49 research outputs found
Immune stimulation mediated by autoantigen binding sites within small nuclear RNAs involves Toll-like receptors 7 and 8
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of autoantibodies to certain cellular macromolecules, such as the small nuclear ribonucleoprotein particles (snRNPs), which had been considered to be passive targets of the autoimmune response. SLE is also characterized by the increased expression of type I interferon (IFN), which appears to be associated with the development and severity of disease. Here, we show that specific, highly conserved RNA sequences within snRNPs can stimulate Toll-like receptors (TLRs) 7 and 8 as well as activate innate immune cells, such as plasmacytoid dendritic cells (pDCs), which respond by secreting high levels of type I IFN. SLE patient sera containing autoantibodies to snRNPs form immune complexes that are taken up through the Fc receptor ÎłRII and efficiently stimulate pDCs to secrete type I IFNs. These results demonstrate that a prototype autoantigen, the snRNP, can directly stimulate innate immunity and suggest that autoantibodies against snRNP may initiate SLE by stimulating TLR7/8
Cell Free DNA of Tumor Origin Induces a 'Metastatic' Expression Profile in HT-29 Cancer Cell Line
BACKGROUND: Epithelial cells in malignant conditions release DNA into the extracellular compartment. Cell free DNA of tumor origin may act as a ligand of DNA sensing mechanisms and mediate changes in epithelial-stromal interactions. AIMS: To evaluate and compare the potential autocrine and paracrine regulatory effect of normal and malignant epithelial cell-related DNA on TLR9 and STING mediated pathways in HT-29 human colorectal adenocarcinoma cells and normal fibroblasts. MATERIALS AND METHODS: DNA isolated from normal and tumorous colonic epithelia of fresh frozen surgically removed tissue samples was used for 24 and 6 hour treatment of HT-29 colon carcinoma and HDF-alpha fibroblast cells. Whole genome mRNA expression analysis and qRT-PCR was performed for the elements/members of TLR9 signaling pathway. Immunocytochemistry was performed for epithelial markers (i.e. CK20 and E-cadherin), DNA methyltransferase 3a (DNMT3a) and NFkappaB (for treated HDFalpha cells). RESULTS: Administration of tumor derived DNA on HT29 cells resulted in significant (p/=1, p/=1, p</=0.05), including increased expression of key adaptor molecules of TLR9 pathway (e.g. MYD88, IRAK2, NFkappaB, IL8, IL-1beta), STING pathway (ADAR, IRF7, CXCL10, CASP1) and the FGF2 gene. CONCLUSIONS: DNA from tumorous colon epithelium, but not from the normal epithelial cells acts as a pro-metastatic factor to HT-29 cells through the overexpression of pro-metastatic genes through TLR9/MYD88 independent pathway. In contrast, DNA derived from healthy colonic epithelium induced TLR9 and STING signaling pathway in normal fibroblasts
“Regards croisés sur la revue Semen, un espace de rencontres interdisciplinaire”
La revue Semen occupe une place particulière au sein de la communauté en Sciences de l’information et de la communication (SIC). Cet entretien croisé a pour enjeu de représenter la rencontre entre les Sciences du langage (SDL), l’Analyse du discours et les SIC. Trois chercheurs en SIC ont bien voulu relever le défi : Julien Auboussier (ÉLICO), Alice Krieg-Planque (CÉDITEC) et Alexandra Saemmer (CÉMTI). Cette rencontre se structure en trois axes de réflexion : la question de l’interdisciplinarité, la professionnalisation de la revue et la possible évolution de la ligne éditoriale en contexte de cris
“Regards croisés sur la revue Semen, un espace de rencontres interdisciplinaire”
La revue Semen occupe une place particulière au sein de la communauté en Sciences de l’information et de la communication (SIC). Cet entretien croisé a pour enjeu de représenter la rencontre entre les Sciences du langage (SDL), l’Analyse du discours et les SIC. Trois chercheurs en SIC ont bien voulu relever le défi : Julien Auboussier (ÉLICO), Alice Krieg-Planque (CÉDITEC) et Alexandra Saemmer (CÉMTI). Cette rencontre se structure en trois axes de réflexion : la question de l’interdisciplinarité, la professionnalisation de la revue et la possible évolution de la ligne éditoriale en contexte de cris
