pathological insights from commercial assays Christopher Redman (University of Oxford, UK) Placental growth factor (PlGF) is a proangiogenic marker which has been identified as having potential clinical utility in the diagnosis and outcome prediction of women with hypertensive disorders of pregnancy. We consider here the available data and the insights that they bring to the potential management of these conditions. PlGF levels increase to week 32 and then decrease until term. In preeclampsia, there is increased release of its soluble receptor soluble fms-like tyrosine kinase-1 (sFlt1) from the placenta in response to oxidative and inflammatory stress, which binds to circulating vascular growth factors, including PlGF. As a consequence, circulating levels of noncomplexed PlGF are decreased in women with preeclampsia. There is consistent evidence of a strong correlation between altered levels of PlGF and sFlt-1 in pregnant women with preeclampsia [2]. Several immunoassays now exist to measure PlGF, with differing analytical specificity. We compared the new point-of-care immunoassay Triage PlGF (Alere) to an established research immunoassay, the Quantikine PlGF ELISA (R&D Systems). The median PlGF concentration measured on Triage PlGF, compared to the ELISA, was 4.5-fold lower for cases compared to only 1.5-fold lower in controls [1]. Benton et al. compared the performance of the immunoassays Triage PlGF and Elecsys sFlt-1/PlGF ratio (Roche). Both assays had optimal performance in diagnosing earlyonset preeclampsia with area under ROC curves of 0.99 (Triage 100% sensitivity, 96% specificity; Elecsys 64% sensitivity, 100% specificity for early-onset preeclampsia). The median PlGF concentration measured on Triage PlGF, compared to the Elecsys PlGF assay, was 5.2-fold lower for cases compared to only 1.6-fold lower in controls [3]. Stenczer measured PlGF concentration in HELLP syndrome, superimposed pre-eclampsia and pre-eclampsia, and from women with a final diagnosis of either chronic or new onset hypertension. Samples were collected from woman at diagnosis before 35 weeks GA. Low levels of PlGF at diagnosis were observed in 92% of women with proteinuric hypertension and 54% of women with non-proteinuric hypertension. Stenczer et al. [4] also studied time interval between blood draw and delivery in these women. PlGF was analysed
239
retrospectively and did not influence decision to deliver. Independent of diagnosis, PlGF concentration was associated with length of pregnancy after blood draw. PlGF concentration was significantly lower in women delivering preterm and lowest in women delivering before 35 weeks. The area under the ROC curve was 0.94 for the ability of PlGF to differentiate preterm from term delivery. In conclusion, PlGF increases throughout pregnancy to week 32, then decreases until term. The available assays differ in their specificity for the known isoforms and non-complexed PlGF, and this might explain the observed differences in discrimination of cases from controls between assays. At diagnosis before 35 weeks gestation, PlGF concentrations potentially predict length of pregnancy, indicating which women will deliver pre-term not only in pre-eclampsia, HELLP and superimposed pre-eclampsia, but also in nonproteinuric hypertension, causing us to re-consider how we assess risk in this latter group. Larger prospective studies are needed to confirm the potential of PlGF. References Redman C, Lodge T, Meacher H, Marks J, Simms C, Sargent I. Triage PLGF test: point-of-care assay of plasma placental growth factor to diagnose preeclampsia. Adv Perinat Med 2010. Levine RJ, Maynard SE, Qian C, et al. Circulating angiogenic factors and the risk of preeclampsia. N Engl J Med ];350:672–83. Benton SJ, Hu Y, Xie F, Kupfer K, Lee SW, Magee LA, von Dadelszen P. Angiogenic factors as diagnostic tests for pre-eclampsia: a performance comparison between two commercial immunoassays. Am J Obstet Gynecol 2011. doi:10.1016/j.ajog.2011.06.058. Stenczer B, et al. Evaluation of a new simple and rapid placental growth factor test for the evaluation of hypertensive disorders of pregnancy. International Federation of Placenta Associations, 2011 (accepted abstract). doi:10.1016/j.preghy.2011.08.003
PLACENTAL AND FETAL PREECLAMPSIA L3. Trophoblast invasion and spiral artery transformation in pre-eclampsia and fetal growth restriction Fiona Lyall a, Judith Bulmer b, Robert Pijnenborg c, Helen Simpson b, Stephen Robson b (a Institute of Medical Genetics, University of Glasgow, UK, b University of Newcastle, Newcastle, UK, c University Hospital Gasthuisberg, Leuven, Belgium) Failure of physiological changes in maternal spiral arteries has been linked to adverse maternal and fetal outcome. We have systematically examined the morphological changes that take place in the placental bed in pre-eclampsia (PE), fetal growth restriction (FGR) and uncomplicated control pregnancies (con). Placental bed sampling has been described in detail previously (1). Biopsies were obtained from 25 con pregnancies, 22 cases of PE and 10 cases of severe FGR. Frozen sections were immunostained with antibodies against defined cell types or cell components (2). A semi-quantitative scale (2) with some modifications was used to assess spiral artery muscle integrity (preserved, separated, disorganised or grossly disorganised), endothelium integrity, interstitial and endovascular cytotrophoblast
