title: High-level expression, purification and production of the fungal immunomodulatory protein-gts in baculovirus-infected insect larva.
abstract: Fip-gts, a fungal immunomodulatory protein (Fip) isolated from Ganoderma tsugae (gts), has been reported to possess therapeutic effects in the treatment of cancer and autoimmune disease. To cost-effectively produce Fip-gts and bypass the bottleneck involved in its time-consuming purification from G. tsugae, in this study, we incorporated the SP(bbx) secretion signal into recombinant baculovirus for expressing glycosylated and bioactive rFip-gts in baculovirus-infected insect cells and Trichoplusia ni larva. This is the first study to employ the aerosol infecting T. ni larva with recombinant baculovirus for economical and high-level production of foreign proteins. In this study, one purification could yield 10 mg of rFip-gts protein merely from ∼100 infected T. ni larvae by aerosol inoculation, corresponding to 5 L (5 × 10⁹ cells) of the infected Sf21 culture. In addition, the rFip-gts purified from T. ni larvae could induce the expression of interleukin-2 in murine splenocytes with an immunoresponsive level similar to that induced by LZ-8 (a known potent immunomodulatory protein purified from Ling zhi, Ganoderma lucidum). Thus, our results demonstrated that the larva-based baculovirus expression system can successfully express rFip-gts with the assembling capability required for maintaining immunomodulatory and anticancer activity. Our approach will open a new avenue for the production of rFip-gts and facilitate the immunoregulatory activity of rFip-gts available in the future.
authors.affiliation: Department of Science Technology, Chung Yuan Christian University, Chung Li, Taiwan 32023, Republic of China.
authors.forename: Tzong-Yuan
authors.initials: TY
authors.lastname: Wu
authors.forename: Hsin-An
authors.initials: HA
authors.lastname: Chen
authors.forename: Feng-Yin
authors.initials: FY
authors.lastname: Li
authors.forename: Ching-Ting
authors.initials: CT
authors.lastname: Lin
authors.forename: Chi-Ming
authors.initials: CM
authors.lastname: Wu
authors.forename: Feng-Chia
authors.initials: FC
authors.lastname: Hsieh
authors.forename: Jason Tze-Cheng
authors.initials: JT
authors.lastname: Tzen
authors.forename: Sheng-Kuo
authors.initials: SK
authors.lastname: Hsieh
authors.forename: Jiunn-Liang
authors.initials: JL
authors.lastname: Ko
authors.forename: Tzyy-Rong
authors.initials: TR
authors.lastname: Jinn
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000472:pathogenicity*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D007313:Insecta / Q000821:virology*; D007814:Larva / Q000821:virology*
chemical_list: D005656:Fungal Proteins