Publications by authors named "Lefvert A"

Background: Dendritic cells (DCs) initiate immune responses through their direct interaction with effector cells. However, the mechanism by which DC activity is regulated is not well defined. Previous studies have shown that CTLA4 on T cells regulates DCs function by "cross-talk".

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Objective: Measurement of inflammatory mediators is an important tool to assess inflammation. We have, therefore, conducted a survey within the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study to evaluate the inter-relationship between soluble CTLA-4 (sCTLA-4) and other inflammatory markers.

Materials And Methods: This is a population-based study, designed to quantify the circulating serum levels of sCTLA-4 and other inflammatory markers such as CRP and pro-inflammatory cytokines and chemokines by in-house ELISA, Immuno-turbidimetry and multiplex ELISA, respectively.

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  • The study investigates the genetic link between the PDCD1 gene and Wegener's granulomatosis (WG), a type of autoimmune disorder.
  • The researchers analyzed three specific SNPs in the PDCD1 gene among patients with WG and healthy controls, using methods like genotyping and ELISA.
  • Ultimately, they found no significant association of the PDCD1 SNPs with WG, indicating that these genetic factors may not play a role in the disease.
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  • Myasthenia gravis (MG) is an autoimmune disorder that causes muscle weakness due to autoantibodies targeting acetylcholine receptors, and CTLA-4 is implicated in its immune response.
  • Researchers identified two new isoforms of CTLA-4 mRNA through alternative splicing in peripheral blood mononuclear cells (PBMCs) from MG patients.
  • The study found reduced levels of soluble CTLA-4 mRNA in MG patients compared to healthy individuals, suggesting a unique mRNA expression pattern that warrants further investigation into how alternative splicing affects the disease.
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  • A study was conducted to explore the role of the PTPN22 R620W gene variant in myasthenia gravis (MG), involving 409 MG patients and 1557 controls from Sweden.
  • The W620 variant was found to be significantly more common in MG patients, with an odds ratio of 1.52, indicating a potential link to the disease.
  • Further tests on patient-derived cells showed that W620 carriers had increased production of anti-AChR antibodies and IL-2 when exposed to acetylcholine receptors, suggesting that this variant may impair immune function in the context of MG.
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Objectives: The molecular mechanisms underlying the regulation of the CD152 (CTLA-4) gene are largely unknown. Two single nucleotide polymorphisms (SNPs) located in the promoter region are suspected to contribute to the pathogenesis of myasthenia gravis (MG) through regulation of gene expression. SETTING, SUBJECTS AND DESIGN: One hundred and sixty-five unrelated Swedish-Caucasian patients with MG (103 females and 62 males, age 17 to 92 years) and 148 ethnically matched healthy individuals were studied.

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  • An investigation into the role of the inhibitory receptor Programmed Death-1 (PD-1) in 273 patients with autoimmune myasthenia gravis revealed no significant genetic association with the disease through SNP genotyping.
  • Gene expression levels in patients did not differ from those in healthy controls.
  • However, there were higher levels of PD-1 on T cells and its ligand PD-L1 on monocytes in patients, indicating a potential natural regulatory role for PD-1 in myasthenia gravis.
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CD80 is a costimulatory factor mainly expressed on the surface of activated monocytes, B cells and dendritic cells. In this study, we demonstrate that 24% of healthy individuals have soluble forms of CD80, sCD80, in their serum. The concentration of sCD80 ranged from 0 to 1 mg/l.

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Certain alleles of cytokine genes interleukin-1 beta (IL-1beta), interleukin-1 receptor antagonist (IL-1Ra), and tumor necrosis factor alpha (TNF-alpha) are correlated with increased production of the proteins. The aim of this study was to investigate polymorphisms of these genes and their possible correlation with the development of stroke. This matched case-control study was nested within the population-based Västerbotten Intervention Program (VIP) cohort and the Northern Sweden World Health Organization MONICA (Multinational Monitoring of Trends and Determinants in Cardiovascular Diseases) cohort, based on individuals who were free from cardiovascular events when the cohorts were established.

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Objectives: To measure clinical and immunological parameters in a patient with myasthenia gravis (MG) treated with antibodies against CD25 (basiliximab, Simulect). Patient and methods - Injections of basiliximab were given repeatedly together with cyclosporin A and corticosteroids for 9 months to a patient with severe MG. Her muscle function score was monitored and the immunological parameters were followed using ELISA, flow cytometry and radioimmunoassay.

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Objective: The T cell co-stimulatory factors CD28 and CTLA-4 and their ligands CD80 and CD86 occur as receptors on T cells and antigen-presenting cells and also in soluble forms in the circulation. We determined the levels of soluble co-stimulatory molecules in patients with abdominal aortic aneurysm (AAA) and normal individuals. We further correlated these soluble co-stimulatory molecules to other clinical parameters of importance such as age of the patient, presence of hypertension, size of the aneurysm and levels of matrix metalloproteinases-9 and C-reactive protein.

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Objectives: To measure clinical and immunological parameters in a patient with myasthenia gravis (MG) treated with antibodies against tumour necrosis factor-alpha (infliximab, Remicade).

