DR STEFAN HANSSON An impressive career researching preeclampsia Being last year’s recipient of Sweden’s most prestigious clinical research prize, the Athena prize, is sure evidence that Dr Stefan Hansson’s work developing new diagnostics and treatments for preeclampsia has every potential to save lives and help to make an impact on women’s health You have produced several papers on preeclampsia so far and your work is ongoing. How do you hope this research will help to develop effective therapies? By discovering and understanding early mechanisms for preeclampsia, we believe that more specific therapies can be developed. Yearly, around 8.5 million cases of preeclampsia are reported worldwide, of which 5,000 are in Sweden. The unique potential therapy being developed in this translational project addresses a very important issue for women’s health during pregnancy and meets a major worldwide apparent clinical need. Our therapy will support the development of a specific, rather than symptomatic, treatment. Today the only curative intervention is to induce delivery, whether the baby is ready or not. It is estimated that US $30 billion is spent worldwide each year in healthcare costs to treat women with preeclampsia and their newborns. Our work will help to address this cost and help women with this disease around the world. What do you hypothesise is the likely cause of preeclampsia? Our gene and protein profiling studies have revealed a new potential aetiology for preeclampsia. The first stage, caused by a defect formation of the placenta, gives rise to uneven blood perfusion, oxidative stress, production and the accumulation of free foetal Hb (fHb). Stage two is characterised by a general, systemic endothelial damage and inflammation. Our recent results have shown that the free fHb cause inflammation and damage to the blood-placenta barrier. As a consequence, free fHb leaks over to the maternal blood circulation. The plasma concentration is increasing from early pregnancy and later correlates to the severity of the disease. Free fHb and its toxic metabolite heme are well known to have pro-inflammatory, pro-oxidative, kidney and endothelial damaging effects as well as inducing vasoconstriction by being an NO-scavenger. Hb is released from the red 38 INTERNATIONAL INNOVATION blood cells during haemolysis, which occurs in diseases like autoimmune haemolytic anaemia, sickle cell anaemia and malaria. In fact, free heme, bilirubin and biliverdin have been identified among the 14 metabolites in a metabolomics signature of preeclampsia using first trimester plasma. Free heme can enter cells by dissolving the cell membranes and possibly also the extracellular matrix. Is there a current method of prevention for this condition? Low dose asprin has some preventive effects if treatment is initiated early in pregnancy, however since it is difficult to identify high-risk pregnancies in early stages (first trimester), the numbers needed to treat is high (about 25). Can you explain what is meant by an ELISA technique? How is it used to diagnose preeclampsia? We have raised antibodies specific for free fHb and the adult form Hb-A by immunising with specific chains purified from cord blood fHb and adult blood, and developed ELISAs specific for free fHb and Hb-A. Statistical analysis shows that free fHb has a higher sensitivity and specificity than any other suggested biomarker for preeclampsia in early pregnancy. fHb levels have been shown to be increased in the mother’s blood in preeclampsia, in fact fHb is increased eight-fold in preeclampsia compared to controls. The prognostic value of free fHB will be further evaluated by measuring samples collected prospectively early in pregnancy in combination with alpha-1 microglobulin (A1M). In collaboration with Professor Baskaran Thilaganathan from London, a prospective cohort containing more than 60 preeclampsia women and matched controls have been followed from early pregnancy until delivery. Free fHb and Hb-A and A1M have been measured. Results from 96 cases show that free fHb levels can be measured as early as 10-14 weeks of gestation (when the uteroplacental circulation is established), several weeks before clinical manifestations are present. The three markers, free fHb, free adult Hb and A1M increased the sensitivity, specificity and the predictive value for diagnosing preeclampsia in the first trimester, when used in combination. Can you outline the methods taken to analyse genes and proteins? We have previously developed a preeclampsia specific gene chip, this will be further used to