Monoclonal Antibody-Based 2-Site ELISA for Profilin Measurement in Korean Melon and Other Melon Cultivars

Introduction: Pollen-food allergy syndrome (PFAS) is commonly associated with profilin, a highly cross-reactive pan-allergen found in a variety of plants, including fruits, vegetables, and pollens. In Korea, the Korean melon (Cucumis melo var. makuwa), commonly known as Chamoe, has been identified as a major trigger for PFAS. However, the lack of standardized allergen extracts limits the consistency and reliability of diagnosis and therapeutic efficacy. This study aimed to develop a novel two-site ELISA for quantifying Cuc m 2, the major profilin allergen from Korean melon, to support the standardization of allergen extracts. Methods: Recombinant Cuc m 2.0301 was used to immunize mice and generate hybridomas that produce monoclonal antibodies recognizing both Cuc m 2.0102 and Cuc m 2.0301 isoallergens. Results: The ELISA system demonstrated high sensitivity, with detection limits as low as 10 μg/mL for melon extracts and 3 ng/mL for recombinant Cuc m 2. We quantified Cuc m 2 concentrations in various melon cultivars, with values ranging from 5.43 to 78.25 ng/mL. Cross-reactivity was observed with tomato profilin (Sola l 1), but not with profilins from pineapple, banana, or timothy grass pollen. The allergenic potency of melon extracts was generally correlated with Cuc m 2 concentration, except for Korean melon, suggesting the presence of additional allergenic components. Conclusion: This study provides a reliable method for quantifying Cuc m 2, which may support the standardization and consistency of allergy diagnostic materials and allergen surveillance.