AIM To evaluate a system for bile acid formation in human hepatocytes in comparison with HepG2 cells.METHODS Hepatocytes were isolated from normal human liver tissue and were cultured in serum-freeWilliam's E medium. The medium was collected and renewed every 24 h. Bile acids and their precursors inmedia were finally analysed by gas chromatography-mass spectrometry.RESULTS Cholic acid (CA) and chenodeoxycholic acid (CDCA) conjugated with glycine or taurineaccounted for 70% and 25% of total steroids. One third of CDCA was also conjugated with sulphuric acid.Dexamethasone and thyroid hormone alone or in combination did not significantly affect bile acid formation.The addition of cyclosporin A (10 tm) inhibited the synthesis of CA and CDCA by about 13% and 30%,respectively.CONCLUSION Isolated human hepatocytes in primary culture behave as in the intact liver by convertingalmost quantitatively cholesterol to conjugated CA and CDCA. This is in contrast to cultured HepG2 cells,which release large amounts of bile acid precursors and unconjugated bile acids into the medium.

Ain. To study the effect of kanglemycin C (KC) on production and gene transcription of lymphokins. Methods. Cell proliferation and lymphokin activities were quantified with MTT colorimetry and ELISA, and genetranscripdons of lymphokins semi-quantified with RT-PCR. Restlts. Suppression of KC on proliferation of enriched T-and B-cell respectively mediated by Con A and LPS was declined by addition of exogenous IL-1, IL-2, and IL-6. KC 80 nmol/L markedly inhibited IL-2 and IL-6 pro-duction and mRNA transcription of incubated mouse splenocytes induced by Con A. Additionally, KC had some sup-pression on IL-1β and IL-6 productions of peritoneal macrophage stimulated by LPS (5 μg/mL), whereas cyclosporine(CS) had not. Condusion. Immunosuppression of KC came true partially through the decrease of IL-1β, -2 and -6 productions,especially of IL-2. However, CS's immunosuppression was mainly through the decrease of IL-2 procduction.

Objective　To test the immunosuppressive effect of cyclosporine (Cs) in a polymer placed in the anterior chamber of corneal allograft recipients. Methods　Wistar inbred rats with vascularized corneas were recipients of corneal allografts from Sprague-Dawley donor rats. Rats underwent penetrating keratoplasty and were divided randomly into four groups: untreated control animals (UCA); Cs-polymer anterior chamber recipients (CPA); co-polymer subconjunctival recipients (CPS); and Cs-olive oil drop recipients (COO). Grafts were examined by slit lamp every 3 days and clinical conditions were scored. Cs concentration in the aqueous humor was assayed at 1, 2, and 4 weeks. At 1, 2 and 4 weeks after transplantation, the operated eyes were collected for histopathological evaluation of the grafts.Results　The median survival time of the allografts was 8.2±1.48 days for the UCA group, 11.4±2.50 days for the CPS group, and 17.0±2.00 days for the CPA group. There was a statistically significant difference (P<0.05) between survival time of the allografts in the animals of the CPA group compared to the other groups of graft recipients. Significantly higher concentrations of Cs were found in the eyes given an anterior chamber implant of Cs-polymer, compared to other treatment groups or untreated rats. A transient inflammatory response in the anterior chamber was observed in the CPA group. Conclusions　Cs-polymer placed in the anterior chamber significantly prolongs corneal allograft survival time in a high risk corneal graft rejection model. This intraocular delivery system may be a valuable adjunct for the suppression of immune graft rejection.