Karolinska Research Articles

Uniting diversity to create a more inclusive academic environment.

Uniting diversity to create a more inclusive academic environment.

Association of maternal polycystic ovary syndrome and diabetes with preterm birth and offspring birth size: a population-based cohort study.

Association of maternal polycystic ovary syndrome and diabetes with preterm birth and offspring birth size: a population-based cohort study.

Evaluation of science advice during the COVID-19 pandemic in Sweden

Sweden was well equipped to prevent the pandemic of COVID-19 from becoming serious. Over 280 years of collaboration between political bodies, authorities, and the scientific community had yielded many successes in preventive medicine. Sweden’s population is literate and has a high level of trust in authorities and those in power. During 2020, however, Sweden had ten times higher COVID-19 death rates compared with neighbouring Norway. In this report, we try to understand why, using a narrative approach to evaluate the Swedish COVID-19 policy and the role of scientific evidence and integrity. We argue that that scientific methodology was not followed by the major figures in the acting authorities—or the responsible politicians—with alternative narratives being considered as valid, resulting in arbitrary policy decisions. In 2014, the Public Health Agency, after 5 years of rearrangement, merged with the Institute for Infectious Disease Control, with six professors leaving between 2010 and 2012 going to the Karolinska Institute. With this setup, the authority lost scientific expertise. The Swedish pandemic strategy seemed targeted towards “natural” herd-immunity and avoiding a societal shutdown. The Public Health Agency labelled advice from national scientists and international authorities as extreme positions, resulting in media and political bodies to accept their own policy instead. The Swedish people were kept in ignorance of basic facts such as the airborne SARS-CoV-2 transmission, that asymptomatic individuals can be contagious and that face masks protect both the carrier and others. Mandatory legislation was seldom used; recommendations relying upon personal responsibility and without any sanctions were the norm. Many elderly people were administered morphine instead of oxygen despite available supplies, effectively ending their lives. If Sweden wants to do better in future pandemics, the scientific method must be re-established, not least within the Public Health Agency. It would likely make a large difference if a separate, independent Institute for Infectious Disease Control is recreated. We recommend Sweden begins a self-critical process about its political culture and the lack of accountability of decision-makers to avoid future failures, as occurred with the COVID-19 pandemic.

German Camejo (1936–2021)

German Camejo (1936–2021)

Epigenetics in the Anthropocene: an interview with Oskar Karlsson.

In this interview, Oskar Karlsson speaks with Storm Johnson, commissioning editor for Epigenomics, on his work to date in the field of toxicological origins of disease and gene-environment interactions. Oskar Karlsson, is an associate professor at the Science for Life Laboratory (SciLifeLab), Department of Environmental Science, Stockholm University, Sweden. Dr. Karlsson earned a PhD in toxicology at the Department of Pharmaceutical Bioscience, Uppsala University, and has also worked at Centre of Molecular Medicine, Karolinska Institute, as well as Harvard UniversitySchool of Public Health. His research combines experimental model systems, computational and omics tools, and epidemiological studies to investigate the influence of environmental exposures on wildlife and human health, and underlying molecular mechanisms. In particular, his research focuses on developmental origins of health and disease with an emphasis on environmental exposures and epigenetic mechanisms. The projects concern the effects of exposures such as endocrine disrupting chemicals, flame retardants, pesticides, metals andparticulate air pollution, as well as drugs, psycho-social stressorsand ethnical disparities. Ongoing efforts include studies of paternal epigenetic inheritance in the ERC-funded project PATER.

Multiple therapeutic effects of human neural stem cells derived from induced pluripotent stem cells in a rat model of post-traumatic syringomyelia.

