Search results for "Langerhan"
showing 10 items of 138 documents
Monocyte-derived inflammatory Langerhans cells and dermal dendritic cells mediate psoriasis-like inflammation
2016
Dendritic cells (DCs) have been implicated in the pathogenesis of psoriasis but the roles for specific DC subsets are not well defined. Here we show that DCs are required for psoriasis-like changes in mouse skin induced by the local injection of IL-23. However, Flt3L-dependent DCs and resident Langerhans cells are dispensable for the inflammation. In epidermis and dermis, the critical DCs are TNF-producing and IL-1β-producing monocyte-derived DCs, including a population of inflammatory Langerhans cells. Depleting Ly6Chi blood monocytes reduces DC accumulation and the skin changes induced either by injecting IL-23 or by application of the TLR7 agonist imiquimod. Moreover, we find that IL-23-…
Solid nanoemulsion as antigen and immunopotentiator carrier for transcutaneous immunization
2015
Imiquimod, a toll-like receptor 7 (TLR7) agonist, is an active pharmaceutical ingredient (API) established for the topical treatment of several dermal cancerous and precancerous skin lesions. Within this work, the immunostimulatory effect of imiquimod is further exploited in a transcutaneous immunization (TCI) approach based on a solid nanoemulsion (SN) formulation. SN contains a combination of imiquimod with the model peptide antigen SIINFEKL as a novel approach to omit needle and syringe and optimize dermal antigen administration. Excipients including sucrose fatty acid esters and the pharmaceutically acceptable oils MCT (middle chain triglycerides), avocado oil, jojoba wax and squalene a…
Transcutaneous immunization with a novel imiquimod nanoemulsion induces superior T cell responses and virus protection
2017
Abstract Background Transcutaneous immunization (TCI) is a novel vaccination strategy utilizing the skin associated lymphatic tissue to induce immune responses. TCI using a cytotoxic T lymphocyte (CTL) epitope and the Toll-like receptor 7 (TLR7) agonist imiquimod mounts strong CTL responses by activation and maturation of skin-derived dendritic cells (DCs) and their migration to lymph nodes. However, TCI based on the commercial formulation Aldara only induces transient CTL responses that needs further improvement for the induction of durable therapeutic immune responses. Objective Therefore we aimed to develop a novel imiquimod solid nanoemulsion (IMI-Sol) for TCI with superior vaccination …
Type 1 diabetes associated autoimmunity.
2016
Diabetes mellitus is increasing in prevalence worldwide. The economic costs are considerable given the cardiovascular complications and co-morbidities that it may entail. Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by the loss of insulin-producing pancreatic β-cells. The pathogenesis of T1D is complex and multifactorial and involves a genetic susceptibility that predisposes to abnormal immune responses in the presence of ill-defined environmental insults to the pancreatic islets. Genetic background may affect the risk for autoimmune disease and patients with T1D exhibit an increased risk of other autoimmune disorders such as autoimmune thyroid disease, Addison's dise…
Changes in the Peripheral Endocannabinoid System as a Risk Factor for the Development of Eating Disorders
2017
BACKGROUND AND OBJECTIVE Eating Disorder (ED) is characterized by persistently and severely disturbed eating behaviours. They arise from a combination of long-standing behavioural, emotional, psychological, interpersonal, and social factors and result in insufficient nutrient ingestion and/or adsorption. The three main EDs are: anorexia nervosa, bulimia nervosa, and binge eating disorder. We review the role of peripheral endocannabinoids in eating behaviour. DISCUSSION The neuronal pathways involved in feeding behaviours are closely related to catecholaminergic, serotoninergic and peptidergic systems. Accordingly, feeding is promoted by serotonin, dopamine, and prostaglandin and inhibited b…
Long-term graft function of adult rat and human islets encapsulated in novel alginate-based microcapsules after transplantation in immunocompetent di…
2005
We describe the results of the first study to show that adult rat and human islets can be protected against xenogenic rejection in immunocompetent diabetic mice by encapsulating them in a novel alginate-based microcapsule system with no additional permselective membrane. Nonencapsulated islets lost function within 4–8 days after being transplanted into diabetic Balb/c mice, whereas transplanted encapsulated adult rat or human islets resulted in normoglycemia for >7 months. When rat islet grafts were removed 10 and 36 weeks after transplantation, the mice became immediately hyperglycemic, thus demonstrating the efficacy of the encapsulated islets. The explanted capsules showed only a …
CD40 activation in human pancreatic islets and ductal cells.
2008
Aims/hypothesis: CD40 expression on non-haematopoietic cells is linked to inflammation. We previously reported that CD40 is expressed on isolated human and non-human primate islets and its activation results in secretion of IL-8, macrophage inflammatory protein 1-beta (MIP-1β) and monocyte chemoattractant protein-1 (MCP-1) through nuclear factor-κB and extracellularly regulated kinases 1/2 pathways. The objective of this study was to identify the pattern of gene expression, and to study viability and functionality affected by CD40-CD40 ligand (CD40L) interaction in human islets. Furthermore, we have studied the CD40-mediated cytokine/chemokine profile in pancreatic ductal cells, as they are…
Beyond islet trasplantation in diabetes cell terapy:from embryonic stem cells to transdifferentation of adult cells
2013
Exogenous insulin is, at the moment, the therapy of choice of diabetes, but does not allow tight regulation of glucose leading to long-term complications. Recently, pancreatic islet transplantation to reconstitute insulin-producing cells, has emerged as an alternative promising therapeutic approach. Unfortunately, the number of donor islets is too low compared with the high number of patients needing a transplantation leading to a search for renewable sources of high-quality -cells. This review, summarizes more recent promising approaches to the generation of new -cells from embryonic stem cells for transdifferentiation of adult cells, particularly a critical examination of the seminal work…
Modification of Peripheral Blood T-Lymphocyte Surface Receptors and Langerhans Cell Numbers in Hereditary Angioedema
1986
Hereditary angioedema (HAE) is a disease related to a complement disorder, namely a deficiency of C1 esterase inhibitor. Complement-split products are implicated in the regulation of the immune response, and we have compared some immunologic parameters between HAE and normal individuals. T-lymphocytes with receptors for IgG were increased in HAE, but no difference in T-cell suppressor activity for B-cells was detected. Furthermore, increased IgG receptor expression was not accompanied by any significant changes in the ratios of OKT4- and OKT8-defined antigens. Numbers of peripheral mononuclear cells (MNC) detected by alpha-naphthyl acetate esterase (ANAE) staining positivity were not signif…
INFLUENCE OF ISLET TRANSPORTATION ON PANCREATIC ISLET ALLOTRANSPLANTATION IN TYPE 1 DIABETIC PATIENTS WITHIN THE SWISS-FRENCH GRAGIL NETWORK
2004
The influence of islet transportation on pancreatic islet allotransplantation in type 1 diabetic patients was evaluated within the GRAGIL network.From December 2001 to April 2003, 16 human pancreatic islet transplants were performed in 9 type 1 diabetic patients with an established kidney graft (functioning for at least 6 months) in four centers of the GRAGIL network. Islet isolation was performed in a core laboratory in Geneva, and the islet preparations were shipped by ambulance to each center for transplantation. One month after transplantation, the efficiency of the graft was assessed according to islet transportation time (ITT): ITT less than 2 hours (group 1, n=5), and ITT greater tha…