Fig. 5.

Apo(a) expression inverts the effect of sortilin overexpression on apoB secretion. HepG2 cells stably expressing 17K-apo(a) (A) or wild-type HepG2 cells (B) were transiently transfected with an expression vector encoding sortilin or the corresponding empty vector (pcDNA). The cells were subjected to a pulse-chase protocol followed by immunoprecipitation of medium samples using an anti-apoB antibody. The growth medium was supplemented with oleic acid throughout the preincubation, pulse-labeling, and chase periods. Representative fluorographs and the results of densitometric analysis are shown; the latter are the means ± SEM of at least three independent experiments. Significance compared to pcDNA is indicated through asterisks, where ∗P<0.05 and ∗∗P<0.01. apo(a), apolipoprotein(a).