Patient And Methods: A patient with severe MG received repeated injections of infliximab. His muscle function score was monitored and the immunological parameters were followed using enzyme-linked immunosorbent assay, flow cytometry and radioimmunoassay.

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Background: Myasthenia gravis (MG) is an autoimmune disorder of neuromuscular transmission. The majority of patients show abnormal thymic histology.

Setting: The study was performed at the Myasthenia Gravis Centre, Karolinska University Hospital, and at the Immunological Research Laboratory, Centre for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.

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The costimulatory factors CD28, CD80, CD86 and CD152 needed to start and turn off an immune response are present as membrane receptors and soluble proteins. There was no difference in the serum levels of soluble costimulatory molecules in 153 healthy controls and 118 patients with myasthenia gravis. However, we could confirm that the soluble forms of ICAM-1 and CD25 were increased in patients.

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Objectives: To describe two patients with myasthenia gravis (MG) and prolactinoma and analyze the associations between MG and prolactin (PRL) levels.

Design: Two case reports and a case-control study of PRL levels in 192 patients with MG.

Participants: The Immunological Research Laboratory, Center for Molecular Medicine, Department of Medicine and the Department of Neurology, Karolinska Institutet, Stockholm, Sweden; St Petersburg Medical Academy for Postgraduate Studies, and St Petersburg State Medical Pediatric Academy, Russia.

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The HLA class I/II alleles and the tumor necrosis factor alpha (TNFA) locus are closely linked in the MHC complex. We have characterized the causative factor VIII mutation, HLA alleles as well as 4 polymorphisms (-827C>T, -308G>A, -238A>G, and 670A>G) in the TNFA gene in 164 patients (124 severe, 26 moderate, and 14 mild) in 78 families with hemophilia A enrolled in the Malmö International Brother Study (MIBS). Inhibitors were identified in 77.

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Objectives: Wegener's granulomatosis (WG) is a chronic inflammatory disease characterized by granulomatosis inflammation, systemic vasculitis and glomerulonephritis. In patients, the peripheral T cells are characterized by mono/oligoclonal CD4+/CD8+ T-cell AV/BV receptor expansions, with aberrant expression of activation markers. This study was designed to characterize the phenotypic differences between the expanded and nonexpanded T-cell populations.

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Article Synopsis
  • The study investigates the presence of autoantibodies against stress-related neurohormones in individuals with aggressive behavior, such as those with conduct disorder and violent prisoners.
  • Results show significantly elevated levels of ACTH-reactive autoantibodies in these aggressive groups compared to healthy controls, indicating a possible link to altered stress responses.
  • The findings suggest that these autoantibodies may disrupt neuroendocrine functions related to stress and behavior, pointing to a biological mechanism behind human aggression.
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Inhibitory regulatory functions of B7-H3 and B7-H4 regarding T-cell activation have been reported recently. Little is known about the significance of human B7-H3 and B7-H4 expression in non-small-cell lung cancer (NSCLC), and we conducted the present study to address this issue in cell lines and tumor tissue from 70 patients. B7-H3 is over-expressed by all six NSCLC cell lines on both mRNA and protein level.

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The aim of the Malmö International Brother Study (MIBS) is to evaluate host genetic factors associated with the development of inhibitory antibodies in patients with hemophilia. Factor VIII gene mutations and genetic polymorphisms of the IL1beta, IL4, and IL10 genes, known to influence antibody production in autoimmune diseases, were analyzed in 164 patients (124 with severe, 26 with moderate, and 14 with mild disease) in 78 unrelated families with hemophilia A. Seventy-seven (47%) patients in 54 families had a history of inhibitors (57 high responding, 20 low responding).

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Myasthenia gravis (MG) is commonly regarded as the prototype of an antibody-mediated, organ-specific autoimmune disease. Antibodies against the acetylcholine receptor (AChR) on the muscle endplate trigger its typical clinical manifestations of weakness and fatiguability. T-B cell interactions are thought to play a crucial role in the pathogenesis of MG.

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Previously, we identified that a majority of patients with anorexia nervosa (AN) and bulimia nervosa (BN) as well as some control subjects display autoantibodies (autoAbs) reacting with alpha-melanocyte-stimulating hormone (alpha-MSH) or adrenocorticotropic hormone, melanocortin peptides involved in appetite control and the stress response. In this work, we studied the relevance of such autoAbs to AN and BN. In addition to previously identified neuropeptide autoAbs, the current study revealed the presence of autoAbs reacting with oxytocin (OT) or vasopressin (VP) in both patients and controls.

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The beta2-adrenergic receptor (beta2-AR) belongs to the group of G-protein-coupled receptors and is present on skeletal and cardiac muscle cells and on lymphocytes. The gene encoding beta2-AR (ADRB2) displays a moderate degree of heterogeneity in the human population and the distributions of single-nucleotide polymorphisms (SNPs) at amino acid positions 16, 27, and 164 are changed in asthma, obesity, and hypertension and in the autoimmune disease myasthenia gravis. An involvement of the beta2-AR has also been suggested in human rheumatoid arthritis (RA) and its animal model.

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