Publications by authors named "Lise Sofie H Nissen-Meyer"

12 Publications

  • Page 1 of 1

The story of an extraordinary year: Challenges and opportunities in responding to Covid-19.

Transfus Apher Sci 2021 Apr 16;60(2):103092. Epub 2021 Feb 16.

Department of Infectious Medicine, Oslo University Hospital, Oslo, Norway.

Little more than a year after the first reports of a new coronavirus in Wuhan, China, the world is in the middle of a pandemic that has brought dramatic changes in societies all over the world. This is our story, as seen from the Department of Immunology and Transfusion at Oslo University Hospital (OUH).
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http://dx.doi.org/10.1016/j.transci.2021.103092DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7885672PMC
April 2021

HLA class I depletion by citric acid, and irradiation of apheresis platelets for transfusion of refractory patients.

Transfusion 2021 Apr 13;61(4):1222-1234. Epub 2021 Feb 13.

Department of Immunology and Transfusion Medicine, Oslo University Hospital, Oslo, Norway.

Background: Patients can form antibodies to foreign human leukocyte antigen (HLA) Class I antigens after exposure to allogeneic cells. These anti-HLA class I antibodies can bind transfused platelets (PLTs) and mediate their destruction, thus leading to PLT refractoriness. Patients with PLT refractoriness need HLA-matched PLTs, which require expensive HLA typing of donors, antibody analyses of patient sera and/or crossmatching. An alternative approach is to reduce PLT HLA Class I expression using a brief incubation in citric acid on ice at low pH.

Methods And Materials: Apheresis PLT concentrates were depleted of HLA Class I complexes by 5 minutes incubation in ice-cold citric acid, at pH 3.0. Surface expression of HLA Class I complexes, CD62P, CD63, phosphatidylserine, and complement factor C3c was analyzed by flow cytometry. PLT functionality was tested by thromboelastography (TEG).

Results: Acid treatment reduced the expression of HLA Class I complexes by 71% and potential for C3c binding by 11.5-fold compared to untreated PLTs. Acid-treated PLTs were significantly more activated than untreated PLTs, but irrespective of this increase in steady-state activation, CD62P and CD63 were strongly upregulated on both acid-treated and untreated PLTs after stimulation with thrombin receptor agonist peptide. Acid treatment did not induce apoptosis over time. X-ray irradiation did not significantly influence the expression of HLA Class I complexes, CD62P, CD63, and TEG variables on acid treated PLTs.

Conclusion: The relatively simple acid stripping method can be used with irradiated apheresis PLTs and may prevent transfusion-associated HLA sensitization and overcome PLT refractoriness.
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http://dx.doi.org/10.1111/trf.16282DOI Listing
April 2021

Differential Levels and Phosphorylation of Type 1 Inositol 1,4,5-Trisphosphate Receptor in Four Different Murine Models of Huntington Disease.

J Huntingtons Dis 2019 ;8(3):271-289

The Biotechnology Centre of Oslo, University of Oslo, Oslo, Norway.

Background: The intracellular ion channel type 1 inositol 1,4,5-trisphosphate receptor (IP3R1) releases Ca2+ from the endoplasmic reticulum upon stimulation with IP3. Perturbation of IP3R1 has been implicated in the development of several neurodegenerative disorders, including Huntington disease (HD).

Objective: To elucidate the putative role of IP3R1 phosphorylation in HD, we investigated IP3R1 levels and protein phosphorylation state in the striatum, hippocampus and cerebellum of four murine HD models.

Methods: Quantitative immunoblotting with antibodies to IP3R1 protein and its phosphorylated serines 1589 and 1755 was applied to brain homogenates from R6/1 mice to study early-onset aggressive HD. To determine if IP3R1 changes precede overt pathology, we immunostained tissues from the regions of interest and several control regions for IP3R1 in tgHDCAG51n rats and BACHD and zQ175DNKI mice, all recognized models for late-onset HD.

Results: R6/1 mice had reduced total IP3R1 immunoreactivity, variably reduced serine1755-phosphorylation in all regions investigated, and reduced serine1589-phosphorylation in cerebellum. IP3R1 levels were decreased relative to cell-specific marker proteins. In tgHDCAG51n rats we found reduced IP3R1 levels in the cerebellum, but otherwise unchanged IP3R1 phosphorylation and protein levels. In BACHD and zQ175DNKI mice only age-dependent decline of IP3R1 was observed.

