35 research outputs found

    Osteoporosis in experimental postmenopausal polyarthritis: the relative contributions of estrogen deficiency and inflammation

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    Generalized osteoporosis in postmenopausal rheumatoid arthritis (RA) is caused both by estrogen deficiency and by the inflammatory disease. The relative importance of each of these factors is unknown. The aim of this study was to establish a murine model of osteoporosis in postmenopausal RA, and to evaluate the relative importance and mechanisms of menopause and arthritis-related osteoporosis. To mimic postmenopausal RA, DBA/1 mice were ovariectomized, followed by the induction of type II collagen-induced arthritis. After the mice had been killed, paws were collected for histology, one femur for bone mineral density (BMD) and sera for analyses of markers of bone resorption (RatLaps; type I collagen cross-links, bone formation (osteocalcin) and cartilage destruction (cartilage oligomeric matrix protein), and for the evaluation of antigen-specific and innate immune responsiveness. Ovariectomized mice displayed more severe arthritis than sham-operated controls. At termination of the experiment, arthritic control mice and non-arthritic ovariectomized mice displayed trabecular bone losses of 26% and 22%, respectively. Ovariectomized mice with arthritis had as much as 58% decrease in trabecular BMD. Interestingly, cortical BMD was decreased by arthritis but was not affected by hormonal status. In addition, markers of bone resorption and cartilage destruction were increased in arthritic mice, whereas markers of bone formation were increased in ovariectomized mice. This study demonstrates that the loss of endogenous estrogen and inflammation contribute additively and equally to osteoporosis in experimental postmenopausal polyarthritis. Markers of bone remodeling and bone marrow lymphocyte phenotypes indicate different mechanisms for the development of osteoporosis caused by ovariectomy and arthritis in this model

    IGF1R signalling is a guardian of self-tolerance restricting autoantibody production

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    Objective: Insulin-like growth factor 1 receptor (IGF1R) acts at the crossroad between immunity and cancer, being an attractive therapeutic target in these areas. IGF1R is broadly expressed by antigen-presenting cells (APC). Using mice immunised with the methylated albumin from bovine serum (BSA-immunised mice) and human CD14+ APCs, we investigated the role that IGF1R plays during adaptive immune responses. Methods: The mBSA-immunised mice were treated with synthetic inhibitor NT157 or short hairpin RNA to inhibit IGF1R signalling, and spleens were analysed by immunohistology and flow cytometry. The levels of autoantibody and cytokine production were measured by microarray or conventional ELISA. The transcriptional profile of CD14+ cells from blood of 55 patients with rheumatoid arthritis (RA) was analysed with RNA-sequencing. Results: Inhibition of IGF1R resulted in perifollicular infiltration of functionally compromised S256-phosphorylated FoxO1+ APCs, and an increased frequency of IgM+CD21+ B cells, which enlarged the marginal zone (MZ). Enlargement of MHCII+CD11b+ APCs ensured favourable conditions for their communication with IgM+ B cells in the MZ. The reduced expression of ICOSL and CXCR5 by APCs after IGF1R inhibition led to impaired T cell control, which resulted in autoreactivity of extra-follicular B cells and autoantibody production. In the clinical setting, the low expression of IGF1R on CD14+ APCs was associated with an involuted FOXO pathway, non-inflammatory cell metabolism and a high IL10 production characteristic for tolerogenic macrophages. Furthermore, autoantibody positivity was associated with low IGF1R signalling in CD14+ APCs. Conclusions: In experimental model and in patient material, this study demonstrates that IGF1R plays an important role in preventing autoimmunity. The study raises awareness of that immune tolerance may be broken during therapeutic IGF1R targeting

    Estren promotes androgen phenotypes in primary lymphoid organs and submandibular glands

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    BACKGROUND: Estrogens and androgens have extensive effects on the immune system, for example they suppress both T and B lymphopoiesis in thymus and bone marrow. Submandibular glands are sexually dimorphic in rodents, resulting in larger granular convoluted tubules in males compared to females. The aim of the present experiments was to investigate the estrogenic and androgenic effects of 4-estren-3α,17ÎČ-diol (estren) on thymus, bone marrow and submandibular glands, and compare the effects to those of 17ÎČ-estradiol (E2) and 5α-dihydrotestosterone (DHT), respectively. Estrogen receptors (ERs) were blocked by treatment of mice with the ER-antagonist ICI 182,780; also, knock-out mice lacking one or both ERs were used. RESULTS: As expected, the presence of functional ERs was mandatory for all the effects of E2. Similar to DHT-treatment, estren-treatment resulted in decreased thymus weight, as well as decreased frequency of bone marrow B cells. Treatment with estren or DHT also resulted in a shift in submandibular glands towards an androgen phenotype. All the effects of estren and DHT were independent of ERs. CONCLUSION: Our study is the first to show that estren has similar effects as the androgen DHT on lymphopoiesis in thymus and bone marrow, and on submandibular glands, and that these effects are independent of estrogen receptors. This supports the hypothesis of estren being able to signal through the androgen receptor

