title: Production of Active Nonglycosylated Recombinant B-Chain of Type-2 Ribosome-Inactivating Protein from Viscum articulatum and Its Biological Effects on Peripheral Blood Mononuclear Cells.
abstract: Type-2 ribosome-inactivating proteins, composed of a toxic A-chain and lectin-like B-chain, display various biological functions, including cytotoxicity and immunomodulation. We here cloned the lectin-like B-chain encoding fragment of a newly identified type-2 RIP gene, articulatin gene, from Viscum articulatum, into a bacterial expression vector to obtain nonglycosylated recombinant protein expressed in inclusion bodies. After purification and protein refolding, soluble refolded recombinant articulatin B-chain (rATB) showed lectin activity specific toward galactoside moiety and was stably maintained while stored in low ionic strength solution. Despite lacking glycosylation, rATB actively bound leukocytes with preferential binding to monocytes and in vitro stimulated PBMCs to release cytokines without obvious cytotoxicity. These results implicated such a B-chain fragment as a potential immunomodulator.
authors.affiliation: Institute of Biochemical Sciences, National Taiwan University, Taipei 106, Taiwan.
authors.forename: Tzu-Li
authors.initials: TL
authors.lastname: Lu
authors.forename: Jing-Yuan
authors.initials: JY
authors.lastname: Chuang
authors.forename: Jai-Sing
authors.initials: JS
authors.lastname: Yang
authors.forename: Shau-Ting
authors.initials: ST
authors.lastname: Chiu
authors.forename: Nai-Wan
authors.initials: NW
authors.lastname: Hsiao
authors.forename: Mei-Chen
authors.initials: MC
authors.lastname: Wu
authors.forename: Shih-Hsiung
authors.initials: SH
authors.lastname: Wu
authors.forename: Ching-Hsiang
authors.initials: CH
authors.lastname: Hsu