OL-024 vfr: A novel locus affecting cysteine protease production in Streptococcus pyogenes
International Journal of Infectious Diseases
Aim: To investigate the effect of activation of canonical Wnt signaling pathway on the proliferation and differentiation of rat heaptic oval cells in vitro. Methods: WB-F344 cells were treated with recombinant wnt3a (20, 40, 80, 160, 200 ng/ml) in the serum-free medium for 24 hours. Cell proliferation was measured by Brdu incorporation analysis, un-treated WB-F344 cells were taken as control. After treatment with Wnt3a (160ng/ml) for 24 hours, the subcellular localization and protein expression
... protein expression of β-catenin in Wnt3a treated and untreated WB-F344 cells were examined by Immunofluorescence Staining and Western-blot analysis. CyclinD1 mRNA expression was determined by semi-quantitative RT-PCR; The mRNA levels of some phenotypic markers, including AFP, CK-19,ALB, and two hepatic nuclear factors, HNF-4, HNF-6 were determined by RT-PCR. CK-19 and AFP protein expression were examined by Western-blot analysis. Results: We found that Wnt3a promoted proliferation of WB-F344 cells. Stimulation of WB-F344 cells with recombinant Wnt3a resulted in the accumulation of the transcriptional activator β-catenin, together with its translocation into the nucleus, and the upregulation of typical Wnt target genes cyclin D1 After 3 days of Wnt3a treatment in the absence of any serum, these cells retained their bipotential to express several specific hepatocyte and cholangiocyte phenotypic markers, such as AFP, CK-19 following activation of canonical Wnt signaling pathway. Conclusion: The canonical Wnt signaling pathway promotes proliferation and self-renewal of rat hepatic oval cells.