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1.
Article in English | MEDLINE | ID: mdl-39002946

ABSTRACT

INTRODUCTION: Patient safety is paramount in providing quality healthcare and constitutes a global concern for healthcare systems. Radioiodine treatment to patients with well-differentiated thyroid cancer is not without risks. The aim of this study is to identify, evaluate and mitigate the risks associated with this procedure. MATERIALS AND METHODS: A single-centre descriptive study was conducted in which risk management was carried out by establishing a risk map using FMEA methodology. RESULTS: Based on the process map 6 sub-processes and 23 failure modes in the three phases of the treatment process were analysed. According to risk priority number (RPN), the sub-process with the highest risk was administrative management (RPN 82), followed by treatment per se and post-treatment imaging (both with RPN 70). An overall process RPN of 300 (156 pre-treatment, 74 treatment and 70 post-treatment) was obtained. Failures directly related to the patient pose a high risk. The implementation of verification systems, performing tasks earlier and providing quality medical information are the most relevant preventive measures to be implemented. CONCLUSIONS: The application of the FMEA methodology in the risk management for radioiodine treatment is a valuable tool for improving the quality and safety of this process. The risk map has been able to identify failures at different stages, assess their causes and effects, prioritise the risks identified and implement preventive and corrective measures that can be monitored, ensuring the effectiveness of the actions taken.

2.
Sci Rep ; 9(1): 15170, 2019 10 23.
Article in English | MEDLINE | ID: mdl-31645629

ABSTRACT

Severe equine asthma (sEA), which closely resembles human asthma, is a debilitating and performance-limiting allergic respiratory disorder which affects 14% of horses in the Northern Hemisphere and is associated with increased allergen-specific immunoglobulin E (IgE) against a range of environmental proteins. A comprehensive microarray platform was developed to enable the simultaneous detection of allergen-specific equine IgE in serum against a wide range of putative allergenic proteins. The microarray revealed a plethora of novel pollen, bacteria, mould and arthropod proteins significant in the aetiology of sEA. Moreover, the analyses revealed an association between sEA-affected horses and IgE antibodies specific for proteins derived from latex, which has traditionally been ubiquitous to the horse's environment in the form of riding surfaces and race tracks. Further work is required to establish the involvement of latex proteins in sEA as a potential risk factor. This work demonstrates a novel and rapid approach to sEA diagnosis, providing a platform for tailored management and the development of allergen-specific immunotherapy.


Subject(s)
Allergens/blood , Antigens/blood , Asthma/diagnosis , Asthma/veterinary , Horses/blood , Horses/immunology , Serologic Tests , Animals , Asthma/blood , Discriminant Analysis , Least-Squares Analysis
3.
Ultrasound Obstet Gynecol ; 49(6): 744-750, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27363854

ABSTRACT

OBJECTIVE: To assess the effectiveness of laser surgery in fetuses with a cystic lung lesion with systemic arterial blood supply (hybrid lung lesion) at risk of perinatal death. METHODS: A cohort of five consecutive fetuses with a large hybrid lung lesion associated with hydrops and/or pleural effusion with severe lung compression was selected for percutaneous ultrasound-guided fetal laser ablation of the feeding artery (FLAFA) before 32 weeks' gestation in a single tertiary national referral center in Queretaro, Mexico. The primary outcomes were survival and need for postnatal surgery. RESULTS: FLAFA was performed successfully in all cases at a median gestational age of 24.9 (range, 24.4-31.7) weeks. After fetal intervention, dimensions in both lungs increased and fluid effusions resolved in all cases. All cases were delivered liveborn at term at a median gestational age of 39.6 (range, 38.0-39.7) weeks, without respiratory morbidity or need for oxygen support, resulting in perinatal survival of 100%. During follow-up, three (60%) cases showed progressive regression of the entire lung mass and did not require postnatal surgery, whereas in two (40%) cases a progressive decrease in size of the mass was observed but a cystic portion of the lung mass persisted and postnatal lobectomy was required. CONCLUSION: In fetuses with large hybrid lung lesions at risk of perinatal death, FLAFA is feasible and could improve survival and decrease the need for postnatal surgery. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Subject(s)
Cystic Adenomatoid Malformation of Lung, Congenital/surgery , Fetal Diseases/surgery , Lung Diseases/diagnosis , Arteries/surgery , Cohort Studies , Cystic Adenomatoid Malformation of Lung, Congenital/complications , Cystic Adenomatoid Malformation of Lung, Congenital/diagnostic imaging , Cystic Adenomatoid Malformation of Lung, Congenital/physiopathology , Female , Fetal Diseases/diagnostic imaging , Fetal Diseases/physiopathology , Fetal Therapies , Gestational Age , Humans , Laser Therapy , Lung Diseases/complications , Lung Diseases/congenital , Lung Diseases/diagnostic imaging , Lung Diseases/physiopathology , Lung Diseases/surgery , Mexico , Pregnancy , Prospective Studies , Treatment Outcome , Ultrasonography, Interventional , Ultrasonography, Prenatal
4.
Vet Immunol Immunopathol ; 167(3-4): 171-7, 2015 Oct 15.
Article in English | MEDLINE | ID: mdl-26163936

