Immune focusing to major allergens prevents the recognition of minor antigens and allergy formation

摘要

Natural allergens are complex mixtures of multiple proteins,polysaccharides,and glycoproteins.They do not replicate inside the body and thus the concentration of individual proteins contacting immune system is very low.On the contrary,pathogens arc able to replicate after invasion by this mean increasing significantly the local concentration of antigens originated from these pathogens.Antigen presenting cells(APC)process foreign antigens originated from extracellular pathogens as well as from allergens through endosomai compartment where antigenic peptides are loaded on MHC class 11 molecules.The number of MHC complexes carrying the antigenic peptides on the surface of APC is proportional to the antigen concentration in endosomes.The selection of T cells recognizing different proteins from pathogens results both from the competition for MHC-peptide complexes and the number of APC-T cell contacts.Thus,immune response to pathogens is focused to dominant antigens whose peptides presented in excess,while allergic response is probably not focused due to the low concentration of allergen proteins in APC.The aim of this work was i)to estimate the number of proteins recognized during immunization with polycomponent allergen extract and ii)whether it is possible to focus allergic response to a single major allergen