Jun o 1, a Cross-reactive Juniperus oxycedrus Allergen With Unique Structural and Immunogenic Properties

Area of Science:

• Allergen characterization
• Immunology
• Plant biochemistry

Background:

• Juniperus oxycedrus (Cupressaceae family) is common in the Mediterranean.
• The allergenic potential of J. oxycedrus pollen remains largely uninvestigated.

Purpose of the Study:

• To characterize Jun o 1, a J. oxycedrus allergen.
• To compare Jun o 1 with Cup a 1, a known cypress allergen.

Main Methods:

• Purification of native and recombinant Jun o 1 (rJun o 1) and Cup a 1.
• Characterization using SDS-PAGE, 2D-electrophoresis, Western blot, and mass spectrometry.
• Evaluation of IgE binding, cross-reactivity, and mast cell activation using patient sera and mouse models.

Main Results:

• Jun o 1 exists as multiple isoforms and forms oligomers, unlike Cup a 1.
• IgE binding to Jun o 1 is influenced by both protein and carbohydrate components.
• Jun o 1 showed greater IgE-binding inhibition compared to Cup a 1 in allergic patients from J. oxycedrus regions.

Conclusions:

• Jun o 1 is a relevant major allergen in cypress allergy.
• Structural similarities with Cup a 1 cause cross-reactivity.
• Unique protein-glycan determinants contribute to Jun o 1's specific allergenic properties.