Gut T cell receptor-gammadelta(+) intraepithelial lymphocytes are activated selectively by cholera toxin to break oral tolerance in mice

Item does not contain fulltextThe gut immune system is usually tolerant to harmless foreign antigens such as food proteins. However, tolerance breakdown may occur and lead to food allergy. To study mechanisms underlying food allergy, animal models have been developed in mice by using cholera toxin (CT) to break tolerance. In this study, we identify T cell receptor (TCR)-gammadelta(+) intraepithelial lymphocytes (IELs) as major targets of CT to break tolerance to food allergens. TCR-gammadelta(+) IEL-enriched cell populations isolated from mice fed with CT and transferred to naive mice hamper tolerization to the food allergen beta-lactoglobulin (BLG) in recipient mice which produce anti-BLG immunoglobulin (Ig)G1 antibodies. Furthermore, adoptive transfer of TCR-gammadelta(+) cells from CT-fed mice triggers the production of anti-CT IgG1 antibodies in recipient mice that were never exposed to CT, suggesting antigen-presenting cell (APC)-like functions of TCR-gammadelta(+) IELs. In contrast to TCR-alphabeta(+) cells, TCR-gammadelta(+) IELs bind and internalize CT both in vitro and in vivo. CT-activated TCR-gammadelta(+) IELs express major histocompatibility complex (MHC) class II molecules, CD80 and CD86 demonstrating an APC phenotype. CT-activated TCR-gammadelta(+) IELs migrate to the lamina propria, where they produce interleukin (IL)-10 and IL-17. These results provide in-vivo evidence for a major role of TCR-gammadelta(+) IELs in the modulation of oral tolerance in the pathogenesis of food allergy

A comprehensive 1000 Genomes-based genome-wide association meta-analysis of coronary artery disease

Existing knowledge of genetic variants affecting risk of coronary artery disease (CAD) is largely based on genome-wide association study (GWAS) analysis of common SNPs. Leveraging phased haplotypes from the 1000 Genomes Project, we report a GWAS meta-analysis of ∼185,000 CAD cases and controls, interrogating 6.7 million common (minor allele frequency (MAF) > 0.05) and 2.7 million low-frequency (0.005 < MAF < 0.05) variants. In addition to confirming most known CAD-associated loci, we identified ten new loci (eight additive and two recessive) that contain candidate causal genes newly implicating biological processes in vessel walls. We observed intralocus allelic heterogeneity but little evidence of low-frequency variants with larger effects and no evidence of synthetic association. Our analysis provides a comprehensive survey of the fine genetic architecture of CAD, showing that genetic susceptibility to this common disease is largely determined by common SNPs of small effect size. © 2015 Nature America, Inc

Garantenstellung des Wohnungsinhabers bei Angriffen auf einen Gast

Garantenstellung des Wohnungsinhabers bei Angriffen auf einen Gast. - In: Juristische Schulung. 18. 1978. S. 308-31

Genome-wide association identifies nine common variants associated with fasting proinsulin levels and provides new insights into the pathophysiology of type 2 diabetes

OBJECTIVE - Proinsulin is a precursor of mature insulin and C-peptide. Higher circulating proinsulin levels are associated with impaired b-cell function, raised glucose levels, insulin resistance, and type 2 diabetes (T2D). Studies of the insulin processing pathway could provide new insights about T2D pathophysiology. RESEARCH DESIGN AND METHODS - We have conducted a meta-analysis of genome-wide association tests of ;2.5 million genotyped or imputed single nucleotide polymorphisms (SNPs) and fasting proinsulin levels in 10,701 nondiabetic adults of European ancestry, with follow-up of 23 loci in up to 16,378 individuals, using additive genetic models adjusted for age, sex, fasting insulin, and study-specific covariates. RESULTS - Nine SNPs at eight loci were associated with proinsulin levels (P < 5 × 10-8). Two loci (LARP6 and SGSM2) have not been previously related to metabolic traits, one (MADD) has been associated with fasting glucose, one (PCSK1) has been implicated in obesity, and four (TCF7L2, SLC30A8, VPS13C/ C2CD4A/B, and ARAP1, formerly CENTD2) increase T2D risk. The proinsulin-raising allele of ARAP1 was associated with a lower fasting glucose (P = 1.7 3 10-4), improved b-cell function (P = 1.1 × 10-5), and lower risk of T2D (odds ratio 0.88; P = 7.8 × 10-6). Notably, PCSK1 encodes the protein prohormone convertase 1/3, the first enzyme in the insulin processing pathway. A genotype score composed of the nine proinsulin-raising alleles was not associated with coronary disease in two large case-control datasets. CONCLUSIONS - We have identified nine genetic variants associated with fasting proinsulin. Our findings illuminate the biology underlying glucose homeostasis and T2D development in humans and argue against a direct role of proinsulin in coronary artery disease pathogenesis