Removing celiac disease-related gluten proteins from bread wheat while retaining technological properties: a study with Chinese Spring deletion lines

<p>Abstract</p> <p>Background</p> <p>Gluten proteins can induce celiac disease (CD) in genetically susceptible individuals. In CD patients gluten-derived peptides are presented to the immune system, which leads to a CD4⁺T-cell mediated immune response and inflammation of the small intestine. However, not all gluten proteins contain T-cell stimulatory epitopes. Gluten proteins are encoded by multigene loci present on chromosomes 1 and 6 of the three different genomes of hexaploid bread wheat (<it>Triticum aestivum</it>) (AABBDD).</p> <p>Results</p> <p>The effects of deleting individual gluten loci on both the level of T-cell stimulatory epitopes in the gluten proteome and the technological properties of the flour were analyzed using a set of deletion lines of <it>Triticum aestivum </it>cv. Chinese Spring. The reduction of T-cell stimulatory epitopes was analyzed using monoclonal antibodies that recognize T-cell epitopes present in gluten proteins. The deletion lines were technologically tested with respect to dough mixing properties and dough rheology. The results show that removing the α-gliadin locus from the short arm of chromosome 6 of the D-genome (6DS) resulted in a significant decrease in the presence of T-cell stimulatory epitopes but also in a significant loss of technological properties. However, removing the ω-gliadin, γ-gliadin, and LMW-GS loci from the short arm of chromosome 1 of the D-genome (1DS) removed T-cell stimulatory epitopes from the proteome while maintaining technological properties.</p> <p>Conclusion</p> <p>The consequences of these data are discussed with regard to reducing the load of T-cell stimulatory epitopes in wheat, and to contributing to the design of CD-safe wheat varieties.</p

Alpha-gliadin genes from the A, B, and D genomes of wheat contain different sets of celiac disease epitopes

BACKGROUND: Bread wheat (Triticum aestivum) is an important staple food. However, wheat gluten proteins cause celiac disease (CD) in 0.5 to 1% of the general population. Among these proteins, the α-gliadins contain several peptides that are associated to the disease. RESULTS: We obtained 230 distinct α-gliadin gene sequences from severaldiploid wheat species representing the ancestral A, B, and D genomes of the hexaploid bread wheat. The large majority of these sequences (87%) contained an internal stop codon. All α-gliadin sequences could be distinguished according to the genome of origin on the basis of sequence similarity, of the average length of the polyglutamine repeats, and of the differences in the presence of four peptides that have been identified as T cell stimulatory epitopes in CD patients through binding to HLA-DQ2/8. By sequence similarity, α-gliadins from the public database of hexaploid T. aestivum could be assigned directly to chromosome 6A, 6B, or 6D. T. monococcum (A genome) sequences, as well as those from chromosome 6A of bread wheat, almost invariably contained epitope glia-α9 and glia-α20, but never the intact epitopes glia-α and glia-α2. A number of sequences from T. speltoides, as well as a number of sequences fromchromosome 6B of bread wheat, did not contain any of the four T cell epitopes screened for. The sequences from T. tauschii (D genome), as well as those from chromosome 6D of bread wheat, were found to contain all of these T cell epitopes in variable combinations per gene. The differences in epitope composition resulted mainly from point mutations. These substitutions appeared to be genome specific. CONCLUSION: Our analysis shows that α-gliadin sequences from the three genomes of bread wheat form distinct groups. The four known T cell stimulatory epitopes are distributed non-randomly across the sequences, indicating that the three genomes contribute differently to epitope content. A systematic analysis of all known epitopes in gliadins and glutenins will lead to better understanding of the differences in toxicity among wheat varieties. On the basis of such insight, breeding strategies can be designed to generate less toxic varieties of wheat which may be tolerated by at least part of the CD patient population

A phase I dose-escalation study to evaluate safety and tolerability of sorafenib combined with sirolimus in patients with advanced solid cancer