ABSTRACT

Insect bite hypersensitivity (IBH) is a seasonal recurrent skin allergy of horses caused by IgE-mediated reactions to allergens present in the saliva of biting insects of the genus Culicoides, and possibly also Simulium and Stomoxys species. In this work we show that protein microarrays containing complex extracts and pure proteins, including recombinant Culicoides allergens, can be used as a powerful technique for the diagnosis of IBH. Besides the obvious advantages such as general profiling and use of few microliters of samples, this microarray technique permits automation and allows the generation of mathematical models with the calculation of individual risk profiles that can support the clinical diagnosis of allergic diseases. After selection of variables on influence on the projection (VIP), the observed values of sensitivity and specificity were 1.0 and 0.967, respectively. This confirms the highly discriminatory power of this approach for IBH and made it possible to attain a robust predictive mathematical model for this disease. It also further demonstrates the specificity of the protein array method on identifying a particular IgE-mediated disease when the sensitising allergen group is known.


Subject(s)
Horse Diseases/diagnosis , Horse Diseases/immunology , Hypersensitivity/veterinary , Insect Bites and Stings/veterinary , Allergens , Animals , Case-Control Studies , Ceratopogonidae/immunology , Diagnosis, Computer-Assisted/veterinary , Female , Horses , Hypersensitivity/diagnosis , Hypersensitivity/immunology , Immunoglobulin E/blood , Insect Bites and Stings/diagnosis , Insect Bites and Stings/immunology , Male , Mathematical Concepts , Models, Immunological , Protein Array Analysis , Skin/immunology
5.
J Fish Biol ; 86(3): 1153-62, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25583211

ABSTRACT

The level of genetic homogeneity and demographic history of the Monterey Spanish mackerel Scomberomorus concolor was assessed by analyses using sequences of the mitochondrial (mt)DNA-control region of samples from the two oceanographic regions of the Gulf of California in order to define the stock structure for this exploited vulnerable species. The data were consistent with a single homogeneous population and revealed the hallmark of fluctuations in population size; these fluctuations appear to have occurred during glacial events of the middle to late Pleistocene, which may in turn be related to the colonization and expansion of S. concolor populations in the gulf.


Subject(s)
Genetics, Population , Perciformes/genetics , Animals , DNA, Mitochondrial/genetics , Haplotypes , Mexico , Phylogeography , Population Density , Population Dynamics , Sequence Analysis, DNA
6.
Allergy ; 68(1): 74-83, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23137012

ABSTRACT

BACKGROUND: Lipids are required for mice sensitization to Ber e 1, Brazil nut major allergen. Here, we characterized different lipid fractions extracted from Brazil nuts and the lipid-binding ability of Ber e 1. Further, we determined their in vivo ability to induce Ber-specific anaphylactic antibodies and the role of invariant natural killer T (iNKT) cells in this process. METHODS: Wild-type (WT) and iNKT cell-deficient mice were sensitized with Ber e 1 and specific lipid fractions, and anaphylactic antibodies were measured by enzyme-linked immunosorbent assay (ELISA) and passive cutaneous anaphylaxis (PCA). The lipid-binding characteristic of Ber e 1 (Ber) was established by using fluorescent probes and (15) N-labeled NMR. In vitro production of IL-4 was determined in Ber/lipid C-stimulated mouse iNKT cells and human T-cell lines containing NKTs primed with CD1d+C1R transfectants by flow cytometry and ELISA, respectively. RESULTS: Only one specific lipid fraction (lipid C), containing neutral and common phospholipids, induced Ber anaphylactic antibodies in mice. Ber e 1 has a lipid-binding site, and our results indicated an interaction between Ber e 1 and lipid C. iNKT-deficient mice produced lower levels of anaphylactic antibodies than WT mice. In vitro, Ber/lipid C-stimulated murine iNKT cells produced IL-4 but not IFN-gamma. Human T-cell lines derived from nut-allergic patients produced IL-4 to Ber/lipid C in a CD1d- and dose-dependent manner. CONCLUSION: Lipid fraction C from Brazil nut presents an essential adjuvant activity to Ber e 1 sensitization, and iNKT cells play a critical role in the development of Brazil nut-allergic response.


