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Biomedical subjects

M Lombardero

Publications and source records attributed to M Lombardero.

At least 19 recordsLinked to original sources
PubMed2004

Cloning and expression of a major allergen from Cupressus arizonica pollen, Cup a 3, a PR-5 protein expressed under polluted environment.

BACKGROUND: This paper describes the cloning and expression of the Cupressus arizonica pollen protein Cup a 3. In addition, we present its modulation under polluted environmental conditions. Species of the Cupressaceae family are important because of their high sensitization prevalence. METHODS: Cup a 3 cloning is based on the sequence of the homologous protein Jun a 3. Cup a 3 was expressed with good yield in the methylotropic yeast Pichia pastoris. RESULTS: Recombinant Cup a 3 (rCup a 3) contains 199 amino acids, 10 potential phosphorylation sites and no glycosylation sites. By immunoblot 63% of cypress allergic patients had specific immunoglobulin E antibodies against rCup a 3 (n = 104). This major allergen is homologous to members of the pathogenesis-related proteins (PR-5 group) and contributes to the overall allergenicity of C. arizonica pollen. Our results show that the increased expression of Cup a 3 is dependent on the pollution in the area where the pollen has been collected, being higher under polluted conditions. CONCLUSIONS: Cup a 3 is a PR-5 protein derived from C. arizonica pollen. The expression of the protein under polluted conditions has a direct incidence on the pollen allergenicity, as has been demonstrated by skin tests and Radioallergosorbent test inhibition.

Adult↗
PubMed2004

Respiratory allergy to peach leaves and lipid-transfer proteins.

BACKGROUND: Several lipid-transfer proteins (LTPs) have been identified as important food allergens, especially in fruits of the Rosaceae family. The major peach (Prunus persica) allergen has been identified, sequenced and designated Pru p 3. OBJECTIVE: To present Pru p 3 as an aeroallergen able to induce occupational asthma. METHODS: A thorough investigation was performed in a fruit grower with occupational asthma. Skin prick-prick tests with peach leaves and prick tests with perennial respiratory allergens and pollens, fruits and peach leaf extracts were done. Serum-specific IgE was tested for peach leaf, peach fruit, peach skin and respiratory allergens that were positive in skin prick tests. Specific bronchial provocation tests (BPTs) with extracts of peach leaf were also done. Before and 24 h after the BPT, BPTs with methacholine and sputum induction were done. The IgE reactivity pattern to peach leaf and fruit extracts and to Pru p 3 was identified by using SDS-PAGE and immunoblotting. Blotting inhibition of peach leaf extract by Pru p 3 was also performed. The putative allergen was quantified in leaf and fruit skin extracts with ELISA based on an anti-Pru p 3 antibody. RESULTS: Skin tests were positive for peach leaf and fruit. The BPT was positive, with immediate and delayed response. This test induced a decrease in PD20 (dose of agonist that induces a 20% fall in FEV1) methacholine and an increase in eosinophils and eosinophil cationic protein in sputum. Peach leaf extract contained concentrations of Pru p 3 similar to those found in peach skin. Specific IgE immunodetection showed that patient's sera reacted with Pru p 3, and with a single major band from the peach leaf extract fully inhibited by Pru p 3. CONCLUSION: Pru p 3 from peach leaves can act as a respiratory allergen and cause occupational rhinoconjunctivitis and asthma.

Adult↗
PubMed2003

Limpet anaphylaxis: cross-reactivity between limpet and house-dust mite Dermatophagoides pteronyssinus.

BACKGROUND: Limpet is a mollusc that is frequently found along the shores of warm seas. Few allergic reactions to limpet have been described, and cross-reactivity with house-dust mites has not been established. METHODS: We report five patients with anaphylactic reactions due to limpet ingestion. A limpet extract was prepared and skin prick tests (SPT), radioallergosorbent assays (RAST), sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and IgE-immunoblotting were performed. In order to evaluate cross-reactivity, an immunoblotting inhibition assay with Dermatophagoides pteronyssinus was also done. RESULTS: All patients were asthmatics sensitized to house-dust mites. In each case, severe bronchospasm was evidenced, and three required mechanical ventilation. Positive SPT with limpet extract was found in the four patients tested. RAST showed specific IgE on each patient's sera. Immunoblotting showed several allergenic fractions with a wide molecular weight range (15-250 kDa). D. pteronyssinus inhibited IgE-binding molecules above 50 kDa in the limpet extract, particularly one molecule of 75 kDa. CONCLUSIONS: We describe five patients with IgE-mediated limpet allergy. Severe bronchospasm was the most important symptom. Cross-reactivity with D. pteronyssinus was demonstrated.

