Polcalcin Phl p 7 (Phl p 7)

Polcalcin Phl p 7 is a highly cross-reactive calcium-binding protein found in the pollen of Phleum pratense (Timothy grass). Structurally, it is an EF-hand protein that functions as a pan-allergen, meaning it shares high sequence homology with polcalcins from many other flowering plants. Although it is classified as a minor allergen, sensitization to Phl p 7 is a clinical marker for poly-sensitization and can lead to severe respiratory symptoms such as allergic rhinitis and asthma. In a therapeutic context, Phl p 7 is a target for allergen-specific immunotherapy (AIT), where standardized or recombinant versions of the protein are used to induce immunological tolerance in sensitized patients. Modern drug development efforts involve the creation of hypoallergenic variants that reduce IgE-mediated side effects while maintaining the ability to stimulate regulatory immune responses. It also serves as an essential diagnostic tool for identifying cross-reactivity patterns in patients with complex pollen allergies.

Other names

Calcium-binding pollen allergen Phl p 7Timothy grass pollen polcalcinP7Phl p 7.0101

Induction of immune tolerance through allergen-specific immunotherapy (AIT), which involves shifting the immune response from a Th2 to a Th1/Treg profile, leading to the production of blocking IgG4 antibodies and the desensitization of mast cells and basophils.