Subject(s)
Lipids/immunology , Natural Killer T-Cells/immunology , Nut Hypersensitivity/immunology , 2S Albumins, Plant/chemistry , 2S Albumins, Plant/immunology , Adolescent , Adult , Allergens/immunology , Animals , Antibodies/blood , Antibodies/immunology , Antigens, Plant/chemistry , Antigens, Plant/immunology , Binding Sites , Female , Humans , Hydrophobic and Hydrophilic Interactions , Lymphocyte Activation/immunology , Male , Mice , Nut Hypersensitivity/metabolism , Protein Binding , Th2 Cells/immunology , Young Adult
7.
J Immunol Methods ; 382(1-2): 48-57, 2012 Aug 31.
Article in English | MEDLINE | ID: mdl-22580759

ABSTRACT

The sera of a retrospective cohort (n=41) composed of children with well characterized cow's milk allergy collected from multiple visits were analyzed using a protein microarray system measuring four classes of immunoglobulins. The frequency of the visits, age and gender distribution reflected real situation faced by the clinicians at a pediatric reference center for food allergy in São Paulo, Brazil. The profiling array results have shown that total IgG and IgA share similar specificity whilst IgM and in particular IgE are distantly related. The correlation of specificity of IgE and IgA is variable amongst the patients and this relationship cannot be used to predict atopy or the onset of tolerance to milk. The array profiling technique has corroborated the clinical selection criteria for this cohort albeit it clearly suggested that 4 out of the 41 patients might have allergies other than milk origin. There was also a good correlation between the array data and ImmunoCAP results, casein in particular. By using qualitative and quantitative multivariate analysis routines it was possible to produce validated statistical models to predict with reasonable accuracy the onset of tolerance to milk proteins. If expanded to larger study groups, the array profiling in combination with the multivariate techniques show potential to improve the prognostic of milk allergic patients.


Subject(s)
Immune Tolerance/immunology , Immunoglobulin E/immunology , Milk Hypersensitivity/immunology , Milk Proteins/immunology , Milk/immunology , Protein Array Analysis/methods , Adolescent , Animals , Child , Child, Preschool , Female , Humans , Immunoglobulin E/blood , Male , Milk/chemistry , Multivariate Analysis , Predictive Value of Tests , Young Adult
8.
J Immunol Methods ; 364(1-2): 21-32, 2011 Feb 01.
Article in English | MEDLINE | ID: mdl-20974146

ABSTRACT

Existing food immunoglobulin (Ig) tests require large volumes of serum, are limited to one immunoglobulin class, are not amenable to high throughput analysis and only give a limited picture of the immunological response to food antigens. Conversely a new generation of Component Resolved Diagnostic systems using pure proteins is highly specific and totally dependent on the availability of the protein in its recombinant or natural origin form. Here we demonstrate a proof-of-concept of a microarray test based on protein extracts of food components. Our approach relies on innovations on three different fronts: the novelty of using arrayed food samples sequentially extracted with detergent and chaotropic agents, the ability to measure four different Ig classes simultaneously and the ability to analyse the generated data via a suitable bioinformatics/statistical analysis interface. This approach combines high numerical power of microarrays with automation, high throughput analysis and enables detailed investigation of the Ig profiles to food antigens. The prototype shown contains extracts of approximately 350 food ingredients that cover most of the food products found in the UK. Here we showed that the use of a sequential extraction technique to solubilise and then denature food samples has its benefits in the assessment of variations in antigenicity when tested with human sera. A patient dependent degree of class specificity was observed with human sera (IgG specificity correlates well with IgA>IgM>>>>>IgE). Besides generating a simultaneous profile for IgA, IgM, IgG and IgE the array system has shown good discrimination between challenge responders in atopic and non-atopic individuals. Poly- and mono-specific IgE responders were easily identified. The mathematical modelling of specific IgE content showed good correlations when compared with established IgE antibody testing assay (UniCAP). Although in its proof-of-principle stages, the immune profiling technique described here has the potential to provide unique insights into exposure/sensitization and establish relationships between specific immunoglobulin classes and subclasses against food protein antigens. In further developments, the immune profiling technique could also be extended to other related areas such as parasite and bacterial gut infection. Full analyses of large longitudinal and retrospective clinical trials are on going to determine the positive and negative predictive values of the technique.


