Binding and Endocytosis of Bovine Hololactoferrin by the Parasite Entamoeba histolytica

Figure 7

E. histolytica trophozoites degrade B-holo-Lf by means of cysteine proteases. Amoebae (10⁶ cells) were maintained in BI-S-33 or low-iron medium for 4 h at 37°C. Next, the amoebae were harvested and washed and cells from the pellet were disrupted by freeze-thawing. Proteins from crude cell extract (CCE) and culture supernatant (SN) were separated by electrophoresis on a 10% SDS-PAGE copolymerized with 0.1% of B-holo-Lf. After that, the gels were incubated with a buffer (pH 5.0) and stained with Coomassie blue. CCEs of nonvirulent amoebae (NV) and virulent amoebae (V) were treated with the protease inhibitors indicated (lanes 9–18). Result is representative of three independent experiments.