Polymorphism of a new Ty1-copia retrotransposon in durum wheat under salt and light stresses

Long terminal repeat retrotransposons are the most abundant mobile elements in the plant genome and play an important role in the genome reorganization induced by environmental challenges. Their success depends on the ability of their promoters to respond to different signaling pathways that regulate plant adaptation to biotic and abiotic stresses. We have isolated a new Ty1-copia-like retrotransposon, named Ttd1a from the Triticum durum L. genome. To get insight into stress activation pathways in Ttd1a, we investigated the effect of salt and light stresses by RT-PCR and S-SAP profiling. We screened for Ttd1a insertion polymorphisms in plants grown to stress and showed that one new insertion was located near the resistance gene. Our analysis showed that the activation and mobilization of Ttd1a was controlled by salt and light stresses, which strengthened the hypothesis that stress mobilization of this element might play a role in the defense response to environmental stresses.     

Antibody responses to NY-ESO-1 in primary breast cancer identify a subtype target for immunotherapy

The highly immunogenic human tumor antigen NY-ESO-1 (ESO) is a target of choice for anti-cancer immune therapy. In this study, we assessed spontaneous antibody (Ab) responses to ESO in a large cohort of patients with primary breast cancer (BC) and addressed the correlation between the presence of anti-ESO Ab, the expression of ESO in the tumors and their characteristics. We found detectable Ab responses to ESO in 1% of the patients. Tumors from patients with circulating Ab to ESO exhibited common characteristics, being mainly hormone receptor (HR)⁻ invasive ductal carcinomas of high grade, including both HER2⁻ and HER2⁺ tumors. In line with these results, we detected ESO expression in 20% of primary HR⁻ BC, including both ESO Ab⁺ and Ab⁻ patients, but not in HR⁺ BC. Interestingly, whereas expression levels in ESO⁺ BC were not significantly different between ESO Ab⁺ and Ab⁻ patients, the former had, in average, significantly higher numbers of tumor-infiltrated lymph nodes, indicating that lymph node invasion may be required for the development of spontaneous anti-tumor immune responses. Thus, the presence of ESO Ab identifies a tumor subtype of HR⁻ (HER2⁻ or HER2⁺) primary BC with frequent ESO expression and, together with the assessment of antigen expression in the tumor, may be instrumental for the selection of patients for whom ESO-based immunotherapy may complement standard therapy.     

Assessment of CD4<Superscript>+</Superscript> T cells specific for the tumor antigen SSX-1 in cancer-free individuals

Proteins encoded by genes of the SSX family are specifically expressed in tumors and are therefore relevant targets for cancer immunotherapy. One of the first identified family members, SSX-1, is expressed in a large fraction of synovial sarcomas as a fusion protein together with the product of the SYT gene. In addition, the full-length SSX-1 antigen is frequently expressed in tumors of several other histological types such as sarcoma, melanoma, hepatocellular carcinoma, ovarian cancer and myeloma. To date, however, SSX-1 specific T cell responses have not been investigated and no SSX-1 derived T cell epitopes have been described. Here, we have assessed the presence of CD4(+) T cells directed against the SSX-1 antigen in circulating lymphocytes of cancer-free individuals. After a single in vitro stimulation with a pool of peptides spanning the entire SSX-1 protein we could detect and isolate SSX-1-specific CD4(+) T cells from 5/5 donors analyzed. SSX-1-specific polyclonal populations isolated from these cultures recognized peptides located in three distinct regions of the protein containing clusters of sequences with significant predicted binding to frequently expressed MHC class II alleles. Characterization of specific clonal CD4(+) T cell populations derived from one donor allowed the identification of several naturally processed epitopes recognized in association with HLA-DR. These data document the existence of a significant repertoire of CD4(+) T cells specific for SSX-1 derived sequences in circulating lymphocytes of any individual that can be exploited for the development of both passive and active immunotherapeutic approaches to control disease evolution in cancer patients.     

Influence of Water Activity and System Mobility on Peroxidase Activity in Maltodextrin Solutions

Maltodextrins influenced the enzymatic activity in aqueous solutions by affecting the water activity (a_w) and mobility as described by viscosity and T’g. In diluted solutions, viscosity being equal, (1) maltodextrin with dextrose equivalents (DE) of 33 was more effective than glucose in limiting horseradish peroxidase (HRP) activity; (2) an increase in the maltodextrin chain length from DE 33 to DE 8.7 did not further limited enzymatic activity; (3) the maltodextrin with the highest chain length (DE 2.5) determined the highest enzyme inhibition. In general, the increase of molecular weight negatively affected the HRP activity by increasing the viscosity and T’g (decreasing molecular mobility) but it positively affected the a_w and, in some cases, this compensated the HRP activity inhibition. In concentrated solutions (apparent viscosity ≈ 40 mPa s) the HRP activity decreased with the increase of the maltodextrin molecular weight, and it showed a dependence on T’g which could be described by a William, Landel and Ferry (WLF)-type equation. On the contrary, in the solution added with the maltodextrin with the highest chain length (DE 2.5) the HRP activity was much higher than that predicted by the WLF-type equation. The maltodextrin with DE 2.5 contains intact starch fragments and in water forms a suspension. In such a discontinuous system, the viscosity in the vicinity of the protein is lower than the bulk viscosity, and thus, the enzyme activity is higher than expected. Moreover, since T’g is a property of the soluble phase, it does not explain the mobility in discontinuous systems.     

