Figure 3. TPPPS blocks the gp85 protein of ALV-J.

The gp85 protein of ALV-J was expressed in Pichia pastoris and identified through Western blot analysis. M, PageRuler pre-stained protein ladder; lane 1, the culture supernatant of negative P. pastoris transformant; lane 2, the purified recombinant gp85 protein (A). A blocking ELISA was established on the basis of the expressed gp85 and TPPPS (B). The chicken spleen cell membrane proteins were isolated and identified through SDS–PAGE. M, PageRuler pre-stained protein ladder; lane 1, the isolated membrane proteins; lane 2, the residual cytoplasm proteins; lane 3, the whole cell proteins (C). The wells coated with the membrane proteins were used as the control for gp85 (D). β-actin protein-coated wells served as the negative control (CN) in both ELISAs, and their OD₄₅₀ values were determined. The cut-off point was calculated by mean + 3SD. The P/N value was calculated by the following equation: P/N = Positive mean/Negative mean. All values shown are presented as the means ± SD of three independent experiments. The transverse line in the histogram represents the cut-off point. An asterisk indicates that the value of the corresponding group was significantly different from that of non-TPPPS-treated group (0 μg/ml; P < 0.05).