title: Cloning, expression, characterization, and computational approach for cross-reactivity prediction of manganese superoxide dismutase allergen from pistachio nut.
abstract: BACKGROUND
  Tree nut allergy is one of the common potentially life-threatening food allergies in children and adults. Recombinant food allergens offer new perspectives to solve problems of clinical and molecular allergology in diagnosis, research, and therapy of food allergies. So far, superoxide dismutase (s) has been identified as a panallergen and studied in different allergenic sources. Manganese Superoxide Dismutase (MnSOD) has also been reported in pistachio that may cause allergic reactions in atopic subjects. The aim of this study was to describe the cloning, expression, and purification of MnSOD from pistachio nut.
  
  
  METHODS
  The pistachio MnSOD was cloned and expressed in E. coli BL21 (DE3) using a vector pET-32b (+). A recombinant protein was purified by metal precipitation. The protein immunoreactivity was evaluated using patients' IgE binding by means of ELISA and immunoblotting assays.
  
  
  RESULTS
  The MnSOD gene from pistachio was successfully cloned and expressed in E. coli. The purified pistachio MnSOD was recognized by IgE in 10 (40%) out of the 25 sera tested. Our results also showed that this protein might trigger some cross-reactions toward IgE antibodies and thus could be considered as a panallergen.
  
  
  CONCLUSIONS
  For the first time recombinant manganese superoxide dismutase from nut source was expressed as a possible allergen. This pistachio allergen could be a possible basis for cross-reactivity with MnSOD from other sources.
authors.affiliation: Department of Food Science and Technology, Ferdowsi University of Mashhad, Mashhad, Iran; Immunology Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Reihaneh
authors.initials: R
authors.lastname: Noorbakhsh
authors.affiliation: Department of Food Science and Technology, Ferdowsi University of Mashhad, Mashhad, Iran.
authors.forename: Seyed Ali
authors.initials: SA
authors.lastname: Mortazavi
authors.affiliation: Immunology Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Sankian
authors.affiliation: Department of Food Science and Technology, Ferdowsi University of Mashhad, Mashhad, Iran.
authors.forename: Fakhri
authors.initials: F
authors.lastname: Shahidi
authors.affiliation: Immunology Department, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Assarehzadegan
authors.affiliation: Immunology Research Center, Bu-Ali Research Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Varastegan Institute for Medical Sciences, Mashhad, Iran. Electronic address: varasteha@mums.ac.ir.
authors.forename: AbdolReza
authors.initials: A
authors.lastname: Varasteh
mesh_terms: D000293:Adolescent; D000328:Adult; D000485:Allergens / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D002648:Child; D019295:Computational Biology; D003429:Cross Reactions; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D021184:Nut Hypersensitivity / Q000175:diagnosis / Q000276:immunology* / Q000628:therapy; D027927:Pistacia / Q000009:adverse effects; D014674:Plant Proteins, Dietary / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D011487:Protein Conformation; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D013482:Superoxide Dismutase / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D055815:Young Adult
chemical_list: D000485:Allergens; D014674:Plant Proteins, Dietary; D011994:Recombinant Proteins; D007073:Immunoglobulin E; D013482:Superoxide Dismutase