Comparable T-Cell activation induced by natural and recombinant allergens☆

Abstract Rationale The next generation allergy vaccines have been suggested to be recombinant major allergens. Since naturally occurring major allergens are composed of many isoforms, it is necessary to investigate if all allergic patients will benefit from treatment with a single recombinant isoform or a genetically modified hypoallergenic variant. Methods Naturally occurring isoforms, recombinant allergens and genetically modified forms of the recombinant allergens were used in assays to stimulate T-cell lines from atopic patients raised against natural purified allergens. Samples were tested for proliferation ( 3 H-thymidine) and cytokine production (IFN-gamma, IL-10, IL-5, IL-4). Results Eight nBet v 1 T-cell lines were established and all except one responded equally well to both nBet v 1 and rBet v 1. Different IFN-gamma/IL-5 ratios were found, but were not affected by the different stimulants. Five nPhl p 5 T-cell lines responded equally well to natural and recombinant and even to extensively substituted rPhl p 5 proteins, except for one mutant, which did not react in one line. Four nDer p 1 T-cell lines varied in stimulation to nDer p 1, rDer p 1 and mutated rDer p 1 allergens. One line did not respond to some mutant rDer p 1. nPhl p 5 and nDer p 1 lines produced Th2 cytokines to all allergen preparations. Conclusions T-cell lines responding to natural purified allergens were also stimulated by recombinant allergens. These data suggests that for T-cell stimulation, one carefully selected isoform of the natural purified allergen can in most allergen systems substitute for the mixture of isoforms.