Parietaria judaica pollen allergens (Par j allergens)

Parietaria judaica pollen allergens are a group of clinically significant proteins derived from the pollen of the Pellitory-of-the-wall plant, a dominant source of aeroallergens in Mediterranean and coastal regions (D'Amato et al., 2007). The most potent allergens within this group are Par j 1 and Par j 2, which belong to the non-specific lipid transfer protein (nsLTP) family and exhibit high thermal and proteolytic stability (UniProt P43214, P55958). Biologically, these proteins are involved in plant defense and lipid transport, but upon inhalation by sensitized individuals, they cross-link allergen-specific IgE on the surface of mast cells and basophils. This triggers the release of inflammatory mediators, leading to allergic rhinitis, conjunctivitis, and bronchial asthma (World Allergy Organization). In clinical practice, these allergens serve as the primary components of allergen-specific immunotherapy (AIT) formulations, which aim to modify the underlying disease by inducing immunological tolerance (Akdis & Akdis, 2014). The therapeutic mechanism involves the induction of regulatory T cells (Tregs) and the production of blocking IgG4 antibodies that prevent IgE-mediated activation.

Other names

Pellitory-of-the-wall pollen allergensPar j 1Par j 2Par j 3Par j 4Parietaria judaica extract

Allergen-specific immunotherapy (AIT) induces peripheral T-cell tolerance, promotes the expansion of regulatory T cells (Tregs), and stimulates the production of allergen-specific IgG4 antibodies that compete with IgE for allergen binding, thereby inhibiting mast cell degranulation (Akdis & Akdis, 2014).