profile the gene expression in placentas perfused with free fHb ±A1M and compare to the gene expression profile obtained from different high-risk pregnancies, in order to better understand what placental genes that are essential in preeclampsia. To strengthen the analysis we have optimised our methods to also undertake protein profiling on placenta tissue and maternal plasma. We have optimised protein extraction procedures for placenta tissue. DR STEFAN HANSSON New drugs for an old disease A Swedish translational research team at Lund University is using free haemoglobin to develop a new preeclampsia prognostic/ diagnostic method and effective therapies for this serious disease PREECLAMPSIA IS A pregnancy disease that knows no boundaries: it crosses geographic and social borders, causes serious health problems and can potentially lead to the death of both the mother and child. Described as early as the Egyptian era, this disease has troubled scientists and medical experts for thousands of years. It is still one of the leading causes of death in unborn children and pregnant women. Currently, only symptomatic treatments are available, with delivery often being the last viable option for the most serious of cases. The disease is believed to initiate in the placenta, and a group of researchers are using the organ as a starting point to investigate possible biomarkers. They hope this work will help predict the onset of preeclampsia, ultimately paving the way towards new potential treatments. This research team is led by Dr Stefan Hansson, the Vice Dean for Research at the Medical Faculty of Lund University, who is also a professor and senior consultant in Obstetrics and Gynecology at Skåne University Hospital in southern Sweden. With preclinical training in research, Hansson can apply his molecular background to delve deeply into this clinically puzzling disease often called ‘the disease of theories’. Supported by a translational research group, Hansson has been building on findings from previous research into proteinand gene-array studies. These have highlighted the possibility that free foetal haemoglobin (fHb) may be an essential aetiological factor of preeclampsia, thus also potentially an ideal biomarker for prediction and diagnosis. Their latest research aims to discover whether a free haemoglobin scavenger, alpha-1microglobulin (A1M), might be used as a potential therapeutic drug. Currently, there are very few options available for the prevention or treatment of preeclampsia. Taking a low dose of aspirin has shown to have some beneficial effects, but falls short of offering a complete treatment for the disease. Part of the reason that an effective therapeutic option for the disease still evades scientists to date is because its clinical symptoms – which include high blood pressure, headaches and visual disturbances – only become evident once the disease has taken hold. A TWO STAGE DISEASE It is recognised that this disease evolves in two main stages. The first stage has been shown to take place when a defect invasion of the placental cells into the muscle layers of the spiral arteries occurs, which can put the baby at risk: “This may result in a reduced uteroplacental blood flow and afoetal intra-uterine growth restriction, reduced oxygen delivery and oxidative stress that further aggravate placental vascular function,” Hansson explains. The second stage consists of the clinical signs that occur later on during the pregnancy, by definition after 20 weeks. At this point, hypertension and proteinurea begin to manifest. As the disease progresses, the symptoms accelerate, with a generalised endothelial dysfunction that eventually affects all organs. When the disease moves into this end stage – known as eclampsia – severe epileptic seizures occur and if left untreated, may be fatal for both the mother and child. THE IMPORTANCE OF ‘NOTCHING’ One way to clinically elevate increased vascular resistance in the placenta is to use Doppler ultrasound techniques. By employing this tool, the occurrence of early diastolic notches as a sign of increased resistance in the utero-placental blood flow, high risk pregnancies can be identified, patients who have a significantly elevated risk of developing preeclampsia. Investigations have shown that the plasma level of serotonin and norepinephrine are significantly increased in preeclamptic patients. Hansson has been able to provide evidence, by demonstrated decreased expression of the norepinephrine and a steroid sensitive monoamine transporter in placentas in preeclamptic WWW.RESEARCHMEDIA.EU 