240
Lectures / Pregnancy Hypertension: An International Journal of Women’s Cardiovascular Health 1 (2011) 238–272
(CTB) invasion, intramural CTB and fibrinoid deposition. Data were analysed using the Stata package & SPSS. Regression analysis allowed for the multiple factors scored and repeated observations on the same subject. p < 0.05 was considered significant. In PE decidual vessel wall modification was not significantly different compared to con pregnancies. In contrast, in the myometrial segments, there were no preserved vessels in the con group but 27% were preserved in the PE group. Overall both PE and FGR cases both contained significantly more preserved myometrial vessels (p > 0.0001). Next all 3 groups were combined to explore the relationship between birthweight centile and physiological changes, In myometrial, but not decidual vessels, birthweights <5th centile were much more likely to be associated with preservation of vessels (p < 0.01). Interstitial CTB invasion (CTB in the decidua or myometrium) was not different between groups in the decidual area but in the myometrial area FGR (but not PE) had significantly more interstitial CTB (p < 0.05 control v FGR). Endovascular CTB was not significantly different between groups. No differences were found in intramural CTB in decidual vessels between normal and PE but in myometrial vessels intramural CTB was significantly reduced by about 50% (p < 0.05) in PE. When all vessels were combined. when uterine artery doppler is abnormal then vessels are more likely to be more preserved (p < 0.05). When umbilical artery Doppler is abnormal then media of myometrial vessels is more likely to be more preserved (p < 0.05). Finally, the an analysis to test whether the more a vessel was disrupted the more likely the amount of fibrinoid deposited increased showed: decidual vessels: con v PE, n.s., con v FGR p < 0.02. Myometrial vessels: con v PE (p < 0.0001) and con v FGR p < 0.02. Using a unique and novel sampling technique along with modern immunostaining techniques has further increased the knowledge of the changes in the placental bed in PE and FGR. Sponsored by BHF and Action Research. Am J Obstet Gynecol 2002;187(5):1349–5. J Pathol 2006;208(4):535–42. doi:10.1016/j.preghy.2011.08.004
L4. Placental inflammatory factors and preeclampsia Chiara Voltolini, Romina Novembri, Alberto Imperatore, Michela Torricelli, John Challis, Felice Petraglia (Obstetrics and Gynaecology, University of Siena, Siena, Italy) Preeclampsia originates in the placenta and results from imbalance between factors produced by this organ and maternal adaptation to them. Although the complex pathogenesis, recent evidences attest that deregulation of the immune system and exaggeration of inflammatory processes represent central mechanisms occurring with the disease. Although immunity/inflammation are physiologically involved in the establishment and maintenance of pregnancy, in susceptible cases the presence of perturbations in organ functions (infection, hypoxia) may trigger excessive inflammatory processes ending in the development of complications such as preeclampsia. In preeclampsia the insufficient
utero-placental circulation and the subsequent placental hypoxia lead to increased placental expression of oxidative stress markers (VEGF, PlGF, sFlt-1, HIF-1) and intense inflammatory response, characterized by involvement of innate immune defence mechanisms (TLRs), activation of intracellular signalling (NFkB) and release of pro-inflammatory cytokines (TNF-a, IL-1, IL-6). Neuronal–hormonal-immune factors interact at various levels during pregnancy, modulating a large series of responses to stress. Concerning that, the corticotrophin releasing hormone (CRH), neuropeptide regulating the hypothalamo–pituitary–adrenal (HPA), plays a central role. During pregnancy CRH is mainly produced by placenta, that recapitulates the key activities of the HPA axis and interacts with maternal and fetal systems, orchestrating many adaptive mechanisms to pregnancy. Recently an increasing interest has been developed for the urocortins (Ucn, Ucn2, Ucn3) that belong to the CRH family and exert complementary or sometimes contrasting actions with CRH. Expressed by intrauterine tissues, urocortins