Suppression of cytokine production and cell adhesion molecule expression in human monocytic cell line THP-1 by Tripterygium wilfordii polysaccharide moiety.
Extracts of the vine-like plant Tripterygium wilfordii (TW) have been widely used in China as an immunosuppressant and anti-inflammatory drug for the treatments of rheumatoid arthritis, lupus erythematosus and other inflammatory disorders. In this study the molecular mechanisms of action of three TW extracts (ethanol, aqueous, polysaccharide) on the expression of inflammatory cytokines and adhesion molecules were investigated by RT-PCR and immunofluorescence binding techniques. The lipopolysaccharide (LPS)-mediated stimulatory effects of tumor necrosis factor-alpha (TNF-alpha) cytokine production and cell adhesion molecule (CD11c, CD18, CD14, CD54) expression in human monocytic THP-1 cells were modulated by treatments of the TW extracts or tacrolimus (FK506). The TW polysaccharide moiety exhibited more profound immunosuppressive properties than the aqueous and ethanol extracts. Biochemical characterization of the polysaccharide moiety revealed a major molecular weight of 22 kDa (viz. PSP22). The PSP22 was found to be a potential immunosuppressant that manifests the necessary immunomodulating properties.
Luk
J M
JM
Department of Surgery, University of Hong Kong Medical Center, Queen Mary Hospital, Pokfulam. jmluk@hkucc.hku.hk
Lai
W
W
Tam
P
P
Koo
M W
MW
D018821:CD18 Antigens / Q000096:biosynthesis; D002460:Cell Line; D004365:Drugs, Chinese Herbal; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D016167:Integrin alphaXbeta2 / Q000096:biosynthesis; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis*; D018950:Lipopolysaccharide Receptors / Q000096:biosynthesis; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism*; D010936:Plant Extracts / Q000494:pharmacology; D011134:Polysaccharides / Q000494:pharmacology*; D029757:Tripterygium; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
D018821:CD18 Antigens; D004365:Drugs, Chinese Herbal; D007166:Immunosuppressive Agents; D016167:Integrin alphaXbeta2; D018950:Lipopolysaccharide Receptors; D010936:Plant Extracts; D011134:Polysaccharides; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1