Adult↗
PubMed2002

Cross-reactivity between Platanus pollen and vegetables.

BACKGROUND: Several associations have been described between tree and plant pollens and certain foods. The objective of this study is to verify whether there is cross-reactivity between Platanus pollen and vegetable origin foods. METHODS: We selected 56 patients allergic to vegetable foods and subjected them to cutaneous tests with aeroallergens and vegetable foods. A statistical analysis was performed to evaluate the association of Platanus pollen with foods and with other aeroallergens. Later, a specific IgE determination was performed as well as a RAST (radioallergosorbent) inhibition experiment, to verify the existence of cross-reactivity in vitro. RESULTS: In the cutaneous tests we found a positive correlation between Platanus pollen and hazelnut, peanut, banana and celery. The results of the RAST inhibition experiment indicate an important cross-reactivity between the pollen of Platanus acerifolia and hazelnut and banana fruit, and an intermediate cross-reactivity with celery and peanut. CONCLUSION: We have described an association between the pollen of the Platanus tree and some vegetable foods such as hazelnut, banana, peanut and celery. This association could be explained by the in vitro IgE cross-reactivity detected.

Adolescent↗
PubMed2002

Occupational rhinoconjunctivitis and asthma in a wool worker caused by Dermestidae spp.

BACKGROUND: The family Dermestidae belongs to the order Coleoptera. Occupational allergy has been described in museum personnel. A 31-year-old male wool worker presenting rhinoconjunctivitis and asthma episodes probably linked to exposure to Dermestidae-infected wool was investigated. METHODS: Extracts prepared either from insect bodies or from dust from parasitized wool were used for skin prick testing (SPT), conjunctival and bronchial provocation tests and in vitro determinations. RESULTS: SPT and provocation tests were positive to both extracts. PEFR measurement demonstrated the association between the patient's symptoms and occupational exposure to Dermestidae. Specific IgE to both extracts was detected and immunoblotting revealed several protein bands from 5 to 200 kDa that were reactive to IgE from the patient's serum. CONCLUSIONS: Dermestidae exposure in wool workers when handling parasitized wool can be a cause of IgE-mediated rhinoconjunctivitis and asthma.

Adult↗
PubMed2002

What is the role of the hevein-like domain of fruit class I chitinases in their allergenic capacity?

BACKGROUND: Class I chitinases are the major panallergens in fruits associated with the latex-fruit syndrome. These enzymes contain an N-terminal hevein-like domain homologous to latex hevein, and a larger catalytic domain. The role of these domains in their allergenic capacity is still controversial. OBJECTIVE: We sought to evaluate the role of both domains of class I chitinases in their IgE-binding properties, using Cas s 5, the major allergen from chestnut, as a model. METHODS: Recombinant Cas s 5 and its deleted form, lacking the hevein-like domain, designated rCat, were expressed in Pichia pastoris using the pPIC 9 vector. Both recombinant products were purified from the supernatants of transformed yeast cultures by gel-filtration and cation-exchange chromatography. The isolated proteins were characterized by N-terminal sequencing, enzymatic activity and N-glycosylation tests, anti-chitinase and specific IgE immunodetection. Immunoblot, RAST and CAP inhibition assays were also performed. RESULTS: Both purified rCas s 5 and rCat showed the expected N-terminal amino acid sequences and an enzymatic activity similar to that of their natural counterparts isolated from chestnut seeds, and were strongly recognized by anti-chitinase antibodies. In contrast, only rCas s 5, but not rCat, bound specific IgE from sera of patients suffering from the latex-fruit syndrome, and fully inhibited IgE-binding to natural Cas s 5 in immunoblot inhibition assays. Latex hevein also exerted a strong immunoblot inhibition of IgE-binding to chestnut Cas s 5. RAST and CAP inhibition using whole chestnut extract on the solid phase, rendered inhibition levels around 70-90% for rCas s 5 and 60% for rCat, in contrast to the immunoblotting results. CONCLUSIONS: Recombinant Cas s 5 behaves like natural Cas s 5 in IgE-binding assays in vitro. The hevein-like domain of allergenic class I chitinases seems to include all their main IgE-binding epitopes when tested by immunodetection and immunoblot inhibition experiments. RAST and CAP inhibition assays, on the contrary, suggest that relevant epitopes are also harboured in the catalytic domain of these allergens.

Adult↗