39 INTELLIGENCE FREE HEMOGLOBIN IN PREECLAMPSIA ENABLE NEW DIAGNOSTIC AND TREATMENT OF PREECLAMPSIA OBJECTIVES This translational project intends to develop and validate fHb as a new potential marker for prediction and diagnosis of PE. Furthermore, the injury mechanism of fHb in PE will be examined and the therapeutic effect of alpha1-microglobulin as a scavenger evaluated as a new therapy. KEY COLLABORATOR Professor Bo Åkerström, Lund University FUNDING Preelumina Diagnostics AB • A1M Pharma AB • Torsten Söderbergs Foundation • Marianne and Marcus Wallenberg Foundation for Clinical Research • Maggie Stephens Foundation • Swedish Society for Medical Research • Region Skåne • ALF • Swedish Research Council • MENA/SIDA CONTACT Professor Stefan Hansson Project Leader Women’s Clinic, Prenatal Unit Skåne University Hospital (SUS) 205 02 Malmo Sweden T +46 40 332 976 Biomedical Center Institute Clinical Sciences Lund Department Obstetrics and Gynecology Lund University Sweden T +46 46 222 3011 E [email protected] STEFAN HANSSON works as Professor and Senior Consultant in Obstetrics and Gynecology at Lund University and Skåne University Hospital in southern Sweden. He is currently funded by the Marianne and Marcus Wallenberg foundation for clinical research, combining research and clinical work in equal proportions. As of March 2012, he is vice Dean for research at the medical faculty, Lund university. He is co-founder of two biotech companies, Preelumina Diagnostics and A1M Pharma, in which a new diagnostic kit and a new therapy for preeclampsia are being developed. The possibility of a treatment for preeclampsia is an exciting prospect for both researchers and patients pregnancies. This is an important discovery, since it emphasises that by inhibiting their uptake, the extracellular levels of the signal substances are increased, which ultimately affects the strength of the transmitted signal. The monoamine transporters in the placenta may protect the foetus from maternal stress hormones occurring in preeclampsia. Although this is an interesting finding in terms of building understanding of this disease, there is still much work to be done within this area of research. For example, cocaine abuse during pregnancy has been linked to triggering a preeclampsia-like state, which suggests that a monoaminergic imbalance might be central in the development of preeclampsia. “The reuptake of monoamines by the transporters is by far the most important mechanism by which the extra cellular concentrations of these substances are regulated, but their role in the placenta during pregnancy is not yet fully understood,” elucidates Hansson. THE VALUE OF BIOMARKERS Research undertaken on women with preeclampsia has illustrated that the levels of the free haemoglobin scavenger A1M are also elevated in maternal plasma and placenta tissue. This implies that the protein is involved in a defence-like reaction against the Hb-insult. By hypothesising that A1M, and other defence systems, are literally being overwhelmed when a patient suffers from preeclampsia, the research team consider that they can then treat this disease by adding an exogenously administrated recombinant A1M. Measuring biomarkers, such as free fHb and endogenous A1M, has allowed them to previously reveal that these can be used to predict preeclampsia at very early stages, in fact several weeks before the manifestations of this disease are seen on a clinical level. This in itself is a profound discovery, but from Hansson’s perspective, there are a number of other benefits that come from using free fHb and A1M as biomarkers. For instance, free fHb and A1M have higher sensitivity and specificity than any other generally used biomarker, and both these biomarkers provide the opportunity to develop a more personalised therapy. The new therapy could potentially be administered in two different ways. Firstly, in early pregnancy when increased levels of free fHb and A1M are detected, the A1M based drug can be offered to help inhibit the development of preeclampsia. Secondly, the levels of Hb correlate with the severity of the disease, therefore the dose of the A1M based drug can potentially be adjusted to the plasma levels of free Hb when preeclampsia has manifested. The possibility of a treatment for preeclampsia is an exciting prospect for both researchers and patients. Not only would it offer hope for women suffering from the disease, but it would also have a tremendous impact on women’s health all over the world. PHOTOGRAPHER CHARLOTTE CARLBERG BÄRG 40 INTERNATIONAL INNOVATION