bind the CRH receptors (CRHR1, CRHR2) with different affinity, since Ucn binds both of them whereas Ucn2 and Ucn3 bind only CRHR2. As our group demonstrated, in preeclampsia we assist to increased maternal plasma levels of CRH and Ucn, but if they are associated with increased CRH placental mRNA expression, Ucn in cord blood is higher than in maternal plasma while placental mRNA expression doesn’t change between controls and preeclampsia, suggesting a fetal source for this neuropetpide. More recently, a study from our group has shown that placental Ucn2 and Ucn3 mRNA expressions increase in early and late preeclampsia, and are sensitive to oxygen tensions likely trough HIF-1a mediation. These data, together with the findings that Ucn2 increases sFlt-1 mRNA expression in trophoblast placental cultures, suggest a possible implication for these neuropeptides in the placental oxidative stress associated to preeclampsia.Moreover, CRH and Ucns have shown to act as endogenous immunomodulatory factors in utero-placental tissues. In human placenta, CRH serves mainly a pro-inflammatory function, while Ucn shows anti-inflammatory effect, reverses LPS-induced secretion of TNF-a and increasing the basal secretion of IL-4 and IL-10. Ucn2 increases the pro-inflammatory while Ucn3 the antiinflammatory cytokines secretion in trophoblast cultures. In conclusion, CRH and Ucns modulate the response to the hypoxic and inflammatory stress in human placenta, suggesting their role as important mediators of the interactions between neuroendocrine and immune processes taking part to the onset and development of preeclampsia. doi:10.1016/j.preghy.2011.08.005
L5. Genetic aspects of preeclampsia L. Marozio a, E. Gibbone a, A. Tancredi a, C. Di Gaetano b, V. Biasoni a, G. Polarolo a, C. Benedetto a (a Department of Obstetrics and Gynaecology, University of Torino, Italy, b Department of Genetics, Biology and Biochemistry, University of Torino, Italy) The pathogenesis of preeclampsia is still enigmatic and several studies have proposed that it may, in part, be deter-
promptly treated with acyclovir. Differential diagnosis may be difficult due to the overlap of several clinical and laboratory findings of these syndrome (Table 1). It is important that the clinician make the accurate diagnosis when possible because the management and complications from these syndromes may be different. For example, severe preeclampsia and AFLP are treated by delivery, whereas it is possible to continue pregnancy in those with TTP/HUS, and exacerbation of SLE. This review focuses on diagnosis, management, and counseling of women who develop these syndromes based on results of recent studies. doi:10.1016/j.preghy.2011.08.002
L2. Clinical utility of placental growth factor – Pathological insights from commercial assays Christopher Redman (University of Oxford, UK) Placental growth factor (PlGF) is a proangiogenic marker which has been identified as having potential clinical utility in the diagnosis and outcome prediction of women with hypertensive disorders of pregnancy. We consider here the available data and the insights that they bring to the potential management of these conditions. PlGF levels increase to week 32 and then decrease until term. In preeclampsia, there is increased release of its soluble receptor soluble fms-like tyrosine kinase-1 (sFlt1) from the placenta in response to oxidative and inflammatory stress, which binds to circulating vascular growth factors, including PlGF. As a consequence, circulating levels of noncomplexed PlGF are decreased in women with preeclampsia. There is consistent evidence of a strong correlation between altered levels of PlGF and sFlt-1 in pregnant women with preeclampsia [2]. Several immunoassays now exist to measure PlGF, with differing analytical specificity. We compared the new point-of-care immunoassay Triage PlGF (Alere) to an established research immunoassay, the Quantikine PlGF ELISA (R&D Systems). The median PlGF concentration measured on Triage PlGF, compared to the ELISA, was 4.5-fold lower for cases compared to only 1.5-fold lower in controls [1]. Benton et al. compared the performance of the immunoassays Triage PlGF and Elecsys sFlt-1/PlGF ratio (Roche). Both assays had optimal performance in diagnosing earlyonset preeclampsia with area under ROC curves of 0.99 (Triage 100% sensitivity, 96% specificity; Elecsys 64% sensitivity, 100% specificity for early-onset preeclampsia). The median PlGF concentration measured on Triage PlGF, compared to the Elecsys PlGF assay, was 5.2-fold lower for cases compared to only 1.6-fold lower in controls [3]. Stenczer measured PlGF concentration in HELLP syndrome, superimposed pre-eclampsia and pre-eclampsia, and from women with a final diagnosis of either chronic or new onset hypertension. Samples were collected from woman at diagnosis before 35 weeks GA. Low levels of PlGF at diagnosis were observed in 92% of women with proteinuric hypertension and 54% of women with non-proteinuric hypertension. Stenczer et al. [4] also studied time interval between blood draw and delivery in these women. PlGF was analysed