Conclusion: The level and phosphorylation of IP3R1 is reduced to a variable degree in the different HD models relative to control, indicating that earlier findings in more aggressive exon 1-truncated HD models may not be replicated in models with higher construct validity. Further analysis of possible coupling of reduced IP3R1 levels with development of neuropathological responses and cell-specific degeneration is warranted.
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http://dx.doi.org/10.3233/JHD-180301DOI Listing
July 2020

Donor health assessment - When is blood donation safe?

Transfus Apher Sci 2019 Feb 31;58(1):113-116. Epub 2018 Dec 31.

International Consultancy in Blood Components Quality/Safety Improvement and DDR Strategies, London, United Kingdom.

Blood donation is a highly regulated practice in the world, ensuring the safety and efficacy of collected blood and its components whether used as irreplaceable parts of modern transfusion medicine, as a therapeutic modality or additional support to other clinical therapies. In Norway blood donation is regulated by governmental regulations ("Blodforskriften") and further instructed by national guidelines, "Veileder for transfusjonstjenesten" [1], providing an aid for assessment of donor health. This concise review touches upon: definitions of donor health and disease; some important pitfalls; and the handling of some common and less common pathophysiological conditions; with an example from the Blood center of Oslo University Hospital, Norway's largest blood center. I also comment on some medications used by a number of blood donors, although wounds, ulcers and surgery are not included. Considering the panorama of conditions blood donors can suffer from, blood donation can never be completely safe for everybody, as zero risk does not exist, but it is our task through donor evaluation to identify and reduce risk as much as possible.
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http://dx.doi.org/10.1016/j.transci.2018.12.016DOI Listing
February 2019

Corrigendum: Protein Kinase C Phosphorylates the System N Glutamine Transporter SN1 (Slc38a3) and Regulates Its Membrane Trafficking and Degradation.

Front Endocrinol (Lausanne) 2017 17;8:190. Epub 2017 Aug 17.

The Biotechnology Centre, University of Oslo, Oslo, Norway.

[This corrects the article on p. 138 in vol. 4, PMID: 24106489.].
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http://dx.doi.org/10.3389/fendo.2017.00190DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5562689PMC
August 2017

Paroxysmal nocturnal haemoglobinuria at Oslo University Hospital 2000-2010.

Tidsskr Nor Laegeforen 2015 Jun 16;135(11):1039-43. Epub 2015 Jun 16.

Avdeling for immunologi og transfusjonsmedisin Oslo universitetssykehus.

Background: Paroxysmal nocturnal haemoglobinuria (PNH) is a rare haematological disease characterised by chronic haemolysis, pancytopenia and venous thrombosis. The condition is attributable to a lack of control of complement attack on erythrocytes, thrombocytes and leukocytes, and can be diagnosed by means of flow cytometry. In this quality assurance study, we have reviewed information from the medical records of all patients tested for PNH using flow cytometry at our laboratory over a ten-year period.

Material And Method: In the period 2000-2010 a total of 28 patients were tested for PNH using flow cytometry at the Department of Immunology and Transfusion Medicine, Oslo University Hospital. We have reviewed the results of these examinations retrospectively together with information from medical records and transfusion data for the patients concerned.

Results: Flow cytometry identified 22 patients with PNH: four with classic disease and 18 with PNH secondary to another bone marrow disease. Five patients had atypical thrombosis. Seventeen patients received antithymocyte globulin or drug treatment; of these, six recovered from their bone marrow disease, while six died and five had a need for long-term transfusion. Five patients with life-threatening bone marrow disease underwent allogeneic stem cell transplantation, three of whom died. Six of 22 patients received eculizumab; the need for transfusion has been reduced or eliminated in three patients treated with eculizumab over a longer period.

Interpretation: Flow cytometry identified PNH in a majority of patients from whom we obtained samples. Most patients had a PNH clone secondary to bone marrow failure. Atypical thrombosis should be borne in mind as an indication for the test. Treatment with eculizumab is relevant for selected patients with PNH.
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http://dx.doi.org/10.4045/tidsskr.14.0444DOI Listing
June 2015

Protein Kinase C Phosphorylates the System N Glutamine Transporter SN1 (Slc38a3) and Regulates Its Membrane Trafficking and Degradation.

