BACKGROUND: Mountain cedar (Juniperus ashei) pollen commonly causes a winter time allergic rhinitis in the central USA. Jun a 1 is the dominant allergenic protein, but biologically active recombinant Jun a 1 has not been successfully expressed, despite numerous attempts with several expression systems. METHOD: Jun a 1 cDNA was inserted into a tobacco mosaic virus vector and transferred to Agrobacterium tumefaciens. Bacteria were syringe-inoculated into leaves of Nicotiana benthamiana (agroinoculation). The interstitial (apoplastic) fluid containing Jun a 1 was isolated. The recombinant protein was analyzed by SDS-PAGE, N-terminal sequencing and MALDI-TOF to confirm identity. Immunogenicity was examined with IgE from allergic patient's sera, mouse monoclonal anti-Jun a 1 antibodies, IgE-binding inhibition and by degranulation of RBL SX-38 cells sensitized with sera from allergic patients. Pectate lyase activity was assayed by capillary zone electrophoresis and mass spectrometry analysis. RESULTS: Recombinant Jun a 1 was recovered in good quantity (100 μg/g leaf material), was confirmed as Jun a 1, bound IgE from sera from cedar hypersensitive patients and inhibited IgE binding to native Jun a 1. Jun a 1 mutants were created and their pectate lyase activity quantified. For the first time, Jun a 1 pectate lyase activity was demonstrated, which may explain the necrosis seen on host plants, which was similar to that of control plants expressing banana pectate lyase. CONCLUSIONS: A means of producing recombinant Jun a 1 is now available for structure/function studies and potentially for diagnostic and therapeutic uses.
BACKGROUND: Mountain cedar (Juniperus ashei) pollen commonly causes a winter time allergic rhinitis in the central USA. Jun a 1 is the dominant allergenic protein, but biologically active recombinant Jun a 1 has not been successfully expressed, despite numerous attempts with several expression systems. METHOD: Jun a 1 cDNA was inserted into a tobacco mosaic virus vector and transferred to Agrobacterium tumefaciens. Bacteria were syringe-inoculated into leaves of Nicotiana benthamiana (agroinoculation). The interstitial (apoplastic) fluid containing Jun a 1 was isolated. The recombinant protein was analyzed by SDS-PAGE, N-terminal sequencing and MALDI-TOF to confirm identity. Immunogenicity was examined with IgE from allergicpatient's sera, mouse monoclonal anti-Jun a 1 antibodies, IgE-binding inhibition and by degranulation of RBL SX-38 cells sensitized with sera from allergicpatients. Pectate lyase activity was assayed by capillary zone electrophoresis and mass spectrometry analysis. RESULTS: Recombinant Jun a 1 was recovered in good quantity (100 μg/g leaf material), was confirmed as Jun a 1, bound IgE from sera from cedar hypersensitivepatients and inhibited IgE binding to native Jun a 1. Jun a 1 mutants were created and their pectate lyase activity quantified. For the first time, Jun a 1 pectate lyase activity was demonstrated, which may explain the necrosis seen on host plants, which was similar to that of control plants expressing banana pectate lyase. CONCLUSIONS: A means of producing recombinant Jun a 1 is now available for structure/function studies and potentially for diagnostic and therapeutic uses.
Authors: M Krebitz; U Wiedermann; D Essl; H Steinkellner; B Wagner; T H Turpen; C Ebner; O Scheiner; H Breiteneder Journal: FASEB J Date: 2000-07 Impact factor: 5.191
Authors: Randall M Goldblum; Bo Ning; Mark A Endsley; D Mark Estes; Barbara M Judy; Julius van Bavel; Terumi Midoro-Horiuti Journal: J Allergy Clin Immunol Date: 2014-06-27 Impact factor: 10.793