Heterogeneity of commercial timothy grass pollen extracts
Article first published online: 28 JUN 2008
© 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Ltd
Clinical & Experimental Allergy
Volume 38, Issue 8, pages 1400–1408, August 2008
How to Cite
Focke, M., Marth, K., Flicker, S. and Valenta, R. (2008), Heterogeneity of commercial timothy grass pollen extracts. Clinical & Experimental Allergy, 38: 1400–1408. doi: 10.1111/j.1365-2222.2008.03031.x
- Issue published online: 18 JUL 2008
- Article first published online: 28 JUN 2008
- Submitted 19 June 2007; revised 7 January 2008; accepted 15 April 2008
- allergen measurement;
- grass pollen allergy;
- recombinant allergen;
- skin prick test
Background The diagnosis and specific immunotherapy of allergy is currently performed with allergen extracts prepared from natural allergen sources.
Objective To analyse commercial timothy grass pollen allergen extracts used for in vivo diagnosis regarding their qualitative and quantitative allergen composition and in vivo biological activity.
Methods Antibodies specific for eight timothy grass pollen allergens (Phl p 1, Phl p 2, Phl p 4, Phl p 5, Phl p 6, Phl p 7, Phl p 12, Phl p 13) were used to detect these allergens in timothy grass pollen extracts from four manufacturers by immunoblotting. ELISA assays were developed and used to quantify the three major allergens (Phl p 1, Phl p 2, Phl p 5) in the extracts. The magnitude of skin responses to the four extracts was studied by skin prick testing in 10 grass pollen-allergic patients.
Results The allergen extracts showed broad variations in protein compositions and amounts (24.1–197.7 μg/mL extract). Several allergens could not be detected in certain extracts or appeared degraded. A considerable variability regarding the contents of major allergens was found (Phl p 1: 32–384 ng/mL; Phl p 2: 1128–6530 ng/mL, Phl p 5: 40–793 ng/mL). Heterogeneous skin test results were obtained with the extracts in grass pollen-allergic patients.
Conclusions Timothy grass pollen extracts from different manufacturers exhibit a considerable heterogeneity regarding the presence of individual allergens and hence yield varying in vivo test results. Problems related to the use of natural grass pollen allergen extracts may be circumvented by using defined recombinant grass pollen allergens.