239
retrospectively and did not influence decision to deliver. Independent of diagnosis, PlGF concentration was associated with length of pregnancy after blood draw. PlGF concentration was significantly lower in women delivering preterm and lowest in women delivering before 35 weeks. The area under the ROC curve was 0.94 for the ability of PlGF to differentiate preterm from term delivery. In conclusion, PlGF increases throughout pregnancy to week 32, then decreases until term. The available assays differ in their specificity for the known isoforms and non-complexed PlGF, and this might explain the observed differences in discrimination of cases from controls between assays. At diagnosis before 35 weeks gestation, PlGF concentrations potentially predict length of pregnancy, indicating which women will deliver pre-term not only in pre-eclampsia, HELLP and superimposed pre-eclampsia, but also in nonproteinuric hypertension, causing us to re-consider how we assess risk in this latter group. Larger prospective studies are needed to confirm the potential of PlGF. References Redman C, Lodge T, Meacher H, Marks J, Simms C, Sargent I. Triage PLGF test: point-of-care assay of plasma placental growth factor to diagnose preeclampsia. Adv Perinat Med 2010. Levine RJ, Maynard SE, Qian C, et al. Circulating angiogenic factors and the risk of preeclampsia. N Engl J Med ];350:672–83. Benton SJ, Hu Y, Xie F, Kupfer K, Lee SW, Magee LA, von Dadelszen P. Angiogenic factors as diagnostic tests for pre-eclampsia: a performance comparison between two commercial immunoassays. Am J Obstet Gynecol 2011. doi:10.1016/j.ajog.2011.06.058. Stenczer B, et al. Evaluation of a new simple and rapid placental growth factor test for the evaluation of hypertensive disorders of pregnancy. International Federation of Placenta Associations, 2011 (accepted abstract). doi:10.1016/j.preghy.2011.08.003
PLACENTAL AND FETAL PREECLAMPSIA L3. Trophoblast invasion and spiral artery transformation in pre-eclampsia and fetal growth restriction Fiona Lyall a, Judith Bulmer b, Robert Pijnenborg c, Helen Simpson b, Stephen Robson b (a Institute of Medical Genetics, University of Glasgow, UK, b University of Newcastle, Newcastle, UK, c University Hospital Gasthuisberg, Leuven, Belgium) Failure of physiological changes in maternal spiral arteries has been linked to adverse maternal and fetal outcome. We have systematically examined the morphological changes that take place in the placental bed in pre-eclampsia (PE), fetal growth restriction (FGR) and uncomplicated control pregnancies (con). Placental bed sampling has been described in detail previously (1). Biopsies were obtained from 25 con pregnancies, 22 cases of PE and 10 cases of severe FGR. Frozen sections were immunostained with antibodies against defined cell types or cell components (2). A semi-quantitative scale (2) with some modifications was used to assess spiral artery muscle integrity (preserved, separated, disorganised or grossly disorganised), endothelium integrity, interstitial and endovascular cytotrophoblast
240
Lectures / Pregnancy Hypertension: An International Journal of Women’s Cardiovascular Health 1 (2011) 238–272
(CTB) invasion, intramural CTB and fibrinoid deposition. Data were analysed using the Stata package & SPSS. Regression analysis allowed for the multiple factors scored and repeated observations on the same subject. p < 0.05 was considered significant. In PE decidual vessel wall modification was not significantly different compared to con pregnancies. In contrast, in the myometrial segments, there were no preserved vessels in the con group but 27% were preserved in the PE group. Overall both PE and FGR cases both contained significantly more preserved myometrial vessels (p > 0.0001). Next all 3 groups were combined to explore the relationship between birthweight centile and physiological changes, In myometrial, but not decidual vessels, birthweights <5th centile were much more likely to be associated with preservation of vessels (p < 0.01). Interstitial CTB invasion (CTB in the decidua or myometrium) was not different between groups in the decidual area but in the myometrial area FGR (but not PE) had significantly more interstitial CTB (p < 0.05 control v FGR). Endovascular CTB was not significantly different between groups. No differences were found in intramural CTB in decidual vessels between normal and PE but in myometrial vessels intramural CTB was significantly reduced by about 50% (p < 0.05) in PE. When all vessels were combined. when uterine