Immunobiological characteristic of grass pollen allergens / Монголын Анагаах Ухаан

ABSTRACT

Grass pollens are one of the most important airborne allergen sources worldwide. The Poaceaefamily comprises about 9000 species, 20 species from five subfamilies are considered to be the mostfrequent causes of grass pollen allergy, and the allergenic relationships among them closely follow theirphylogenetic relationships. The allergic immune response to pollen of several grass species has beenstudied extensively over more than three decades. Eleven groups of allergens have been identified anddescribed, in most cases from more than one species. The most complete set of allergens has so farbeen isolated and cloned from Phleum pratense (timothy grass) pollen. Based on the prevalence of IgEantibody recognition among grass pollen-sensitized individuals, several allergens qualify as major, butmembers of two groups, groups 1 and 5, have been shown to dominate the immune response to grasspollen extract. Isoform variation has been detected in members of several of the allergen groups, whichin some cases can be linked to observed genetic differences. N-linked glycosylation occurs in membersof at least three groups. Carbohydrate- reactive IgE antibodies have been attributed to grass pollensensitization and found to cross-react with glycan structures from other allergen sources, particularlyvegetable foods. Another cause of extensive cross-reactivity are the group 12 allergens (profilins), whichbelong to a family of proteins highly conserved throughout the plant kingdom and present in all tissues.Members of eight allergen groups have been cloned and expressed as recombinant proteins capableof specific IgE binding. This development now allows diagnostic dissection of the immune response tograss pollen with potential benefits for specific immunotherapy.