Staphylococcal toxic shock syndrome 2000-2006: epidemiology, clinical features, and molecular characteristics

Introduction

Circulating strains of Staphylococcus aureus (SA) have changed in the last 30 years including the emergence of community-associated methicillin-resistant SA (MRSA). A report suggested staphylococcal toxic shock syndrome (TSS) was increasing over 2000–2003. The last population-based assessment of TSS was 1986.

Methods

Population-based active surveillance for TSS meeting the CDC definition using ICD-9 codes was conducted in the Minneapolis-St. Paul area (population 2,642,056) from 2000–2006. Medical records of potential cases were reviewed for case criteria, antimicrobial susceptibility, risk factors, and outcome. Superantigen PCR testing and PFGE were performed on available isolates from probable and confirmed cases.

Results

Of 7,491 hospitalizations that received one of the ICD-9 study codes, 61 TSS cases (33 menstrual, 28 non-menstrual) were identified. The average annual incidence per 100,000 of all, menstrual, and non-menstrual TSS was 0.52 (95% CI, 0.32–0.77), 0.69 (0.39–1.16), and 0.32 (0.12–0.67), respectively. Women 13–24 years had the highest incidence at 1.41 (0.63–2.61). No increase in incidence was observed from 2000–2006. MRSA was isolated in 1 menstrual and 3 non-menstrual cases (7% of TSS cases); 1 isolate was USA400. The superantigen gene tst-1 was identified in 20 (80%) of isolates and was more common in menstrual compared to non-menstrual isolates (89% vs. 50%, p = 0.07). Superantigen genes sea, seb and sec were found more frequently among non-menstrual compared to menstrual isolates [100% vs 25% (p = 0.4), 60% vs 0% (p<0.01), and 25% vs 13% (p = 0.5), respectively].

Discussion

TSS incidence remained stable across our surveillance period of 2000–2006 and compared to past population-based estimates in the 1980s. MRSA accounted for a small percentage of TSS cases. tst-1 continues to be the superantigen associated with the majority of menstrual cases. The CDC case definition identifies the most severe cases and has been consistently used but likely results in a substantial underestimation of the total TSS disease burden.     

20S proteasome mediated degradation of DHFR: implications in neurodegenerative disorders

The 20S proteasome is responsible for the degradation of protein substrates implicated in the onset and progression of neurodegenerative disorders, such as alpha-synuclein and tau protein. Here we show that the 20S proteasome isolated from bovine brain directly hydrolyzes, in vitro, the dihydrofolate reductase (DHFR), demonstrated to be involved in the pathogenesis of neurodegenerative diseases. Furthermore, the DHFR susceptibility to proteolysis is enhanced by oxidative conditions induced by peroxynitrite, mimicking the oxidative environment typical of these disorders. The results obtained suggest that the folate metabolism may be impaired by an increased degradation of DHFR, mediated by the 20S proteasome.     

Is Aboriginal Food Less Allergenic? Comparing IgE-Reactivity of Eggs from Modern and Ancient Chicken Breeds in a Cohort of Allergic Children

Background

Hen''s egg allergy ranks among the most frequent primary food allergies in children. We aimed to investigate sensitization profiles of egg allergic patients and compare in vitro IgE reactivities of eggs from ancient chicken breeds (Araucana and Maran) with those from conventional laying hen hybrids.

Methodology

Egg allergic children (n = 25) were subjected to skin prick test, double blind placebo controlled food challenge, and sensitization profiles to Gal d 1–5 were determined by allergen microarray. IgE binding and biological activity of eggs from different chicken breeds were investigated by immunoblot, ELISA, and mediator release assays.

Principal Findings

We found that Gal d 1 and Gal d 2 are generally major egg allergens, whereas Gal d 3–5 displayed high sensitization prevalence only in patients reacting to both, egg white and yolk. It seems that the onset of egg allergy is mediated by egg white allergens expanding to yolk sensitization in later stages of disease. Of note, egg white/yolk weight ratios were reduced in eggs from Auraucana and Maran chicken. As determined in IgE immunoblots and mass analysis, eggs from ancient chicken breeds did not differ in their protein composition. Similar IgE-binding was observed for all egg white preparations, while an elevated allergenicity was detected in egg yolk from Araucana chicken.

Conclusion/Significance

Our results on allergenicity and biological activity do not confirm the common assumption that aboriginal food might be less allergenic. Comprehensive diagnosis of egg allergy should distinguish between reactivity to hen''s egg white and yolk fractions to avoid unnecessary dietary restrictions to improve life quality of the allergic child and its family.