Front Endocrinol (Lausanne) 2013 Oct 2;4:138. Epub 2013 Oct 2.

The Biotechnology Centre, University of Oslo , Oslo , Norway ; The Institute of Basic Medical Sciences, University of Oslo , Oslo , Norway.

The system N transporter SN1 (also known as SNAT3) is enriched on perisynaptic astroglial cell membranes. SN1 mediates electroneutral and bidirectional glutamine transport, and regulates the intracellular as well as the extracellular concentrations of glutamine. We hypothesize that SN1 participates in the glutamate/γ-aminobutyric acid (GABA)-glutamine cycle and regulates the amount of glutamine supplied to the neurons for replenishment of the neurotransmitter pools of glutamate and GABA. We also hypothesize that its activity on the plasma membrane is regulated by protein kinase C (PKC)-mediated phosphorylation and that SN1 activity has an impact on synaptic plasticity. This review discusses reports on the regulation of SN1 by PKC and presents a consolidated model for regulation and degradation of SN1 and the subsequent functional implications. As SN1 function is likely also regulated by PKC-mediated phosphorylation in peripheral organs, the same mechanisms may, thus, have impact on e.g., pH regulation in the kidney, urea formation in the liver, and insulin secretion in the pancreas.
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http://dx.doi.org/10.3389/fendo.2013.00138DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3788335PMC
October 2013

Protein kinase C-mediated phosphorylation of a single serine residue on the rat glial glutamine transporter SN1 governs its membrane trafficking.

J Neurosci 2011 Apr;31(17):6565-75

The Biotechnology Centre and Centre for Molecular Biology and Neuroscience, University of Oslo, N-0317 Oslo, Norway.

Molecular mechanisms involved in the replenishment of the fast neurotransmitters glutamate and GABA are poorly understood. Glutamine sustains their generation. However, glutamine formation from the recycled transmitters is confined to glial processes and requires facilitators for its translocation across the glial and neuronal membranes. Indeed, glial processes are enriched with the system N transporter SN1 (Slc38a3), which, by bidirectional transport, maintains steady extracellular glutamine levels and thereby furnishes neurons with the primary precursor for fast neurotransmitters. We now demonstrate that SN1 is phosphorylated by protein kinase Cα (PKCα) and PKCγ. Electrophysiological characterization shows that phosphorylation reduces V(max) dramatically, whereas no significant effects are seen on the K(m). Phosphorylation occurs specifically at a single serine residue (S52) in the N-terminal rat (Rattus norvegicus) SN1 and results in sequestration of the protein into intracellular reservoirs. Prolonged activation of PKC results in partial degradation of SN1. These results provide the first demonstration of phosphorylation of SN1 and regulation of its activity at the plasma membrane. Interestingly, membrane trafficking of SN1 resembles that of the glutamate transporter GLT and the glutamate-aspartate transporter GLAST: it involves the same PKC isoforms and occurs in the same glial processes. This suggests that the glutamate/GABA-glutamine cycle may be modified at two key points by similar signaling events and unmasks a prominent role for PKC-dependent phosphorylation. Our data suggest that extracellular glutamine levels may be fine-tuned by dynamic regulation of glial SN1 activity, which may impact on transmitter generation, contribute to defining quantal size, and have profound effects on synaptic plasticity.
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http://dx.doi.org/10.1523/JNEUROSCI.3694-10.2011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6622677PMC
April 2011

Calmodulin-dependent kinase 1beta is expressed in the epiphyseal growth plate and regulates proliferation of mouse calvarial osteoblasts in vitro.

Bone 2008 Oct 20;43(4):700-7. Epub 2008 Jun 20.

Institute of Basic Medical Sciences, Department of Biochemistry, University of Oslo, Oslo, Norway.

