Purification and characterization of Parthenium hysterophorus flower proteins that exhibit inherent immunological responses

Abstract

Introduction: To insight the importance of immunoglobulin’s (Ig) role in allergic reactions and to determine the mechanism of IgG in allergic responses. Aim: This study aimed at purifying the proteins from Parthenium hysterophorus flower and to check their allergic activity with IgG. Materials and Methods: Purification methods of phenol extraction for P. hysterophorus flower proteins and affinity chromatography for IgG purification were used. The purified allergens were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional (2D)-electrophoresis, mass spectrometry, immunoblot, and IgE-ELISA. Results: SDS-PAGE analysis of pollens under reduced conditions revealed four proteins with molecular weights 44 kDa, 38 kDa, 18 kDa, and 23 kDa as the major allergens of Parthenium pollen with an isoelectric point of 10 by 2D-PAGE. Furthermore, cross-reactivity between allergens was investigated by IgG-ELISA, which was identified at 100 ng/ml concentration of IgG antibody. The result of Fourier transform infrared spectroscopy analysis confirmed the presence of alcohol and amides, whereas the mass spectra were matched by the National Center for Biotechnology Information/Blastp to find possible glycopeptides applying settings of GlycoMod search program. Conclusion: The research findings suggest that several proteins in the range of 18-40 kDa could be used as diagnostic markers for patients allergic to P. hysterophorus.