Regards croisés sur la revue Semen, un espace de rencontres interdisciplinaire
International audienc
Tumor-associated FGF-23-induced hypophosphatemic rickets in children: a case report and review of the literature
Background: Tumor-associated fibroblast growth factor 23 (FGF-23)-induced hypophosphatemic rickets is a rare but known pediatric entity first described in 1959. It results from local production of phosphatonins by benign and malignant mesenchymal tumors. Case-Diagnosis/Treatment: We report an 8-year-old boy with tumor-associated hypophosphatemic rickets due to paraneoplastic FGF-23 secretion from a benign mesenchymal pelvic-bone tumor. Excessive FGF-23 production was visualized by immunohistochemistry in the resected tumor. Phosphate wasting stopped immediately after tumor resection. We reviewed 26 reports of pediatric patients with tumor-induced hypophosphatemic rickets; paraneoplastic FGF-23 secretion was documented in only three of them. All tumors developed inside bone, were benign in 21/26 cases, and were localized in femur/tibia (13/26), radius/ulna/humerus (7/26), pelvis (4/26), rib (1/26), and craniofacial (1/26) bones. Mean interval between onset of signs and/or symptoms and diagnosis was 34months. Conclusions: In patients with hypophosphatemic rickets acquired beyond infancy, radiologic investigations for bone tumors need to be performed rapidly. In contrast to biochemical screening for increased circulating FGF-23 levels, immunohistochemical confirmation of FGF-23 production in resected tumor tissue can be regarded as being well established
The proton-activated receptor GPR4 modulates intestinal inflammation
BACKGROUND AND AIMS: During active inflammation tissue intraluminal intestinal pH is decreased in patients with inflammatory bowel disease (IBD). Acidic pH may play a role in IBD pathophysiology. Recently, proton sensing G-protein coupled receptors were identified, including GPR4, OGR1 (GPR68), and TDAG8 (GPR65). We investigated whether GPR4 is involved in intestinal inflammation.
METHODS: The role of GPR4 was assessed in murine colitis models: chronic dextran sulphate sodium (DSS) administration and by crossbreeding into an IL-10 deficient background for development of spontaneous colitis. Colitis severity was assessed by body weight, colonoscopy, colon length, histological score, cytokine mRNA expression, and myeloperoxidase (MPO) activity. In the spontaneous Il-10-/- colitis model, the incidence of rectal prolapse and characteristics of lamina propria leukocytes (LPLs) were analyzed.
RESULTS: Gpr4-/- mice showed reduced body weight loss and histology score after induction of chronic DSS colitis. In Gpr4-/- /Il-10-/- double knock-outs the onset and progression of rectal prolapse were significantly delayed and mitigated compared to Gpr4+/+ /Il-10-/- mice. Double knock-out mice showed lower histology scores, MPO activity, CD4 + T-helper cell infiltration, IFN-Îł, iNOS, MCP-1 (CCL2), CXCL1 and CXCL2 expression compared to controls. In colon, GPR4 mRNA was detected in endothelial cells, some smooth muscle cells, and some macrophages.
CONCLUSION: Absence of GPR4 ameliorates colitis in IBD animal models indicating an important regulatory rolein mucosal inflammation, thus providing a new link between tissue pH and the immune system. Therapeutic inhibition of GPR4 may be beneficial for the treatment of IBD
Germ stem cell transplantation procedure for the regeneration of isogenic trout lines
Germ stem cell transplantation procedure for the regeneration of isogenic trout lines. 11. International Symposium on Reproductive Physiology of Fis
Germ stem cell transplantation procedure for the regeneration of isogenic trout lines
Germ stem cell transplantation procedure for the regeneration of isogenic trout lines. 11. International Symposium on Reproductive Physiology of Fis