Metabolic changes during wheat microspore embryogenesis induction using the highly responsive cultivar Svilena.

Androgenetically-derived haploids can be obtained by inducing embryogenesis in microspores. Thus, full homozygosity is achieved in a single generation, oppositely to conventional plant breeding programs. Here, the metabolite profile of embryogenic microspores of Triticum aestivum was acquired and integrated with transcriptomic existing data from the same samples in an effort to identify the key metabolic processes occurring during the early stages of microspore embryogenesis. Primary metabolites and transcription profiles were identified at three time points: prior to and immediately following a low temperature pre-treatment given to uninuclear microspores, and after the first nuclear division. This is the first time an integrative -omics analysis is reported in microspore embryogenesis in T. aestivum. The key findings were that the energy produced during the pre-treatment was obtained from the tricarboxylic acid (TCA) cycle and from starch degradation, while starch storage resumed after the first nuclear division. Intermediates of the TCA cycle were highly demanded from a very active amino acid metabolism. The transcription profiles of genes encoding enzymes involved in amino acid synthesis differed from the metabolite profiles. The abundance of glutamine synthetase was correlated with that of glutamine. Cytosolic glutamine synthetase isoform 1 was found predominantly after the nuclear division. Overall, energy production was shown to represent a major component of the de-differentiation process induced by the pre-treatment, supporting a highly active amino acid metabolism.

Allergenicity of two Anisakis simplex allergens evaluated in vivo using an experimental mouse model.

Anisakis (Anisakidae) is one of the most important causes of helminth-induced allergic reactions and elicits clinical responses that include urticaria, rhinitis, bronco-constriction, cough, and/or gastrointestinal symptoms. More than 13 reactive allergens have been identified in the serum of Anisakis allergy patients, but the allergenicity of only a few of these have been evaluated in vivo using a mouse model. To evaluate the allergenicity of two important allergens, Ani s 1 and Ani s 9, we induced experimental allergic airway inflammation in a mouse model by repeated intranasal administration of the allergens. Both recombinant proteins (rAni s 1 and rAni s 9) elicited increased airway hyperresponsivity, airway infiltration by inflammatory cells (especially eosinophils), bronchial epithelial cell hyperplasia, all of which are characteristic of allergic airway inflammation. These allergens significantly increased the levels of Th2-related cytokines (IL-4, IL-5, IL-13, and IL-25) and Th17 related cytokines (IL-6 and IL-17) in both splenocytes and airway (except IL-17 in airway by rAni s 9). OVA-specific IgE and total IgE were increased in rAni s 1 and rAni s 9 treated mice as compared with controls treated with OVA alone. In addition, these two allergens induced gene expression of thymic stromal lymphopoietin (TSLP) and IL-25 (initiators of the Th2 response), as well as CXCL1 (initiator of the Th17 response) in mouse lung epithelial cells. In conclusion, repeated intranasal treatments with rAni s 1 and rAni s 9 induced airway inflammation in mice by elevating of Th2 and Th17 responses in the lung.

Relationships between IgE/IgG4 epitopes, structure and function in Anisakis simplex Ani s 5, a member of the SXP/RAL-2 protein family.

BACKGROUND: Anisakiasis is a re-emerging global disease caused by consumption of raw or lightly cooked fish contaminated with L3 Anisakis larvae. This zoonotic disease is characterized by severe gastrointestinal and/or allergic symptoms which may misdiagnosed as appendicitis, gastric ulcer or other food allergies. The Anisakis allergen Ani s 5 is a protein belonging to the SXP/RAL-2 family; it is detected exclusively in nematodes. Previous studies showed that SXP/RAL-2 proteins are active antigens; however, their structure and function remain unknown. The aim of this study was to elucidate the three-dimensional structure of Ani s 5 and its main IgE and IgG4 binding regions. METHODOLOGY/PRINCIPAL FINDINGS: The tertiary structure of recombinant Ani s 5 in solution was solved by nuclear magnetic resonance. Mg2+, but not Ca2+, binding was determined by band shift using SDS-PAGE. IgE and IgG4 epitopes were elucidated by microarray immunoassay and SPOTs membranes using sera from nine Anisakis allergic patients. The tertiary structure of Ani s 5 is composed of six alpha helices (H), with a Calmodulin like fold. H3 is a long, central helix that organizes the structure, with H1 and H2 packing at its N-terminus and H4 and H5 packing at its C-terminus. The orientation of H6 is undefined. Regarding epitopes recognized by IgE and IgG4 immunoglobulins, the same eleven peptides derived from Ani s 5 were bound by both IgE and IgG4. Peptides 14 (L40-K59), 26 (A76-A95) and 35 (I103-D122) were recognized by three out of nine sera. CONCLUSIONS/SIGNIFICANCE: This is the first reported 3D structure of an Anisakis allergen. Magnesium ion binding and structural resemblance to Calmodulin, suggest some putative functions for SXP/RAL-2 proteins. Furthermore, the IgE/IgG4 binding regions of Ani s 5 were identified as segments localized on its surface. These data will contribute towards a better understanding of the interactions that occur between immunoglobulins and allergens and, in turn, facilitate the design of novel diagnostic tests and immunotherapeutic strategies.

Cross-reactivity between Anisakis spp. and wasp venom allergens.

