Figure 6. Effects of transient treatment with rgcTGF-β1 for 24 h on cell viability and ALK5 expression in grass carp PBL and HKL.

In this study, treatment with 100 ng/ml of native or heat treated rgcTGF-β1 was carried out for 24 h and subsequently terminated by substitution of fresh medium without drug. After that, the cells were incubated for additional 24, 48 and 72 h. Time course effects of transient treatment with TGF-β1 for 24 h on cell viability of PBL and HKL were shown (A). Relative cell viability was expressed as the fold changes of the respective heat treated group at each time point. Data presented (mean±SEM, N = 4) are representative results of three individual experiments. In addition, the ALK5 mRNA (B) and protein (C–D) levels in PBL (left panels) or HKL (right panels) with additional 48 h incubation after TGF-β1 transient treatment were determined. Relative mRNA expression and protein levels of ALK5 were analyzed by using β-actin as an internal reference and expressed as the fold changes of the heat treated group. Data presented (mean±SEM, N = 4) are representative results from three individual experiments. Control, medium was replaced with fresh one after 24 h incubation; TGF-β1, TGF-β1 treatment for 24 h was terminated by fresh medium. The asterisk (*) denotes a significant difference at P<0.05.