Subject(s)
Allergens/metabolism , Food Hypersensitivity/diagnosis , Immunoglobulins/blood , Protein Array Analysis/methods , Proteins/metabolism , Allergens/immunology , Animals , Cell Extracts , Computational Biology , Electronic Data Processing , Food Hypersensitivity/blood , Food Hypersensitivity/immunology , High-Throughput Screening Assays , Humans , Models, Theoretical , Predictive Value of Tests , Proteins/immunology , Sensitivity and Specificity , United Kingdom
9.
Actas Esp Psiquiatr ; 38(5): 285-94, 2010.
Article in English, Spanish | MEDLINE | ID: mdl-21117003

ABSTRACT

Huntington's disease is the most frequent neurodegenerative disease with a prevalence of fewer than 10 cases per 10,000 inhabitants; the juvenile form is responsible for less than 10% of all cases. Huntington's disease belongs to the group known as "triad syndromes," which evolve with cognitive, motor and neuropsychiatric manifestations. Around 30% of patients debut with behavioral symptoms, which are a major challenge for management by patients, families, and caregivers. Huntington's disease (HD) is reviewed and a case of juvenile onset is reported in this article. The characteristics of juvenile-onset Huntington's disease (HD) differ from those of adult-onset HD, as chorea does not occur, although bradykinesia, dystonia, and signs of cerebellar disorder, such as rigidity, are present, frequently in association with convulsive episodes and psychotic manifestations.


Subject(s)
Huntington Disease , Adolescent , Female , Humans , Huntington Disease/diagnosis , Huntington Disease/therapy
10.
Actas Esp Psiquiatr ; 38(2): 87-93, 2010.
Article in English | MEDLINE | ID: mdl-20976637

ABSTRACT

Transcranial magnetic stimulation (TMS) is a technique is which the evidence has been confirming its efficacy. Repetitive stimulation (rTMS) of the left prefrontal dorsolateral (LPFDL) area with frequencies between 10 and 20 Hz has been shown to be effective in major depression. This article presents the prospective analysis of the treatments performed using TMS on LPFDL at 20 Hz with an intensity of 70% in a protocol of 10 sessions on 107 patients (41 male and 61 female) due to drug treatment resistant depressive symptoms in different conditions. The patients had previously undergone two psychopharmacological attempts with adequate dosage and time, who had been considered candidates for electroconvulsive therapy (ECT) if they did not respond to any conventional treatment. A total of 62.7% had mood disorder, 13.1% obsessive-compulsive disorders (OCT), 7.5% cognitive disorders, 4.7% personality disorders and 3.7% were psychiatric disorders. Mean age of the group was 49.98 years (SD = 17.09). The global results showed that the TMS provided some degree of improvement in 48.6%, although only half, that is 24.3%, maintained it beyond week 12. Efficacy by diagnoses showed a significant difference in favor of affective disorders. In the case of bipolar disorders in the depressive phase, there was improvement in 88.9%, which was maintained in 66.7% of the patients treated. No differences in efficacy were found within each one of the groups diagnosed based on gender, age or presence of personality disorders. The efficacy of the ECT was similar to the TMS in the group in which it had to be applied in comparison with the general group. New studies are proposed with the inclusion of the TMS for resistant-depression treatment protocols in a step prior to the ECT and even before all the drug treatments had been attempted, combining it with them for their potentiation.


Subject(s)
Depressive Disorder/therapy , Transcranial Magnetic Stimulation , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies , Retrospective Studies , Young Adult
11.
Mol Phylogenet Evol ; 57(3): 1209-18, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20971198

ABSTRACT

Pelagic fish that are distributed circumtropically are characterised by a low population structure level as a result of a high capacity for dispersion and large population sizes. Nevertheless, historical and contemporary processes, including past demographic and/or range expansions, secondary contact, dispersal, gene flow, and the achievement of large effective population sizes, may play a part in the detection of divergence signals, especially in the case of tropical pelagic species, whose distribution range depends strongly on the sea surface temperature. The connectivity and historical demography of Atlantic, Indian, Pacific and Mediterranean populations of dolphinfish (Coryphaena hippurus) was studied using partial sequences of the mitochondrial DNA NADH dehydrogenase subunit 1 (ND1). AMOVA analyses revealed significant inter-oceanic divergence with three phylogroups located in the Indo-Pacific, Eastern Atlantic, and Mediterranean Sea, the last one being the most divergent. However, it was not possible to clearly observe any genetic differentiation between the Indo-Pacific and Atlantic populations, as has been reported for most tropical pelagic species of tuna and billfishes. This supports the assumption of recent dispersal among basins facilitated by the actual continuous distribution of dolphinfish populations. Moreover, the lack of a divergence signal for populations separated by the Panamanian Isthmus reveals that genetic drift does not exert a strong influence on tropical pelagic species with large effective population sizes.