    Cohesin-Mediated Chromatin Interactions and Autoimmunity

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    Proper physiological functioning of any cell type requires ordered chromatin organization. In this context, cohesin complex performs important functions preventing premature separation of sister chromatids after DNA replication. In partnership with CCCTC-binding factor, it ensures insulator activity to organize enhancers and promoters within regulatory chromatin. Homozygous mutations and dysfunction of individual cohesin proteins are embryonically lethal in humans and mice, which limits in vivo research work to embryonic stem cells and progenitors. Conditional alleles of cohesin complex proteins have been generated to investigate their functional roles in greater detail at later developmental stages. Thus, genome regulation enabled by action of cohesin proteins is potentially crucial in lineage cell development, including immune homeostasis. In this review, we provide current knowledge on the role of cohesin complex in leukocyte maturation and adaptive immunity. Conditional knockout and shRNA-mediated inhibition of individual cohesin proteins in mice demonstrated their importance in haematopoiesis, adipogenesis and inflammation. Notably, these effects occur rather through changes in transcriptional gene regulation than through expected cell cycle defects. This positions cohesin at the crossroad of immune pathways including NF-kB, IL-6, and IFNÎł signaling. Cohesin proteins emerged as vital regulators at early developmental stages of thymocytes and B cells and after antigen challenge. Human genome-wide association studies are remarkably concordant with these findings and present associations between cohesin and rheumatoid arthritis, multiple sclerosis and HLA-B27 related chronic inflammatory conditions. Furthermore, bioinformatic prediction based on protein-protein interactions reveal a tight connection between the cohesin complex and immune relevant processes supporting the notion that cohesin will unearth new clues in regulation of autoimmunity

    Smoking Is Associated With Low Levels of Soluble PD-L1 in Rheumatoid Arthritis

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    BackgroundSmoking is a risk factor for developing rheumatoid arthritis (RA), but the mechanism remains uncertain. We previously demonstrated that smoking lowers the T cell activation threshold by limiting programmed death protein 1 (PD-1) expression.AimTo investigate how smoking influence the levels of soluble PD-1 ligand (sPD-L1).MethodSerum levels of sPD-L1 were measured in 246 RA patients and in 168 healthy subjects. The analysis was done with respect to inflammation, smoking, treatments, and autoantibody status. The effect of therapeutic TNF-inhibiting antibodies (TNFi) on sPD-L1 was studied in 16 RA patients at their first infliximab infusion. The expression of FcÎł-receptor (FcÎłR) subclass IIB and IIIA was analyzed with quantitative polymerase chain reaction in peripheral blood mononuclear cells (PBMCs) from 12 RA patients and 15 healthy controls, and in healthy PBMC exposed to IgG containing antibodies to cyclic citrullinated peptides (aCCP).ResultsThe negative association between smoking and sPD-L1 in RA patients was established by multiple logistic regression (OR = 0.52, p = 0.038). Other covariates in the regression model were serum levels of IL-1ÎČ representing inflammation (OR = 1.6, p = 0.0076) and aCCP positivity (OR = 1.9, p = 0.047). First infliximab infusion repressed sPD-L1 (p = 0.023) in patients, and low levels of sPD-L1 were found in patients with early RA treated with TNFi (p = 0.018). Treatment with TNFi was associated with higher sPD-L1 in patients with long disease duration (p = 0.041) and restored levels in smokers. In vitro exposure to aCCP+ IgG suppressed sPD-L1 (p = 0.036), but aCCP+ patients with long disease duration had higher sPD-L1 (p = 0.016). High ratio of the inhibitory FcÎłR subclass IIB over the stimulatory IIIA resulted in low sPD-L1 release (p = 0.029). Smoking was associated with a higher FcÎłR IIB/IIIA ratio (p = 0.00062) and lower levels of sPD-L1 (p = 0.013).ConclusionIn RA, serum sPD-L1 was related to systemic inflammation and aCCP positivity. Smoking altered the expression of FcÎłRs and limited sPD-L1 in RA patients, permitting inappropriate T cell responses. Differential regulation of sPD-L1 during the early and late RA may indicate transposition from acute to chronic inflammation