SummaryBackgroundPost-traumatic syringomyelia (PTS) affects patients with chronic spinal cord injury (SCI) and is characterized by progressive deterioration of neurological symptoms. To improve surgical treatment, we studied the therapeutic effects of neuroepithelial-like stem cells (NESCs) derived from induced pluripotent stem cells (iPSCs) in a rat model of PTS. To facilitate clinical translation, we studied NESCs derived from Good Manufacturing Practice (GMP)-compliant iPSCs.MethodsHuman GMP-compliant iPSCs were used to derive NESCs. Cryo-preserved NESCs were used off-the-shelf for intraspinal implantation to PTS rats 1 or 10 weeks post-injury, and rats were sacrificed 10 weeks later. In vivo cyst volumes were measured with micro-MRI. Phenotypes of differentiated NESCs and host responses were analyzed by immunohistochemistry.FindingsOff-the-shelf NESCs transplanted to PTS rats 10 weeks post-injury reduced cyst volume. The grafted NESCs differentiated mainly into glial cells. Importantly, NESCs also stimulated tissue repair. They reduced the density of glial scars and neurite-inhibiting chondroitin sulfate proteoglycan 4 (CSPG4), stimulated host oligodendrocyte precursor cells to migrate and proliferate, reduced active microglia/macrophages, and promoted axonal regrowth after subacute as well as chronic transplantation.InterpretationSignificant neural repair promoted by NESCs demonstrated that human NESCs could be used as a complement to standard surgery in PTS. We envisage that future PTS patients transplanted with NESCs will benefit both from eliminating the symptoms of PTS, as well as a long-term improvement of the neurological symptoms of SCI.FundingThis work was supported by Vinnova (2016-04134), Karolinska Institutet StratRegen, and the Chinese Scholarship Council.

Abstract P1-07-07: Endoresist: Prognostic and predictive gene profiles in endocrine-resistant breast cancers

Abstract Background:. Up to 75% of breast cancer patients have tumors expressing the predictive biomarker estrogen receptor alpha (ER) and are consequently offered endocrine therapy. Approximately one third eventually relapse in their disease with the majority still expressing ER but resistant to one or several types of endocrine-based therapies. Molecular studies of ER-signaling suggest several potential factors influencing endocrine response such as ER structural and functional domains, posttranslational modifications and unbalanced receptor and co-regulator activity with alterations in downstream signaling pathways. However, the mechanism behind endocrine resistance is elusive and tumor cell expression of ER is the only clinically utilized biomarker for endocrine therapeutic response. This calls for a broader understanding of the resistance process in order to develop novel tools for therapy prediction and treatment alternatives. This study aims to improve our understanding of the underlying mechanism behind endocrine resistance and to identify biomarkers for an individualized approach to cancer therapy. Materials and methods:. A cohort comprising verified endocrine-resistant early breast cancer diagnosed in 2005-2006 and 2008-2014 at the Karolinska University Hospital, Stockholm, Sweden was retrospectively collected. Patients with ER+ and human epidermal growth factor receptor 2 (HER2)- primary breast cancer who had an ER+/HER2- relapse tumor during ongoing endocrine therapy (<5 years from diagnosis) were included as cases, with both primary tumors (n=68) and relapse tumors (n=67). A control cohort was selected consisting of patients with ER+/HER2- early breast cancer diagnosed in 2005, without relapse or disease progression at 10 years of follow-up (n=78), and matched to cases (2:1 ratio) by age and tumor stage. To determine the transcriptomic and genomic profiles, RNA and DNA were extracted from archived formalin-fixed paraffin-embedded tumor tissue. RNA samples were analyzed using Affymetrix DNA Microarray with Clariom D Chip and assessed through Transcriptome Array Console and R. DNA was analyzed through panel sequencing (GMCK gene panel consisting of 370 genes and a size of 2,4 Mb intended for genetic screening of solid tumors) with following assessments in R. Results:. The preliminary transcriptomic analysis showed several differentially expressed pathways and specific genes that differentiate both the primary tumors of cases that eventually relapse during endocrine therapy compared to controls, as well as between the cases’ relapses and their corresponding primary tumors. Intrinsic analyses show upregulation in tumor-driving pathways such as PI3K signaling pathway, androgen receptor and cell adhesion pathways in primary tumors of cases versus controls. This has further been investigated by gene analysis where genes such as PIK3CA, PTEN, CDK4/6 and ESR1 were upregulated between the groups. In the analysis of relapses compared to their primary tumors, pathways involving apoptosis and response to hypoxia were downregulated as well as specific genes such as IGF1R, whereas pathways including immune response were upregulated. Conclusion:. Our study suggests that endocrine resistant tumors are associated with distinct genomic and transcriptomic profiles that potentially could be utilized as predictive and prognostic markers for endocrine resistant breast cancer. These preliminary results can guide further investigations deciphering the mechanisms of endocrine resistance in breast cancer. This trial is a non-interventional study set up as a research collaboration between Karolinska Institutet and Novartis Sweden AB. Citation Format: Caroline Schagerholm, Stephanie Robertson, Barbro Holm, Karolina Lindberg, Emmanouil Sifakis, Linnea Hases, Cecilia Williams, Johan Hartman. Endoresist: Prognostic and predictive gene profiles in endocrine-resistant breast cancers [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-07-07.