BACKGROUND: Anisakiasis is caused by the consumption of raw or undercooked fish or cephalopods parasitized by live L3 larvae of nematode Anisakis spp. Larvae anchor to stomach mucosa releasing excretion/secretion products which contain the main allergens. It has been described that nematode larvae release venom allergen-like proteins among their excretion/secretion products. We investigated potential cross-reactivity between Anisakis and wasp venom allergens. METHODS: Two groups of 25 patients each were studied: wasp venom- and Anisakis-allergic patients. Sera from patients were tested by ImmunoCAP, dot-blotting with recombinant Anisakis allergens and ADVIA-Centaur system with Hymenoptera allergens. Cross-reactivity was assessed by IgE immunoblotting inhibition assays. Role of cross-reactive carbohydrate determinants (CCDs) was studied by inhibition with bromelain and periodate treatment. RESULTS: A total of 40% of wasp venom-allergic patients had specific IgE to Anisakis simplex and 20% detected at least one of the Anisakis recombinant allergens tested. Likewise, 44% of Anisakis-allergic patients had specific IgE to Vespula spp. venom and 16% detected at least one of the Hymenoptera allergens tested. Wasp venom-allergic patients detected CCDs in Anisakis extract and peptide epitopes on Anisakis allergens rAni s 1 and rAni s 9, whereas Anisakis-allergic patients only detected CCDs on nVes v 1 allergen from Vespula spp. venom. The only Anisakis allergen inhibited by Vespula venom was rAni s 9. CONCLUSIONS: This is the first time that cross-sensitization between wasp venom and Anisakis is described. CCDs are involved in both cases; however, peptide epitopes are only recognized by wasp venom-allergic patients.

Long-term nonprogressor and elite controller patients who control viremia have a higher percentage of methylation in their HIV-1 proviral promoters than aviremic patients receiving highly active antiretroviral therapy.

Several factors are involved in the control of HIV transcription/replication, including epigenetic modifications at the promoter level. Analysis of the HIV long terminal repeat (LTR) methylation status in infected patients controlling viremia is scarce. Herein, we show a higher degree of DNA methylation in the 5'-LTR of long-term nonprogressor and elite controller (LTNP/EC) versus progressor patients and a positive correlation with time of infection, indicating a certain contribution of HIV LTR silencing in reducing the number of replicating viruses which may account for a delayed progression.

Anisakis simplex recombinant allergens increase diagnosis specificity preserving high sensitivity.

BACKGROUND: So far, the frequency of Anisakis simplex-specific IgE antibodies has been determined by skin prick tests (SPTs) and the ImmunoCAP system. These commercial methods have good sensitivity, but their specificity is poor because they use complete parasite extracts. Our aim was to determine the frequency of sensitization to A. simplex using recombinant Ani s 1, Ani s 3, Ani s 5, Ani s 9 and Ani s 10 and to evaluate these allergens for diagnosis, comparing their performance with the commercial methods. PATIENTS AND METHODS: We conducted a descriptive, cross-sectional validation study performed in an allergy outpatient hospital clinic. Patients without fish-related allergy (tolerant patients, n = 99), and A. simplex-allergic patients (n = 35) were studied by SPTs, ImmunoCAP assays and detection of specific IgE to A. simplex recombinant allergens by dot blotting. RESULTS: SPTs and ImmunoCAP assays were positive in 18 and 17% of tolerant patients, respectively. All A. simplex-allergic patients had positive SPTs and ImmunoCAP assays. Specific IgE against at least one of the A. simplex recombinant allergens tested was detected in 15% of sera from tolerant patients and in 100% of sera from A. simplex-allergic patients. Detection of at least one A. simplex recombinant allergen by dot blotting and ImmunoCAP assay using complete extract showed a diagnostic sensitivity of 100% with both methods. However, the specificity of dot blotting with A. simplex recombinant allergens was higher compared with ImmunoCAP (84.85 vs. 82.83%). CONCLUSIONS: There are 15% of tolerant patients with specific IgE against important A. simplex allergens. The recombinant allergens studied here increase the specificity of A. simplex diagnosis while keeping the highest sensitivity. A. simplex recombinant allergens should be included with A. simplex allergy diagnostic tests to improve their specificity.

Molecular characterization of human T cell leukemia virus type 1 subtypes in a group of infected individuals diagnosed in Portugal and Spain.

Over the past decade, Portugal and Spain received large numbers of immigrants from HTLV-1 endemic areas. Our aim was to investigate the diversity of subtypes circulating in these two countries and the introduction of new variants. We performed a molecular analysis of HTLV-1 strains in patients diagnosed since 1998. LTR and env proviral sequences from 26 individuals were analyzed to generate phylogenetic trees along with reference HTLV-1 subtypes from several geographic origins. Epidemiological and clinical data were recorded. Most subjects were immigrants (57.7%) from South America and Africa. All isolates belonged to the cosmopolitan A subtype. Most carried the transcontinental subgroup A, but five subjects carried subgroup D and one carried subgroup C, previously unreported in Europe. HTLV strains showed separate clusters linked to the patients' geographic origin. Although subjects with HTLV-1 infection tend not to be engaged in high-risk practices, silent dissemination of a broad diversity of HTLV-1 viruses may still occur.