RESUMO
The Schistosoma mansoni Venom Allergen-Like proteins (SmVALs) are members of the SCP/TAPS (Sperm-Coating Protein/Tpx-1/Ag5/PR-1/Sc7) protein superfamily, which may be important in host-pathogen interactions. Whole mount in situ hybridisation demonstrated a distinct expression pattern in oral and ventral suckers of adult worms for SmVAL6 and in the oesophageal gland for SmVAL7 transcripts, respectively. Additionally, immunocytochemistry analysis corroborated SmVAL7 expression in the oesophageal gland. Analysis of protein expression across the parasite's life cycle revealed that the SmVAL6 protein is upregulated in cercariae and adult male worms. Furthermore, SmVAL6 protein was identified by mass spectrometry in tegument fractions of adult worms. Finally, we speculate on possible functions of these two SmVALs at the host-parasite interface.
Assuntos
Alérgenos/biossíntese , Antígenos de Helmintos/biossíntese , Expressão Gênica , Proteínas de Helminto/biossíntese , Schistosoma mansoni/crescimento & desenvolvimento , Estruturas Animais/química , Animais , DNA de Helmintos/química , DNA de Helmintos/genética , Perfilação da Expressão Gênica , Hibridização In Situ , Masculino , Espectrometria de Massas , Dados de Sequência Molecular , Schistosoma mansoni/química , Schistosoma mansoni/genética , Análise de Sequência de DNARESUMO
BACKGROUND: Lipid transfer proteins (LTPs) are relevant allergens in certain plants. The role of the LTP of Hevea brasiliensis in the latex-fruit syndrome is widely unknown. OBJECTIVE: To study IgE reactivity with recombinant Hevea LTP in sera of fruit-allergic adults with and without natural rubber latex (NRL) allergy. METHODS: An LTP-specific complementary DNA of H brasiliensis leaves was amplified, subcloned into the pMAL expression system, and analyzed. The recombinant protein was coupled to ImmunoCAP, and the IgE-binding properties were studied in sera of 10 NRL-allergic patients without symptoms to fruit and 48 atopic patients with fruit allergy. Eleven of these 48 patients were also allergic to NRL, 14 displayed sensitization to NRL without symptoms on NRL exposure so far, and 23 had neither symptoms nor IgE antibodies to NRL. RESULTS: After expression in Escherichia coli, a soluble maltose-binding protein-rHev b 12 fusion protein was isolated and coupled to ImmunoCAP to determine rHev b 12 specific IgE reactivity. rHev b 12 specific IgE binding was found in 3 fruit-allergic patients with NRL sensitization (0.68, 0.88, and 0.96 kU/L) and in 3 fruit-allergic patients without NRL sensitization (1.58, 2.25, and 2.27 kU/L). The remaining 52 serum samples and all maltose-binding protein control test results were negative (< 0.35 kU/L). CONCLUSIONS: In these patients, rHev b 12 specific IgE reactivity seems to result from common cross-reactive epitopes with some of the fruit LTPs tested and underscores only an involvement in co-recognition. No clinical relevance of IgE binding to the LTP of H brasiliensis in association with NRL allergy was detected.
Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Proteínas de Transporte/imunologia , Hipersensibilidade Alimentar/imunologia , Frutas/imunologia , Imunoglobulina E/imunologia , Proteínas de Plantas/imunologia , Adolescente , Adulto , Idoso , Alérgenos/biossíntese , Reações Antígeno-Anticorpo/imunologia , Antígenos de Plantas/biossíntese , Ligação Competitiva/imunologia , Proteínas de Transporte/biossíntese , Criança , Reações Cruzadas/imunologia , Feminino , Humanos , Hipersensibilidade ao Látex/imunologia , Masculino , Pessoa de Meia-Idade , Proteínas de Plantas/biossíntese , Proteínas Recombinantes de Fusão/imunologiaRESUMO
Allergenic extracts were produced from Drechslera (Helminthosporium) monoceras biomass cultured by solid-state fermentation using wheat bran as the substrate. The main fermentation variables were selected by statistical design, and the optimized biomass yield (1.43 mg/[g of dry substrate d]) was obtained at pH 9.5 and 45.8% moisture. The allergenic extracts were produced from crude extract by protein precipitation and polyphenol removal. Proteins in the range of 16-160 kDa were identified in the extracts. Their reactions in patients were characterized by in vivo cutaneous tests (positive in 40% of the atopic patients) and by dot-blotting assays.
Assuntos
Alérgenos/biossíntese , Helminthosporium/imunologia , Alérgenos/química , Alérgenos/isolamento & purificação , Biomassa , Intervalos de Confiança , Fermentação , Helminthosporium/crescimento & desenvolvimento , Helminthosporium/fisiologia , Concentração de Íons de Hidrogênio , CinéticaAssuntos
Alérgenos/biossíntese , Alérgenos/fisiologia , Alérgenos/genética , Dermatite Alérgica de Contato/complicações , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/fisiopatologia , Dermatite Alérgica de Contato/imunologia , Hipersensibilidade/fisiopatologia , Hipersensibilidade/genéticaRESUMO
Proteins in commercial latex products, derived from the rubber tree Hevea brasiliensis, cause anaphylaxis in susceptible individuals, especially health care workers and children with spina bifida. To identify latex allergens, we utilized IgE from the serum of a latex-allergic health care worker to screen a cDNA library from Hevea latex. The identified cDNA clone, cDNA Hev b 5, encodes an open reading frame of 163 peptide residues. Hybridization analysis of cDNA Hev b 5 with RNA extracted from Hevea tissue indicates that the full-length transcript is about 1000 bases. The nucleotide and deduced protein sequences have significant homology to sequences from kiwi and potato, which are known to cause allergic reactions in some latex-allergic patients. Fifty-six percent of spina bifida patients and 92% of health care workers with latex allergy have IgE specific to the protein encoded by cDNA Hev b 5. A monoclonal antibody raised from a mouse immunized with Hev b 5 binds to a protein in Hevea latex with an Mr identical to that of the expressed and cleaved recombinant protein. Taken together, these results establish that the antigen Hev b 5 contains a major epitope for IgE-mediated reactions to H. brasiliensis latex products.