FIG 7.

Detection of the ability of virion incorporation and proteolytic process of various mutant ALV-J strains. (a) Detection of virion incorporation through quantifying Env protein and p27 in the supernatants of wide-type, N17, N62, and N193 mutants. Env protein and β-actin in the cell lysates were regarded as references. Env protein and β-actin were detected by Western blot while p27 was detected by ELISA. (b) Supernatants of wide-type, N17, N62, and N193 mutants were harvested at 1 to 6 days postinfection and then tittered for TCID₅₀ using the Spearman-Kärber method. (c) Env protein processing was quantified by detecting gp37 in the cell lysates of wide-type, N17, N62, and N193 using JE9 and rabbit anti-gp37 antibodies.