Human recombinant antibody fragments specific for a rye-grass pollen allergen: Characterization and potential applications

摘要: One of the major allergens from pollen perennial rye grass (Lolium perenne), Lol pII, was used to isolate specific antibody fragments a random combinatorial library displaying large repertoire human Fab on filamentous phages. After five panning cycles recombinant pII immunotubes, phage binders were isolated and expressed as soluble molecules in Escherichia coli periplasm. The DNA sequencing clones producing antibodies with highest binding activity showed three them be identical, while one differed by two amino acid substitutions heavy chain. produced milligram amounts, affinity-purified further characterized. They bound natural allergen well one, no cross-reactivity other contained extract L. perenne. Kd=2.63 × 10−9 M, demonstrated surface plasmon resonance technique, able compete fraction serum IgE. Epitope mapping using synthetic peptides revealed that antigenic domains, located between acids 39 51 are recognized polyclonal IgE sera allergic donors. inhibited allergen. In vitro experiments whole blood subjects had blocking histamine release cells challenged Thus, recognize common epitopes, although they represent outcome different maturation and/or selection processes. Our molecular functional findings altogether indicate allergen-specific may useful for characterization structure allergens. We conclude is powerful source anti-allergen high affinity specificity. Moreover, these potentially innovative reagents treatment atopic allergy.