Preparation of nanoscale lipid microbubbles modified with hepatoma glypican 3 antibody and targeting study in vitro

Abstract:

Objectives：To develop a method for the preparation of hepatoma glypican 3（GPC3） antibody modified lipid microbubble and to evaluate its efficiency of targeting hepatoma cells in vitro. Methods：Lipid microbubbles were prepared using the mechanical oscil－lation method and the morphology and size of the microbubbles were determined using optical and electron microscopy. The biotin-a－vidin bridge was used to link the GPC3 antibody with the microbubbles and the efficiency of conjugation was determined using flow cytometry. Expressions of GPC3 in 3 kinds of common hepatoma cells were investigated using the immunocytochemical assay. GPC3 antibody modified microbubbles were targeted to hepatoma cells in vitro and the targeting efficiency was determined using confocal analysis. Results：Lipid microbubbles showed a round shape and were evenly distributed without significant aggregation. Diameter of the microbubbles was between 350 nm and 450 nm. 85.05% microbubbles were successfully conjugated with GPC3 antibodies. Fur－thermore，SMMC-7721，HepG2 and Huh7 cells showed positive GPC3 expressions and confocal analysis revealed that the microbub－bles could specifically bind to SMMC-7721 cells. Conclusions：Nanoscale lipid microbubbles conjugated with GPC3 antibody are successfully obtained via biotin-avidin bridging. GPC3 antibody modified microbubbles could selectively target hepatoma cells. Our study provides experimental support for the application of antibody modified nanoscale microbubbles in diagnosis and treatment.