Contains fulltext : 87630.pdf (publisher's version ) (Closed access)BACKGROUND: The combination of sorafenib (vascular endothelial growth factor receptor 2 inhibitor) and sirolimus (mammalian target of rapamycin inhibitor) might work synergistically. METHODS: A phase I dose-escalation study with sorafenib twice a day (b.i.d.) and sirolimus once daily (q.d.) was performed to determine the recommended dose of the combination in patients with solid tumours. Secondary objectives were to determine the safety profile and maximum tolerated dose (MTD), and to evaluate the pharmacokinetics (PK) of the combination. RESULTS: Dose-limiting toxicities were transaminitis and cutaneous toxicity. The most frequently reported adverse events were elevated transaminases, hypophosphatemia, fatigue, anorexia, diarrhoea, nausea, rash and palmar-plantar erythrodysaesthesia. Sirolimus did not change the PK of sorafenib; in contrast, sorafenib reduced the AUC(0-96) and C(max) of sirolimus. No objective responses were observed; eight patients showed stable disease for a median of 16.3 weeks (range 8-24). The MTD of the combination was sorafenib 200 mg b.i.d. with sirolimus 1 mg q.d. CONCLUSION: The combination of sorafenib and sirolimus showed enhanced toxicity, which could not be explained by the PK of both drugs. The relative low doses at the MTD, in combination with the PK results, do not warrant further development of this combination

Interleukin-2/interferon-α2a/13-retinoic acid-based chemoimmunotherapy in advanced renal cell carcinoma: results of a prospectively randomised trial of the German Cooperative Renal Carcinoma Chemoimmunotherapy Group (DGCIN)

We performed a prospectively randomised clinical trial to compare the efficacy of four subcutaneous interleukin-2-(sc-IL-2) and sc interferon-α2a (sc-IFN-α2a)-based outpatient regimens in 379 patients with progressive metastatic renal cell carcinoma. Patients with lung metastases, an erythrocyte sedimentation rate ⩽70 mm h−1 and neutrophil counts ⩽6000 μl−1 (group I) were randomised to arm A: sc-IL-2, sc-IFN-α2a, peroral 13-cis-retinoic acid (po-13cRA) (n=78), or arm B: arm A plus inhaled-IL-2 (n=65). All others (group II) were randomised to arm C: arm A plus intravenous 5-fluorouracil (iv-5-FU) (n=116), or arm D: arm A plus po-Capecitabine (n=120). Median overall survival (OS) was 22 months (arm A; 3-year OS: 29.7%) and 18 months (arm B; 3-year OS: 29.2%) in group I, and 18 months (arm C; 3-year OS: 25.7%) and 16 months (arm D; 3-year OS: 32.6%) in group II. There were no statistically significant differences in OS, progression-free survival, and objective response between arms A and B, and between arms C and D, respectively. Given the known therapeutic efficacy of sc-IL-2/sc-INF-α2a/po-13cRA-based outpatient chemoimmunotherapies, our results did not establish survival advantages in favour of po-Capecitabine vs iv-5-FU, and in favour of short-term inhaled-IL-2 in patients with advanced renal cell carcinoma receiving systemic cytokines

CD70 (TNFSF7) is expressed at high prevalence in renal cell carcinomas and is rapidly internalised on antibody binding

In order to identify potential markers of renal cancer, the plasma membrane protein content of renal cell carcinoma (RCC)-derived cell lines was annotated using a proteomics process. One unusual protein identified at high levels in A498 and 786-O cells was CD70 (TNFSF7), a type II transmembrane receptor normally expressed on a subset of B, T and NK cells, where it plays a costimulatory role in immune cell activation. Immunohistochemical analysis of CD70 expression in multiple carcinoma types demonstrated strong CD70 staining in RCC tissues. Metastatic tissues from eight of 11 patients with clear cell RCC were positive for CD70 expression. Immunocytochemical analysis demonstrated that binding of an anti-CD70 antibody to CD70 endogenously expressed on the surface of A498 and 786-O cell lines resulted in the rapid internalisation of the antibody–receptor complex. Coincubation of the internalising anti-CD70 antibody with a saporin-conjugated secondary antibody before addition to A498 cells resulted in 50% cell killing. These data indicate that CD70 represents a potential target antigen for toxin-conjugated therapeutic antibody treatment of RCC