· AIM: To investigate the role of intercellular adhesion molecule-1 (ICAM-1) in the graft rejection of rabbit penetrating keratoplasty (PKP).· METHODS: Sutures were used to produce corneal neovascularization (CNV) on New Zealand white rabbits to make PKP model. Graft mean survival time and rejection index were determined. The levels of sICAM-1 in serum and aqueous humor were dynamically determined by enzyme-linked immunosorbent assay (ELISA).Immunohistochemical technique was used on cornea to get the evidence of expression and distribution of ICAM-1.· RESULTS: Graft mean survival time is (12.4±1.3) days.The mean sICAM-1 levels in aqueous humor and serum in the control animals that did not undergo surgery were (16.6±3.6)ng/L and (95.2±6.3) ng/L respectively. Levels in aqueous humor and serum for the graft rejection group increased postoperatively, continued to increase to (53.9±19.2)ng/Land (378.8±30.6)ng/L, compared to those in the other group (P ＜0.01). ICAM-1 positive cells were found in the graft rejection group.· CONCLUSION: ICAM-1 plays a critical role in initiating and maintaining corneal graft rejection. Sequential determination of serum sICAM-1 after operation may be of value in the prediction and diagnosis of acute rejection.

OBJECTIVETo investigate the effect of hepatitis B virus(HBV) X gene on the expression of SPG21.

METHODSThe expressions of SPG21 mRNA and protein in HepG2 and HepG2.2.15 cells were tested by RT-PCR and western blot. HepG2 cells were co-transfected with reporter plasmid pGL3-SPG21 and plasmids carrying individual genes of HBV, the luciferase activity was measured and the expressions of SPG21 were detected by RT-PCR and western blot.

RESULTSThe expressions of SPG21 mRNA and protein were higher in HepG2.2.15 cells than in HepG2 cells (0.36+/-0.06 vs 0.21+/-0.05, P value is less than 0.05). The activity of SPG21 in HepG2 cells transfected with pCMV-X was higher (875+/-27 vs 67+/-12, P value is less than 0.01) as compared to blank control group (transfected with pCMV-tag2B). HBV X gene enhanced SPG21 gene promoter activity, SPG21 mRNA expression and SPG21 protein production in HepG2 cells in a dose-dependent manner.

CONCLUSIONHBV X gene can specially activate SPG21 expression.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; DNA, Viral ; genetics ; Hep G2 Cells ; Hepatitis B virus ; genetics ; Humans ; RNA, Messenger ; genetics ; Trans-Activators ; genetics ; Transfection