Original article evidence of a novel allergenic protein Narcin in the bulbs of Narcissus tazetta

Several plant-derived allergens have been identifed which result in the formation of immunoglobulin E antibodies. Primarily, these allergens belong to the protein families including seed storage proteins, structural proteins and pathogenesis-related proteins. Several allergens are also reported from fower bulbs which cause contact dermatitis. Such symptoms are highly common with the bulb growers handling different species of Narcissus. Narcissus toxicity is also reported if the bulbs are consumed accidentally. The present study aimed to characterize the protein from the bulbs of Narcissus tazetta responsible for its allergenic response. A 13 kDa novel allergenic protein, Narcin was isolated from the bulbs of Narcissus tazetta. The protein was extracted using ammonium sulfate fractionation. The protein was further purifed by anion exchange chromatography followed by gel fltration chroma-tography. The N-terminal sequence of the frst 15 amino-acid residues was determined using Edman degradation. The allergenicity of the protein was measured by cytokine production using fow cytometry in peripheral blood mono-nuclear cells. Further estimation of total IgE was performed by ELISA method. This novel protein was found to induce pro-infammatory cytokines and thus induce allergy by elevating total IgE level. The novel protein, Narcin isolated from Narcissus tazetta was found to exhibit allergenic properties.