Diagnosis of Grass Pollen Allergy with Recombinant Timothy Grass <i>(Phleum pratense)</i> Pollen Allergens

Abstract

In order to establish a test system for grass pollen allergy based on the use of recombinant allergens we chose timothy grass (Phleum pratense), a widely spread grass, as a model. From a lambda gtll cDNA expression library that we had constructed from pollen RNA of timothy grass (P. pratense), we had obtained with serum IgE from a grass pollen-allergic individual 60 IgE-binding clones. By differential testing with sera from different grass pollen-allergic patients, we selected three distinct clones encoding Phl p I (group I), Phl p V (group V) and profilin from timothy grass, which when used together allowed the diagnosis of grass pollen allergy in 97 out of 98 tested grass pollen-allergic patients employing a simple plaque lift technique. This recombinant test based on plaque lifts containing allergen-β-galactosidase fusion proteins was compared with IgE immunoblots using crude pollen protein extracts from timothy grass. Both methods were in good agreement with RAST scores and clinical data, and proofed to be useful for the diagnosis of grass pollen allergy. Our results further indicate that a limited panel of only two recombinant grass pollen allergens, Phl p I and Phl p V, together with the plant panallergen profilin could be sufficient for the diagnosis and possibly immunotherapy of grass pollen allergy.

Conversion of the major birch pollen allergen, Bet v 1, into two nonanaphylactic T cell epitope-containing fragments: candidates for a novel form of specific immunotherapy.

“…Sera from birch pollen allergic patients and control individuals were characterized by RAST and testing with recombinant allergens as described (13,20). In addition, all patients were characterized by case history and skin prick test.…”

The immunoglobulin-like modules Cε3 and α2 are the minimal units necessary for human IgE-FcεRI interaction

“…The Sf9 cell line was purchased from the German Collection of Microorganisms and Cell Cultures (Braunschweig, Germany). Sera were collected from allergic patients who were diagnosed on the basis of a case history indicative of type I allergy, skin prick testing, and the demonstration of allergen-specific serum IgE antibodies by radioallergosorbent test (RAST; Pharmacia & Upjohn Diagnostics, Uppsala, Sweden) (12). The human IgE-secreting myeloma cell line U266 was obtained from American Type Culture Collection (Rockville, Maryland, USA) (13).…”

A Human Monoclonal IgE Antibody Defines a Highly Allergenic Fragment of the Major Timothy Grass Pollen Allergen, Phl p 5: Molecular, Immunological, and Structural Characterization of the Epitope-Containing Domain

“…Sera were collected from grass pollen-allergic patients who were characterized by case history, skin prick testing, 125 I-labeled anti-human IgE Abs (RAST), and by testing with recombinant grass pollen allergens as described (31,32). Sera from allergic patients without grass pollen allergy and from nonallergic individuals were included as negative controls.…”