Repression of hypoxia-inducible factor-1 contributes to increased mitochondrial reactive oxygen species production in diabetes.

Excessive production of mitochondrial reactive oxygen species (ROS) is a central mechanism for the development of diabetes complications. Recently, hypoxia has been identified to play an additional pathogenic role in diabetes. In this study, we hypothesized that ROS overproduction was secondary to the impaired responses to hypoxia due to the inhibition of hypoxia-inducible factor-1 (HIF-1) by hyperglycemia. The ROS levels were analyzed in the blood of healthy subjects and individuals with type 1 diabetes after exposure to hypoxia. The relation between HIF-1, glucose levels, ROS production and its functional consequences were analyzed in renal mIMCD-3 cells and in kidneys of mouse models of diabetes. Exposure to hypoxia increased circulating ROS in subjects with diabetes, but not in subjects without diabetes. High glucose concentrations repressed HIF-1 both in hypoxic cells and in kidneys of animals with diabetes, through a HIF prolyl-hydroxylase (PHD)-dependent mechanism. The impaired HIF-1 signaling contributed to excess production of mitochondrial ROS through increased mitochondrial respiration that was mediated by Pyruvate dehydrogenase kinase 1 (PDK1). The restoration of HIF-1 function attenuated ROS overproduction despite persistent hyperglycemia, and conferred protection against apoptosis and renal injury in diabetes. We conclude that the repression of HIF-1 plays a central role in mitochondrial ROS overproduction in diabetes and is a potential therapeutic target for diabetic complications. These findings are timely since the first PHD inhibitor that can activate HIF-1 has been newly approved for clinical use. This work was supported by grants from the Swedish Research Council, Stockholm County Research Council, Stockholm Regional Research Foundation, Bert von Kantzows Foundation, Swedish Society of Medicine, Kung Gustaf V:s och Drottning Victorias Frimurarestifelse, Karolinska Institute's Research Foundations, Strategic Research Programme in Diabetes, and Erling-Persson Family Foundation for S-B.C.; grants from the Swedish Research Council and Swedish Heart and Lung Foundation for T.A.S.; and ERC consolidator grant for M.M.

Uterine fluid microRNAs are dysregulated in women with recurrent implantation failure.