Subject(s)
Genetics, Population , Perciformes/genetics , Phylogeny , Phylogeography , Animals , Bayes Theorem , DNA, Mitochondrial/genetics , Genetic Variation , Haplotypes , Likelihood Functions , Mediterranean Sea , Models, Genetic , Perciformes/classification , Population Density , Sequence Alignment , Sequence Analysis, DNA
12.
Ann Rheum Dis ; 67(4): 518-23, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17704067

ABSTRACT

OBJECTIVE: In countries where parasitic infections are endemic, autoimmune disease is relatively rare, leading to the hypothesis that parasite-derived immunomodulators may protect against its development. Consistent with this, we have previously demonstrated that ES-62, a 62 kDa phosphorylcholine (PC)-containing glycoprotein that is secreted by filarial nematodes, can exert anti-inflammatory action in the murine collagen-induced arthritis (CIA) model and human rheumatoid arthritis-derived synovial tissue cultures. As a first step to developing ES-62-based drugs, the aim of this study was to determine whether the PC-moiety of ES-62 was responsible for its anti-inflammatory actions. METHODS: We compared the anti-inflammatory activity of a PC-free form of recombinant ES-62 (rES-62) and a synthetic PC-ovalbumin conjugate (OVA-PC) with that of native ES-62 in the CIA model and synovial tissues from patients with rheumatoid arthritis. RESULTS: The anti-inflammatory actions of ES-62 in CIA appear to be dependent on the PC moiety as indicated by the reduction in severity of disease and also suppression of collagen-specific T helper 1 cytokine production observed when testing OVA-PC, but not rES-62. Interestingly, the anti-inflammatory activity of PC did not correlate with a reduction in anti-collagen IgG2a levels. Also, the ES-62-mediated suppression of interferon-gamma from human patient tissues could be mimicked by OVA-PC but not rES-62 or ovalbumin. CONCLUSIONS: In countries where filariasis is endemic the reduced detection of inflammatory diseases, such as rheumatoid arthritis may be because of the anti-inflammatory action of the PC moieties of ES-62. PC may thus provide the starting point for the development of novel, safe immunomodulatory therapies.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Arthritis, Experimental/drug therapy , Arthritis, Rheumatoid/immunology , Helminth Proteins/therapeutic use , Immunologic Factors/therapeutic use , Phosphorylcholine/immunology , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/immunology , Arthritis, Experimental/immunology , Cells, Cultured , Cytokines/blood , Helminth Proteins/chemistry , Helminth Proteins/immunology , Humans , Immunoglobulin G/blood , Immunologic Factors/chemistry , Immunologic Factors/immunology , Inflammation Mediators/blood , Male , Mice , Mice, Inbred DBA , Recombinant Proteins/chemistry , Recombinant Proteins/immunology , Recombinant Proteins/therapeutic use , Synovial Membrane/immunology , Tissue Culture Techniques
13.
Clin Exp Allergy ; 37(12): 1854-62, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18028099

ABSTRACT

BACKGROUND: Protein microarray (PM) is a powerful alternative to costly or labour-intensive diagnostic for the large-scale detection of allergen-specific IgE. In this study, we established a proof-of-concept that coupling the diversity of protein array with the biological output of basophilic cells is a feasible proposition. METHOD: Human basophils purified from the peripheral blood of healthy donors were stripped, re-sensitized with the serum or IgE preparation to be tested, and incubated with manually spotted protein array chips (FAST slides). The basophilic cell lines KU-812 and RBL-703/21 likewise sensitized were compared with peripheral blood basophils by the same approach. Purified basophils or other basophilic cells were incubated with FAST slides for various periods of time, washed, and cell binding was visualized by light microscopy. Basophil activation, indicating the effective cross-linking of IgE by allergens, was monitored via up-regulation of basophil activation surface marker (CD 63). RESULTS: Purified stripped peripheral basophils, re-sensitized with the serum of a grass pollen-allergic patient, displayed strong binding to anti-IgE antibody and grass pollen extract with relatively low unspecific binding. Similar results were obtained with RBL-703/21, which may be a good replacement for peripheral basophils to avoid the costly, cumbersome and time-consuming basophil purification. CONCLUSION: Our data suggest that coupling the diversity of a PM approach with the potential functionality and biological activity of a cell-based test is feasible and may result in a new system to detect allergic sensitization.


