[Organogenesis of developing metanephroi allografted into nonimmunosuppressed adult rats].

OBJECTIVE: To explore novel methods of possible donor organ supply and immunologic tolerance induction of organ transplantation. METHODS: Whole metanephroi from d14-19 (E14-E19) embryos of pregnant rats were grouped and allografted into the omenta or near remnants of renal vessels of nonimmunosupressed adult rats. At the time of implantation, host rats underwent unilateral nephrectomy. Four weeks after implantation, allografted metanephroi in host rats were removed for gross, biochemical and histopathological examination. RESULT: Four weeks post-implantation, (1) E19 and E18 metanephroi had enlarged,but were replaced by connective tissues. (2) E17 and E16 metanephroi showed the signs of acute rejection such as hypercellular glomeruli and lymphocyte infiltration in peritubular spaces. E16 grafted metanephroi underwent mild acute rejection of Banff schema, while E17 had moderate or severe acute rejection. When Cyclosporine A was administrated, E17 metanephroi formed mature nephrons and collecting ducts with few lymphocyte infiltration. (3) Metanephroi from E15 and E14 embryos allografted into the omentum or near remnants of renal vessels of uninephrectomized adult rats were enlarged and vascularized, and formed mature tubules and glomeruli. (4) The concentrations of urea nitrogen and creatinine in cyst fluid of E15 and E16 metanephroi were increased 40-fold and 50-fold, which were comparable to those in bladder urine. (5) In contrast, rat metanephroi did not grow or differentiate in rats without host kidney resection. CONCLUSION: E14 and E15 metanephroi allografted into nonimmunosuppressed adult rats or E17 into cyclosporine-treated hosts undergo growth and differentiation and become vascularized. A variety of factors affect the growth and development of allografted metanephroi, while rejection is the main one.

[Effect of ciclosporin A on the organogenesis and function of embryonic metanephroi allografted into adult rats].

OBJECTIVE: To evaluate the effect of ciclosporin A (CsA) on the organogenesis and function of embryonic metanephroi allografted into adult rats. METHODS: The whole metanephroi from the 15, 16 and 17 embryonic day-old (E15, E16, E17) embryos of Sprague-Dawley (SD) rat were allografted into the omenta of SD adult rats with their left kidneys resected, which were divided into 2 categories: 3 CsA-treated groups of 10 rats (E15CsASD, E16CsASD, and E17CsASD) and 3 non-CsA-treated groups of 10 rats (E15SD, E16SD, and E17SD). Thirty SD rats without kidney resection were divided into 6 equal groups and underwent allografting embryonic metanephroi in the same manner as mentioned above. The E15 metanephroi of Lewis rats were allografted into the omenta of Thirty adult Brown Norway (BN) rats with one kidney resected. Were divided into 6 equal groups, received allografting of embryonic metanephroi, and injected with CsA of normal saline in the manner as mentioned above (E15CsABN and E15BN). Two to 4 weeks after implantation, the metanephroi allografted in host rats were removed for histopathological examination or anastomosed for renal function measurement 4 weeks later. RESULTS: (1) Four weeks after implantation, the E17SD and E16SD metanephroi showed signs of acute rejection as hypercellular glomeruli and mononuclear cell infiltration in the interstitium. The E16CsASD and E17CsASD metanephroi formed mature nephrons and collecting ducts with few lymphocytic infiltrates. After CsA was discontinued, the E16CsASD and E17CsASD metanephroi were rejected fully within 21 days. (2) 4 weeks after implantation, the E15SD metanephroi were enlarged, became vascularized, and developed mature tubules and glomeruli; however, they were rejected by 100 days after implantation. The E15 Lewis metanephroi were fully rejected within two weeks in the BN adult rats. With CsA administrated, the E15 Lewis metanephroi developed normal mature nephrons and collecting ducts within the adult BN rats. If CsA was discontinued, the E15CsABN metanephroi were rejected. (3) The E15CsASD metanephroi had significantly lower values of wet weight (P = 0.006) and higher values of creatinine clearances (P = 0.007) than the E15SD metanephros transplants, but were identical to those of the E16CsASD metanephroi (P = 0.948, P = 0.840). (4) The metanephroi did not grow or differentiate in the rats without host kidney resection. CONCLUSIONS: (1) Cyclosporin A may suppress graft rejection, thus normalizing the growth and function of fetal metanephroi in the omenta of host rats. (2) A variety of factors affect the growth and development of allografted metanephroi, whereas rejection remains the major one.

Specific COX-2 inhibitor NS398 induces apoptosis in human liver cancer cell line HepG2 through BCL-2.

AIM: To evaluate the effects of NS-398, a cyclooxygenase-2 (COX-2) inhibitor, on the proliferation and apoptosis of HepG2 cells. METHODS: The effects of NS-398 on the proliferation of HepG2 cells were evaluated by MTT. DNA fragmentation gel analysis was used to analyze the apoptotic cells. DNA ploidy and apoptotic cell percentage were calculated by flow cytometry. The expression of COX-2 and Bcl-2 mRNA was identified by competitive RT-PCR. Furthermore, expression level of Bcl-2 was detected using Western blot in HepG2 after treated with NS-398. RESULTS: NS-398 inhibited cell proliferation and induced apoptosis of HepG2 cells in a concentration-dependent manner. DNA ploidy analysis showed that S phase cells were significantly decreased with increase of NS-398 concentration. The quiescent G0/G1 phase was accumulated with decrease of Bcl-2 mRNA. Whereas NS-398 had no effect on the expression of COX-2 mRNA, and no correlations were found between COX-2 mRNA and HepG2 cell proliferation and apoptosis induced by NS-398 (r = 0.056 and r = 0.119, respectively). Bcl-2 protein level was inhibited after treated with NS-398. CONCLUSION: NS-398 significantly inhibits the proliferation and induces apoptosis of HepG2 cells. Mechanisms involved may be accumulation of quiescent G0/G1 phase and decrease of Bcl-2 expression.