[Association of receptor-mediated endocytosis and autophagy with apoptosis].

Objective: To evaluate the relationship between receptor-mediated endocytosis, autophagosome formation and apoptosis by observing the morphological changes of mouse peritoneal macrophages in the course of receptor-mediated endocytotic activities, autophagy and apoptosis.
Methods: Mouse peritoneal macrophages were incubated with horseradish peroxidase-labeled concanavalin A (ConA-HRP), and morphological examinations were performed at different time points after the incubation.
Results: After the incubation of the macrophages with ConA-HRP, ConA-HRP was observed to enter the vesicles by way of receptor-mediated endocytosis. Three kinds of endosomes were observed, namely vesicles, tubes and double-membrane sheets. The double-membrane sheets enveloped a portion of the cytoplasm and organelles, thus giving rise to vesicles, or the autophagosomes, which later fused with lysosome, followed by the apoptosis of the macrophages.
Conclusion: Receptor-mediated endocytosis of ConA-HRP is associated with autophagy and apoptosis.