Subject(s)
Basophils/immunology , Basophils/metabolism , Hypersensitivity/immunology , Hypersensitivity/metabolism , Protein Array Analysis/methods , Allergens/immunology , Allergens/metabolism , Animals , Basophils/cytology , Cell Differentiation/immunology , Cell Line , Humans , Rats , Time Factors
14.
Clin Exp Allergy ; 37(4): 582-91, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17430356

ABSTRACT

BACKGROUND: Lipids, particularly bacterial lipopolysaccharide, can impact on immune responses to proteins, with low doses enhancing type 2 responses. OBJECTIVE: We have examined the influence of natural plant lipid extracts on antibody responses provoked in mice by recombinant Ber e 1, the major allergen in Brazil nuts. METHODS: BALB/c strain mice were immunized (by intraperitoneal injection) with natural or recombinant Ber e l produced in Pichia pastoris and admixed with various lipid fractions isolated from Brazil nuts. Serum samples were analysed for specific IgE antibody by homologous passive cutaneous anaphylaxis assay and for IgG by enzyme-linked immunosorbant assay. RESULTS: Exposure to recombinant (lipid-free) Ber e 1 alone failed to induce detectable IgG or IgE antibody. Co-administration of the total lipid fraction (with reduced triglyceride levels), sterol-rich, or polar lipid fractions, resulted in marked adjuvant effects on IgG and IgE. However, the beta-sitosterol and glycolipid-rich fractions were associated with only low-level IgG antibody, and had little impact on IgE antibody production. Natural Ber e 1 containing endogenous lipids also provoked IgG and IgE antibody responses. Identical IgE and IgG antibody responses were detected regardless of whether natural or recombinant Ber e 1 was used as substrates for analyses. CONCLUSION: Endogenous Brazil nut lipids are required for the induction of optimal antibody responses to Ber e 1 in the BALB/c strain mouse. Appropriate antibody binding sites are present on both natural and recombinant forms of Ber e 1, suggesting that the impact of lipid is at the induction phase, rather than antibody recognition, and is possibly required for efficient antigen presentation.


Subject(s)
Albumins/immunology , Allergens/immunology , Lipids/immunology , Nut Hypersensitivity/immunology , Protein Precursors/immunology , 2S Albumins, Plant , Adjuvants, Immunologic , Animals , Antigens, Plant , Bertholletia/immunology , Female , Immunoglobulin E/biosynthesis , Immunoglobulin G/biosynthesis , Mice , Mice, Inbred BALB C , Plant Proteins/immunology , Recombinant Proteins/immunology
15.
Parasite Immunol ; 29(3): 127-37, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17266740

ABSTRACT

Modulation of macrophage/dendritic cell (DC) cytokine production by the filarial nematode phosphorylcholine (PC)-containing product, ES-62, is mediated by Toll-like receptor (TLR) 4 and signal transduction depends on the TLR adaptor MyD88. Intriguingly, comparison of TLR4 knock-out (ko) mice with TLR4 mutant C3H/HeJ mice indicates that ES-62 cytokine responses are not dependent on the Pro712 residue of TLR4, which is crucial for the response to bacterial lipopolysaccharide (LPS). Because other immunomodulatory effects of ES-62 have been attributed to PC we have now investigated, using PC conjugated to ovalbumin (PC-Ova), whether PC is responsible for the interaction of ES-62 with TLR4. PC-Ova mimicked the modulation of interleukin (IL)-12 production by ES-62 in a TLR4- and MyD88-dependent manner and as with native ES-62, PC-Ova effects were not dependent on Pro712. Furthermore, both native ES-62 and PC-Ova suppressed Akt phosphorylation, whereas neither altered the activation of p38 or Erk MAP kinases. To rule out any role for the ES-62 protein component, we tested a PC-free recombinant ES-62 (rES-62) generated in the yeast Pichia pastoris. Surprisingly, rES-62 also modulated IL-12 production, but in a TLR4/MyD88-independent manner. Furthermore, rES-62 strongly activated both the p38 and Erk MAP kinases and Akt. However, recent biophysical analysis suggests there are differences in folding/shape between native and rES-62 and hence data obtained with the latter should be treated with caution. Nevertheless, although our study indicates that PC is likely to be primarily responsible for the modulation of cytokine production observed with native ES-62, an immunomodulatory role for the protein component cannot be ruled out.


Subject(s)
Dendritic Cells/metabolism , Helminth Proteins/metabolism , Interleukin-12/biosynthesis , Macrophages/metabolism , Phosphorylcholine/metabolism , Toll-Like Receptor 4/metabolism , Animals , DNA Primers , Enzyme-Linked Immunosorbent Assay , Extracellular Signal-Regulated MAP Kinases/metabolism , Helminth Proteins/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Myeloid Differentiation Factor 88/metabolism , Ovalbumin , Phosphorylcholine/immunology , Phosphorylcholine/pharmacology , Pichia , Proto-Oncogene Proteins c-akt/metabolism , Reverse Transcriptase Polymerase Chain Reaction , p38 Mitogen-Activated Protein Kinases/metabolism
16.
Parasitology ; 132(Pt 2): 263-74, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16216137

