PubMed · 9198751
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
J Bousquet, F B Michel, H J Malling. 1997-06-26. Immunotherapy for asthma.. https://pubmed.ncbi.nlm.nih.gov/9198751/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
The effect of heat treatment on the IgE binding ability of beta-lactoglobulin, as pure protein or in whole milk, was studied by inhibition of IgE antibody binding using FEIA-CAP inhibition. A slight but significant decreased IgE binding was seen between unheated and heat-treated beta-lactoglobulin solution at 74 degrees C (IC(50) = 2.03 and 3.59 microg/mL, respectively, p = 0.032). A more pronounced decrease was found at 90 degrees C with an IC(50) of 8.45 microg/mL (p = 0.014). The inhibition of IgE binding of milk after heat treatment at 90 degrees C was also significantly decreased (p = 0.007). However, at all heat treatments, a similar total amount of IgE antibodies could be inhibited at a sufficiently high concentration of beta-lactoglobulin. The inhibiting ability of beta-lactoglobulin was significantly impaired in some fermented acidified milk products such as yogurt as compared to that in nonfermented milk (p < 0.001). There was only a small difference of IgE binding between the native forms of genetic variants A and B.
Trypsin inhibitors are pathogenesis-related (PR) proteins, which play an important role in the plant defense mechanism against insects and pathogens. Peanut trypsin inhibitors are low molecular mass seed storage proteins. Like peanut allergens, they are stable to acid and heat, resistant to digestion, and can have a negative impact on human health. In peanut, five Bowman-Birk trypsin inhibitors (BBTI) have been isolated and amino acid sequences published. However, to date, no peanut BBTI sequence is available at both the cDNA and the genomic levels. The objectives of this investigation were (i) to synthesize degenerate oligonucleotides based on conserved regions of published amino acid sequences of BBTI, BII, and BIII; (ii) to isolate, sequence, and analyze at least one positive peanut trypsin inhibitor cDNA clone using the synthesized (32)P-labeled oligonucleotides as probes; and (iii) to determine its trypsin inhibitory activity. Thirty-two degenerate oligonucleotides DNA primers of 24 nucleotides each were synthesized based on the published amino acid sequences of peanut BBTI, and two were selected as probes to screen a peanut Lambda gt 11 cDNA library. Three putative positive clones were isolated, purified, and subcloned, and one was sequenced. Sequence analysis revealed a partial cDNA clone of 643 bp with a start codon. This clone shares 93 and 96% nucleotide sequence homology with peanut allergens Ara h 3 and Ara h 4 cDNA clones, respectively. A trypsin inhibitor assay revealed that peanut allergen Ara h 3 has a trypsin inhibitory activity of 11 238 TIA/mg protein. We concluded that peanut allergen Ara h 3 may also function as a trypsin inhibitor.
In this study, we constructed particles applicable for oral immunotherapy of type I allergy by protecting allergens from digestion and supporting intestinal antigen uptake. Therefore, birch-pollen allergens were entrapped in poly(d,l-lactic-co-glycolic acid) microspheres by spray-drying rendering microspheres with a main population of 1-3microm. Microspheres were further coated with wheat germ agglutinin (WGA) to target enterocytes. Coating with WGA did not alter the surface characteristics of the microspheres as demonstrated in scanning electron microscopy. Binding of WGA was specific and could be inhibited by chitotriose to 14.7+/-6.9%. Comparable amounts of allergen were released from both particle-types with 46.3+/-1.7% and 44.5+/-2.6% during 21 days. Simulating gastric digestion in vitro, antigenicity of allergens entrapped in WGA-microspheres was preserved to 59.8+/-1.5% even after 2h. Feedings of BALB/c mice with WGA-microspheres induced higher levels of allergen-specific IgG-levels than gavages of uncoated microparticles or naked protein. Thus, we conclude that WGA-microspheres are suitable vehicles for oral delivery and mucosal targeting due to lectin-mediated bioadhesion.