The Ca(2+)/Calmodulin-dependent protein kinase (CaMK) family is activated in response to elevation of intracellular Ca(2+), and includes CaMK1 (as well as CaMK2 and CaMK4), which exists as different isoforms (alpha, beta, gamma and delta). CaMK1 is present in several cell types and may be involved in various cellular processes, but its role in bone is unknown. In situ hybridization was used to determine the spatial and temporal expression of CaMK1beta during endochondral bone development in mouse embryos and newborn pups. The cellular and subcellular distribution of CaMK1 was assessed by quantitative immunogold electron microscopy (EM). The role of CaMK1beta in mouse calvarial osteoblasts was investigated by using small interfering RNA (siRNA) to silence its expression, while in parallel monitoring cell proliferation and levels of skeletogenic transcripts. cRNA in situ hybridization and EM studies show that CaMK1beta is mainly located in developing long bones and vertebrae (from ED14.5 until day 10 after birth), with highest expression in epiphyseal growth plate hypertrophic chondrocytes. By RT-PCR, we show that CaMK1beta2 (but not beta1) is expressed in mouse hind limbs (in vivo) and mouse calvarial osteoblasts (in vitro), and also in primary human articular chondrocyte cultures. Silencing of CaMK1beta in mouse calvarial osteoblasts by siRNA significantly decreases osteoblast proliferation and c-Fos gene expression (approx. 50%), without affecting skeletogenic markers for more differentiated osteoblasts (i.e. Cbfa1/Runx2, Osterix (Osx), Osteocalcin (Oc), Alkaline phosphatase (Alp) and Osteopontin (Opn)). These results identify CaMK1beta as a novel regulator of osteoblast proliferation, via mechanisms that may at least in part involve c-Fos, thus implicating CaMK1beta in the regulation of bone and cartilage development.
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http://dx.doi.org/10.1016/j.bone.2008.06.006DOI Listing
October 2008

How can antiepileptic drugs affect bone mass, structure and metabolism? Lessons from animal studies.

Seizure 2008 Mar 3;17(2):187-91. Epub 2008 Jan 3.

Department of Biochemistry, Institute of Basic Medical Sciences, University of Oslo, Norway.

Patients with epilepsy, treated with antiepileptic drugs (AEDs) are at increased risk of fractures. Although several commonly used AEDs reduce bone mass in patients, the mechanisms are only scarcely known. In this review, we focus on the usefulness of animal models to explore the skeletal effects of AEDs. Moreover, we report our findings from a recent study comparing the effect of levetiracetam (LEV), phenytoin (PHT) and valproate (VPA) on various aspects of bone health in actively growing female rats. Our data indicate that these AEDs act differently on bone mass, structure and metabolism. A novel finding is that LEV reduces bone strength and bone formation without altering bone mass. Based on these results we propose that epidemiological fracture studies of patients treated with LEV are needed, and that these patients should be evaluated regularly to identify possible bone-related side effects.
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http://dx.doi.org/10.1016/j.seizure.2007.11.024DOI Listing
March 2008

Levetiracetam, phenytoin, and valproate act differently on rat bone mass, structure, and metabolism.

Epilepsia 2007 Oct 18;48(10):1850-60. Epub 2007 Jul 18.

Department of Biochemistry, Institute of Basic Medical Sciences, University of Oslo, Norway.

Purpose: Long-term treatment with antiepileptic drugs (AEDs) is associated with increased risk of fractures. Phenytoin (PHT) and valproate (VPA) have both been suggested to influence bone health, whereas levetiracetam (LEV) is scarcely studied. The present study compares the effect of these AEDs on bone mass, biomechanical strength, and bone turnover in rats.

Methods: Female rats received PHT (50 mg/kg), VPA (300 mg/kg), or LEV (50 and 150 mg/kg) for 90 days. Dissected femurs were analyzed using dual energy x-ray absorptiometry (DXA), three-point cantilever bending, and histomorphological evaluation. Serum levels of biochemical bone turnover markers were monitored using immunoassay quantification.

Results: PHT and VPA reduced bone mineral density (BMD) and content (BMC) in one or more bone compartments, whereas LEV did not. VPA induced increased bone turnover, whereas modest changes were observed for PHT. Interestingly, low-dose LEV was associated with reduced biomechanical strength of the femoral neck (mainly trabecular bone). In addition, low-dose LEV treatment resulted in significantly reduced levels of serum osteocalcin, a marker of bone formation. Histomorphological analyses indicated increased retention of cartilage remnants at the growth plate metaphysis of rats treated with low-dose LEV vs. controls.

Conclusions: PHT, VPA, and LEV exert differential effects on bone mass and strength, suggesting different mechanisms of action. The weakening effect of low-dose LEV on the femoral neck, despite a constant BMD, suggests a primary effect on bone quality. These findings warrant further human studies of possible adverse effects of LEV on bone development and growth, particularly in children and adolescents.
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http://dx.doi.org/10.1111/j.1528-1167.2007.01176.xDOI Listing
October 2007