title: Significance of MD-2 and MD-2B expression in rat liver during acute cholangitis.
abstract: OBJECTIVE
  To investigate the expression of myeloid differentiation protein-2 (MD-2), MD-2B (a splicing isoform of MD-2 that can block Toll-like receptor 4 (TLR4)/MD-2 LPS-mediated signal transduction) and TLR4 in the liver of acute cholangitis rats.
  
  
  METHODS
  Male Sprague-Dawley rats (SPF level) were randomly divided into four groups: (A) sham-operated group; (B) simple common bile duct ligation group; (C) acute cholangitis group; and (D) acute cholangitis anti-TLR4 intervention group (n = 25 per group). Rat liver tissue samples were used to detect TLR4, MD-2 and MD-2B mRNA expression by fluorescence quantitative PCR in parallel with pathological changes.
  
  
  RESULTS
  In acute cholangitis, liver TLR4 and MD-2 mRNA expression levels at 6, 12, 24, 48 and 72 h were gradually up-regulated but MD-2B mRNA expression gradually down-regulated (P < 0.05). After TLR4 antibody treatment, TLR4 and MD-2 mRNA expression were lower compared with the acute cholangitis group (P < 0.05). However, MD-2B mRNA expression was higher than in the acute cholangitis group (P < 0.05). MD-2 and TLR4 mRNA expressions were positively correlated (r = 0.94981, P < 0.05) and MD-2B mRNA expression was negatively correlated with MD-2 and TLR4 mRNA (r = -0.89031, -0.88997, P < 0.05).
  
  
  CONCLUSIONS
  In acute cholangitis, MD-2 plays an important role in the process of TLR4- mediated inflammatory response to liver injury while MD-2B plays a negative regulatory role.
authors.affiliation: Hui-Lai Miao, Zhi-Dong Qiu, Ming-Yi Li, Ming Chen, Nian-Ping Chen, Department of Hepatobiliary Surgery, the Affiliated Hospital of Guangdong Medical College, Zhanjing 524001, Guangdong Province, China.
authors.forename: Hui-Lai
authors.initials: HL
authors.lastname: Miao
authors.forename: Zhi-Dong
authors.initials: ZD
authors.lastname: Qiu
authors.forename: Fu-Long
authors.initials: FL
authors.lastname: Hao
authors.forename: Yong-Hui
authors.initials: YH
authors.lastname: Bi
authors.forename: Ming-Yi
authors.initials: MY
authors.lastname: Li
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.forename: Nian-Ping
authors.initials: NP
authors.lastname: Chen
authors.forename: Fei
authors.initials: F
authors.lastname: Zhou