CHARACTERIZATION OF ALLERGENS FROM TRISETUM-PANICEUM POLLEN - AN IMPORTANT AEROALLERGEN IN MEDITERRANEAN CONTINENTAL CLIMATIC AREAS

Background Trisetum paniceum is a grass plant which is characteristic of a Mediterranean continental climate and has been described as one o f the major causes of type I allergy in the Madrid region. Objectives To identify and characterize the allergens of Trisetum paniceum pollen , Methods Allergenic extracts were prepared by 24 h incubation of poll ens in a buffered solution. Proteins were analysed by a new two-dimens ional system in which agarose plates were used for isoelectric focusin g. Two-dimensionally resolved proteins were electrically transferred t o Immobilon membranes and the allergens immunochemically detected. Pro teins from six grass pollens were bound to a membrane and incubated wi th a pool of serum from grass-pollen-sensitized patients. The bound Ig E antibodies were then eluted and used to identify the proteins of Tri setum paniceum pollen that allergenically crossreact with allergens fr om other pollen grasses. Results Relative to total protein content, Tr isetum paniceum pollen had a high proportion of reactive proteins. On the basis of their molecular characteristics, allergens could be class ified as group 1, 2, 4 and 5 components yet included an atypical propo rtion of basic components. All identified allergens were crossreactive with allergens from the remaining grass pollens studied. Conclusions Trisetum paniceum pollen contains a high proportion of allergens and t hese include a group of basic proteins which an not detected in other phylogenetically related pollens and could be of allergological intere st.