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Dive into the research topics where Sven Björnsson is active.

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Featured researches published by Sven Björnsson.


Biochimica et Biophysica Acta | 1998

Differential expressions of mRNA for proteoglycans, collagens and transforming growth factor-beta in the human cervix during pregnancy and involution.

Gunilla Westergren-Thorsson; Margareta Norman; Sven Björnsson; Urszula Endrésen; Ylva Vladic Stjernholm; Gunvor Ekman; Anders Malmström

During pregnancy and involution, an extensive remodelling of the human cervical connective tissue occurs. This cervical ripening is one of the most pronounced physiological remodelling processes known in human connective tissue. To investigate how the remodelling is accomplished, the levels of mRNA for collagen I and III, versican and three small proteoglycans, biglycan, decorin and fibromodulin, were evaluated using Northern blots at different stages of cervical ripening. In the corresponding biopsies the concentration of collagen and of small and large proteoglycans were determined. The role of transforming growth factor-beta (TGF-beta) as a mediator of the remodelling process was also investigated. The concentration of collagen decreased and 1 week before partus, 50% of the nonpregnant level was attained. No further decrease was noted after partus. The mRNA for collagen I and III did, however, not decrease in the term pregnant cervix 1 week before partus. Only 20-30% decrease during the final ripening just before partus was recorded. Neither did the mRNA levels of the small proteoglycans change significantly during the ripening, despite an almost 50% decrease in the concentration of the small proteoglycans. The message for versican was, however, 5-fold increased at partus and then gradually returned to nonpregnant levels within 4 days after delivery. These changes corresponded to similar changes in the concentration of the large proteoglycan. Thus, the remodelling of the cervical connective tissue is achieved by two different mechanisms, on one hand an increased turnover of collagen and the small proteoglycans, on the other a changed transcription followed by an increased production of versican. During the involution 2- to 3-fold increases in the messages for collagen I and III, and the small proteoglycans, biglycan and decorin, corresponded to increases in the concentration of the small proteoglycans and non-extractable collagen. The message for TGF-beta was increased 2-fold immediately after delivery compared with the term pregnant state. Thus, TGF-beta may be of importance for the reconstruction of the cervix, which starts immediately after partus.


Respiratory Research | 2007

Expression of Toll-like receptor 9 in nose, peripheral blood and bone marrow during symptomatic allergic rhinitis.

Mattias Fransson; Mikael Benson; Jonas Erjefält; Lennart Jansson; Rolf Uddman; Sven Björnsson; Lars-Olaf Cardell; Mikael Adner

BackgroundAllergic rhinitis is an inflammatory disease of the upper airway mucosa that also affects leukocytes in bone marrow and peripheral blood. Toll-like receptor 9 (TLR9) is a receptor for unmethylated CpG dinucleotides found in bacterial and viral DNA. The present study was designed to examine the expression of TLR9 in the nasal mucosa and in leukocytes derived from different cellular compartments during symptomatic allergic rhinitis.MethodsThe study was based on 32 patients with seasonal allergic rhinitis and 18 healthy subjects, serving as controls. Nasal biopsies were obtained before and after allergen challenge. Bone marrow, peripheral blood and nasal lavage fluid were sampled outside and during pollen season. The expression of TLR9 in tissues and cells was analyzed using immunohistochemistry and flow cytometry, respectively.ResultsTLR9 was found in several cell types in the nasal mucosa and in different leukocyte subpopulations derived from bone marrow, peripheral blood and nasal lavage fluid. The leukocyte expression was generally higher in bone marrow than in peripheral blood, and not affected by symptomatic allergic rhinitis.ConclusionThe widespread expression of TLR9 in the nasal mucosa along with its rich representation in leukocytes in different compartments, demonstrate the possibility for cells involved in allergic airway inflammation to directly interact with bacterial and viral DNA.


PLOS ONE | 2012

The Activation Pattern of Blood Leukocytes in Head and Neck Squamous Cell Carcinoma Is Correlated to Survival

Camilla Rydberg Millrud; Anne Månsson Kvarnhammar; Rolf Uddman; Sven Björnsson; Kristian Riesbeck; Lars-Olaf Cardell

Head and neck squamous cell carcinoma (HNSCC) is known to cause substantial immunosuppression. The present study was designed to characterize blood leukocyte activation in HNSCC and to investigate if the individual activation pattern could be related to tumor progress and survival. The leukocyte activation profile of HNSCC patients and healthy controls was assessed with flow cytometry. HNSCC patients displayed increased numbers of monocytes, neutrophils and total leukocytes as well as an enhanced neutrophil/lymphocyte ratio. In addition, patients had a higher percentage of CD69+, CD71+ and CD98+ T cell subsets and NK cells, and a reduced expression of L-selectin in CD14highCD16+ monocytes and neutrophils, when compared to controls. These changes could be correlated to both tumor burden and spread to lymph nodes. Among the cancer patients an increased neutrophil/lymphocyte ratio, a low neutrophil and CD14high CD16+ monocyte activation state and an elevated CD4/CD8 ratio were related to poor survival. In contrast, a high percentage of CD98+ Th cells appeared to be associated with a better outcome. Taken together, the present data indicate that HNSCC causes activation of blood leukocytes and that the individual activation pattern can be linked to prognosis.