ABSTRACT

The longevity of filarial nematodes is dependent on secreted immunomodulatory products. Previous investigation of one such product, ES-62, has suggested a critical role for post-translationally attached phosphorylcholine (PC) moieties. In order to further investigate this, ES-62 lacking PC was produced, using the Pichia pastoris recombinant gene expression system. Unlike parasite-derived ES-62, which is tetrameric the recombinant material was found to consist of a mixture of apparently stable tetramers, dimers and monomers. Nevertheless, the recombinant protein was considered to be an adequate PC-free ES-62 as it was recognized by existing antisera against the parasite-derived protein. However, subsequent to this, recognition of parasite-derived ES-62 by antibodies produced against the recombinant protein was found to be absent. In an attempt to explain this, recombinant ES-62 was subjected to structural analysis and was found to (i) contain 3 changes in amino acid composition; (ii) demonstrate significant alterations in glycosylation; (iii) show major differences in protein secondary structure. The effects of these alterations in relation to the observed change in immunogenicity were investigated and are discussed. The data presented clearly show that recognition by existing antibodies is insufficient proof that recombinant proteins can be used to mimic parasite-derived material in studies on nematode immunology and vaccination.


Subject(s)
Dipetalonema/immunology , Dipetalonema/physiology , Helminth Proteins/genetics , Helminth Proteins/immunology , Recombinant Proteins/immunology , Amino Acid Sequence , Animals , Circular Dichroism/methods , Cross Reactions , Dipetalonema/genetics , Electrophoresis, Polyacrylamide Gel , Female , Glycosylation , Helminth Proteins/chemistry , Helminth Proteins/metabolism , Immunoglobulin G/metabolism , Mice , Mice, Inbred BALB C , Mutagenesis, Site-Directed/methods , Phosphorylcholine/chemistry , Phosphorylcholine/metabolism , Pichia/genetics , Polymerase Chain Reaction/methods , Protein Structure, Secondary/physiology , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Time Factors , Ultracentrifugation/methods
17.
Clin Exp Allergy ; 33(8): 1147-52, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12911791

ABSTRACT

BACKGROUND: The ability of an intact protein to reach the circulatory system may be a prerequisite to allergenicity and many allergens, particularly those from plant foods, have been found to be consistently more resistant to digestion by pepsin than other proteins. OBJECTIVE: This study assessed the pepsinolytic stability of native 2S albumins from Brazil nut and sunflower seed and their recombinant versions produced in Pichia pastoris. The physicochemical stability of native and recombinant Brazil nut 2S albumins and recombinant sunflower seed 2S albumin was also assessed. The immunoreactivity of native Brazil nut 2S albumin and recombinant 2S albumins was compared using serum from patients allergic to Brazil nuts and animals immunized with native 2S albumins. METHODS: Digestibility was measured in simulated gastric fluid followed by SDS-PAGE. Circular dichroism spectra were used to analyse unfolding, as proteins were denatured by temperature, pH and guanidinium chloride. Immunoreactivity was assessed by immunoblot, RAST and ELISA. RESULTS: Brazil nut 2S albumin was significantly more resistant to proteolytic digestion than other Brazil nut proteins. It was also resistant to thermally and chemically induced denaturation. Equally high resistance to proteolytic digestion was observed with sunflower seed 2S albumin. The recombinant albumins mirrored their native counterparts in stability and immunoreactivity. CONCLUSION: The important food allergen Brazil nut 2S albumin is as stable to digestion as is sunflower seed 2S albumin, whose allergenicity has yet to be determined. The 2S albumins and their recombinant counterparts could not be easily denatured by physicochemical treatments. The results suggest that 2S albumin is the only Brazil nut protein to reach the gut immune system intact. The production of properly folded recombinant proteins will facilitate mechanistic studies as well as diagnostic testing and antigen-based therapies.


Subject(s)
Albumins/chemistry , Nuts/chemistry , Plant Proteins/chemistry , Protein Precursors/chemistry , Seeds/chemistry , 2S Albumins, Plant , Albumins/immunology , Animals , Antigens, Plant , Chemical Phenomena , Chemistry, Physical , Digestion , Drug Stability , Gastric Juice/chemistry , Guanidine/pharmacology , Helianthus/immunology , Hot Temperature , Humans , Hydrogen-Ion Concentration , Hydrolysis , Immunoglobulin E/immunology , Immunoglobulin G/immunology , Nut Hypersensitivity/blood , Nuts/immunology , Plant Proteins/immunology , Plants, Edible/immunology , Protein Denaturation , Protein Precursors/immunology , Rabbits , Recombinant Proteins/chemistry , Recombinant Proteins/immunology , Seeds/immunology
18.
Appl Microbiol Biotechnol ; 60(6): 726-32, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12664153

