Triptolide inhibits proinflammatory factor-induced over-expression of class II MHC and B7 molecules in renal tubular epithelial cells.
OBJECTIVE
To investigate the effects of triptolide on proinflammatory factor-induced over-expression of class II major histocompatibility complex (class II MHC), B7-1, B7-2, and intercellular adhesion molecule-1 (ICAM-1) in human proximal tubular epithelial (HKC) cells.


METHODS
HKC cells were exposed to both interferon gamma (IFN-gamma, 200 microg/L) and tumor necrosis factor alpha (TNF-alpha, 20 microg/L) and cultured in media containing different concentrations of triptolide for 24 h. Class II MHC, B7-1, B7-2, and ICAM-1 levels in HKC cells were evaluated by flow cytometry. ICAM-1 mRNA level was measured by semi-quantitative RT-PCR method.


RESULTS
HKC cells expressed quite high level of ICAM-1 and very low levels of class II MHC, B7-1, and B7-2 molecules. Class II MHC, B7-1, B7-2, and ICAM-1 levels in HKC cells were significantly increased by the costimulation of IFN-gamma and TNF-alpha. Triptolide inhibited the over-expression of class II MHC, B7-1, and B7-2 molecules in a concentration-dependent manner. The up-regulations of ICAM-1 molecules and ICAM-1 mRNA level were not altered by triptolide.


CONCLUSIONS
Triptolide can significantly inhibit proinflammatory factors induced over-expression of class II MHC, B7-1, and B7-2 costimulatory factors in tubular epithelial cells. These results may contribute to the therapeutic effects of triptolide in some renal diseases.
Li
Heng
H
Research Institute of Nephrology, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China. zhihong@public1.ptt.js.cn
Liu
Zhi-Hong
ZH
Dai
Chun-Sun
CS
Liu
Dong
D
Li
Lei-Shi
LS
D015703:Antigens, CD / Q000096:biosynthesis* / Q000235:genetics; D018122:B7-1 Antigen / Q000096:biosynthesis* / Q000235:genetics; D051940:B7-2 Antigen; D002478:Cells, Cultured; D004224:Diterpenes / Q000494:pharmacology*; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D004852:Epoxy Compounds; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics; D007687:Kidney Tubules, Proximal / Q000166:cytology*; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000235:genetics; D010616:Phenanthrenes
D015703:Antigens, CD; D018122:B7-1 Antigen; D051940:B7-2 Antigen; C497964:CD86 protein, human; D004224:Diterpenes; D004852:Epoxy Compounds; D000949:Histocompatibility Antigens Class II; D007166:Immunosuppressive Agents; D008562:Membrane Glycoproteins; D010616:Phenanthrenes; D018799:Intercellular Adhesion Molecule-1; C001899:triptolide