STUDY QUESTIONIs the composition of microRNAs (miRNAs) in uterine fluid (UF) of women with recurrent implantation failure (RIF) different from that of healthy fertile women?SUMMARY ANSWERThe composition of miRNAs in UF of women with RIF is different from that of healthy fertile women and the dysregulated miRNAs are associated with impaired endometrial receptivity and embryo implantation.WHAT IS KNOWN ALREADYIt has previously been demonstrated that the miRNAs secreted from endometrial cells into the UF contribute to the achievement of endometrial receptivity. Endometrial miRNAs are dysregulated in women with RIF.STUDY DESIGN, SIZE, DURATIONIn this descriptive laboratory case–control study, miRNA abundancy was compared between UF collected during implantation phase from healthy fertile women (n = 17) and women with RIF (n = 34), which was defined as three failed IVF cycles with high-quality embryos.PARTICIPANTS/MATERIALS, SETTING, METHODSRecruitment of study subjects and sampling of UF were performed at two university clinics in Stockholm, Sweden and Tartu, Estonia. The study participants monitored their menstrual cycles using an LH test kit. The UF samples were collected on Day LH + 7–9 by flushing with saline. Samples were processed for small RNA sequencing and mapped for miRNAs. The differential abundance of miRNAs in UF was compared between the two groups using differential expression analysis (DESeq2). Further downstream analyses, including miRNA target gene prediction (miRTarBase), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis (g:Profiler) and external validation using relevant published data, were performed on the dysregulated miRNAs. Two miRNAs were technically validated with quantitative real-time PCR (RT-PCR).MAIN RESULTS AND THE ROLE OF CHANCEAfter processing of the sequencing data, there were 15 samples in the healthy fertile group and 33 samples in the RIF group. We found 61 differentially abundant UF miRNAs (34 upregulated and 27 downregulated) in RIF compared to healthy women with a false discovery rate of <0.05 and a fold change (FC) of −2 or 2. When analyzed with published literature, we found that several of the differentially abundant miRNAs are expressed in endometrial epithelial cells and have been reported in endometrial extracellular vesicles and in association with endometrial receptivity and RIF. Their predicted target genes were further expressed both in the trophectodermal cells of blastocyst-stage embryos and endometrial mid-secretory epithelial cells, as assessed by publicly available single-cell transcriptome-sequencing studies. Pathway analysis further revealed that 25 pathways, having key roles in endometrial receptivity and implantation, were significantly enriched. Hsa-miR-486-5p (FC −20.32; P-value = 0.004) and hsa-miR-92b-3p (FC −9.72; P-value = 0.004) were successfully technically validated with RT-PCR.LARGE SCALE DATAThe data are available in Gene Expression Omnibus (GEO) at https://www.ncbi.nlm.nih.gov/geo/ with GEO accession number: GSE173289.LIMITATIONS, REASONS FOR CAUTIONThis is a descriptive study with a limited number of study participants. Moreover, the identified differentially abundant miRNAs should be validated in a larger study cohort, and the predicted miRNA target genes and enriched pathways in RIF need to be confirmed and further explored in vitro.WIDER IMPLICATIONS OF THE FINDINGSRIF is a major challenge in the current IVF setting with no diagnostic markers nor effective treatment options at hand. For the first time, total miRNAs have been extensively mapped in receptive phase UF of both healthy women with proven fertility and women diagnosed with RIF. Our observations shed further light on the molecular mechanisms behind RIF, with possible implications in future biomarker and clinical treatment studies.STUDY FUNDING/COMPETING INTEREST(S)This work was financially supported by the Swedish Research Council (2017-00932), a joint grant from Region Stockholm and Karolinska Institutet (ALF Medicine 2020, FoUI-954072), Estonian Research Council (PRG1076), Horizon 2020 innovation (ERIN, EU952516) and European Commission and Enterprise Estonia (EU48695). The authors have no competing interests to declare for the current study.

COVID-19 vaccine inequity, dependency, and production capability in low-income and middle-income countries: the case of Bangladesh

COVID-19 vaccine inequity, dependency, and production capability in low-income and middle-income countries: the case of Bangladesh

Salivary IgG to SARS-CoV-2 indicates seroconversion and correlates to serum neutralization in mRNA-vaccinated immunocompromised individuals

BackgroundImmunocompromised individuals are highly susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Whether vaccine-induced immunity in these individuals involves oral cavity, a primary site of infection, is presently unknown.MethodsImmunocompromised patients (n = 404) and healthy controls (n = 82) participated in a prospective clinical trial (NCT04780659) encompassing two doses of the mRNA BNT162b2 vaccine. Primary immunodeficiency (PID), secondary immunodeficiencies caused by human immunodeficiency virus (HIV) infection, allogeneic hematopoietic stem cell transplantation (HSCT)/chimeric antigen receptor T cell therapy (CAR-T), solid organ transplantation (SOT), and chronic lymphocytic leukemia (CLL) patients were included. Salivary and serum immunoglobulin G (IgG) reactivities to SARS-CoV-2 spike were measured by multiplex bead-based assays and Elecsys anti-SARS-CoV-2 S assay.FindingsIgG responses to SARS-CoV-2 spike antigens in saliva in HIV and HSCT/CAR-T groups were comparable to those of healthy controls after vaccination. The PID, SOT, and CLL patients had weaker responses, influenced mainly by disease parameters or immunosuppressants. Salivary responses correlated remarkably well with specific IgG titers and the neutralizing capacity in serum. Receiver operating characteristic curve analysis for the predictive power of salivary IgG yielded area under the curve (AUC) = 0.95 and positive predictive value (PPV) = 90.7% for the entire cohort after vaccination.ConclusionsSaliva conveys vaccine responses induced by mRNA BNT162b2. The predictive power of salivary spike IgG makes it highly suitable for screening vulnerable groups for revaccination.FundingKnut and Alice Wallenberg Foundation, Erling Perssons family foundation, Region Stockholm, Swedish Research Council, Karolinska Institutet, Swedish Blood Cancer Foundation, PID patient organization of Sweden, Nordstjernan AB, Center for Medical Innovation (CIMED), Swedish Medical Research Council, and Stockholm County Council (ALF).

