Alergenost enzimski procesovanih nutritivnih alergena

Abstract

U cilju poboljšanja funkcionalnih karakteristika hrane sve se češće upotrebljavaju enzimi. Prilikom modifikacije proteina hrane enzimima u cilju dobijanja poboljšanih svojstava neophodno je obratiti pažnju na moguće promene u alergenosti novonastalih modifikata. U ovoj tezi ispitan je uticaj umrežavanja alergena kikirikija i mleka na njihovu alergenost. Pokazano je da se tretmanima proteina kikirikija oksidativnim enzimima ne pojačava in vitro IgE reaktivnost alergena, niti ex vivo aktivacija bazofila. Umrežavanje kazeina, kao glavnog alergena mleka, pokazalo je neznatno izmenjeno vezivanje IgE antitela, bez narušavanja funkcionalnog odgovora u smislu aktivacije bazofila. Rezultati dobijeni u in vitro studijama, kada je reč o potencijalnoj primeni enzima u komercijalne svrhe, uzimaju se sa rezervom, s obzirom na složenost mehanizama alergijske senzitizacije i opasnosti koje uvođenje izmenjenih alergena može da prouzrokuje. Ispitivanja na životinjskim modelima alergija na hranu predstavljaju pouzdaniji pokazatelj efekata koje bi modifikovani alergeni mogli da prouzrokuju. U slučaju proteina kikirikija umreženih tirozinazama, u mišjem modelu alergije na kikiriki, nije došlo do pojačanja alergijske senzitizacije i proteini su sačuvali sposobnost indukcije oralne tolerancije. Umrežavanje proteina kikirikija lakazom smanjuje alergijsku senzitizaciju, izaziva jači tolerogeni odgovor i potencijalno bi mogao da se koristi i za imunoterapiju alergija na kikiriki...

Enzymes are increasingly exploited for improving functional characteristics of food. During the enzymatic modification of food, it is necessary to pay attention to a possible change in allergenicity of obtained novel modificates. The influence of crosslinking of peanut and milk allergens on their allergenicity has been investigated in this thesis. It has been shown that treatment of peanut proteins by oxidative enzymes does not enhance the in vitro IgE reactivity of these allergens, nor ex vivo activation of basophils. Crosslinking of casein, which is a major milk allergen, slightly altered binding of IgE antibodies, without disturbing the functional response in terms of the activation of basophils. Results of in vitro studies regarding the potential application of enzymes for commercial purposes are not taken for granted, due to the complexity of the mechanisms of allergic sensitization and the risk that the modified allergen may introduce. Results obtained from studies of animal models of food allergy more reliably reflect the effects caused by modified allergens. There was no increase in allergic senzitization with peanut proteins crosslinked by action of tyrosinases in a mouse model of peanut allergy, and, also, induction of oral tolerance was preserved. Crosslinking of peanut proteins by laccase reduced allergic sensitization, mounted more pronounced tolerogenic response and potentially could be used for immunotherapy of allergy to peanuts...