    Role of endogenous and exogenous female sex hormones in arthritis and osteoporosis development in B10.Q-ncf1*/* mice with collagen-induced chronic arthritis

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    <p>Abstract</p> <p>Background</p> <p>Collagen-induced arthritis (CIA) is an often-used murine model for human rheumatoid arthritis (RA). Earlier studies have shown potent anti-arthritic effects with the female sex hormone estradiol and the selective estrogen receptor modulator (SERM) raloxifene in CIA in DBA/1-mice. B10.Q-ncf1<sup>*/*</sup>mice are B10.Q mice with a mutated Ncf1 gene. In B10.Q-ncf1<sup>*/*</sup>mice, CIA develops as a chronic relapsing disease, which more accurately mimics human RA. We investigated the role of endogenous and exogenous sex steroids and raloxifene in the course of this model of chronic arthritis. We also examined whether treatment would prevent the development of inflammation-triggered generalized osteoporosis.</p> <p>Methods</p> <p>Female B10.Q-ncf1<sup>*/*</sup>mice were sham-operated or ovariectomized, and CIA was induced. 22 days later, when 30% of the mice had developed arthritis, treatment with raloxifene, estradiol or vehicle was started, and the clinical disease was evaluated continuously. Treatment was continued until day 56 after immunization. At termination of the experiment (day 73), bone mineral density (BMD) was analyzed, paws were collected for histological examination, and sera were analyzed for markers of cartilage turnover and pro-inflammatory cytokines.</p> <p>Results</p> <p>Raloxifene and estradiol treatment, as well as endogenous estrogen, decreased the frequency of arthritis, prevented joint destruction and countered generalized osteoporosis. These effects were associated with lower serum levels of the pro-inflammatory cytokine IL-6.</p> <p>Conclusions</p> <p>This is the first study to show that raloxifene and estradiol can ameliorate established erosive arthritis and inflammation-triggered osteoporosis in this chronic arthritis model. We propose that treatment with raloxifene could be a beneficial addition to the treatment of postmenopausal RA.</p

    ANALYS AV KOSTNADER FÖR LAST MILE DISTRIBUTION : MÖJLIGHETER MED KONSOLIDERING OCH DESS SYNERGIEFFEKTER

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    I dagslĂ€get lever 86 % av Sveriges befolkning i stadsomrĂ„den. Mellan Ă„r 1990 till 2015 ökade befolkningen i Sveriges största storstadsomrĂ„den med ca 26 % i Göteborg, ca 36 % i Stockholm och ca 31 % i Malmö. Detta har skapat hĂ„rdare konkurrens i frĂ„ga om ytan mellan bland annat bostĂ€der, nĂ€ringsliv, grönomrĂ„den och transportinfrastrukturen. Det Ă€r viktigt att redan i planeringsfasen vid stĂ€dernas utformning vĂ€ga in aspekterna för citydistributionen och skapa ett balanserat transportsystem. Vid ökade transporter inom en stad ökar faktorer sĂ„ som köer, trĂ€ngsel, koldioxidutslĂ€pp, kostnader, stress och olyckor. Syftet med undersökningen var att genom signifikanta teorier och datainsamling berĂ€kna kostnadsfördelningen av distributörernas ”last mile distribution”. Även ge underlag för att visualisera konsoliderings- och samlastningsmöjligheter dĂ€r antalet utlĂ€mnings- och upphĂ€mtningsstopp var tĂ€tare. Arbetet begrĂ€nsades till ett omrĂ„de inom Göteborgs innerstad och fordonstypen till paketbilar. Datainsamlingsperioden skedde frĂ„n och med den 23 mars 2016 till och med 25 april 2016. De teorier som lĂ„g till grund för arbetet Ă€r supply chain, distribution, citydistribution, Triple bottom line, kostnader för citydistribution, samlastning och konsolidering. Uppsatsen utgick ifrĂ„n kvantitativa metoder och vĂ€rdena analyserades frĂ„n en objektiv stĂ„ndpunkt. För att skaffa en grunduppfattning av last mile utfördes Ă€ven tvĂ„ semistrukturerade kvalitativa intervjuer. De utvalda respondenterna Ă€r forskare inom logistik. PrimĂ€rdata till uppsatsen Ă€r insamlad genom en tidsstudie med hjĂ€lp av applikationen Stardriver. Detta utfördes under 13 hela arbetsdagar tillsammans med marknadsledande distributionsfirmor inom paket och logistik i Sverige. Resultatet pĂ„visar att kostnadsfördelningen inom last mile till störst del fördelas pĂ„ aktiviteterna Drive, Handle to store och Unload. Aktiviteterna delades ocksĂ„ in beroende pĂ„ om de Ă€r vĂ€rdeskapande, stödjande eller förluster. Kontentan av det blev att 70% Ă€r vĂ€rdeskapande aktiviteter, 13% stödjande aktiviteter och 17% Ă€r rena förluster. Detta innebĂ€r att under ett kalenderĂ„r lĂ€gger distributören pĂ„ ett ungefĂ€r 501 269 kr pĂ„ vĂ€rdeskapande aktiviteter, 93 093 kr pĂ„ stödjande aktiviteter och 121 737 kr pĂ„ förluster. De aktiviteter som klassas som förlust bör elimineras för att minska kostnaderna. Även de andra aktiviteterna kan skapa mer kostnadseffektiva transporter genom exempelvis samlastning mellan distributörer och intern effektivisering. Möjligheterna för samlastning och konsolidering av paket inom centrala omrĂ„den i Göteborgs Ă€r goda enligt det data som samlades in. Baserat pĂ„ den tĂ€tare kundkrets som pĂ„trĂ€ffades inom den begrĂ€nsade ytan upprĂ€ttades tvĂ„ mindre omrĂ„den dĂ€r samlastning med fördel kan nyttjas. För att implementera samlastning mellan distributörerna krĂ€vs ett starkare samarbete mellan parterna. Alternativt att en oberoende part sĂ„ som Stadleveransen som tar hand om distributionen.