Wearables and smart skin as new tools for clinical practice and research in dermatology

Wearables and smart skin as new tools for clinical practice and research in dermatology

Integrated antimicrobial resistance management strategy: A way forward to mitigate antimicrobial resistance crisis.

1Department of Environmental Medicine, Indian Initiative for Management for Antimicrobial Resistance, R.D. Gardi Medical College, Ujjain 456 001, India 2Division of Environmental Monitoring & Exposure Assessment (Water & Soil), ICMR- National Institute for Research in Environmental Health, Bhopal 462 030, Madhya Pradesh, India 3Department of Global Public Health, Karolinska Institutet, Stockholm 17177, Sweden For correspondence: [email protected] Received August 04, 2021 This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 4.0 Unported, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Mitochondria to Bitter Melon: Understanding the 3D Ultrastructure of the Cell Via 2D Thin Section Reconstruction and the History of Mitochondrial Visualization.

The origin of histology-the study of microscopic anatomy-is intimately connected with the development of the light microscope and improvements in lens design and manufacture.However, knowledge of the ultrastructure of the cell was hampered by the very nature of light microscopy, which, due to the physical properties of the visible electromagnetic spectrum, could never provide the magnification and resolution for study of the granules seen in cells, which we now know as the organelles. When the electron microscope was developed in the 1930s, a beam of electrons replaced light as the source of illumination, and the inner details of the cell could be observed directly. With thin sections obtained by transmission electron microscopy, cell biologists could embark on the task of reconstructing 3D microstructure via the painstaking stacking of the individual slices.The three-dimensional visualization of the mitochondrion was particularly challenging, as its convoluted structure could be interpreted in several ways based on differences observed by George Palade at the Rockefeller Institute for Medical Research (NYC), and Fritiof Sjöstrand at the Karolinska Institutet (Stockholm). Palade's interpretation was eventually accepted as correct due to its alignment with the findings of biochemists investigating the cascade of molecular interactions known as the Krebs cycle, responsible for the production of cellular energy in the form of adenosine triphosphate (ATP). However, it can also be argued that Palade's visualization via a physical model of the mitochondrion, which he built with sheets of wax, photographed, and published in 1953, better enabled colleagues to comprehend its unique inner structures known as cristae.To teach undergraduate science students about this pivotal moment in cell biology and add to their understanding of the reconstruction process, a pedagogical exercise was created in which students are provided with outline drawings of various organic objects cut in random planes of section. Working individually at first, and then in groups, they are tasked with collaborating to devise an accurate description of the shape and texture of the object. After their observations are presented to the class, they are shown a photo of the object prior to its sectioning to determine if their observations were correct.

Study protocol for a prospective cohort study identifying risk factors for sport injury in adolescent female football players: the Karolinska football Injury Cohort (KIC)

IntroductionFootball is a popular sport among young females worldwide, but studies concerning injuries in female players are scarce compared with male players. The aim of this study is to identify...

Optimizing risk-based breast cancer screening policies with reinforcement learning

Screening programs must balance the benefit of early detection with the cost of overscreening. Here, we introduce a novel reinforcement learning-based framework for personalized screening, Tempo, and demonstrate its efficacy in the context of breast cancer. We trained our risk-based screening policies on a large screening mammography dataset from Massachusetts General Hospital (MGH; USA) and validated this dataset in held-out patients from MGH and external datasets from Emory University (Emory; USA), Karolinska Institute (Karolinska; Sweden) and Chang Gung Memorial Hospital (CGMH; Taiwan). Across all test sets, we find that the Tempo policy combined with an image-based artificial intelligence (AI) risk model is significantly more efficient than current regimens used in clinical practice in terms of simulated early detection per screen frequency. Moreover, we show that the same Tempo policy can be easily adapted to a wide range of possible screening preferences, allowing clinicians to select their desired trade-off between early detection and screening costs without training new policies. Finally, we demonstrate that Tempo policies based on AI-based risk models outperform Tempo policies based on less accurate clinical risk models. Altogether, our results show that pairing AI-based risk models with agile AI-designed screening policies has the potential to improve screening programs by advancing early detection while reducing overscreening.