International Archives of Allergy and Immunology | 2010

TLR3 in Human Eosinophils: Functional Effects and Decreased Expression during Allergic Rhinitis

Anne Månsson; Mattias Fransson; Mikael Adner; Mikael Benson; Rolf Uddman; Sven Björnsson; Lars-Olaf Cardell

Background/Aim: Viral respiratory infections are increasingly implicated in allergic exacerbations. Virus-induced activation of eosinophils through Toll-like receptors (TLRs) could be involved. The present study was designed to examine TLR3 expression in eosinophils from bone marrow (BM) and peripheral blood (PB) during symptomatic allergic rhinitis, and to evaluate the functional responsiveness of TLR3 in purified eosinophils. Methods: BM and PB samples were obtained from healthy volunteers and patients with seasonal allergic rhinitis outside and during the pollen season. Eosinophils were analyzed for TLR3 expression by flow cytometry. Polyinosinic:polycytidylic acid [poly(I:C)], an agonist for TLR3, was used to assess its functional role in purified eosinophils and the intracellular signaling pathways involved. Results: TLR3 expression was demonstrated in BM and PB eosinophils. It was higher in BM-derived than in circulating cells and it was downregulated in both compartments during symptomatic allergic rhinitis. TLR3 expression was also downregulated in the presence of interleukin (IL)-4 and IL- 5. Stimulation with poly(I:C) increased the percentage of CD11b+ cells and enhanced the secretion of IL-8, effects mediated via the p38 mitogen-activated protein kinases and nuclear factor-ĸB signaling pathways. Moreover, pretreatment with IL-5 augmented the poly(I:C)-induced IL-8 release. Conclusions: Eosinophils activated via TLR3 might be more able to home and recruit leukocytes to sites of inflammation. The decreased TLR3 expression during symptomatic allergic rhinitis and in the presence of Th2 cytokines indicates a role in allergic airway inflammation. Thus, eosinophils might function as a link between viral infections and exacerbations of allergic disease.


Analytical Biochemistry | 1982

Zonal rate centrifugation of proteoglycans in sucrose gradients

Ahnders Franzén; Sven Björnsson; Dick Heinegård

Sensitive detection of proteoglycan and protein in concentrated sucrose solutions is obtained by measuring the absorbance at 206 nm. This method for detection has been used to study conditions affecting zonal rate sedimentation of proteoglycans and proteins in sucrose gradients. The ionic environment in the gradients markedly affects the sedimentation rate of the polyanionic proteoglycans and fragments thereof, while proteins sediment at an approximately constant rate irrespective of the ionic strength. The procedure can be used to separate proteoglycan aggregates from monomers and to determine size distributions of the compounds. In separate experiments, intact and fragmented proteoglycans are separated from proteins.


Analytical Biochemistry | 2002

Quantitation of repetitive epitopes in glycosaminoglycans immobilized on hydrophobic membranes treated with cationic detergents

Madeleine Rosén; Inger Edfors-Lilja; Sven Björnsson

Glycosaminoglycans (GAGs) are linear carbohydrate polymers containing repetitive sequences of differently sulfated uronic acid and glycosamine residues that are recognized by antibodies raised against proteoglycans. We have developed a method to demonstrate such repetitive sequence motifs in isolated GAG chains immobilized on hydrophobic membranes derivatized with cationic detergents. Six monoclonal antibodies directed against Cs (2B6, 3B3, Cs56, and 1B5), Hs (HepSS), and Ks (5D4) were used to detect native and chondroitinase-generated epitopes in the immobilized GAGs. All antibodies, except 1B5, were able to detect epitopes in both proteoglycans and isolated GAGs. Type of detergent and buffer composition affected the accessibility and the retention of immobilized GAGs. The epitope density, i.e., the number of repetitive epitopes per GAG mass, was estimated as the ratio between antibody (epitope) and Alcian blue (mass) staining measured simultaneously. The epitope profiles, using six antibodies, were different for each sample (CsA, CsC, Ds, Hs, intact cartilage, and human serum). The epitope profile may be used as a structural characteristic of a GAG population. Electrophoretic separation of GAGs based on their glucuronic/ioduronic acid content and O-sulfate/N-sulfate ratio was performed using a diethylene glycol-diaminobutanol agarose gel. The electrophoretic populations were characterized by immunoblotting to detergent-treated membranes.


Analytical Biochemistry | 1998

Quantitation of Proteoglycans as Glycosaminoglycans in Biological Fluids Using an Alcian Blue Dot Blot Analysis

Sven Björnsson


Analytical Biochemistry | 2000

Binding and detection of glycosaminoglycans immobilized on membranes treated with cationic detergents.

Madeleine Karlsson; Inger Edfors-Lilja; Sven Björnsson


Methods of Molecular Biology | 2001

Quantitation of Proteoglycans in Biological Fluids Using Alcian Blue

Madeleine Karlsson; Sven Björnsson


Journal of Investigational Allergology and Clinical Immunology | 2010

Leukocyte phenotype changes induced by specific immunotherapy in patients with birch allergy.

Anne Månsson; Ofir Bachar; Mikael Adner; Sven Björnsson; Lars-Olaf Cardell

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Lars-Olaf Cardell

Karolinska University Hospital

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Inger Edfors-Lilja

Swedish University of Agricultural Sciences

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