Phleum pratense pollen allergens (Phl p allergens)

Phleum pratense pollen allergens, commonly known as Timothy grass pollen allergens, are a group of proteins primarily from groups 1-13 (e.g., Phl p 1 as beta-expansin, Phl p 5 as 32 kDa protein, Phl p 6 as 11 kDa group VI allergen) that elicit IgE-mediated immune responses in sensitized individuals. These allergens are major contributors to seasonal allergic rhinitis, asthma, and conjunctivitis in grass pollen-allergic patients, with Phl p 1 and Phl p 5 recognized by over 90% and 65% of patients, respectively, serving as markers of genuine sensitization. They trigger histamine release and inflammation upon inhalation, with isoforms showing structural variability (e.g., Phl p 5a at 38 kDa and Phl p 5b at 32 kDa) that influence epitope recognition and individual reactivity patterns. While not traditional therapeutic targets like receptors or enzymes, they are central to allergen immunotherapy (AIT), where recombinant forms or extracts desensitize patients by modulating IgE responses. Safety challenges include risk of systemic reactions during treatment, particularly in polysensitized individuals.

Other names

Timothy grass pollen allergensPhl p 1Phl p 2Phl p 3Phl p 4Phl p 5Phl p 6Phl p 7Phl p 11Phl p 12Phl p 13