The 12 women who won the Nobel Prize in Medicine or Physiology

Introduction: the Nobel Prize is one of the highest academic honors in the world. Since its first edition, in 1901, until 2021, there have been hundreds of winners. In the Medicine or Physiology category, chosen by the Karolinska Institute in Stockholm, Sweden, 112 awards have been given to 224 laureates, among them, only 12 (5.4%) women.Aims and source of data: with the aim of reviewing the biographies, characteristics, and peculiarities of each woman awarded the Nobel Prize for Medicine or Physiology. Data were analyzed from the following sources: the Award page, websites of the institutions to which some of them have been or are affiliated, books with biographies of Nobel laureates in Medicine or Physiology, and articles in the PubMed database.Summary of findings: the average age when receiving the award was 63.4 years. The most recurrent country of origin was the United States of America, also responsible for the largest number of institutions to which the laureates were affiliated at the time of the award. The academic training of the laureates was quite diverse, ranging among medicine, chemistry, physics, biology, pharmacy, psychology and natural sciences. Five of the 12 laureates did not have children.Comments: the origins and trajectories, although plural, have points in common, such as a fascination with science since childhood and the need to overcome additional barriers throughout their education, because of their sex.Conclusion: investments on a global scale are necessary to increase equity between sexes.

Patient and public involvement in oesophageal cancer survivorship research

Background Good clinical research is often conducted in close collaboration between patients, the public, and researchers. Few studies have reported the development of patient and public involvement (PPI) in research outside the United States and the United Kingdom, and for patients with more aggressive cancers. The study aimed to describe and evaluate the development of PPI in oesophageal cancer survivorship research in Sweden by the use of a framework to support the process. Methods Oesophageal cancer survivors were recruited to a PPI research collaboration at Karolinska Institutet, Sweden. The development process was supported by the use of a framework for PPI, ‘Patient and service user engagement in research’. Insights, benefits, and challenges of the process were described and discussed among the collaborators. Results The collaboration resulted in joint publications with a more patient- and family-focussed perspective. It also contributed to the development of information folders about survivorship after oesophageal cancer surgery and national conference arrangements for patients, their families, healthcare workers, and researchers. Since the PPI contributors were represented in patient organisations and care programmes, the dissemination of research results increased. Their contributions were highly valued by the researchers, but also revealed some challenges. The use of a structured framework contributed to support and facilitated the process of establishing PPI in research collaboration. Conclusions A genuine interest in establishing PPI in research and an understanding and respect for the patients’ expertise in providing a unique inside perspective was imperative for a successful collaboration. Research focus should not only be on mortality and reductions in daily life, but also on positive outcomes. Using a framework supports development and avoids pitfalls of PPI collaboration. Patient and public contribution Patient partners were equal collaborators in all aspects of the study.

Preparing children for operations

“On edge, suspicious, afraid, like a journey into the unknown, no explanation was given to me as to what to expect. That day I ran away from my own surgery. My mother found me by our car in the parking lot…we went home without having any surgery done.” So remembers Gunilla Lööf, now a Paediatric Nurse Anaesthetist at Karolinska Institute University Hospital, Sweden, thinking back to her first experience of surgery at age 5 years. Today, Lööf works on ways to prepare children for operations.

In Memoriam: Göran Hedenstierna (1941–2021)

On the 13th July 2021, Göran Hedenstierna, Professor of Clinical Physiology and Researcher in Anesthesia and Intensive Care Medicine, died at the age of 79 years. Prof. Göran Hedenstierna belongs to the generation of scientists who pioneered the scientific base of modern anesthesia and intensive care medicine. Göran was born in Göteborg (Sweden) in 1941 and attended the high school at the Blackeberg's gymnasium in Stockholm from 1952 to 1960. In 1961 he started the studies in medicine at Karolinska Institute where he received the M.D. in 1969.