ABSTRACT

Genes encoding three enzymes with xylanase activity from the filamentous fungus Penicillium funiculosum are described. Two of the encoded xylanases are predicted to be modular in structure with catalytic and substrate-binding domains separated by a serine and threonine-rich linker region; the other had none of these properties and was non-modular. In order to develop P. funiculosum as a host for the secreted production of heterologous proteins, each of the xylanases was assessed for use as a carrier protein in a fusion strategy. We show that one of the modular xylanases (encoded by xynA) was an effective carrier protein but the other (encoded by xynB) and the non-modular xylanase (encoded by xynC) were not effective as secretion carriers. We show that the beta-glucuronidase (GUS) protein from Escherichia coli is secreted by P. funiculosum when expressed as an XYNA fusion but that the secreted GUS protein, cleaved in vivo from XYNA, is glycosylated and enzymatically inactive.


Subject(s)
Carrier Proteins/metabolism , Endo-1,4-beta Xylanases , Fungal Proteins/metabolism , Isoenzymes/metabolism , Penicillium/enzymology , Recombinant Fusion Proteins/metabolism , Xylosidases/metabolism , beta-Glucosidase/metabolism , Amino Acid Sequence , Binding Sites , Catalytic Domain , Cloning, Molecular , Escherichia coli/enzymology , Escherichia coli/genetics , Fungal Proteins/chemistry , Fungal Proteins/genetics , Genes, Fungal , Genes, Synthetic , Glucuronidase/metabolism , Glycosylation , Histones/genetics , Isoenzymes/chemistry , Isoenzymes/genetics , Molecular Sequence Data , Penicillium/genetics , Promoter Regions, Genetic , Protein Processing, Post-Translational , Protein Structure, Tertiary , Recombinant Fusion Proteins/genetics , Sequence Homology, Amino Acid , Transformation, Genetic , Xylan Endo-1,3-beta-Xylosidase , Xylosidases/chemistry , Xylosidases/genetics , beta-Glucosidase/chemistry , beta-Glucosidase/genetics
19.
Appl Microbiol Biotechnol ; 60(4): 455-60, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12466887

ABSTRACT

Two genes encoding histone H4 (H4.1 and H4.2) from Penicillium funiculosum have been cloned and characterised. Structurally, the histone H4.1 gene is divergently linked to the histone H3 gene and the two genes are separated by approximately 800 bp. The transcription of the histone H4.1 and H4.2 genes in P. funiculosum appears to be distinctively regulated. Histone H4.1 mRNA showed a high steady-state level during the early stages of batch culture that decreased as growth reached the stationary phase. In contrast, the expression of the histone H4.2 gene was lower than that of H4.1 throughout batch growth and increased gradually with time. In order to expand the industrial application of P. funiculosum as a host for the production of heterologous proteins, the promoter of the histone H4.1 gene was successfully used to drive the expression of an intracellular bacterial enzyme, beta-glucuronidase, and a secreted homologous enzyme, xylanase C. The constitutive secretion of xylanase C was achieved in the absence of other xylanases by batch fermentation in the presence of glucose.


Subject(s)
Glucuronidase/metabolism , Histones/genetics , Industrial Microbiology , Penicillium/genetics , Promoter Regions, Genetic , Xylosidases/metabolism , Blotting, Northern , Cloning, Molecular , Electrophoresis, Polyacrylamide Gel , Endo-1,4-beta Xylanases , Fermentation , Gene Expression Regulation, Fungal , Genetic Vectors/genetics , Glucose/metabolism , Glucuronidase/genetics , Penicillium/enzymology , Penicillium/metabolism , Xylosidases/genetics
20.
Biochem Soc Trans ; 30(Pt 6): 913-5, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12440945

ABSTRACT

Two well known 2 S albumins, Ber e 1 from brazil nut and sunflower 2 S albumin 8 (SFA-8), have been expressed in a eukaryotic system and purified. Analysis of recombinant versions of Ber e 1 and SFA-8 revealed them to be significantly more resistant to digestion by pepsin than BSA, and to be stable for up to 30 min in simulated gastric fluid. Unfolding monitored by CD indicated that both proteins were also very resistant to denaturation induced by heat and low pH. These results suggest that, although the ability of 2 S albumins to reach the circulatory system may be a prerequisite for the allergenicity of this group of proteins, stability is just one of a number of characteristics that provoke a selective immune response.


Subject(s)
Plant Proteins/chemistry , Recombinant Proteins/chemistry , 2S Albumins, Plant , Antigens, Plant , Bertholletia/metabolism , Circular Dichroism , Helianthus/metabolism , Hydrogen-Ion Concentration , In Vitro Techniques , Pepsin A/pharmacology , Plant Proteins/isolation & purification , Plant Proteins/metabolism , Serum Albumin/pharmacology , Time Factors , Ultraviolet Rays
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