    BRUKARES SJÄLVBESTÄMMANDE – UTIFRÅN BRUKARENS OCH PERSONALENS PERSPEKTIV

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    Syftet med denna uppsats Àr att belysa personer med intellektuell funktionsnedsÀttning boende pÄ serviceboende och personalens upplevelser angÄende brukares sjÀlvbestÀmmande. Som metod har vi anvÀnt oss av semistrukturerade intervjuer med fyra brukare och fyra personal pÄ servicebostÀder i en kommun i södra Sverige. Som teoretisk ram har Scheffs, sociala band anvÀnts. Uppsatsen ÄskÄdliggör komplexiteten personalen upplever kring brukarnas sjÀlvbestÀmmande och hur detta utmanas av de relationer och beroende som finns brukare och personal emellan. SÀrskilt framkommer denna komplexitet i relationen mellan personalens ansvar, till exempel för brukarens hÀlsa kontra att tillförsÀkra brukarnas sjÀlvbestÀmmande. Brukarnas bild av hur de sjÀlva upplever att sjÀlvbestÀmmandet tar sig frekvent till uttryck kring vardagsaktiviteten. Det framkommer vidare att brukarna saknar full kunskap angÄende deras sjÀlvbestÀmmande men Àndock upplevs brukarna som nöjda med sitt faktiska sjÀlvbestÀmmande i vardagen. Trots riktlinjer och handlingsplaner upplever personalen att teori och praktik inte gÄr hand i hand vilket försvÄrar personalens arbete med brukarens sjÀlvbestÀmmandeThe purpose of this essay is to highlight the people with intellectual disabilities in service housing in a municipality and staff's experiences regarding the user's self-determination. As a method, we have used semi-structured interviews where we have interviewed four users and four staff in service housing in a municipality in southern Sweden. As a theoretical framework, Scheffs, social bond theory has been used. The essay illustrates the complexity of staff experience around people with intellectual disabilities self-determination and how this challenged by the relationships and dependencies that exist between people with intellectual disabilities and staff. In particular this complexity appears in the relationship between the staffŽs responsibility, for example people with intellectual disabilities health versus ensuring their self-determination. People with intellectual disabilities picture of how they themselves feel that self-determination manifests itself in everyday life. It also appears that the people with intellectual disabilities lack full knowledge of their self-determination, but despite this, the people with intellectual disabilities are perceived as satisfied with their actual self-determination in everyday life. Despite guidelines the staff experience that theory and practice do not go hand in hand, which makes the staff's work more difficult with the people with intellectual disabilities self-determination
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