artery doppler is abnormal then vessels are more likely to be more preserved (p < 0.05). When umbilical artery Doppler is abnormal then media of myometrial vessels is more likely to be more preserved (p < 0.05). Finally, the an analysis to test whether the more a vessel was disrupted the more likely the amount of fibrinoid deposited increased showed: decidual vessels: con v PE, n.s., con v FGR p < 0.02. Myometrial vessels: con v PE (p < 0.0001) and con v FGR p < 0.02. Using a unique and novel sampling technique along with modern immunostaining techniques has further increased the knowledge of the changes in the placental bed in PE and FGR. Sponsored by BHF and Action Research. Am J Obstet Gynecol 2002;187(5):1349–5. J Pathol 2006;208(4):535–42. doi:10.1016/j.preghy.2011.08.004
L4. Placental inflammatory factors and preeclampsia Chiara Voltolini, Romina Novembri, Alberto Imperatore, Michela Torricelli, John Challis, Felice Petraglia (Obstetrics and Gynaecology, University of Siena, Siena, Italy) Preeclampsia originates in the placenta and results from imbalance between factors produced by this organ and maternal adaptation to them. Although the complex pathogenesis, recent evidences attest that deregulation of the immune system and exaggeration of inflammatory processes represent central mechanisms occurring with the disease. Although immunity/inflammation are physiologically involved in the establishment and maintenance of pregnancy, in susceptible cases the presence of perturbations in organ functions (infection, hypoxia) may trigger excessive inflammatory processes ending in the development of complications such as preeclampsia. In preeclampsia the insufficient
utero-placental circulation and the subsequent placental hypoxia lead to increased placental expression of oxidative stress markers (VEGF, PlGF, sFlt-1, HIF-1) and intense inflammatory response, characterized by involvement of innate immune defence mechanisms (TLRs), activation of intracellular signalling (NFkB) and release of pro-inflammatory cytokines (TNF-a, IL-1, IL-6). Neuronal–hormonal-immune factors interact at various levels during pregnancy, modulating a large series of responses to stress. Concerning that, the corticotrophin releasing hormone (CRH), neuropeptide regulating the hypothalamo–pituitary–adrenal (HPA), plays a central role. During pregnancy CRH is mainly produced by placenta, that recapitulates the key activities of the HPA axis and interacts with maternal and fetal systems, orchestrating many adaptive mechanisms to pregnancy. Recently an increasing interest has been developed for the urocortins (Ucn, Ucn2, Ucn3) that belong to the CRH family and exert complementary or sometimes contrasting actions with CRH. Expressed by intrauterine tissues, urocortins bind the CRH receptors (CRHR1, CRHR2) with different affinity, since Ucn binds both of them whereas Ucn2 and Ucn3 bind only CRHR2. As our group demonstrated, in preeclampsia we assist to increased maternal plasma levels of CRH and Ucn, but if they are associated with increased CRH placental mRNA expression, Ucn in cord blood is higher than in maternal plasma while placental mRNA expression doesn’t change between controls and preeclampsia, suggesting a fetal source for this neuropetpide. More recently, a study from our group has shown that placental Ucn2 and Ucn3 mRNA expressions increase in early and late preeclampsia, and are sensitive to oxygen tensions likely trough HIF-1a mediation. These data, together with the findings that Ucn2 increases sFlt-1 mRNA expression in trophoblast placental cultures, suggest a possible implication for these neuropeptides in the placental oxidative stress associated to preeclampsia.Moreover, CRH and Ucns have shown to act as endogenous immunomodulatory factors in utero-placental tissues. In human placenta, CRH serves mainly a pro-inflammatory function, while Ucn shows anti-inflammatory effect, reverses LPS-induced secretion of TNF-a and increasing the basal secretion of IL-4 and IL-10. Ucn2 increases the pro-inflammatory while Ucn3 the antiinflammatory cytokines secretion in trophoblast cultures. In conclusion, CRH and Ucns modulate the response to the hypoxic and inflammatory stress in human placenta, suggesting their role as important mediators of the interactions between neuroendocrine and immune processes taking part to the onset and development of preeclampsia. doi:10.1016/j.preghy.2011.08.005
L5. Genetic aspects of preeclampsia L. Marozio a, E. Gibbone a, A. Tancredi a, C. Di Gaetano b, V. Biasoni a, G. Polarolo a, C. Benedetto a (a Department of Obstetrics and Gynaecology, University of Torino, Italy, b Department of Genetics, Biology and Biochemistry, University of Torino, Italy) The pathogenesis of preeclampsia is still enigmatic and several studies have proposed that it may, in part, be deter-