title: Activation of macrophages by polysaccharide-protein complex from Lycium barbarum L.
abstract: Macrophages play crucial roles in innate immunity. This paper reports that a polysaccharide-protein complex isolated from Lycium barbarum (LBP) is able to activate macrophages. LBP was isolated from Lycium barbarum fruit and separated to five homogenous fractions, designated LBPF1, LBPF2, LBPF3, LBPF4 and LBPF5. It was found that LBP (50 mg/kg, i.p.) markedly upregulated the expressions of CD40, CD80, CD86 and MHC class II molecules on peritoneal macrophages. In vitro studies showed that LBP and LBPF1-5 activated transcription factors NF-kappaB and AP-1 by RAW264.7 macrophage cells, induced TNF-alpha, IL-1beta, IL-12p40 mRNA expression, and enhanced TNF-alpha production in a dose-dependent manner. Furthermore, LBP (50 mg/kg, i.p.) significantly enhanced macrophage endocytic and phagocytic capacities in vivo. These results indicate that LBP enhances innate immunity by activating macrophages. The mechanism may be through activation of transcription factors NF-kappaB and AP-1 to induce TNF-alpha production and upregulation of MHC class II costimulatory molecules.
authors.affiliation: WHO Collaborating Centre for Research and Training in Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore.
authors.forename: Zhisong
authors.initials: Z
authors.lastname: Chen
authors.forename: Mei Yun
authors.initials: MY
authors.lastname: Soo
authors.forename: Nalini
authors.initials: N
authors.lastname: Srinivasan
authors.forename: Benny Kwong Huat
authors.initials: BK
authors.lastname: Tan
authors.forename: Soh Ha
authors.initials: SH
authors.lastname: Chan
mesh_terms: D000818:Animals; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D004705:Endocytosis / Q000187:drug effects; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D007113:Immunity, Innate; D053762:Interleukin-12 Subunit p40 / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D032305:Lycium / Q000737:chemistry*; D008262:Macrophage Activation / Q000187:drug effects*; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D016328:NF-kappa B / Q000378:metabolism; D010587:Phagocytosis / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D053762:Interleukin-12 Subunit p40; D053583:Interleukin-1beta; D016328:NF-kappa B; D010936:Plant Extracts; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha